/**
 * SkinManager.js
 * Manages tank skin purchases, equipping, and persistence.
 * Skins are cosmetic-only color schemes purchased with gold.
 */

/** Skin definitions with id, name, cost, and color scheme. */
const SKINS = {
  default: {
    id: 'default',
    nameKey: 'skin.default',
    cost: 0,
    colors: null, // uses default tank color
    preview: '#FFD700',
  },
  arctic: {
    id: 'arctic',
    nameKey: 'skin.arctic',
    cost: 500,
    colors: { body: '#B0E0E6', turret: '#5F9EA0', track: '#2F4F4F' },
    preview: '#B0E0E6',
  },
  inferno: {
    id: 'inferno',
    nameKey: 'skin.inferno',
    cost: 800,
    colors: { body: '#FF4500', turret: '#8B0000', track: '#2F0000' },
    preview: '#FF4500',
  },
  phantom: {
    id: 'phantom',
    nameKey: 'skin.phantom',
    cost: 1200,
    colors: { body: '#9370DB', turret: '#4B0082', track: '#1C0033' },
    preview: '#9370DB',
  },
  jungle: {
    id: 'jungle',
    nameKey: 'skin.jungle',
    cost: 1000,
    colors: { body: '#3CB371', turret: '#006400', track: '#002200' },
    preview: '#3CB371',
  },
  neon: {
    id: 'neon',
    nameKey: 'skin.neon',
    cost: 2000,
    colors: { body: '#00FF7F', turret: '#00CED1', track: '#008B8B' },
    preview: '#00FF7F',
  },
  shadow: {
    id: 'shadow',
    nameKey: 'skin.shadow',
    cost: 3000,
    colors: { body: '#2C2C2C', turret: '#1A1A1A', track: '#0D0D0D' },
    preview: '#2C2C2C',
  },
  royal: {
    id: 'royal',
    nameKey: 'skin.royal',
    cost: 5000,
    colors: { body: '#FFD700', turret: '#DAA520', track: '#B8860B' },
    preview: '#FFD700',
  },
};

/** Ordered list of skin IDs for display. */
const SKIN_ORDER = ['default', 'arctic', 'inferno', 'jungle', 'phantom', 'neon', 'shadow', 'royal'];

class SkinManager {
  constructor() {
    /** @type {Set<string>} Unlocked skin IDs. */
    this._unlocked = new Set(['default']);

    /** @type {string} Currently equipped skin ID. */
    this._equipped = 'default';

    this._load();
  }

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

  /** @private */
  _load() {
    try {
      if (GameGlobal && GameGlobal.storageManager) {
        const data = GameGlobal.storageManager.get('skins', null);
        if (data) {
          this._unlocked = new Set(data.unlocked || ['default']);
          this._equipped = data.equipped || 'default';
          // Ensure default is always unlocked
          this._unlocked.add('default');
        }
      }
    } catch (e) {
      console.warn('[SkinManager] Failed to load skin data:', e);
    }
  }

  /** @private */
  _save() {
    try {
      if (GameGlobal && GameGlobal.storageManager) {
        GameGlobal.storageManager.set('skins', {
          unlocked: Array.from(this._unlocked),
          equipped: this._equipped,
        });
      }
    } catch (e) {
      console.warn('[SkinManager] Failed to save skin data:', e);
    }
  }

  // ============================================================
  // Queries
  // ============================================================

  /**
   * Get all skin definitions in display order.
   * @returns {Array<object>}
   */
  getAllSkins() {
    return SKIN_ORDER.map(id => SKINS[id]);
  }

  /**
   * Check if a skin is unlocked.
   * @param {string} skinId
   * @returns {boolean}
   */
  isUnlocked(skinId) {
    return this._unlocked.has(skinId);
  }

  /**
   * Get the currently equipped skin ID.
   * @returns {string}
   */
  getEquippedSkinId() {
    return this._equipped;
  }

  /**
   * Get the color scheme for the currently equipped skin.
   * @returns {object|null} { body, turret, track } or null for default.
   */
  getCurrentSkinColors() {
    const skin = SKINS[this._equipped];
    if (!skin) return null;
    return skin.colors; // null for default skin
  }

  /**
   * Get skin definition by ID.
   * @param {string} skinId
   * @returns {object|null}
   */
  getSkin(skinId) {
    return SKINS[skinId] || null;
  }

  // ============================================================
  // Actions
  // ============================================================

  /**
   * Purchase a skin with gold.
   * @param {string} skinId
   * @returns {{ success: boolean, error?: string }}
   */
  purchaseSkin(skinId) {
    const skin = SKINS[skinId];
    if (!skin) {
      return { success: false, error: 'Invalid skin' };
    }

    if (this._unlocked.has(skinId)) {
      return { success: false, error: 'Already unlocked' };
    }

    const cm = GameGlobal.currencyManager;
    if (!cm || !cm.hasGold(skin.cost)) {
      return { success: false, error: 'Insufficient gold' };
    }

    const spent = cm.spendGold(skin.cost);
    if (!spent) {
      return { success: false, error: 'Insufficient gold' };
    }

    this._unlocked.add(skinId);
    this._save();

    console.log(`[SkinManager] Purchased skin: ${skinId} for ${skin.cost} gold`);

    // Emit event
    try {
      if (GameGlobal.eventBus) {
        GameGlobal.eventBus.emit('skin:purchased', { id: skinId, cost: skin.cost });
      }
    } catch (e) {}

    return { success: true };
  }

  /**
   * Equip an unlocked skin.
   * @param {string} skinId
   * @returns {{ success: boolean, error?: string }}
   */
  equipSkin(skinId) {
    if (!SKINS[skinId]) {
      return { success: false, error: 'Invalid skin' };
    }

    if (!this._unlocked.has(skinId)) {
      return { success: false, error: 'Not unlocked' };
    }

    this._equipped = skinId;
    this._save();

    console.log(`[SkinManager] Equipped skin: ${skinId}`);

    // Emit event
    try {
      if (GameGlobal.eventBus) {
        GameGlobal.eventBus.emit('skin:equipped', { id: skinId });
      }
    } catch (e) {}

    return { success: true };
  }

  // ============================================================
  // Cloud Sync
  // ============================================================

  /**
   * Get skin data for cloud sync.
   * @returns {object}
   */
  getCloudSyncData() {
    return {
      unlocked: Array.from(this._unlocked),
      equipped: this._equipped,
    };
  }

  /**
   * Restore skin data from cloud (merge: keep all unlocked).
   * @param {object} cloudData
   */
  restoreFromCloud(cloudData) {
    if (!cloudData) return;

    if (cloudData.unlocked) {
      for (const id of cloudData.unlocked) {
        if (SKINS[id]) {
          this._unlocked.add(id);
        }
      }
    }

    if (cloudData.equipped && SKINS[cloudData.equipped] && this._unlocked.has(cloudData.equipped)) {
      this._equipped = cloudData.equipped;
    }

    this._save();
  }
}

module.exports = SkinManager;