ngsw-worker.js

(function () {
'use strict';

/**
 * @license
 * Copyright Google Inc. All Rights Reserved.
 *
 * Use of this source code is governed by an MIT-style license that can be
 * found in the LICENSE file at https://angular.io/license
 */
/**
 * Adapts the service worker to its runtime environment.
 *
 * Mostly, this is used to mock out identifiers which are otherwise read
 * from the global scope.
 */
class Adapter {
    /**
     * Wrapper around the `Request` constructor.
     */
    newRequest(input, init) {
        return new Request(input, init);
    }
    /**
     * Wrapper around the `Response` constructor.
     */
    newResponse(body, init) { return new Response(body, init); }
    /**
     * Wrapper around the `Headers` constructor.
     */
    newHeaders(headers) { return new Headers(headers); }
    /**
     * Test if a given object is an instance of `Client`.
     */
    isClient(source) { return (source instanceof Client); }
    /**
     * Read the current UNIX time in milliseconds.
     */
    get time() { return Date.now(); }
    /**
     * Extract the pathname of a URL.
     */
    parseUrl(url, relativeTo) {
        const parsed = new URL(url, relativeTo);
        return { origin: parsed.origin, path: parsed.pathname };
    }
    /**
     * Wait for a given amount of time before completing a Promise.
     */
    timeout(ms) {
        return new Promise(resolve => { setTimeout(() => resolve(), ms); });
    }
}

/**
 * @license
 * Copyright Google Inc. All Rights Reserved.
 *
 * Use of this source code is governed by an MIT-style license that can be
 * found in the LICENSE file at https://angular.io/license
 */
/**
 * An error returned in rejected promises if the given key is not found in the table.
 */
class NotFound {
    constructor(table, key) {
        this.table = table;
        this.key = key;
    }
}

/**
 * @license
 * Copyright Google Inc. All Rights Reserved.
 *
 * Use of this source code is governed by an MIT-style license that can be
 * found in the LICENSE file at https://angular.io/license
 */
/**
 * An implementation of a `Database` that uses the `CacheStorage` API to serialize
 * state within mock `Response` objects.
 */
class CacheDatabase {
    constructor(scope, adapter) {
        this.scope = scope;
        this.adapter = adapter;
        this.tables = new Map();
    }
    'delete'(name) {
        if (this.tables.has(name)) {
            this.tables.delete(name);
        }
        return this.scope.caches.delete(`ngsw:db:${name}`);
    }
    list() {
        return this.scope.caches.keys().then(keys => keys.filter(key => key.startsWith('ngsw:db:')));
    }
    open(name) {
        if (!this.tables.has(name)) {
            const table = this.scope.caches.open(`ngsw:db:${name}`)
                .then(cache => new CacheTable(name, cache, this.adapter));
            this.tables.set(name, table);
        }
        return this.tables.get(name);
    }
}
/**
 * A `Table` backed by a `Cache`.
 */
class CacheTable {
    constructor(table, cache, adapter) {
        this.table = table;
        this.cache = cache;
        this.adapter = adapter;
    }
    request(key) { return this.adapter.newRequest('/' + key); }
    'delete'(key) { return this.cache.delete(this.request(key)); }
    keys() {
        return this.cache.keys().then(keys => keys.map(key => key.substr(1)));
    }
    read(key) {
        return this.cache.match(this.request(key)).then(res => {
            if (res === undefined) {
                return Promise.reject(new NotFound(this.table, key));
            }
            return res.json();
        });
    }
    write(key, value) {
        return this.cache.put(this.request(key), this.adapter.newResponse(JSON.stringify(value)));
    }
}

/**
 * @license
 * Copyright Google Inc. All Rights Reserved.
 *
 * Use of this source code is governed by an MIT-style license that can be
 * found in the LICENSE file at https://angular.io/license
 */
var UpdateCacheStatus;
(function (UpdateCacheStatus) {
    UpdateCacheStatus[UpdateCacheStatus["NOT_CACHED"] = 0] = "NOT_CACHED";
    UpdateCacheStatus[UpdateCacheStatus["CACHED_BUT_UNUSED"] = 1] = "CACHED_BUT_UNUSED";
    UpdateCacheStatus[UpdateCacheStatus["CACHED"] = 2] = "CACHED";
})(UpdateCacheStatus || (UpdateCacheStatus = {}));

/**
 * @license
 * Copyright Google Inc. All Rights Reserved.
 *
 * Use of this source code is governed by an MIT-style license that can be
 * found in the LICENSE file at https://angular.io/license
 */
/**
 * Compute the SHA1 of the given string
 *
 * see http://csrc.nist.gov/publications/fips/fips180-4/fips-180-4.pdf
 *
 * WARNING: this function has not been designed not tested with security in mind.
 *          DO NOT USE IT IN A SECURITY SENSITIVE CONTEXT.
 *
 * Borrowed from @angular/compiler/src/i18n/digest.ts
 */
function sha1(str) {
    const utf8 = str;
    const words32 = stringToWords32(utf8, Endian.Big);
    return _sha1(words32, utf8.length * 8);
}
function sha1Binary(buffer) {
    const words32 = arrayBufferToWords32(buffer, Endian.Big);
    return _sha1(words32, buffer.byteLength * 8);
}
function _sha1(words32, len) {
    const w = new Array(80);
    let [a, b, c, d, e] = [0x67452301, 0xefcdab89, 0x98badcfe, 0x10325476, 0xc3d2e1f0];
    words32[len >> 5] |= 0x80 << (24 - len % 32);
    words32[((len + 64 >> 9) << 4) + 15] = len;
    for (let i = 0; i < words32.length; i += 16) {
        const [h0, h1, h2, h3, h4] = [a, b, c, d, e];
        for (let j = 0; j < 80; j++) {
            if (j < 16) {
                w[j] = words32[i + j];
            }
            else {
                w[j] = rol32(w[j - 3] ^ w[j - 8] ^ w[j - 14] ^ w[j - 16], 1);
            }
            const [f, k] = fk(j, b, c, d);
            const temp = [rol32(a, 5), f, e, k, w[j]].reduce(add32);
            [e, d, c, b, a] = [d, c, rol32(b, 30), a, temp];
        }
        [a, b, c, d, e] = [add32(a, h0), add32(b, h1), add32(c, h2), add32(d, h3), add32(e, h4)];
    }
    return byteStringToHexString(words32ToByteString([a, b, c, d, e]));
}
function add32(a, b) {
    return add32to64(a, b)[1];
}
function add32to64(a, b) {
    const low = (a & 0xffff) + (b & 0xffff);
    const high = (a >>> 16) + (b >>> 16) + (low >>> 16);
    return [high >>> 16, (high << 16) | (low & 0xffff)];
}
// Rotate a 32b number left `count` position
function rol32(a, count) {
    return (a << count) | (a >>> (32 - count));
}
var Endian;
(function (Endian) {
    Endian[Endian["Little"] = 0] = "Little";
    Endian[Endian["Big"] = 1] = "Big";
})(Endian || (Endian = {}));
function fk(index, b, c, d) {
    if (index < 20) {
        return [(b & c) | (~b & d), 0x5a827999];
    }
    if (index < 40) {
        return [b ^ c ^ d, 0x6ed9eba1];
    }
    if (index < 60) {
        return [(b & c) | (b & d) | (c & d), 0x8f1bbcdc];
    }
    return [b ^ c ^ d, 0xca62c1d6];
}
function stringToWords32(str, endian) {
    const words32 = Array((str.length + 3) >>> 2);
    for (let i = 0; i < words32.length; i++) {
        words32[i] = wordAt(str, i * 4, endian);
    }
    return words32;
}
function arrayBufferToWords32(buffer, endian) {
    const words32 = Array((buffer.byteLength + 3) >>> 2);
    const view = new Uint8Array(buffer);
    for (let i = 0; i < words32.length; i++) {
        words32[i] = wordAt(view, i * 4, endian);
    }
    return words32;
}
function byteAt(str, index) {
    if (typeof str === 'string') {
        return index >= str.length ? 0 : str.charCodeAt(index) & 0xff;
    }
    else {
        return index >= str.byteLength ? 0 : str[index] & 0xff;
    }
}
function wordAt(str, index, endian) {
    let word = 0;
    if (endian === Endian.Big) {
        for (let i = 0; i < 4; i++) {
            word += byteAt(str, index + i) << (24 - 8 * i);
        }
    }
    else {
        for (let i = 0; i < 4; i++) {
            word += byteAt(str, index + i) << 8 * i;
        }
    }
    return word;
}
function words32ToByteString(words32) {
    return words32.reduce((str, word) => str + word32ToByteString(word), '');
}
function word32ToByteString(word) {
    let str = '';
    for (let i = 0; i < 4; i++) {
        str += String.fromCharCode((word >>> 8 * (3 - i)) & 0xff);
    }
    return str;
}
function byteStringToHexString(str) {
    let hex = '';
    for (let i = 0; i < str.length; i++) {
        const b = byteAt(str, i);
        hex += (b >>> 4).toString(16) + (b & 0x0f).toString(16);
    }
    return hex.toLowerCase();
}
// x and y decimal, lowest significant digit first
function addBigInt(x, y) {
    let sum = '';
    const len = Math.max(x.length, y.length);
    for (let i = 0, carry = 0; i < len || carry; i++) {
        const tmpSum = carry + +(x[i] || 0) + +(y[i] || 0);
        if (tmpSum >= 10) {
            carry = 1;
            sum += tmpSum - 10;
        }
        else {
            carry = 0;
            sum += tmpSum;
        }
    }
    return sum;
}
function numberTimesBigInt(num, b) {
    let product = '';
    let bToThePower = b;
    for (; num !== 0; num = num >>> 1) {
        if (num & 1)
            product = addBigInt(product, bToThePower);
        bToThePower = addBigInt(bToThePower, bToThePower);
    }
    return product;
}

