/**
 * ComplianceManager.js
 * Manages underage protection, probability disclosure, and anti-cheat measures.
 * Ensures compliance with Chinese gaming regulations and WeChat platform rules.
 */

class ComplianceManager {
  constructor() {
    this._isMinor = false;
    this._monthlySpending = 0;
    this._dailyAdCount = 0;
    this._trackingDate = '';

    this._load();
    this._checkMinorStatus();
  }

  // ============================================================
  // Persistence
  // ============================================================

  /** @private */
  _getTodayKey() {
    const d = new Date();
    return `${d.getFullYear()}-${String(d.getMonth() + 1).padStart(2, '0')}-${String(d.getDate()).padStart(2, '0')}`;
  }

  /** @private */
  _getMonthKey() {
    const d = new Date();
    return `${d.getFullYear()}-${String(d.getMonth() + 1).padStart(2, '0')}`;
  }

  /** @private */
  _load() {
    try {
      if (GameGlobal && GameGlobal.storageManager) {
        const data = GameGlobal.storageManager.get('compliance', null);
        if (data) {
          this._isMinor = data.isMinor || false;

          // Monthly spending
          const currentMonth = this._getMonthKey();
          if (data.spendingMonth === currentMonth) {
            this._monthlySpending = data.monthlySpending || 0;
          }

          // Daily ad count
          const today = this._getTodayKey();
          if (data.adDate === today) {
            this._dailyAdCount = data.dailyAdCount || 0;
          }
          this._trackingDate = today;
        }
      }
    } catch (e) {
      console.warn('[ComplianceManager] Failed to load:', e);
    }
  }

  /** @private */
  _save() {
    try {
      if (GameGlobal && GameGlobal.storageManager) {
        GameGlobal.storageManager.set('compliance', {
          isMinor: this._isMinor,
          spendingMonth: this._getMonthKey(),
          monthlySpending: this._monthlySpending,
          adDate: this._getTodayKey(),
          dailyAdCount: this._dailyAdCount,
        });
      }
    } catch (e) {}
  }

  // ============================================================
  // Minor Status Detection
  // ============================================================

  /**
   * Check if the user is a minor via WeChat platform API.
   * @private
   */
  _checkMinorStatus() {
    // WeChat provides user age info through specific APIs
    // In production, this would call wx.getUserInfo or a server-side check
    // For now, default to non-minor
    try {
      if (typeof wx !== 'undefined' && typeof wx.getSetting === 'function') {
        // Placeholder: in production, check real-name verification status
        console.log('[ComplianceManager] Minor status check: defaulting to adult');
      }
    } catch (e) {}
  }

  // ============================================================
  // Public API
  // ============================================================

  /**
   * Whether the current user is identified as a minor.
   * @returns {boolean}
   */
  isMinor() {
    return this._isMinor;
  }

  /**
   * Set minor status (called after real-name verification).
   * @param {boolean} isMinor
   */
  setMinorStatus(isMinor) {
    this._isMinor = isMinor;
    this._save();
  }

  /**
   * Check if a purchase is allowed for the current user.
   * Minors: monthly limit ¥400, single purchase > ¥50 requires confirmation.
   * @param {number} amountFen - Purchase amount in fen (分).
   * @returns {{ allowed: boolean, needsConfirmation: boolean, reason?: string }}
   */
  checkPurchaseRestriction(amountFen) {
    if (!this._isMinor) {
      return { allowed: true, needsConfirmation: false };
    }

    const amountYuan = amountFen / 100;

    // Monthly limit: ¥400
    const newTotal = this._monthlySpending + amountFen;
    if (newTotal > 40000) { // 400 yuan in fen
      return {
        allowed: false,
        needsConfirmation: false,
        reason: 'monthly_limit',
      };
    }

    // Single purchase > ¥50 needs confirmation
    if (amountYuan > 50) {
      return {
        allowed: true,
        needsConfirmation: true,
        reason: 'large_purchase',
      };
    }

    return { allowed: true, needsConfirmation: false };
  }

  /**
   * Record a successful purchase amount.
   * @param {number} amountFen
   */
  recordPurchase(amountFen) {
    this._monthlySpending += amountFen;
    this._save();
  }

  /**
   * Check if an ad can be shown to the current user.
   * Minors: max 5 ads per day.
   * @returns {boolean}
   */
  canShowAd() {
    if (!this._isMinor) return true;

    const today = this._getTodayKey();
    if (this._trackingDate !== today) {
      this._trackingDate = today;
      this._dailyAdCount = 0;
    }

    return this._dailyAdCount < 5;
  }

  /**
   * Record an ad shown to the user.
   */
  recordAdShown() {
    if (!this._isMinor) return;

    const today = this._getTodayKey();
    if (this._trackingDate !== today) {
      this._trackingDate = today;
      this._dailyAdCount = 0;
    }

    this._dailyAdCount++;
    this._save();
  }

  /**
   * Validate game session data for anti-cheat.
   * Checks for impossible stats (e.g., too many kills in too short time).
   * @param {object} stats - { kills, timeElapsed, score }
   * @returns {{ valid: boolean, flags: string[] }}
   */
  validateGameSession(stats) {
    const flags = [];

    if (!stats) return { valid: true, flags };

    // Check impossible kill rate (>10 kills per minute)
    if (stats.kills && stats.timeElapsed) {
      const killsPerMinute = stats.kills / (stats.timeElapsed / 60);
      if (killsPerMinute > 10) {
        flags.push('suspicious_kill_rate');
      }
    }

    // Check impossible score
    if (stats.score && stats.score > 100000) {
      flags.push('suspicious_score');
    }

    // Check suspicious ad reward frequency
    // (anti-cheat for ad reward manipulation)
    return {
      valid: flags.length === 0,
      flags,
    };
  }
}

module.exports = ComplianceManager;