import { Actor } from "./actor.js";
import { Action } from "./action.js";

const params = {
  mintingRatio: 1, // c1
  stakeForWin: 0.5, // c2
  stakeForAuthor: 0.5, // c3
  winningRatio: 0.5, // c4
  quorum: 1, // c5
  activeVoterThreshold: null, // c6
  voteDuration: { // c7
    min: 0,
    max: null,
  },
  // NOTE: c8 is the token loss ratio, which is specified as a runtime argument
  contentiousDebate: {
    period: 5000, // c9
    stages: 3, // c10
  },
  lockingTimeExponent: 0, // c11
};

function getTokenLossRatio(elapsed) {
  let stageDuration = params.contentiousDebate.period / 2;
  let stage = 0;
  let t = 0;
  while (true) {
    t += stageDuration;
    stageDuration /= 2;
    if (t > elapsed) {
      break;
    }
    stage += 1;
    if (stage >= params.contentiousDebate.stages - 1) {
      break;
    }
  }
  return stage / (params.contentiousDebate.stages - 1);
}

class Voter {
  constructor(reputationPublicKey) {
    this.reputationPublicKey = reputationPublicKey;
    this.voteHistory = [];
    this.reputation = 0;
    this.dateLastVote = null;
  }

  addVoteRecord(vote) {
    this.voteHistory.push(vote);
    if (!this.dateLastVote || vote.dateStart > this.dateLastVote) {
      this.dateLastVote = vote.dateStart;
    }
  }

  getReputation() {
    return this.reputation;
  }
}

class Vote {
  constructor(validationPool, {fee, duration, tokenLossRatio, contentiousDebate = false}) {
    if (tokenLossRatio < 0 || tokenLossRatio > 1) {
      throw new Error(`Token loss ratio must be in the range [0, 1]; got ${tokenLossRatio}`)
    }
    if (duration < params.voteDuration.min || duration > params.voteDuration.max) {
      throw new Error(`Duration must be in the range [${params.voteDuration.min}, ${params.voteDuration.max ?? 'Inf'}]; got ${duration}`);
    }
    this.votes = new Map();
    this.voters = new Map();
    this.validationPool = validationPool;
    this.id = window.crypto.randomUUID();
    this.dateStart = new Date();
    this.fee = fee;
    this.duration = duration;
    this.tokenLossRatio = tokenLossRatio;
    this.contentiousDebate = contentiousDebate;

    this.tokens = {
      win: fee * params.mintingRatio * params.stakeForWin,
      lose: fee * params.mintingRatio * (1 - params.stakeForWin),
      author: fee * params.mintingRatio * params.stakeForAuthor,
    }
  }

  castVote(signingPublicKey, position, stake, lockingTime) {
    if (this.duration && new Date() - this.dateStart > this.duration) {
      throw new Error(`Vote ${this.id} has expired, no new votes may be cast`);
    }
    this.votes.set(signingPublicKey, { position, stake, lockingTime });
  }

  revealIdentity(signingPublicKey, voter) {
    if (!this.votes.get(signingPublicKey)) {
      throw new Error("Must vote before revealing identity");
    }
    this.voters.set(signingPublicKey, voter);
    if (this.votes.size === this.voters.size) {
      // All voters have revealed their reputation public keys
      // Now we can evaluate winning conditions
      this.applyTokenLocking();
      this.evaluateWinningConditions();
    }
  }

  getTokenLossRatio() {
    if (!this.contentiousDebate) {
      return this.tokenLossRatio;
    }
    const elapsed = new Date() - this.dateStart;
    let stageDuration = params.contentiousDebate.period / 2;
    let stage = 0;
    let t = 0;
    while (true) {
      t += stageDuration;
      stageDuration /= 2;
      if (t > elapsed) {
        break;
      }
      stage += 1;
      if (stage >= params.contentiousDebate.stages - 1) {
        break;
      }
    }
    return stage / (params.contentiousDebate.stages - 1);
  }

  applyTokenLocking() {
    // Before evaluating the winning conditions,
    // we need to make sure any staked tokens are locked for the
    // specified amounts of time.
    // TODO: Implement token locking
  }

  evaluateWinningConditions() {
    let upvotes = 0;
    let downvotes = 0;

    for (const {position, stake, lockingTime} of this.votes.values()) {
      const value = stake * Math.pow(lockingTime, params.lockingTimeExponent);
      if (position === true) {
        upvotes += value;
      } else {
        downvotes += value;
      }
    }

    const activeVoterCount = this.validationPool.countActiveVoters();
    const votePasses = upvotes >= params.winningRatio * downvotes;
    const quorumMet = upvotes + downvotes >= params.quorum * activeVoterCount;

    if (votePasses && quorumMet) {

    }
  }

  listVoters() {
    return Array.from(this.voters.values());
  }
}

export class ValidationPool extends Actor {
  constructor(name, scene) {
    super(name, scene);
    this.votes = [];
    this.voters = new Map();

    this.actions = {
      initializeVote: new Action('initialize vote', scene),
    };
  }

  listVotes() {
    Array.from(this.votes.values());
  }

  listActiveVoters() {
    const now = new Date();
    return Array.from(this.voters.values()).filter(voter => {
      if (!params.activeVoterThreshold) {
        return true;
      }
      if (!voter.dateLastVote) {
        return false;
      }
      return now - voter.dateLastVote >= params.activeVoterThreshold;
    });
  }

  countActiveVoters() {
    return this.listActiveVoters().length;
  }

  initiateVote({fee, duration, tokenLossRatio, contentiousDebate}) {
    const vote = new Vote(this, {fee, duration, tokenLossRatio, contentiousDebate});
    this.actions.initializeVote.log(this, this);
    this.votes.set(vote.id, vote);
    return vote.id;
  }

  castVote(voteId, signingPublicKey, position, stake, lockingTime) {
    // TODO: Implement vote encryption
    const vote = this.votes.get(voteId);
    vote.castVote(signingPublicKey, position, stake, lockingTime);
  }

  revealIdentity(voteId, signingPublicKey, reputationPublicKey) {
    const vote = this.votes.get(voteId);
    const voter = this.voters.get(reputationPublicKey) ?? new Voter(reputationPublicKey);
    voter.addVoteRecord(vote);
    this.voters.set(reputationPublicKey, voter);
    vote.revealIdentity(signingPublicKey, voter);
  }
}