/**
 * @license
 * Copyright Google Inc. All Rights Reserved.
 *
 * Use of this source code is governed by an MIT-style license that can be
 * found in the LICENSE file at https://angular.io/license
 */
/**
 * A group of assets that are cached in a `Cache` and managed by a given policy.
 *
 * Concrete classes derive from this base and specify the exact caching policy.
 */
class AssetGroup {
    constructor(scope, adapter, idle, config, hashes, db, prefix) {
        this.scope = scope;
        this.adapter = adapter;
        this.idle = idle;
        this.config = config;
        this.hashes = hashes;
        this.db = db;
        this.prefix = prefix;
        /**
         * A deduplication cache, to make sure the SW never makes two network requests
         * for the same resource at once. Managed by `fetchAndCacheOnce`.
         */
        this.inFlightRequests = new Map();
        /**
         * Regular expression patterns.
         */
        this.patterns = [];
        this.name = config.name;
        // Patterns in the config are regular expressions disguised as strings. Breathe life into them.
        this.patterns = this.config.patterns.map(pattern => new RegExp(pattern));
        // This is the primary cache, which holds all of the cached requests for this group. If a
        // resource
        // isn't in this cache, it hasn't been fetched yet.
        this.cache = this.scope.caches.open(`${this.prefix}:${this.config.name}:cache`);
        // This is the metadata table, which holds specific information for each cached URL, such as
        // the timestamp of when it was added to the cache.
        this.metadata = this.db.open(`${this.prefix}:${this.config.name}:meta`);
        // Determine the origin from the registration scope. This is used to differentiate between
        // relative and absolute URLs.
        this.origin =
            this.adapter.parseUrl(this.scope.registration.scope, this.scope.registration.scope).origin;
    }
    async cacheStatus(url) {
        const cache = await this.cache;
        const meta = await this.metadata;
        const res = await cache.match(this.adapter.newRequest(url));
        if (res === undefined) {
            return UpdateCacheStatus.NOT_CACHED;
        }
        try {
            const data = await meta.read(url);
            if (!data.used) {
                return UpdateCacheStatus.CACHED_BUT_UNUSED;
            }
        }
        catch (_) {
            // Error on the side of safety and assume cached.
        }
        return UpdateCacheStatus.CACHED;
    }
    /**
     * Clean up all the cached data for this group.
     */
    async cleanup() {
        await this.scope.caches.delete(`${this.prefix}:${this.config.name}:cache`);
        await this.db.delete(`${this.prefix}:${this.config.name}:meta`);
    }
    /**
     * Process a request for a given resource and return it, or return null if it's not available.
     */
    async handleFetch(req, ctx) {
        const url = this.getConfigUrl(req.url);
        // Either the request matches one of the known resource URLs, one of the patterns for
        // dynamically matched URLs, or neither. Determine which is the case for this request in
        // order to decide how to handle it.
        if (this.config.urls.indexOf(url) !== -1 || this.patterns.some(pattern => pattern.test(url))) {
            // This URL matches a known resource. Either it's been cached already or it's missing, in
            // which case it needs to be loaded from the network.
            // Open the cache to check whether this resource is present.
            const cache = await this.cache;
            // Look for a cached response. If one exists, it can be used to resolve the fetch
            // operation.
            const cachedResponse = await cache.match(req);
            if (cachedResponse !== undefined) {
                // A response has already been cached (which presumably matches the hash for this
                // resource). Check whether it's safe to serve this resource from cache.
                if (this.hashes.has(url)) {
                    // This resource has a hash, and thus is versioned by the manifest. It's safe to return
                    // the response.
                    return cachedResponse;
                }
                else {
                    // This resource has no hash, and yet exists in the cache. Check how old this request is
                    // to make sure it's still usable.
                    if (await this.needToRevalidate(req, cachedResponse)) {
                        this.idle.schedule(`revalidate(${this.prefix}, ${this.config.name}): ${req.url}`, async () => { await this.fetchAndCacheOnce(req); });
                    }
                    // In either case (revalidation or not), the cached response must be good.
                    return cachedResponse;
                }
            }
            // No already-cached response exists, so attempt a fetch/cache operation. The original request
            // may specify things like credential inclusion, but for assets these are not honored in order
            // to avoid issues with opaque responses. The SW requests the data itself.
            const res = await this.fetchAndCacheOnce(this.adapter.newRequest(req.url));
            // If this is successful, the response needs to be cloned as it might be used to respond to
            // multiple fetch operations at the same time.
            return res.clone();
        }
        else {
            return null;
        }
    }
    getConfigUrl(url) {
        // If the URL is relative to the SW's own origin, then only consider the path relative to
        // the domain root. Determine this by checking the URL's origin against the SW's.
        const parsed = this.adapter.parseUrl(url, this.scope.registration.scope);
        if (parsed.origin === this.origin) {
            // The URL is relative to the SW's origin domain.
            return parsed.path;
        }
        else {
            return url;
        }
    }
    /**
     * Some resources are cached without a hash, meaning that their expiration is controlled
     * by HTTP caching headers. Check whether the given request/response pair is still valid
     * per the caching headers.
     */
    async needToRevalidate(req, res) {
        // Three different strategies apply here:
        // 1) The request has a Cache-Control header, and thus expiration needs to be based on its age.
        // 2) The request has an Expires header, and expiration is based on the current timestamp.
        // 3) The request has no applicable caching headers, and must be revalidated.
        if (res.headers.has('Cache-Control')) {
            // Figure out if there is a max-age directive in the Cache-Control header.
            const cacheControl = res.headers.get('Cache-Control');
            const cacheDirectives = cacheControl
                .split(',')
                .map(v => v.trim())
                .map(v => v.split('='));
            // Lowercase all the directive names.
            cacheDirectives.forEach(v => v[0] = v[0].toLowerCase());
            // Find the max-age directive, if one exists.
            const cacheAge = cacheDirectives.filter(v => v[0] === 'max-age').map(v => v[1])[0];
            if (cacheAge.length === 0) {
                // No usable TTL defined. Must assume that the response is stale.
                return true;
            }
            try {
                const maxAge = 1000 * parseInt(cacheAge);
                // Determine the origin time of this request. If the SW has metadata on the request (which
                // it
                // should), it will have the time the request was added to the cache. If it doesn't for some
                // reason, the request may have a Date header which will serve the same purpose.
                let ts;
                try {
                    // Check the metadata table. If a timestamp is there, use it.
                    const metaTable = await this.metadata;
                    ts = (await metaTable.read(req.url)).ts;
                }
                catch (e) {
                    // Otherwise, look for a Date header.
                    const date = res.headers.get('Date');
                    if (date === null) {
                        // Unable to determine when this response was created. Assume that it's stale, and
                        // revalidate it.
                        return true;
                    }
                    ts = Date.parse(date);
                }
                const age = this.adapter.time - ts;
                return age < 0 || age > maxAge;
            }
            catch (e) {
                // Assume stale.
                return true;
            }
        }
        else if (res.headers.has('Expires')) {
            // Determine if the expiration time has passed.
            const expiresStr = res.headers.get('Expires');
            try {
                // The request needs to be revalidated if the current time is later than the expiration
                // time, if it parses correctly.
                return this.adapter.time > Date.parse(expiresStr);
            }
            catch (e) {
                // The expiration date failed to parse, so revalidate as a precaution.
                return true;
            }
        }
        else {
            // No way to evaluate staleness, so assume the response is already stale.
            return true;
        }
    }
    /**
     * Fetch the complete state of a cached resource, or return null if it's not found.
     */
    async fetchFromCacheOnly(url) {
        const cache = await this.cache;
        const metaTable = await this.metadata;
        // Lookup the response in the cache.
        const response = await cache.match(this.adapter.newRequest(url));
        if (response === undefined) {
            // It's not found, return null.
            return null;
        }
        // Next, lookup the cached metadata.
        let metadata = undefined;
        try {
            metadata = await metaTable.read(url);
        }
        catch (e) {
            // Do nothing, not found. This shouldn't happen, but it can be handled.
        }
        // Return both the response and any available metadata.
        return { response, metadata };
    }
    /**
     * Lookup all resources currently stored in the cache which have no associated hash.
     */
    async unhashedResources() {
        const cache = await this.cache;
        // Start with the set of all cached URLs.
        return (await cache.keys())
            .filter(url => !this.hashes.has(url));
    }
    /**
     * Fetch the given resource from the network, and cache it if able.
     */
    async fetchAndCacheOnce(req, used = true) {
        // The `inFlightRequests` map holds information about which caching operations are currently
        // underway for known resources. If this request appears there, another "thread" is already
        // in the process of caching it, and this work should not be duplicated.
        if (this.inFlightRequests.has(req.url)) {
            // There is a caching operation already in progress for this request. Wait for it to
            // complete, and hopefully it will have yielded a useful response.
            return this.inFlightRequests.get(req.url);
        }
        // No other caching operation is being attempted for this resource, so it will be owned here.
        // Go to the network and get the correct version.
        const fetchOp = this.fetchFromNetwork(req);
        // Save this operation in `inFlightRequests` so any other "thread" attempting to cache it
        // will block on this chain instead of duplicating effort.
        this.inFlightRequests.set(req.url, fetchOp);
        // Make sure this attempt is cleaned up properly on failure.
        try {
            // Wait for a response. If this fails, the request will remain in `inFlightRequests`
            // indefinitely.
            const res = await fetchOp;
            // It's very important that only successful responses are cached. Unsuccessful responses
            // should never be cached as this can completely break applications.
            if (!res.ok) {
                throw new Error(`Response not Ok (fetchAndCacheOnce): request for ${req.url} returned response ${res.status} ${res.statusText}`);
            }
            // This response is safe to cache (as long as it's cloned). Wait until the cache operation
            // is complete.
            const cache = await this.scope.caches.open(`${this.prefix}:${this.config.name}:cache`);
            await cache.put(req, res.clone());
            // If the request is not hashed, update its metadata, especially the timestamp. This is needed
            // for future determination of whether this cached response is stale or not.
            if (!this.hashes.has(req.url)) {
                // Metadata is tracked for requests that are unhashed.
