'use strict';

const crypto = require('crypto');
const config = require('./config');
const Blinds = require('../public/assets/blinds');

// 進行フェーズ。プレイ処理は未実装なので、ホストが手動で進めるスタブ。
const HAND_PHASES = ['PREFLOP', 'FLOP', 'TURN', 'RIVER', 'SHOWDOWN'];

class Table {
  constructor(opts) {
    this.id = opts.id;
    this.name = opts.name;
    this.startingStack = opts.startingStack;
    this.baseSmallBlind = opts.smallBlind;
    this.baseBigBlind = opts.bigBlind;
    this.timerEnabled = opts.blindTimerEnabled;
    this.intervalMin = opts.blindIntervalMin;
    this.hostToken = opts.hostToken || null;
    this.maxSeats = config.MAX_SEATS;

    this.seats = new Array(this.maxSeats).fill(null); // { token, name, stack }
    this.phase = 'WAITING';
    this.started = false;
    this.paused = false;
    this.level = 1;
    this.handNumber = 0;
    this.pot = 0;
    this.buttonSeat = null;
    this.levelEndsAt = null;
    this.levelRemainingMs = this.intervalMs;

    this.createdAt = Date.now();
    this.emptySince = null;
  }

  get intervalMs() {
    return this.intervalMin * 60 * 1000;
  }

  get blinds() {
    return Blinds.blindsAt(this.baseSmallBlind, this.baseBigBlind, this.level);
  }

  get playerCount() {
    return this.seats.filter(Boolean).length;
  }

  seatOf(token) {
    return this.seats.findIndex((s) => s && s.token === token);
  }

  isHost(token) {
    return Boolean(token) && token === this.hostToken;
  }

  // 着席した席番号を返す。満席なら -1（観戦）
  join(token, name) {
    const existing = this.seatOf(token);
    if (existing >= 0) {
      this.seats[existing].name = name;
      return existing;
    }
    const free = this.seats.findIndex((s) => !s);
    if (free < 0) return -1;
    this.seats[free] = { token, name, stack: this.startingStack };
    // ホスト（通常は作成者）が着席していなければ、この人がホストになる
    if (this.seatOf(this.hostToken) < 0) this.hostToken = token;
    return free;
  }

  leave(token) {
    const i = this.seatOf(token);
    if (i < 0) return false;
    this.seats[i] = null;
    if (this.hostToken === token) {
      const next = this.seats.find(Boolean);
      this.hostToken = next ? next.token : null;
    }
    if (this.playerCount < 2 && this.phase !== 'WAITING') {
      this.phase = 'WAITING';
    }
    return true;
  }

  // 次に埋まっている席（時計回り = 席番号の昇順）
  nextOccupied(from) {
    for (let k = 1; k <= this.maxSeats; k++) {
      const i = (from + k) % this.maxSeats;
      if (this.seats[i]) return i;
    }
    return null;
  }

  blindSeats() {
    if (this.buttonSeat == null || this.phase === 'WAITING' || this.playerCount < 2) {
      return { sbSeat: null, bbSeat: null };
    }
    let sbSeat;
    if (this.playerCount === 2 && this.seats[this.buttonSeat]) {
      sbSeat = this.buttonSeat; // ヘッズアップはボタンがSB
    } else {
      sbSeat = this.nextOccupied(this.buttonSeat);
    }
    return { sbSeat, bbSeat: this.nextOccupied(sbSeat) };
  }

  startNewHand() {
    const occupied = this.seats.map((s, i) => (s ? i : -1)).filter((i) => i >= 0);
    this.buttonSeat =
      this.buttonSeat == null
        ? occupied[Math.floor(Math.random() * occupied.length)]
        : this.nextOccupied(this.buttonSeat);
    this.handNumber++;
    this.pot = 0;
    this.phase = 'PREFLOP';
  }

  // ---- ホスト操作（エラー時はメッセージを返す） ----

  start(token) {
    if (!this.isHost(token)) return 'ホストのみ開始できます';
    if (this.phase !== 'WAITING') return 'すでに進行中です';
    if (this.playerCount < 2) return '2人以上必要です';
    if (!this.started) {
      this.started = true;
      if (this.timerEnabled) this.levelEndsAt = Date.now() + this.intervalMs;
    }
    this.startNewHand();
    return null;
  }

