/**
 * MetonaToast Plugins - 插件系统
 * @module plugins
 * @version 2.0.0
 * @description 插件管理器 + 3 款预设插件 (keyboard / persistence / accessibility)
 */

import { t } from './i18n.js';

/**
 * 插件管理器
 */
class PluginManager {
  constructor() {
    this.plugins = new Map();
    this.initialized = false;
  }

  register(name, plugin) {
    if (this.plugins.has(name)) {
      console.warn(`Plugin "${name}" is already registered`);
      return this;
    }
    if (!plugin || typeof plugin !== 'object' || (!plugin.name && !plugin.version)) {
      console.error(`Invalid plugin "${name}"`);
      return this;
    }

    this.plugins.set(name, { name, ...plugin, installed: false, enabled: true });

    if (plugin.install) {
      try { plugin.install(this); this.plugins.get(name).installed = true; }
      catch (e) { console.error(`Failed to install plugin "${name}":`, e); }
    }
    return this;
  }

  unregister(name) {
    const plugin = this.plugins.get(name);
    if (!plugin) return this;
    if (plugin.uninstall) {
      try { plugin.uninstall(this); } catch (e) { console.error(`Failed to uninstall plugin "${name}":`, e); }
    }
    this.plugins.delete(name);
    return this;
  }

  get(name)     { return this.plugins.get(name) || null; }
  has(name)     { return this.plugins.has(name); }
  getAll()      { return Array.from(this.plugins.values()); }
  getNames()    { return Array.from(this.plugins.keys()); }

  enable(name) {
    const p = this.plugins.get(name);
    if (p) p.enabled = true;
    return this;
  }
  disable(name) {
    const p = this.plugins.get(name);
    if (p) p.enabled = false;
    return this;
  }
  isEnabled(name) {
    const p = this.plugins.get(name);
    return p ? p.enabled : false;
  }

  destroy() {
    this.plugins.forEach((p, name) => {
      if (p.destroy) { try { p.destroy(this); } catch (e) {} }
    });
    this.plugins.clear();
  }
}

/**
 * 预设插件
 */
const presetPlugins = {

  /**
   * 键盘快捷键插件 — ESC 关闭所有 Toast
   */
  keyboard: {
    name: 'keyboard',
    version: '1.0.0',
    description: 'ESC 关闭所有 Toast',

    _handler: null,

    install() {
      if (typeof document === 'undefined') return;
      this._handler = (e) => {
        if (e.key === 'Escape') {
          // 点击所有关闭按钮
          document.querySelectorAll('.met-toast .met-close').forEach(btn => {
            try { btn.click(); } catch (_) {}
          });
        }
      };
      document.addEventListener('keydown', this._handler);
    },

    uninstall() {
      if (this._handler && typeof document !== 'undefined') {
        document.removeEventListener('keydown', this._handler);
        this._handler = null;
      }
    },
  },

  /**
   * 持久化插件 — 自动保存/加载配置到 localStorage
   */
  persistence: {
    name: 'persistence',
    version: '1.0.0',
    description: '自动持久化配置到 localStorage',
    storageKey: 'metona-toast-config',

    install() {
      // 加载已保存的配置
      if (typeof localStorage !== 'undefined') {
        try {
          const saved = localStorage.getItem(this.storageKey);
          return saved ? JSON.parse(saved) : null;
        } catch (_) { return null; }
      }
      return null;
    },

    save(config) {
      if (typeof localStorage !== 'undefined') {
        try { localStorage.setItem(this.storageKey, JSON.stringify(config)); } catch (_) {}
      }
    },

    uninstall() {
      if (typeof localStorage !== 'undefined') {
        try { localStorage.removeItem(this.storageKey); } catch (_) {}
      }
    },
  },

  /**
   * 无障碍插件 — 屏幕阅读器公告
   */
  accessibility: {
    name: 'accessibility',
    version: '1.0.0',
    description: '通过屏幕阅读器朗读 Toast 内容',

    announce(toast) {
      if (typeof document === 'undefined') return;
      const el = document.createElement('div');
      el.setAttribute('aria-live', 'assertive');
      el.setAttribute('aria-atomic', 'true');
      el.style.cssText = 'position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0;';
      const typeName = t(toast.type) || toast.type;
      el.textContent = `${typeName}: ${toast.title || ''} ${toast.message || ''}`;
      document.body.appendChild(el);
      setTimeout(() => { if (el.parentNode) el.parentNode.removeChild(el); }, 3000);
    },
  },
};

/**
 * 插件工具
 */
const pluginUtils = {
  createManager() { return new PluginManager(); },
  register(name, plugin) { return defaultPluginManager.register(name, plugin); },
  unregister(name)        { return defaultPluginManager.unregister(name); },
  get(name)               { return defaultPluginManager.get(name); },
  has(name)               { return defaultPluginManager.has(name); },
  getAll()                { return defaultPluginManager.getAll(); },
  getNames()              { return defaultPluginManager.getNames(); },
  enable(name)            { return defaultPluginManager.enable(name); },
  disable(name)           { return defaultPluginManager.disable(name); },
  isEnabled(name)         { return defaultPluginManager.isEnabled(name); },
  getPreset(name)         { return presetPlugins[name] || null; },
  getAllPresets()         { return { ...presetPlugins }; },

  createPlugin(config) {
    return {
      name: config.name || 'custom',
      version: config.version || '1.0.0',
      description: config.description || '',
      hooks: config.hooks || {},
      install: config.install || null,
      uninstall: config.uninstall || null,
      ...config,
    };
  },

  validatePlugin(plugin) {
    const errors = [];
    if (!plugin || typeof plugin !== 'object') errors.push('Plugin must be an object');
    if (!plugin.name && !plugin.version) errors.push('Plugin must have a name or version');
    return { valid: errors.length === 0, errors };
  },
};

const defaultPluginManager = new PluginManager();

export { presetPlugins, pluginUtils, defaultPluginManager, PluginManager };