                const meta = { ts: this.adapter.time, used };
                const metaTable = await this.metadata;
                await metaTable.write(req.url, meta);
            }
            return res;
        }
        finally {
            // Finally, it can be removed from `inFlightRequests`. This might result in a double-remove
            // if some other  chain was already making this request too, but that won't hurt anything.
            this.inFlightRequests.delete(req.url);
        }
    }
    async fetchFromNetwork(req, redirectLimit = 3) {
        // Make a cache-busted request for the resource.
        const res = await this.cacheBustedFetchFromNetwork(req);
        // Check for redirected responses, and follow the redirects.
        if (res['redirected'] && !!res.url) {
            // If the redirect limit is exhausted, fail with an error.
            if (redirectLimit === 0) {
                throw new Error(`Response hit redirect limit (fetchFromNetwork): request redirected too many times, next is ${res.url}`);
            }
            // Unwrap the redirect directly.
            return this.fetchFromNetwork(this.adapter.newRequest(res.url), redirectLimit - 1);
        }
        return res;
    }
    /**
     * Load a particular asset from the network, accounting for hash validation.
     */
    async cacheBustedFetchFromNetwork(req) {
        const url = this.getConfigUrl(req.url);
        // If a hash is available for this resource, then compare the fetched version with the
        // canonical hash. Otherwise, the network version will have to be trusted.
        if (this.hashes.has(url)) {
            // It turns out this resource does have a hash. Look it up. Unless the fetched version
            // matches this hash, it's invalid and the whole manifest may need to be thrown out.
            const canonicalHash = this.hashes.get(url);
            // Ideally, the resource would be requested with cache-busting to guarantee the SW gets
            // the freshest version. However, doing this would eliminate any chance of the response
            // being in the HTTP cache. Given that the browser has recently actively loaded the page,
            // it's likely that many of the responses the SW needs to cache are in the HTTP cache and
            // are fresh enough to use. In the future, this could be done by setting cacheMode to
            // *only* check the browser cache for a cached version of the resource, when cacheMode is
            // fully supported. For now, the resource is fetched directly, without cache-busting, and
            // if the hash test fails a cache-busted request is tried before concluding that the
            // resource isn't correct. This gives the benefit of acceleration via the HTTP cache
            // without the risk of stale data, at the expense of a duplicate request in the event of
            // a stale response.
            // Fetch the resource from the network (possibly hitting the HTTP cache).
            const networkResult = await this.safeFetch(req);
            // Decide whether a cache-busted request is necessary. It might be for two independent
            // reasons: either the non-cache-busted request failed (hopefully transiently) or if the
            // hash of the content retrieved does not match the canonical hash from the manifest. It's
            // only valid to access the content of the first response if the request was successful.
            let makeCacheBustedRequest = networkResult.ok;
            if (makeCacheBustedRequest) {
                // The request was successful. A cache-busted request is only necessary if the hashes
                // don't match. Compare them, making sure to clone the response so it can be used later
                // if it proves to be valid.
                const fetchedHash = sha1Binary(await networkResult.clone().arrayBuffer());
                makeCacheBustedRequest = (fetchedHash !== canonicalHash);
            }
            // Make a cache busted request to the network, if necessary.
            if (makeCacheBustedRequest) {
                // Hash failure, the version that was retrieved under the default URL did not have the
                // hash expected. This could be because the HTTP cache got in the way and returned stale
                // data, or because the version on the server really doesn't match. A cache-busting
                // request will differentiate these two situations.
                // TODO: handle case where the URL has parameters already (unlikely for assets).
                const cacheBustReq = this.adapter.newRequest(this.cacheBust(req.url));
                const cacheBustedResult = await this.safeFetch(cacheBustReq);
                // If the response was unsuccessful, there's nothing more that can be done.
                if (!cacheBustedResult.ok) {
                    throw new Error(`Response not Ok (cacheBustedFetchFromNetwork): cache busted request for ${req.url} returned response ${cacheBustedResult.status} ${cacheBustedResult.statusText}`);
                }
                // Hash the contents.
                const cacheBustedHash = sha1Binary(await cacheBustedResult.clone().arrayBuffer());
                // If the cache-busted version doesn't match, then the manifest is not an accurate
                // representation of the server's current set of files, and the SW should give up.
                if (canonicalHash !== cacheBustedHash) {
                    throw new Error(`Hash mismatch (cacheBustedFetchFromNetwork): ${req.url}: expected ${canonicalHash}, got ${cacheBustedHash} (after cache busting)`);
                }
                // If it does match, then use the cache-busted result.
                return cacheBustedResult;
            }
            // Excellent, the version from the network matched on the first try, with no need for
            // cache-busting. Use it.
            return networkResult;
        }
        else {
            // This URL doesn't exist in our hash database, so it must be requested directly.
            return this.safeFetch(req);
        }
    }
    /**
     * Possibly update a resource, if it's expired and needs to be updated. A no-op otherwise.
     */
    async maybeUpdate(updateFrom, req, cache) {
        const url = this.getConfigUrl(req.url);
        const meta = await this.metadata;
        // Check if this resource is hashed and already exists in the cache of a prior version.
        if (this.hashes.has(url)) {
            const hash = this.hashes.get(url);
            // Check the caches of prior versions, using the hash to ensure the correct version of
            // the resource is loaded.
            const res = await updateFrom.lookupResourceWithHash(url, hash);
            // If a previously cached version was available, copy it over to this cache.
            if (res !== null) {
                // Copy to this cache.
                await cache.put(req, res);
                await meta.write(req.url, { ts: this.adapter.time, used: false });
                // No need to do anything further with this resource, it's now cached properly.
                return true;
            }
        }
        // No up-to-date version of this resource could be found.
        return false;
    }
    /**
     * Construct a cache-busting URL for a given URL.
     */
    cacheBust(url) {
        return url + (url.indexOf('?') === -1 ? '?' : '&') + 'ngsw-cache-bust=' + Math.random();
    }
    async safeFetch(req) {
        try {
            return await this.scope.fetch(req);
        }
        catch (err) {
            return this.adapter.newResponse('', {
                status: 504,
                statusText: 'Gateway Timeout',
            });
        }
    }
}
/**
 * An `AssetGroup` that prefetches all of its resources during initialization.
 */
class PrefetchAssetGroup extends AssetGroup {
    async initializeFully(updateFrom) {
        // Open the cache which actually holds requests.
        const cache = await this.cache;
        // Cache all known resources serially. As this reduce proceeds, each Promise waits
        // on the last before starting the fetch/cache operation for the next request. Any
        // errors cause fall-through to the final Promise which rejects.
        await this.config.urls.reduce(async (previous, url) => {
            // Wait on all previous operations to complete.
            await previous;
            // Construct the Request for this url.
            const req = this.adapter.newRequest(url);
            // First, check the cache to see if there is already a copy of this resource.
            const alreadyCached = (await cache.match(req)) !== undefined;
            // If the resource is in the cache already, it can be skipped.
            if (alreadyCached) {
                return;
            }
            // If an update source is available.
            if (updateFrom !== undefined && await this.maybeUpdate(updateFrom, req, cache)) {
                return;
            }
            // Otherwise, go to the network and hopefully cache the response (if successful).
            await this.fetchAndCacheOnce(req, false);
        }, Promise.resolve());
        // Handle updating of unknown (unhashed) resources. This is only possible if there's
        // a source to update from.
        if (updateFrom !== undefined) {
            const metaTable = await this.metadata;
            // Select all of the previously cached resources. These are cached unhashed resources
            // from previous versions of the app, in any asset group.
            await (await updateFrom.previouslyCachedResources())
                .filter(url => this.config.urls.some(cacheUrl => cacheUrl === url) ||
                this.patterns.some(pattern => pattern.test(url)))
                .reduce(async (previous, url) => {
                await previous;
                const req = this.adapter.newRequest(url);
                // It's possible that the resource in question is already cached. If so,
                // continue to the next one.
                const alreadyCached = (await cache.match(req) !== undefined);
                if (alreadyCached) {
                    return;
                }
                // Get the most recent old version of the resource.
                const res = await updateFrom.lookupResourceWithoutHash(url);
                if (res === null || res.metadata === undefined) {
                    // Unexpected, but not harmful.
                    return;
                }
                // Write it into the cache. It may already be expired, but it can still serve
                // traffic until it's updated (stale-while-revalidate approach).
                await cache.put(req, res.response);
                await metaTable.write(url, Object.assign({}, res.metadata, { used: false }));
            }, Promise.resolve());
        }
    }
}
class LazyAssetGroup extends AssetGroup {
    async initializeFully(updateFrom) {
        // No action necessary if no update source is available - resources managed in this group
        // are all lazily loaded, so there's nothing to initialize.
        if (updateFrom === undefined) {
            return;
        }
        // Open the cache which actually holds requests.
        const cache = await this.cache;
        // Loop through the listed resources, caching any which are available.
        await this.config.urls.reduce(async (previous, url) => {
            // Wait on all previous operations to complete.
            await previous;
            // Construct the Request for this url.
            const req = this.adapter.newRequest(url);
            // First, check the cache to see if there is already a copy of this resource.
            const alreadyCached = (await cache.match(req)) !== undefined;
            // If the resource is in the cache already, it can be skipped.
            if (alreadyCached) {
                return;
            }
            const updated = await this.maybeUpdate(updateFrom, req, cache);
            if (this.config.updateMode === 'prefetch' && !updated) {
                // If the resource was not updated, either it was not cached before or
                // the previously cached version didn't match the updated hash. In that
                // case, prefetch update mode dictates that the resource will be updated,
                // except if it was not previously utilized. Check the status of the
                // cached resource to see.
                const cacheStatus = await updateFrom.recentCacheStatus(url);
                // If the resource is not cached, or was cached but unused, then it will be
                // loaded lazily.
                if (cacheStatus !== UpdateCacheStatus.CACHED) {
                    return;
                }
                // Update from the network.
                await this.fetchAndCacheOnce(req, false);
            }
        }, Promise.resolve());
    }
}

