feat: save debug logs to file

app/build.gradle

@@ -10,8 +10,8 @@ android {
         applicationId 'com.cafeed28.omori'
         minSdk 26
         targetSdk 34
-        versionCode 4
-        versionName '1.2.0'
+        versionCode 5
+        versionName '1.2.1'
     }
 
     buildTypes {

app/src/main/java/com/cafeed28/omori/Debug.java

@@ -0,0 +1,101 @@
+package com.cafeed28.omori;
+
+import android.content.Context;
+import android.os.Environment;
+import android.util.Log;
+import android.widget.Toast;
+
+import java.io.BufferedWriter;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.io.PrintWriter;
+import java.nio.file.Files;
+import java.nio.file.Paths;
+import java.text.DateFormat;
+import java.util.Date;
+
+public class Debug {
+    private final String TAG = "omori";
+
+    private final DateFormat mDateFormat = DateFormat.getDateTimeInstance(DateFormat.SHORT, DateFormat.SHORT);
+    private final String mInternalFileName;
+    private final String mExternalFileName = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOCUMENTS) + "/omori.log";
+    private final PrintWriter mPrintWriter;
+
+    private static Debug mInstance = null;
+
+    public static Debug i() {
+        return mInstance;
+    }
+
+    public Debug(String filesPath) throws IOException {
+        mInternalFileName = filesPath + "/debug.log";
+        var fileWriter = new FileWriter(mInternalFileName, true);
+        var bufferedWriter = new BufferedWriter(fileWriter);
+        mPrintWriter = new PrintWriter(bufferedWriter);
+        mPrintWriter.flush();
+        mInstance = this;
+    }
+
+    public void log(int level, String format, Object... args) {
+        String logLine;
+        try {
+            if (args.length > 0) logLine = String.format(format, args);
+            else logLine = format;
+        } catch (IllegalArgumentException e) {
+            logLine = format;
+        }
+
+        final String levelName;
+        switch (level) {
+            case Log.VERBOSE:
+                Log.v(TAG, logLine);
+                levelName = "VERBOSE";
+                break;
+            case Log.DEBUG:
+                Log.d(TAG, logLine);
+                levelName = "DEBUG";
+                break;
+            case Log.INFO:
+                Log.i(TAG, logLine);
+                levelName = "INFO";
+                break;
+            case Log.WARN:
+                Log.w(TAG, logLine);
+                levelName = "WARN";
+                break;
+            case Log.ERROR:
+                Log.e(TAG, logLine);
+                levelName = "ERROR";
+                break;
+            default:
+                throw new IllegalArgumentException();
+        }
+
+        String dateLine = String.format("[%s] %s: %s", mDateFormat.format(new Date()), levelName, logLine);
+        mPrintWriter.println(dateLine);
+        mPrintWriter.flush();
+    }
+
+    public void clear(Context context) {
+        try {
+            Files.deleteIfExists(Paths.get(mInternalFileName));
+        } catch (IOException e) {
+            Toast.makeText(context, "Failed to clear logs, check 'adb logcat' for more info", Toast.LENGTH_LONG).show();
+            this.log(Log.ERROR, "Failed to clear logs from '%s'", mInternalFileName);
+            e.printStackTrace();
+        }
+    }
+
+    public void save(Context context) {
+        try {
+            clear(context);
+            Files.copy(Paths.get(mInternalFileName), Paths.get(mExternalFileName));
+            Toast.makeText(context, String.format("Logs saved in %s", mExternalFileName), Toast.LENGTH_LONG).show();
+        } catch (IOException e) {
+            Toast.makeText(context, "Failed to save logs, check 'adb logcat' for more info", Toast.LENGTH_LONG).show();
+            this.log(Log.ERROR, "Failed to save logs to '%s'", mExternalFileName);
+            e.printStackTrace();
+        }
+    }
+}

app/src/main/java/com/cafeed28/omori/MainActivity.java

@@ -3,13 +3,24 @@
 import android.content.Intent;
 import android.os.Bundle;
 import android.widget.Button;
+import android.widget.Toast;
 
 import androidx.appcompat.app.AppCompatActivity;
 import androidx.preference.PreferenceManager;
 
+import java.io.IOException;
+
 public class MainActivity extends AppCompatActivity {
     @Override
     protected void onCreate(Bundle savedInstanceState) {
+        try {
+            new Debug(getFilesDir().getAbsolutePath());
+        } catch (IOException e) {
+            e.printStackTrace();
+            Toast.makeText(this, "Fatal error: failed to init logging", Toast.LENGTH_LONG).show();
+            finish();
+        }
+
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_main);