  // スタブ: フェーズを1つ進める（SHOWDOWN の次は新しいハンド）
  nextPhase(token) {
    if (!this.isHost(token)) return 'ホストのみ操作できます';
    if (this.phase === 'WAITING') return 'まだ開始していません';
    if (this.playerCount < 2) return '2人以上必要です';
    const i = HAND_PHASES.indexOf(this.phase);
    if (i === HAND_PHASES.length - 1) this.startNewHand();
    else this.phase = HAND_PHASES[i + 1];
    return null;
  }

  togglePause(token) {
    if (!this.isHost(token)) return 'ホストのみ操作できます';
    if (!this.started) return 'まだ開始していません';
    const now = Date.now();
    if (this.paused) {
      this.paused = false;
      if (this.timerEnabled) this.levelEndsAt = now + this.levelRemainingMs;
    } else {
      this.paused = true;
      if (this.timerEnabled) {
        this.levelRemainingMs = Math.max(0, this.levelEndsAt - now);
        this.levelEndsAt = null;
      }
    }
    return null;
  }

  // ブラインドタイマー。レベルが上がったら true
  tick(now) {
    let changed = false;
    while (this.levelEndsAt != null && now >= this.levelEndsAt) {
      this.level++;
      this.levelEndsAt += this.intervalMs;
      changed = true;
    }
    return changed;
  }

  summary() {
    const { sb, bb } = this.blinds;
    return {
      id: this.id,
      name: this.name,
      playerCount: this.playerCount,
      maxSeats: this.maxSeats,
      startingStack: this.startingStack,
      smallBlind: sb,
      bigBlind: bb,
      level: this.level,
      phase: this.phase,
      paused: this.paused,
      timerEnabled: this.timerEnabled,
      intervalMin: this.intervalMin,
      createdAt: this.createdAt,
    };
  }

  // token = 閲覧者のトークン（他人のトークンは送らない）
  publicState(token, connectedTokens) {
    const { sb, bb } = this.blinds;
    const next = Blinds.blindsAt(this.baseSmallBlind, this.baseBigBlind, this.level + 1);
    const host = this.seatOf(this.hostToken);
    return {
      id: this.id,
      name: this.name,
      startingStack: this.startingStack,
      maxSeats: this.maxSeats,
      level: this.level,
      smallBlind: sb,
      bigBlind: bb,
      nextBlinds: { smallBlind: next.sb, bigBlind: next.bb },
      timer: {
        enabled: this.timerEnabled,
        intervalMin: this.intervalMin,
        endsAt: this.levelEndsAt,
        remainingMs: this.levelEndsAt != null ? this.levelEndsAt - Date.now() : this.levelRemainingMs,
        running: this.levelEndsAt != null,
      },
      phase: this.phase,
      started: this.started,
      paused: this.paused,
      pot: this.pot,
      handNumber: this.handNumber,
      buttonSeat: this.phase === 'WAITING' ? null : this.buttonSeat,
      ...this.blindSeats(),
      hostSeat: host >= 0 ? host : null,
      seats: this.seats.map((s, i) =>
        s ? { seat: i, name: s.name, stack: s.stack, connected: connectedTokens.has(s.token) } : null
      ),
      mySeat: this.seatOf(token),
      isHost: this.isHost(token),
      serverNow: Date.now(),
    };
  }
}

class TableManager {
  constructor() {
    this.tables = new Map();
  }

  get(id) {
    return this.tables.get(id);
  }

  list() {
    return [...this.tables.values()]
      .sort((a, b) => b.createdAt - a.createdAt)
      .map((t) => t.summary());
  }

  nameTaken(name) {
    const n = name.toLowerCase();
    return [...this.tables.values()].some((t) => t.name.toLowerCase() === n);
  }

  suggestName() {
    for (;;) {
      const name = `Table #${1000 + crypto.randomInt(9000)}`;
      if (!this.nameTaken(name)) return name;
    }
  }

  create(opts) {
    let id;
    do id = crypto.randomBytes(4).toString('hex');
    while (this.tables.has(id));
    const table = new Table({ ...opts, id });
    this.tables.set(id, table);
    return table;
  }

  delete(id) {
    this.tables.delete(id);
  }
}

module.exports = { TableManager };