/**
 * @license
 * Copyright Google Inc. All Rights Reserved.
 *
 * Use of this source code is governed by an MIT-style license that can be
 * found in the LICENSE file at https://angular.io/license
 */
/**
 * Manages an instance of `LruState` and moves URLs to the head of the
 * chain when requested.
 */
class LruList {
    constructor(state) {
        if (state === undefined) {
            state = {
                head: null,
                tail: null,
                map: {},
                count: 0,
            };
        }
        this.state = state;
    }
    /**
     * The current count of URLs in the list.
     */
    get size() { return this.state.count; }
    /**
     * Remove the tail.
     */
    pop() {
        // If there is no tail, return null.
        if (this.state.tail === null) {
            return null;
        }
        const url = this.state.tail;
        // Special case if this is the last node.
        if (this.state.head === this.state.tail) {
            // When removing the last node, both head and tail pointers become null.
            this.state.head = null;
            this.state.tail = null;
        }
        else {
            // Normal node removal. All that needs to be done is to clear the next pointer
            // of the previous node and make it the new tail.
            const block = this.state.map[url];
            const previous = this.state.map[block.previous];
            this.state.tail = previous.url;
            previous.next = block.next;
        }
        // In any case, this URL is no longer tracked, so remove it from the count and the
        // map of tracked URLs.
        delete this.state.map[url];
        this.state.count--;
        // This URL has been successfully evicted.
        return url;
    }
    remove(url) {
        const node = this.state.map[url];
        if (node === undefined) {
            return false;
        }
        // Special case if removing the current head.
        if (this.state.head === url) {
            // The node is the current head. Special case the removal.
            if (node.next === null) {
                // This is the only node. Reset the cache to be empty.
                this.state.head = null;
                this.state.tail = null;
                this.state.map = {};
                this.state.count = 0;
                return true;
            }
            // There is at least one other node. Make the next node the new head.
            const next = this.state.map[node.next];
            next.previous = null;
            this.state.head = next.url;
            this.state.count--;
            return true;
        }
        // The node is not the head, so it has a previous. It may or may not be the tail.
        // If it is not, then it has a next. First, grab the previous node.
        const previous = this.state.map[node.previous];
        // Fix the forward pointer to skip over node and go directly to node.next.
        previous.next = node.next;
        // node.next may or may not be set. If it is, fix the back pointer to skip over node.
        // If it's not set, then this node happened to be the tail, and the tail needs to be
        // updated to point to the previous node (removing the tail).
        if (node.next !== null) {
            // There is a next node, fix its back pointer to skip this node.
            this.state.map[node.next].previous = node.previous;
        }
        else {
            // There is no next node - the accessed node must be the tail. Move the tail pointer.
            this.state.tail = node.previous;
        }
        // Count the removal.
        this.state.count--;
        return true;
    }
    accessed(url) {
        // When a URL is accessed, its node needs to be moved to the head of the chain.
        // This is accomplished in two steps:
        //
        // 1) remove the node from its position within the chain.
        // 2) insert the node as the new head.
        //
        // Sometimes, a URL is accessed which has not been seen before. In this case, step 1 can
        // be skipped completely (which will grow the chain by one). Of course, if the node is
        // already the head, this whole operation can be skipped.
        if (this.state.head === url) {
            // The URL is already in the head position, accessing it is a no-op.
            return;
        }
        // Look up the node in the map, and construct a new entry if it's
        const node = this.state.map[url] || { url, next: null, previous: null };
        // Step 1: remove the node from its position within the chain, if it is in the chain.
        if (this.state.map[url] !== undefined) {
            this.remove(url);
        }
        // Step 2: insert the node at the head of the chain.
        // First, check if there's an existing head node. If there is, it has previous: null.
        // Its previous pointer should be set to the node we're inserting.
        if (this.state.head !== null) {
            this.state.map[this.state.head].previous = url;
        }
        // The next pointer of the node being inserted gets set to the old head, before the head
        // pointer is updated to this node.
        node.next = this.state.head;
        // The new head is the new node.
        this.state.head = url;
        // If there is no tail, then this is the first node, and is both the head and the tail.
        if (this.state.tail === null) {
            this.state.tail = url;
        }
        // Set the node in the map of nodes (if the URL has been seen before, this is a no-op)
        // and count the insertion.
        this.state.map[url] = node;
        this.state.count++;
    }
}
/**
 * A group of cached resources determined by a set of URL patterns which follow a LRU policy
 * for caching.
 */
class DataGroup {
    constructor(scope, adapter, config, db, prefix) {
        this.scope = scope;
        this.adapter = adapter;
        this.config = config;
        this.db = db;
        this.prefix = prefix;
        /**
         * Tracks the LRU state of resources in this cache.
         */
        this._lru = null;
        this.patterns = this.config.patterns.map(pattern => new RegExp(pattern));
        this.cache = this.scope.caches.open(`${this.prefix}:dynamic:${this.config.name}:cache`);
        this.lruTable = this.db.open(`${this.prefix}:dynamic:${this.config.name}:lru`);
        this.ageTable = this.db.open(`${this.prefix}:dynamic:${this.config.name}:age`);
    }
    /**
     * Lazily initialize/load the LRU chain.
     */
    async lru() {
        if (this._lru === null) {
            const table = await this.lruTable;
            try {
                this._lru = new LruList(await table.read('lru'));
            }
            catch (e) {
                this._lru = new LruList();
            }
        }
        return this._lru;
    }
    /**
     * Sync the LRU chain to non-volatile storage.
     */
    async syncLru() {
        if (this._lru === null) {
            return;
        }
        const table = await this.lruTable;
        return table.write('lru', this._lru.state);
    }
    /**
     * Process a fetch event and return a `Response` if the resource is covered by this group,
     * or `null` otherwise.
     */
    async handleFetch(req, ctx) {
        // Do nothing
        if (!this.patterns.some(pattern => pattern.test(req.url))) {
            return null;
        }
        // Lazily initialize the LRU cache.
        const lru = await this.lru();
        // The URL matches this cache. First, check whether this is a mutating request or not.
        switch (req.method) {
            case 'OPTIONS':
                // Don't try to cache this - it's non-mutating, but is part of a mutating request.
                // Most likely SWs don't even see this, but this guard is here just in case.
                return null;
            case 'GET':
            case 'HEAD':
                // Handle the request with whatever strategy was selected.
                switch (this.config.strategy) {
                    case 'freshness':
                        return this.handleFetchWithFreshness(req, ctx, lru);
                    case 'performance':
                        return this.handleFetchWithPerformance(req, ctx, lru);
                    default:
                        throw new Error(`Unknown strategy: ${this.config.strategy}`);
                }
            default:
                // This was a mutating request. Assume the cache for this URL is no longer valid.
                const wasCached = lru.remove(req.url);
                // If there was a cached entry, remove it.
                if (wasCached) {
                    await this.clearCacheForUrl(req.url);
                }
                // Sync the LRU chain to non-volatile storage.
                await this.syncLru();
                // Finally, fall back on the network.
                return this.safeFetch(req);
        }
    }
    async handleFetchWithPerformance(req, ctx, lru) {
        let res = null;
        // Check the cache first. If the resource exists there (and is not expired), the cached
        // version can be used.
        const fromCache = await this.loadFromCache(req, lru);
        if (fromCache !== null) {
            res = fromCache.res;
            // Check the age of the resource.
            if (this.config.refreshAheadMs !== undefined && fromCache.age >= this.config.refreshAheadMs) {
                ctx.waitUntil(this.safeCacheResponse(req, this.safeFetch(req)));
            }
        }
        if (res !== null) {
            return res;
        }
        // No match from the cache. Go to the network. Note that this is not an 'await'
        // call, networkFetch is the actual Promise. This is due to timeout handling.
        const [timeoutFetch, networkFetch] = this.networkFetchWithTimeout(req);
        res = await timeoutFetch;
        // Since fetch() will always return a response, undefined indicates a timeout.
        if (res === undefined) {
            // The request timed out. Return a Gateway Timeout error.
            res = this.adapter.newResponse(null, { status: 504, statusText: 'Gateway Timeout' });
            // Cache the network response eventually.
            ctx.waitUntil(this.safeCacheResponse(req, networkFetch));
        }
        // The request completed in time, so cache it inline with the response flow.
        await this.cacheResponse(req, res, lru);
        return res;
    }
    async handleFetchWithFreshness(req, ctx, lru) {
        // Start with a network fetch.
        const [timeoutFetch, networkFetch] = this.networkFetchWithTimeout(req);
        let res;
        // If that fetch errors, treat it as a timed out request.
        try {
            res = await timeoutFetch;
        }
        catch (e) {
            res = undefined;
        }
        // If the network fetch times out or errors, fall back on the cache.
        if (res === undefined) {
            ctx.waitUntil(this.safeCacheResponse(req, networkFetch));
            // Ignore the age, the network response will be cached anyway due to the
            // behavior of freshness.
            const fromCache = await this.loadFromCache(req, lru);
            res = (fromCache !== null) ? fromCache.res : null;
        }
        else {
            await this.cacheResponse(req, res, lru, true);
        }
        // Either the network fetch didn't time out, or the cache yielded a usable response.
        // In either case, use it.
        if (res !== null) {
            return res;
        }
        // No response in the cache. No choice but to fall back on the full network fetch.
        res = await networkFetch;
        await this.cacheResponse(req, res, lru, true);
        return res;
    }
    networkFetchWithTimeout(req) {
        // If there is a timeout configured, race a timeout Promise with the network fetch.
        // Otherwise, just fetch from the network directly.
        if (this.config.timeoutMs !== undefined) {
            const networkFetch = this.scope.fetch(req);
            const safeNetworkFetch = (async () => {
                try {
                    return await networkFetch;
                }
                catch (err) {
                    return this.adapter.newResponse(null, {
                        status: 504,
                        statusText: 'Gateway Timeout',
                    });
                }
            })();
            const networkFetchUndefinedError = (async () => {
                try {
                    return await networkFetch;
                }
                catch (err) {
                    return undefined;
                }
            })();
            // Construct a Promise<undefined> for the timeout.
            const timeout = this.adapter.timeout(this.config.timeoutMs);
            // Race that with the network fetch. This will either be a Response, or `undefined`
            // in the event that the request errored or timed out.
            return [Promise.race([networkFetchUndefinedError, timeout]), safeNetworkFetch];
        }
        else {
            const networkFetch = this.safeFetch(req);
            // Do a plain fetch.
            return [networkFetch, networkFetch];
        }
    }
    async safeCacheResponse(req, res) {
        try {
            await this.cacheResponse(req, await res, await this.lru());
        }
        catch (e) {
            // TODO: handle this error somehow?
        }
    }
    async loadFromCache(req, lru) {
        // Look for a response in the cache. If one exists, return it.
        const cache = await this.cache;
        let res = await cache.match(req);
        if (res !== undefined) {
            // A response was found in the cache, but its age is not yet known. Look it up.
            try {
                const ageTable = await this.ageTable;
                const age = this.adapter.time - (await ageTable.read(req.url)).age;
                // If the response is young enough, use it.
                if (age <= this.config.maxAge) {
                    // Successful match from the cache. Use the response, after marking it as having
                    // been accessed.
                    lru.accessed(req.url);
                    return { res, age };
                }
                // Otherwise, or if there was an error, assume the response is expired, and evict it.
            }
            catch (e) {
                // Some error getting the age for the response. Assume it's expired.
            }
            lru.remove(req.url);
            await this.clearCacheForUrl(req.url);
            // TODO: avoid duplicate in event of network timeout, maybe.
            await this.syncLru();
        }
        return null;
    }
    /**
     * Operation for caching the response from the server. This has to happen all
     * at once, so that the cache and LRU tracking remain in sync. If the network request
     * completes before the timeout, this logic will be run inline with the response flow.
     * If the request times out on the server, an error will be returned but the real network
     * request will still be running in the background, to be cached when it completes.
     */
    async cacheResponse(req, res, lru, okToCacheOpaque = false) {
        // Only cache successful responses.
        if (!res.ok || (okToCacheOpaque && res.type === 'opaque')) {
            return;
        }
        // If caching this response would make the cache exceed its maximum size, evict something
        // first.
        if (lru.size >= this.config.maxSize) {
            // The cache is too big, evict something.
            const evictedUrl = lru.pop();
            if (evictedUrl !== null) {
                await this.clearCacheForUrl(evictedUrl);
            }
        }
        // TODO: evaluate for possible race conditions during flaky network periods.
        // Mark this resource as having been accessed recently. This ensures it won't be evicted
        // until enough other resources are requested that it falls off the end of the LRU chain.
        lru.accessed(req.url);
        // Store the response in the cache (cloning because the browser will consume
        // the body during the caching operation).
        await (await this.cache).put(req, res.clone());
        // Store the age of the cache.
        const ageTable = await this.ageTable;
        await ageTable.write(req.url, { age: this.adapter.time });
        // Sync the LRU chain to non-volatile storage.
        await this.syncLru();
    }
    /**
     * Delete all of the saved state which this group uses to track resources.
     */
    async cleanup() {
        // Remove both the cache and the database entries which track LRU stats.
        await Promise.all([
            this.scope.caches.delete(`${this.prefix}:dynamic:${this.config.name}:cache`),
            this.db.delete(`${this.prefix}:dynamic:${this.config.name}:age`),
            this.db.delete(`${this.prefix}:dynamic:${this.config.name}:lru`),
        ]);
    }
    /**
     * Clear the state of the cache for a particular resource.
     *
     * This doesn't remove the resource from the LRU table, that is assumed to have
     * been done already. This clears the GET and HEAD versions of the request from
     * the cache itself, as well as the metadata stored in the age table.
     */
    async clearCacheForUrl(url) {
        const [cache, ageTable] = await Promise.all([this.cache, this.ageTable]);
        await Promise.all([
            cache.delete(this.adapter.newRequest(url, { method: 'GET' })),
            cache.delete(this.adapter.newRequest(url, { method: 'HEAD' })),
            ageTable.delete(url),
        ]);
    }
    async safeFetch(req) {
        try {
            return this.scope.fetch(req);
        }
        catch (err) {
            return this.adapter.newResponse(null, {
                status: 504,
                statusText: 'Gateway Timeout',
            });
        }
    }
}

