Voting Contract

Overview

This smart contract provides a simple voting system where users can add candidates, cast votes, and determine the winner based on the highest number of votes. It is designed to be deployed on a blockchain that supports Clarity smart contracts.

Features

• Add Candidates: Register new candidates with a unique identifier and name.
• Cast Votes: Vote for existing candidates.
• Get Candidates: Retrieve a list of all candidates and their vote counts.
• Get Votes: Retrieve the number of votes for a specific candidate.
• Get Winner: Determine the candidate with the most votes.
• Get Total Votes: Retrieve the total number of votes cast across all candidates.

Contract Functions

get-candidates

Description: Returns a list of all candidates and their vote counts.

Returns: A list of tuples where each tuple contains the candidate ID, name, and vote count.

(define-read-only (get-candidates)
  (ok (map-to-list (var-get candidates))))

get-votes (candidate u256)

Description: Returns the number of votes for a specific candidate.

Parameters:

• candidate: The unique identifier of the candidate.

Returns: The number of votes for the specified candidate, or an error message if the candidate does not exist.

(define-read-only (get-votes (candidate u256))
  (match (map-get (var-get candidates) candidate)
    ((some (tuple _ votes)) (ok votes))
    (none (err "Candidate not found"))))

add-candidate (candidate u256) (name string)

Description: Adds a new candidate to the system. The candidate must have a unique identifier.

Parameters:

• candidate: The unique identifier for the new candidate.
• name: The name of the new candidate.

Returns: A success message if the candidate was added, or an error message if the candidate already exists.

(define-private (add-candidate (candidate u256) (name string))
  (if (map-contains? (var-get candidates) candidate)
    (err "Candidate already exists")
    (begin
      (map-set candidates candidate (tuple name 0))
      (ok "Candidate added"))))

cast-vote (candidate u256)

Description: Casts a vote for a specific candidate.

Parameters:

• candidate: The unique identifier of the candidate to vote for.

Returns: A success message if the vote was cast, or an error message if the candidate does not exist.

(define-private (cast-vote (candidate u256))
  (match (map-get (var-get candidates) candidate)
    ((some (tuple name votes))
      (map-set candidates candidate (tuple name (+ votes 1)))
      (ok "Vote cast"))
    (none (err "Candidate not found"))))

get-winner

Description: Determines the candidate with the highest number of votes.

Returns: The ID of the candidate with the most votes, or an error message if no candidates are found.

(define-read-only (get-winner)
  (let ((winner (reduce-map (var-get candidates) (tuple u256 0) (lambda (k v acc)
    (if (> (tuple-get v 1) (tuple-get acc 1))
      (tuple k (tuple-get v 1))
      acc)))))
    (match winner
      ((tuple id _)) (ok id)
      _ (err "No candidates found"))))

get-total-votes

Description: Returns the total number of votes cast across all candidates.

Returns: The total number of votes.

(define-read-only (get-total-votes)
  (let ((total (reduce-map (var-get candidates) 0 (lambda (k v acc)
    (+ acc (tuple-get v 1))))))
    (ok total)))

Usage

1. Deploy the Contract: Deploy the smart contract to the blockchain platform of your choice that supports Clarity.

2. Add Candidates: Use the add-candidate function to add new candidates with unique IDs and names.

3. Cast Votes: Use the cast-vote function to vote for candidates using their unique IDs.

4. Retrieve Information: Use get-candidates, get-votes, get-winner, and get-total-votes functions to retrieve information about candidates, vote counts, and overall voting statistics.

License

This project is licensed under the MIT License.