/**
 * @license
 * Copyright Google Inc. All Rights Reserved.
 *
 * Use of this source code is governed by an MIT-style license that can be
 * found in the LICENSE file at https://angular.io/license
 */
function isNavigationRequest(req, relativeTo, adapter) {
    if (req.mode !== 'navigate') {
        return false;
    }
    if (req.url.indexOf('__') !== -1) {
        return false;
    }
    if (hasFileExtension(req.url, relativeTo, adapter)) {
        return false;
    }
    if (!acceptsTextHtml(req)) {
        return false;
    }
    return true;
}
function hasFileExtension(url, relativeTo, adapter) {
    const path = adapter.parseUrl(url, relativeTo).path;
    const lastSegment = path.split('/').pop();
    return lastSegment.indexOf('.') !== -1;
}
function acceptsTextHtml(req) {
    const accept = req.headers.get('Accept');
    if (accept === null) {
        return false;
    }
    const values = accept.split(',');
    return values.some(value => value.trim().toLowerCase() === 'text/html');
}

/**
 * @license
 * Copyright Google Inc. All Rights Reserved.
 *
 * Use of this source code is governed by an MIT-style license that can be
 * found in the LICENSE file at https://angular.io/license
 */
/**
 * A specific version of the application, identified by a unique manifest
 * as determined by its hash.
 *
 * Each `AppVersion` can be thought of as a published version of the app
 * that can be installed as an update to any previously installed versions.
 */
class AppVersion {
    constructor(scope, adapter, database, idle, manifest, manifestHash) {
        this.scope = scope;
        this.adapter = adapter;
        this.database = database;
        this.idle = idle;
        this.manifest = manifest;
        this.manifestHash = manifestHash;
        /**
         * A Map of absolute URL paths (/foo.txt) to the known hash of their
         * contents (if available).
         */
        this.hashTable = new Map();
        /**
         * Tracks whether the manifest has encountered any inconsistencies.
         */
        this._okay = true;
        // The hashTable within the manifest is an Object - convert it to a Map for easier lookups.
        Object.keys(this.manifest.hashTable).forEach(url => {
            this.hashTable.set(url, this.manifest.hashTable[url]);
        });
        // Process each `AssetGroup` declared in the manifest. Each declared group gets an `AssetGroup`
        // instance
        // created for it, of a type that depends on the configuration mode.
        this.assetGroups = (manifest.assetGroups || []).map(config => {
            // Every asset group has a cache that's prefixed by the manifest hash and the name of the
            // group.
            const prefix = `ngsw:${this.manifestHash}:assets`;
            // Check the caching mode, which determines when resources will be fetched/updated.
            switch (config.installMode) {
                case 'prefetch':
                    return new PrefetchAssetGroup(this.scope, this.adapter, this.idle, config, this.hashTable, this.database, prefix);
                case 'lazy':
                    return new LazyAssetGroup(this.scope, this.adapter, this.idle, config, this.hashTable, this.database, prefix);
            }
        });
        // Process each `DataGroup` declared in the manifest.
        this.dataGroups = (manifest.dataGroups || [])
            .map(config => new DataGroup(this.scope, this.adapter, config, this.database, `ngsw:${config.version}:data`));
    }
    get okay() { return this._okay; }
    /**
     * Fully initialize this version of the application. If this Promise resolves successfully, all
     * required
     * data has been safely downloaded.
     */
    async initializeFully(updateFrom) {
        try {
            // Fully initialize each asset group, in series. Starts with an empty Promise,
            // and waits for the previous groups to have been initialized before initializing
            // the next one in turn.
            await this.assetGroups.reduce(async (previous, group) => {
                // Wait for the previous groups to complete initialization. If there is a
                // failure, this will throw, and each subsequent group will throw, until the
                // whole sequence fails.
                await previous;
                // Initialize this group.
                return group.initializeFully(updateFrom);
            }, Promise.resolve());
        }
        catch (err) {
            this._okay = false;
            throw err;
        }
    }
    async handleFetch(req, context) {
        // Check the request against each `AssetGroup` in sequence. If an `AssetGroup` can't handle the
        // request,
        // it will return `null`. Thus, the first non-null response is the SW's answer to the request.
        // So reduce
        // the group list, keeping track of a possible response. If there is one, it gets passed
        // through, and if
        // not the next group is consulted to produce a candidate response.
        const asset = await this.assetGroups.reduce(async (potentialResponse, group) => {
            // Wait on the previous potential response. If it's not null, it should just be passed
            // through.
            const resp = await potentialResponse;
            if (resp !== null) {
                return resp;
            }
            // No response has been found yet. Maybe this group will have one.
            return group.handleFetch(req, context);
        }, Promise.resolve(null));
        // The result of the above is the asset response, if there is any, or null otherwise. Return the
        // asset
        // response if there was one. If not, check with the data caching groups.
        if (asset !== null) {
            return asset;
        }
        // Perform the same reduction operation as above, but this time processing
        // the data caching groups.
        const data = await this.dataGroups.reduce(async (potentialResponse, group) => {
            const resp = await potentialResponse;
            if (resp !== null) {
                return resp;
            }
            return group.handleFetch(req, context);
        }, Promise.resolve(null));
        // If the data caching group returned a response, go with it.
        if (data !== null) {
            return data;
        }
        // Next, check if this is a navigation request for a route. Detect circular
        // navigations by checking if the request URL is the same as the index URL.
        if (isNavigationRequest(req, this.scope.registration.scope, this.adapter) &&
            req.url !== this.manifest.index) {
            // This was a navigation request. Re-enter `handleFetch` with a request for
            // the URL.
            return this.handleFetch(this.adapter.newRequest(this.manifest.index), context);
        }
        return null;
    }
    /**
     * Check this version for a given resource with a particular hash.
     */
    async lookupResourceWithHash(url, hash) {
        const req = this.adapter.newRequest(url);
        // Verify that this version has the requested resource cached. If not,
        // there's no point in trying.
        if (!this.hashTable.has(url)) {
            return null;
        }
        // Next, check whether the resource has the correct hash. If not, any cached
        // response isn't usable.
        if (this.hashTable.get(url) !== hash) {
            return null;
        }
        // TODO: no-op context and appropriate contract. Currently this is a violation
        // of the typings and could cause issues if handleFetch() has side effects. A
        // better strategy to deal with side effects is needed.
        // TODO: this could result in network fetches if the response is lazy. Refactor
        // to avoid them.
        return this.handleFetch(req, null);
    }
    /**
     * Check this version for a given resource regardless of its hash.
     */
    lookupResourceWithoutHash(url) {
        // Limit the search to asset groups, and only scan the cache, don't
        // load resources from the network.
        return this.assetGroups.reduce(async (potentialResponse, group) => {
            const resp = await potentialResponse;
            if (resp !== null) {
                return resp;
            }
            // fetchFromCacheOnly() avoids any network fetches, and returns the
            // full set of cache data, not just the Response.
            return group.fetchFromCacheOnly(url);
        }, Promise.resolve(null));
    }
    /**
     * List all unhashed resources from all asset groups.
     */
    previouslyCachedResources() {
        return this.assetGroups.reduce(async (resources, group) => {
            return (await resources).concat(await group.unhashedResources());
        }, Promise.resolve([]));
    }
    async recentCacheStatus(url) {
        return this.assetGroups.reduce(async (current, group) => {
            const status = await current;
            if (status === UpdateCacheStatus.CACHED) {
                return status;
            }
            const groupStatus = await group.cacheStatus(url);
            if (groupStatus === UpdateCacheStatus.NOT_CACHED) {
                return status;
            }
            return groupStatus;
        }, Promise.resolve(UpdateCacheStatus.NOT_CACHED));
    }
    /**
     * Erase this application version, by cleaning up all the caches.
     */
    async cleanup() {
        await Promise.all(this.assetGroups.map(group => group.cleanup()));
        await Promise.all(this.dataGroups.map(group => group.cleanup()));
    }
    /**
     * Get the opaque application data which was provided with the manifest.
     */
    get appData() { return this.manifest.appData || null; }
}

/**
 * @license
 * Copyright Google Inc. All Rights Reserved.
 *
 * Use of this source code is governed by an MIT-style license that can be
 * found in the LICENSE file at https://angular.io/license
 */
const DEBUG_LOG_BUFFER_SIZE = 100;
class DebugHandler {
    constructor(driver, adapter) {
        this.driver = driver;
        this.adapter = adapter;
        // There are two debug log message arrays. debugLogA records new debugging messages.
        // Once it reaches DEBUG_LOG_BUFFER_SIZE, the array is moved to debugLogB and a new
        // array is assigned to debugLogA. This ensures that insertion to the debug log is
        // always O(1) no matter the number of logged messages, and that the total number
        // of messages in the log never exceeds 2 * DEBUG_LOG_BUFFER_SIZE.
        this.debugLogA = [];
        this.debugLogB = [];
    }
    async handleFetch(req) {
        const [state, versions, idle] = await Promise.all([
            this.driver.debugState(),
            this.driver.debugVersions(),
            this.driver.debugIdleState(),
        ]);
        const msgState = `NGSW Debug Info:

Driver state: ${state.state} (${state.why})
Latest manifest hash: ${state.latestHash || 'none'}
Last update check: ${this.since(state.lastUpdateCheck)}`;
        const msgVersions = versions
            .map(version => `=== Version ${version.hash} ===

Clients: ${version.clients.join(', ')}`)
            .join('\n\n');
        const msgIdle = `=== Idle Task Queue ===
Last update tick: ${this.since(idle.lastTrigger)}
Last update run: ${this.since(idle.lastRun)}
Task queue:
${idle.queue.map(v => ' * ' + v).join('\n')}

Debug log:
${this.formatDebugLog(this.debugLogB)}
${this.formatDebugLog(this.debugLogA)}
`;
        return this.adapter.newResponse(`${msgState}

${msgVersions}

${msgIdle}`, { headers: this.adapter.newHeaders({ 'Content-Type': 'text/plain' }) });
    }
    since(time) {
        if (time === null) {
            return 'never';
        }
        let age = this.adapter.time - time;
        const days = Math.floor(age / 86400000);
        age = age % 86400000;
        const hours = Math.floor(age / 3600000);
        age = age % 3600000;
        const minutes = Math.floor(age / 60000);
        age = age % 60000;
        const seconds = Math.floor(age / 1000);
        const millis = age % 1000;
        return '' + (days > 0 ? `${days}d` : '') + (hours > 0 ? `${hours}h` : '') +
            (minutes > 0 ? `${minutes}m` : '') + (seconds > 0 ? `${seconds}s` : '') +
            (millis > 0 ? `${millis}u` : '');
    }
    log(value, context = '') {
        // Rotate the buffers if debugLogA has grown too large.
        if (this.debugLogA.length === DEBUG_LOG_BUFFER_SIZE) {
            this.debugLogB = this.debugLogA;
            this.debugLogA = [];
        }
        // Convert errors to string for logging.
        if (typeof value !== 'string') {
            value = this.errorToString(value);
        }
        // Log the message.
        this.debugLogA.push({ value, time: this.adapter.time, context });
    }
    errorToString(err) { return `${err.name}(${err.message}, ${err.stack})`; }
    formatDebugLog(log) {
        return log.map(entry => `[${this.since(entry.time)}] ${entry.value} ${entry.context}`)
            .join('\n');
    }
}

/**
 * @license
 * Copyright Google Inc. All Rights Reserved.
 *
 * Use of this source code is governed by an MIT-style license that can be
 * found in the LICENSE file at https://angular.io/license
 */
class IdleScheduler {
    constructor(adapter, threshold, debug) {
        this.adapter = adapter;
        this.threshold = threshold;
        this.debug = debug;
        this.queue = [];
        this.scheduled = null;
        this.empty = Promise.resolve();
        this.emptyResolve = null;
        this.lastTrigger = null;
        this.lastRun = null;
    }
    async trigger() {
        this.lastTrigger = this.adapter.time;
        if (this.queue.length === 0) {
            return;
        }
        if (this.scheduled !== null) {
            this.scheduled.cancel = true;
        }
        const scheduled = {
            cancel: false,
        };
        this.scheduled = scheduled;
        await this.adapter.timeout(this.threshold);
        if (scheduled.cancel) {
            return;
        }
        this.scheduled = null;
        await this.execute();
    }
    async execute() {
        this.lastRun = this.adapter.time;
        while (this.queue.length > 0) {
            const queue = this.queue;
            this.queue = [];
            await queue.reduce(async (previous, task) => {
                await previous;
                try {
                    await task.run();
                }
                catch (err) {
                    this.debug.log(err, `while running idle task ${task.desc}`);
                }
            }, Promise.resolve());
        }
        if (this.emptyResolve !== null) {
            this.emptyResolve();
            this.emptyResolve = null;
        }
        this.empty = Promise.resolve();
    }
    schedule(desc, run) {
        this.queue.push({ desc, run });
        if (this.emptyResolve === null) {
            this.empty = new Promise(resolve => { this.emptyResolve = resolve; });
        }
    }
    get size() { return this.queue.length; }
    get taskDescriptions() { return this.queue.map(task => task.desc); }
}

/**
 * @license
 * Copyright Google Inc. All Rights Reserved.
 *
 * Use of this source code is governed by an MIT-style license that can be
 * found in the LICENSE file at https://angular.io/license
 */
function hashManifest(manifest) {
    return sha1(JSON.stringify(manifest));
}

/**
 * @license
 * Copyright Google Inc. All Rights Reserved.
 *
 * Use of this source code is governed by an MIT-style license that can be
 * found in the LICENSE file at https://angular.io/license
 */
function isMsgCheckForUpdates(msg) {
    return msg.action === 'CHECK_FOR_UPDATES';
}
function isMsgActivateUpdate(msg) {
    return msg.action === 'ACTIVATE_UPDATE';
}

/**
 * @license
 * Copyright Google Inc. All Rights Reserved.
 *
 * Use of this source code is governed by an MIT-style license that can be
 * found in the LICENSE file at https://angular.io/license
 */
const IDLE_THRESHOLD = 5000;
const SUPPORTED_CONFIG_VERSION = 1;
const NOTIFICATION_OPTION_NAMES = [
    'actions', 'body', 'dir', 'icon', 'lang', 'renotify', 'requireInteraction', 'tag', 'vibrate',
    'data'
];
var DriverReadyState;
(function (DriverReadyState) {
    // The SW is operating in a normal mode, responding to all traffic.
    DriverReadyState[DriverReadyState["NORMAL"] = 0] = "NORMAL";
    // The SW does not have a clean installation of the latest version of the app, but older
    // cached versions are safe to use so long as they don't try to fetch new dependencies.
    // This is a degraded state.
    DriverReadyState[DriverReadyState["EXISTING_CLIENTS_ONLY"] = 1] = "EXISTING_CLIENTS_ONLY";
    // The SW has decided that caching is completely unreliable, and is forgoing request
    // handling until the next restart.
    DriverReadyState[DriverReadyState["SAFE_MODE"] = 2] = "SAFE_MODE";
})(DriverReadyState || (DriverReadyState = {}));
class Driver {
    constructor(scope, adapter, db) {
        // Set up all the event handlers that the SW needs.
        this.scope = scope;
        this.adapter = adapter;
        this.db = db;
        /**
         * Tracks the current readiness condition under which the SW is operating. This controls
         * whether the SW attempts to respond to some or all requests.
         */
        this.state = DriverReadyState.NORMAL;
        this.stateMessage = '(nominal)';
        /**
         * Tracks whether the SW is in an initialized state or not. Before initialization,
         * it's not legal to respond to requests.
         */
        this.initialized = null;
        /**
         * Maps client IDs to the manifest hash of the application version being used to serve
         * them. If a client ID is not present here, it has not yet been assigned a version.
         *
         * If a ManifestHash appears here, it is also present in the `versions` map below.
         */
        this.clientVersionMap = new Map();
        /**
         * Maps manifest hashes to instances of `AppVersion` for those manifests.
         */
        this.versions = new Map();
        /**
         * The latest version fetched from the server.
         *
         * Valid after initialization has completed.
         */
        this.latestHash = null;
        this.lastUpdateCheck = null;
        // The install event is triggered when the service worker is first installed.
        this.scope.addEventListener('install', (event) => {
            // SW code updates are separate from application updates, so code updates are
            // almost as straightforward as restarting the SW. Because of this, it's always
            // safe to skip waiting until application tabs are closed, and activate the new
            // SW version immediately.
            event.waitUntil(this.scope.skipWaiting());
        });
        // The activate event is triggered when this version of the service worker is
        // first activated.
        this.scope.addEventListener('activate', (event) => {
            // As above, it's safe to take over from existing clients immediately, since
            // the new SW version will continue to serve the old application.
            event.waitUntil(this.scope.clients.claim());
            // Rather than wait for the first fetch event, which may not arrive until
            // the next time the application is loaded, the SW takes advantage of the
            // activation event to schedule initialization. However, if this were run
            // in the context of the 'activate' event, waitUntil() here would cause fetch
            // events to block until initialization completed. Thus, the SW does a
            // postMessage() to itself, to schedule a new event loop iteration with an
            // entirely separate event context. The SW will be kept alive by waitUntil()
            // within that separate context while initialization proceeds, while at the
            // same time the activation event is allowed to resolve and traffic starts
            // being served.
            if (this.scope.registration.active !== null) {
                this.scope.registration.active.postMessage({ action: 'INITIALIZE' });
            }
        });
        // Handle the fetch, message, and push events.
        this.scope.addEventListener('fetch', (event) => this.onFetch(event));
        this.scope.addEventListener('message', (event) => this.onMessage(event));
        this.scope.addEventListener('push', (event) => this.onPush(event));
        // The debugger generates debug pages in response to debugging requests.
        this.debugger = new DebugHandler(this, this.adapter);
        // The IdleScheduler will execute idle tasks after a given delay.
        this.idle = new IdleScheduler(this.adapter, IDLE_THRESHOLD, this.debugger);
    }
    /**
     * The handler for fetch events.
     *
     * This is the transition point between the synchronous event handler and the
     * asynchronous execution that eventually resolves for respondWith() and waitUntil().
     */
    onFetch(event) {
        // The only thing that is served unconditionally is the debug page.
        if (this.adapter.parseUrl(event.request.url, this.scope.registration.scope).path ===
            '/ngsw/state') {
            // Allow the debugger to handle the request, but don't affect SW state in any
            // other way.
            event.respondWith(this.debugger.handleFetch(event.request));
            return;
        }
        // If the SW is in a broken state where it's not safe to handle requests at all,
        // returning causes the request to fall back on the network. This is preferred over
        // `respondWith(fetch(req))` because the latter still shows in DevTools that the
        // request was handled by the SW.
        // TODO: try to handle DriverReadyState.EXISTING_CLIENTS_ONLY here.
        if (this.state === DriverReadyState.SAFE_MODE) {
            // Even though the worker is in safe mode, idle tasks still need to happen so
            // things like update checks, etc. can take place.
            event.waitUntil(this.idle.trigger());
            return;
        }
        // Past this point, the SW commits to handling the request itself. This could still
        // fail (and result in `state` being set to `SAFE_MODE`), but even in that case the
        // SW will still deliver a response.
        event.respondWith(this.handleFetch(event));
    }
    /**
     * The handler for message events.
     */
    onMessage(event) {
        // Ignore message events when the SW is in safe mode, for now.
        if (this.state === DriverReadyState.SAFE_MODE) {
            return;
        }
        // If the message doesn't have the expected signature, ignore it.
        const data = event.data;
        if (!data || !data.action) {
            return;
        }
        // Initialization is the only event which is sent directly from the SW to itself,
        // and thus `event.source` is not a Client. Handle it here, before the check
        // for Client sources.
        if (data.action === 'INITIALIZE' && this.initialized === null) {
            // Initialize the SW.
            this.initialized = this.initialize();
            // Wait until initialization is properly scheduled, then trigger idle
            // events to allow it to complete (assuming the SW is idle).
            event.waitUntil((async () => {
                await this.initialized;
                await this.idle.trigger();
            })());
        }
        // Only messages from true clients are accepted past this point (this is essentially
        // a typecast).
        if (!this.adapter.isClient(event.source)) {
            return;
        }
        // Handle the message and keep the SW alive until it's handled.
        event.waitUntil(this.handleMessage(data, event.source));
    }
    onPush(msg) {
        // Push notifications without data have no effect.
        if (!msg.data) {
            return;
        }
        // Handle the push and keep the SW alive until it's handled.
        msg.waitUntil(this.handlePush(msg.data.json()));
    }
    async handleMessage(msg, from) {
        if (isMsgCheckForUpdates(msg)) {
            const action = (async () => { await this.checkForUpdate(); })();
            await this.reportStatus(from, action, msg.statusNonce);
        }
        else if (isMsgActivateUpdate(msg)) {
            await this.reportStatus(from, this.updateClient(from), msg.statusNonce);
        }
    }
    async handlePush(data) {
        this.broadcast({
            type: 'PUSH',
            data,
        });
        if (!data.notification || !data.notification.title) {
            return;
        }
        const desc = data.notification;
        let options = {};
        NOTIFICATION_OPTION_NAMES.filter(name => desc.hasOwnProperty(name))
            .forEach(name => options[name] = desc[name]);
        this.scope.registration.showNotification(desc['title'], options);
    }
    async reportStatus(client, promise, nonce) {
        const response = { type: 'STATUS', nonce, status: true };
        try {
            await promise;
            client.postMessage(response);
        }
        catch (e) {
            client.postMessage(Object.assign({}, response, { status: false, error: e.toString() }));
        }
    }
    async updateClient(client) {
        // Figure out which version the client is on. If it's not on the latest,
        // it needs to be moved.
        const existing = this.clientVersionMap.get(client.id);
        if (existing === this.latestHash) {
            // Nothing to do, this client is already on the latest version.
            return;
        }
        // Switch the client over.
        let previous = undefined;
        // Look up the application data associated with the existing version. If there
        // isn't any, fall back on using the hash.
        if (existing !== undefined) {
            const existingVersion = this.versions.get(existing);
            previous = this.mergeHashWithAppData(existingVersion.manifest, existing);
        }
        // Set the current version used by the client, and sync the mapping to disk.
        this.clientVersionMap.set(client.id, this.latestHash);
        await this.sync();
        // Notify the client about this activation.
        const current = this.versions.get(this.latestHash);
        const notice = {
            type: 'UPDATE_ACTIVATED',
            previous,
            current: this.mergeHashWithAppData(current.manifest, this.latestHash),
        };
        client.postMessage(notice);
    }
    async handleFetch(event) {
        // Since the SW may have just been started, it may or may not have been initialized already.
        // this.initialized will be `null` if initialization has not yet been attempted, or will be a
        // Promise which will resolve (successfully or unsuccessfully) if it has.
        if (this.initialized === null) {
            // Initialization has not yet been attempted, so attempt it. This should only ever happen once
            // per SW instantiation.
            this.initialized = this.initialize();
        }
        // If initialization fails, the SW needs to enter a safe state, where it declines to respond to
        // network requests.
        try {
            // Wait for initialization.
            await this.initialized;
        }
        catch (e) {
            // Initialization failed. Enter a safe state.
            this.state = DriverReadyState.SAFE_MODE;
            this.stateMessage = `Initialization failed due to error: ${errorToString(e)}`;
            // Even though the driver entered safe mode, background tasks still need to happen.
            event.waitUntil(this.idle.trigger());
            // Since the SW is already committed to responding to the currently active request,
            // respond with a network fetch.
            return this.safeFetch(event.request);
        }
        // Decide which version of the app to use to serve this request. This is asynchronous as in
        // some cases, a record will need to be written to disk about the assignment that is made.
        const appVersion = await this.assignVersion(event);
        // Bail out
        if (appVersion === null) {
            event.waitUntil(this.idle.trigger());
            return this.safeFetch(event.request);
        }
        // Handle the request. First try the AppVersion. If that doesn't work, fall back on the network.
        const res = await appVersion.handleFetch(event.request, event);
        // The AppVersion will only return null if the manifest doesn't specify what to do about this
        // request. In that case, just fall back on the network.
        if (res === null) {
            event.waitUntil(this.idle.trigger());
            return this.safeFetch(event.request);
        }
        // Trigger the idle scheduling system. The Promise returned by trigger() will resolve after
        // a specific amount of time has passed. If trigger() hasn't been called again by then (e.g.
        // on a subsequent request), the idle task queue will be drained and the Promise won't resolve
        // until that operation is complete as well.
        event.waitUntil(this.idle.trigger());
        // The AppVersion returned a usable response, so return it.
        return res;
    }
    /**
     * Attempt to quickly reach a state where it's safe to serve responses.
     */
    async initialize() {
        // On initialization, all of the serialized state is read out of the 'control'
        // table. This includes:
        // - map of hashes to manifests of currently loaded application versions
        // - map of client IDs to their pinned versions
        // - record of the most recently fetched manifest hash
        //
        // If these values don't exist in the DB, then this is the either the first time
        // the SW has run or the DB state has been wiped or is inconsistent. In that case,
        // load a fresh copy of the manifest and reset the state from scratch.
        // Open up the DB table.
        const table = await this.db.open('control');
        // Attempt to load the needed state from the DB. If this fails, the catch {} block
        // will populate these variables with freshly constructed values.
        let manifests, assignments, latest;
        try {
            // Read them from the DB simultaneously.
            [manifests, assignments, latest] = await Promise.all([
                table.read('manifests'),
                table.read('assignments'),
                table.read('latest'),
            ]);
            // Successfully loaded from saved state. This implies a manifest exists, so
            // the update check needs to happen in the background.
            this.idle.schedule('init post-load (update, cleanup)', async () => {
                await this.checkForUpdate();
                try {
                    await this.cleanupCaches();
                }
                catch (err) {
                    // Nothing to do - cleanup failed. Just log it.
                    this.debugger.log(err, 'cleanupCaches @ init post-load');
                }
            });
        }
        catch (_) {
            // Something went wrong. Try to start over by fetching a new manifest from the
            // server and building up an empty initial state.
            const manifest = await this.fetchLatestManifest();
            const hash = hashManifest(manifest);
            manifests = {};
            manifests[hash] = manifest;
            assignments = {};
            latest = { latest: hash };
            // Save the initial state to the DB.
            await Promise.all([
                table.write('manifests', manifests),
                table.write('assignments', assignments),
                table.write('latest', latest),
            ]);
        }
        // At this point, either the state has been loaded successfully, or fresh state
        // with a new copy of the manifest has been produced. At this point, the `Driver`
        // can have its internals hydrated from the state.
        // Initialize the `versions` map by setting each hash to a new `AppVersion` instance
        // for that manifest.
        Object.keys(manifests).forEach((hash) => {
            const manifest = manifests[hash];
            // If the manifest is newly initialized, an AppVersion may have already been
            // created for it.
            if (!this.versions.has(hash)) {
                this.versions.set(hash, new AppVersion(this.scope, this.adapter, this.db, this.idle, manifest, hash));
            }
        });
        // Map each client ID to its associated hash. Along the way, verify that the hash
        // is still valid for that client ID. It should not be possible for a client to
        // still be associated with a hash that was since removed from the state.
        Object.keys(assignments).forEach((clientId) => {
            const hash = assignments[clientId];
            if (this.versions.has(hash)) {
                this.clientVersionMap.set(clientId, hash);
            }
            else {
                this.clientVersionMap.set(clientId, latest.latest);
                this.debugger.log(`Unknown version ${hash} mapped for client ${clientId}, using latest instead`, `initialize: map assignments`);
            }
        });
        // Set the latest version.
        this.latestHash = latest.latest;
        // Finally, assert that the latest version is in fact loaded.
        if (!this.versions.has(latest.latest)) {
            throw new Error(`Invariant violated (initialize): latest hash ${latest.latest} has no known manifest`);
        }
        // Finally, wait for the scheduling of initialization of all versions in the
        // manifest. Ordinarily this just schedules the initializations to happen during
        // the next idle period, but in development mode this might actually wait for the
        // full initialization.
        // If any of these initializations fail, versionFailed() will be called either
        // synchronously or asynchronously to handle the failure and re-map clients.
        await Promise.all(Object.keys(manifests).map(async (hash) => {
            try {
                // Attempt to schedule or initialize this version. If this operation is
                // successful, then initialization either succeeded or was scheduled. If
                // it fails, then full initialization was attempted and failed.
                await this.scheduleInitialization(this.versions.get(hash));
            }
            catch (err) {
                this.debugger.log(err, `initialize: schedule init of ${hash}`);
                return false;
            }
        }));
    }
    lookupVersionByHash(hash, debugName = 'lookupVersionByHash') {
        // The version should exist, but check just in case.
        if (!this.versions.has(hash)) {
            throw new Error(`Invariant violated (${debugName}): want AppVersion for ${hash} but not loaded`);
        }
        return this.versions.get(hash);
    }
    /**
     * Decide which version of the manifest to use for the event.
     */
    async assignVersion(event) {
        // First, check whether the event has a client ID. If it does, the version may
        // already be associated.
        const clientId = event.clientId;
        if (clientId !== null) {
            // Check if there is an assigned client id.
            if (this.clientVersionMap.has(clientId)) {
                // There is an assignment for this client already.
                let hash = this.clientVersionMap.get(clientId);
                // Ordinarily, this client would be served from its assigned version. But, if this
                // request is a navigation request, this client can be updated to the latest
                // version immediately.
                if (this.state === DriverReadyState.NORMAL && hash !== this.latestHash &&
                    isNavigationRequest(event.request, this.scope.registration.scope, this.adapter)) {
                    // Update this client to the latest version immediately.
                    if (this.latestHash === null) {
                        throw new Error(`Invariant violated (assignVersion): latestHash was null`);
                    }
                    const client = await this.scope.clients.get(clientId);
                    await this.updateClient(client);
                    hash = this.latestHash;
                }
                // TODO: make sure the version is valid.
                return this.lookupVersionByHash(hash, 'assignVersion');
            }
            else {
                // This is the first time this client ID has been seen. Whether the SW is in a
                // state to handle new clients depends on the current readiness state, so check
                // that first.
                if (this.state !== DriverReadyState.NORMAL) {
                    // It's not safe to serve new clients in the current state. It's possible that
                    // this is an existing client which has not been mapped yet (see below) but
                    // even if that is the case, it's invalid to make an assignment to a known
                    // invalid version, even if that assignment was previously implicit. Return
                    // undefined here to let the caller know that no assignment is possible at
                    // this time.
                    return null;
                }
                // It's safe to handle this request. Two cases apply. Either:
                // 1) the browser assigned a client ID at the time of the navigation request, and
                //    this is truly the first time seeing this client, or
                // 2) a navigation request came previously from the same client, but with no client
                //    ID attached. Browsers do this to avoid creating a client under the origin in
                //    the event the navigation request is just redirected.
                //
                // In case 1, the latest version can safely be used.
                // In case 2, the latest version can be used, with the assumption that the previous
                // navigation request was answered under the same version. This assumption relies
                // on the fact that it's unlikely an update will come in between the navigation
                // request and requests for subsequent resources on that page.
                // First validate the current state.
                if (this.latestHash === null) {
                    throw new Error(`Invariant violated (assignVersion): latestHash was null`);
                }
                // Pin this client ID to the current latest version, indefinitely.
                this.clientVersionMap.set(clientId, this.latestHash);
                await this.sync();
                // Return the latest `AppVersion`.
                return this.lookupVersionByHash(this.latestHash, 'assignVersion');
            }
        }
        else {
            // No client ID was associated with the request. This must be a navigation request
            // for a new client. First check that the SW is accepting new clients.
            if (this.state !== DriverReadyState.NORMAL) {
                return null;
            }
            // Serve it with the latest version, and assume that the client will actually get
            // associated with that version on the next request.
            // First validate the current state.
            if (this.latestHash === null) {
                throw new Error(`Invariant violated (assignVersion): latestHash was null`);
            }
            // Return the latest `AppVersion`.
            return this.lookupVersionByHash(this.latestHash, 'assignVersion');
        }
    }
    /**
     * Retrieve a copy of the latest manifest from the server.
     */
    async fetchLatestManifest() {
        const res = await this.safeFetch(this.adapter.newRequest('/ngsw.json?ngsw-cache-bust=' + Math.random()));
        if (!res.ok) {
            if (res.status === 404) {
                await this.deleteAllCaches();
                this.scope.registration.unregister();
            }
            throw new Error('Manifest fetch failed!');
        }
        this.lastUpdateCheck = this.adapter.time;
        return res.json();
    }
    async deleteAllCaches() {
        await (await this.scope.caches.keys())
            .filter(key => key.startsWith('ngsw:'))
            .reduce(async (previous, key) => {
            await Promise.all([
                previous,
                this.scope.caches.delete(key),
            ]);
        }, Promise.resolve());
    }
    /**
     * Schedule the SW's attempt to reach a fully prefetched state for the given AppVersion
     * when the SW is not busy and has connectivity. This returns a Promise which must be
     * awaited, as under some conditions the AppVersion might be initialized immediately.
     */
    async scheduleInitialization(appVersion) {
        const initialize = async () => {
            try {
                await appVersion.initializeFully();
            }
            catch (err) {
                this.debugger.log(err, `initializeFully for ${appVersion.manifestHash}`);
                await this.versionFailed(appVersion, err);
            }
        };
        // TODO: better logic for detecting localhost.
        if (this.scope.registration.scope.indexOf('://localhost') > -1) {
            return initialize();
        }
        this.idle.schedule(`initialization(${appVersion.manifestHash})`, initialize);
    }
    async versionFailed(appVersion, err) {
        // This particular AppVersion is broken. First, find the manifest hash.
        const broken = Array.from(this.versions.entries()).find(([hash, version]) => version === appVersion);
        if (broken === undefined) {
            // This version is no longer in use anyway, so nobody cares.
            return;
        }
        const brokenHash = broken[0];
        // TODO: notify affected apps.
        // The action taken depends on whether the broken manifest is the active (latest) or not.
        // If so, the SW cannot accept new clients, but can continue to service old ones.
        if (this.latestHash === brokenHash) {
            // The latest manifest is broken. This means that new clients are at the mercy of the
            // network, but caches continue to be valid for previous versions. This is
            // unfortunate but unavoidable.
            this.state = DriverReadyState.EXISTING_CLIENTS_ONLY;
            this.stateMessage = `Degraded due to failed initialization: ${errorToString(err)}`;
            // Cancel the binding for these clients.
            Array.from(this.clientVersionMap.keys())
                .forEach(clientId => this.clientVersionMap.delete(clientId));
        }
        else {
            // The current version is viable, but this older version isn't. The only
            // possible remedy is to stop serving the older version and go to the network.
            // Figure out which clients are affected and put them on the latest.
            const affectedClients = Array.from(this.clientVersionMap.keys())
                .filter(clientId => this.clientVersionMap.get(clientId) === brokenHash);
            // Push the affected clients onto the latest version.
            affectedClients.forEach(clientId => this.clientVersionMap.set(clientId, this.latestHash));
        }
        await this.sync();
    }
    async setupUpdate(manifest, hash) {
        const newVersion = new AppVersion(this.scope, this.adapter, this.db, this.idle, manifest, hash);
        // Try to determine a version that's safe to update from.
        let updateFrom = undefined;
        // It's always safe to update from a version, even a broken one, as it will still
        // only have valid resources cached. If there is no latest version, though, this
        // update will have to install as a fresh version.
        if (this.latestHash !== null) {
            updateFrom = this.versions.get(this.latestHash);
        }
        // Firstly, check if the manifest version is correct.
        if (manifest.configVersion !== SUPPORTED_CONFIG_VERSION) {
            await this.deleteAllCaches();
            this.scope.registration.unregister();
            throw new Error(`Invalid config version: expected ${SUPPORTED_CONFIG_VERSION}, got ${manifest.configVersion}.`);
        }
        // Cause the new version to become fully initialized. If this fails, then the
        // version will not be available for use.
        await newVersion.initializeFully(this);
        // Install this as an active version of the app.
        this.versions.set(hash, newVersion);
        // Future new clients will use this hash as the latest version.
        this.latestHash = hash;
        await this.sync();
        await this.notifyClientsAboutUpdate();
    }
    async checkForUpdate() {
        try {
            const manifest = await this.fetchLatestManifest();
            const hash = hashManifest(manifest);
            // Check whether this is really an update.
            if (this.versions.has(hash)) {
                return false;
            }
            await this.setupUpdate(manifest, hash);
            return true;
        }
        catch (_) {
            return false;
        }
    }
    /**
     * Synchronize the existing state to the underlying database.
     */
    async sync() {
        // Open up the DB table.
        const table = await this.db.open('control');
        // Construct a serializable map of hashes to manifests.
        const manifests = {};
        this.versions.forEach((version, hash) => { manifests[hash] = version.manifest; });
        // Construct a serializable map of client ids to version hashes.
        const assignments = {};
        this.clientVersionMap.forEach((hash, clientId) => { assignments[clientId] = hash; });
        // Record the latest entry. Since this is a sync which is necessarily happening after
        // initialization, latestHash should always be valid.
        const latest = {
            latest: this.latestHash,
        };
        // Synchronize all of these.
        await Promise.all([
            table.write('manifests', manifests),
            table.write('assignments', assignments),
            table.write('latest', latest),
        ]);
    }
    async cleanupCaches() {
        // Query for all currently active clients, and list the client ids. This may skip
        // some clients in the browser back-forward cache, but not much can be done about
        // that.
        const activeClients = (await this.scope.clients.matchAll()).map(client => client.id);
        // A simple list of client ids that the SW has kept track of. Subtracting
        // activeClients from this list will result in the set of client ids which are
        // being tracked but are no longer used in the browser, and thus can be cleaned up.
        const knownClients = Array.from(this.clientVersionMap.keys());
        // Remove clients in the clientVersionMap that are no longer active.
        knownClients.filter(id => activeClients.indexOf(id) === -1)
            .forEach(id => this.clientVersionMap.delete(id));
        // Next, determine the set of versions which are still used. All others can be
        // removed.
        const usedVersions = new Set();
        this.clientVersionMap.forEach((version, _) => usedVersions.add(version));
        // Collect all obsolete versions by filtering out used versions from the set of all versions.
        const obsoleteVersions = Array.from(this.versions.keys())
            .filter(version => !usedVersions.has(version) && version !== this.latestHash);
        // Remove all the versions which are no longer used.
        await obsoleteVersions.reduce(async (previous, version) => {
            // Wait for the other cleanup operations to complete.
            await previous;
            // Try to get past the failure of one particular version to clean up (this
            // shouldn't happen, but handle it just in case).
            try {
                // Get ahold of the AppVersion for this particular hash.
                const instance = this.versions.get(version);
                // Delete it from the canonical map.
                this.versions.delete(version);
                // Clean it up.
                await instance.cleanup();
            }
            catch (err) {
                // Oh well? Not much that can be done here. These caches will be removed when
                // the SW revs its format version, which happens from time to time.
                this.debugger.log(err, `cleanupCaches - cleanup ${version}`);
            }
        }, Promise.resolve());
        // Commit all the changes to the saved state.
        await this.sync();
    }
    /**
     * Determine if a specific version of the given resource is cached anywhere within the SW,
     * and fetch it if so.
     */
    lookupResourceWithHash(url, hash) {
        return Array
            .from(this.versions.values())
            .reduce(async (prev, version) => {
            // First, check the previous result. If a non-null result has been found already, just
            // return it.
            if (await prev !== null) {
                return prev;
            }
            // No result has been found yet. Try the next `AppVersion`.
            return version.lookupResourceWithHash(url, hash);
        }, Promise.resolve(null));
    }
    async lookupResourceWithoutHash(url) {
        await this.initialized;
        const version = this.versions.get(this.latestHash);
        return version.lookupResourceWithoutHash(url);
    }
    async previouslyCachedResources() {
        await this.initialized;
        const version = this.versions.get(this.latestHash);
        return version.previouslyCachedResources();
    }
    recentCacheStatus(url) {
        const version = this.versions.get(this.latestHash);
        return version.recentCacheStatus(url);
    }
    mergeHashWithAppData(manifest, hash) {
        return {
            hash,
            appData: manifest.appData,
        };
    }
    async notifyClientsAboutUpdate() {
        await this.initialized;
        const clients = await this.scope.clients.matchAll();
        const next = this.versions.get(this.latestHash);
        await clients.reduce(async (previous, client) => {
            await previous;
            // Firstly, determine which version this client is on.
            const version = this.clientVersionMap.get(client.id);
            if (version === undefined) {
                // Unmapped client - assume it's the latest.
                return;
            }
            if (version === this.latestHash) {
                // Client is already on the latest version, no need for a notification.
                return;
            }
            const current = this.versions.get(version);
            // Send a notice.
            const notice = {
                type: 'UPDATE_AVAILABLE',
                current: this.mergeHashWithAppData(current.manifest, version),
                available: this.mergeHashWithAppData(next.manifest, this.latestHash),
            };
            client.postMessage(notice);
        }, Promise.resolve());
    }
    async broadcast(msg) {
        const clients = await this.scope.clients.matchAll();
        clients.forEach(client => { client.postMessage(msg); });
    }
    async debugState() {
        return {
            state: DriverReadyState[this.state],
            why: this.stateMessage,
            latestHash: this.latestHash,
            lastUpdateCheck: this.lastUpdateCheck,
        };
    }
    async debugVersions() {
        // Build list of versions.
        return Array.from(this.versions.keys()).map(hash => {
            const version = this.versions.get(hash);
            const clients = Array.from(this.clientVersionMap.entries())
                .filter(([clientId, version]) => version === hash)
                .map(([clientId, version]) => clientId);
            return {
                hash,
                manifest: version.manifest, clients,
                status: '',
            };
        });
    }
    async debugIdleState() {
        return {
            queue: this.idle.taskDescriptions,
            lastTrigger: this.idle.lastTrigger,
            lastRun: this.idle.lastRun,
        };
    }
    async safeFetch(req) {
        try {
            return await this.scope.fetch(req);
        }
        catch (err) {
            this.debugger.log(err, `Driver.fetch(${req.url})`);
            return this.adapter.newResponse(null, {
                status: 504,
                statusText: 'Gateway Timeout',
            });
        }
    }
}
function errorToString(error) {
    if (error instanceof Error) {
        return `${error.message}\n${error.stack}`;
    }
    else {
        return `${error}`;
    }
}

/**
 * @license
 * Copyright Google Inc. All Rights Reserved.
 *
 * Use of this source code is governed by an MIT-style license that can be
 * found in the LICENSE file at https://angular.io/license
 */
const scope = self;
const adapter = new Adapter();
const driver = new Driver(scope, adapter, new CacheDatabase(scope, adapter));

}());