// Copyright 2014 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
/**
 * @unrestricted
 */
export default class ShortcutRegistry {
  /**
   * @param {!UI.ActionRegistry} actionRegistry
   * @param {!Document} document
   */
  constructor(actionRegistry, document) {
    this._actionRegistry = actionRegistry;
    /** @type {!Platform.Multimap.<string, string>} */
    this._defaultKeyToActions = new Platform.Multimap();
    /** @type {!Platform.Multimap.<string, !UI.KeyboardShortcut.Descriptor>} */
    this._defaultActionToShortcut = new Platform.Multimap();
    this._registerBindings(document);
  }

  /**
   * @param {number} key
   * @return {!Array.<!UI.Action>}
   */
  _applicableActions(key) {
    return this._actionRegistry.applicableActions(this._defaultActionsForKey(key).valuesArray(), UI.context);
  }

  /**
   * @param {number} key
   * @return {!Set.<string>}
   */
  _defaultActionsForKey(key) {
    return this._defaultKeyToActions.get(String(key));
  }

  /**
   * @return {!Array<number>}
   */
  globalShortcutKeys() {
    const keys = [];
    for (const key of this._defaultKeyToActions.keysArray()) {
      const actions = this._defaultKeyToActions.get(key).valuesArray();
      const applicableActions = this._actionRegistry.applicableActions(actions, new UI.Context());
      if (applicableActions.length) {
        keys.push(Number(key));
      }
    }
    return keys;
  }

  /**
   * @param {string} actionId
   * @return {!Array.<!UI.KeyboardShortcut.Descriptor>}
   */
  shortcutDescriptorsForAction(actionId) {
    return this._defaultActionToShortcut.get(actionId).valuesArray();
  }

  /**
   * @param {!Array.<string>} actionIds
   * @return {!Array.<number>}
   */
  keysForActions(actionIds) {
    const result = [];
    for (let i = 0; i < actionIds.length; ++i) {
      const descriptors = this.shortcutDescriptorsForAction(actionIds[i]);
      for (let j = 0; j < descriptors.length; ++j) {
        result.push(descriptors[j].key);
      }
    }
    return result;
  }

  /**
   * @param {string} actionId
   * @return {string|undefined}
   */
  shortcutTitleForAction(actionId) {
    const descriptors = this.shortcutDescriptorsForAction(actionId);
    if (descriptors.length) {
      return descriptors[0].name;
    }
  }

  /**
   * @param {!KeyboardEvent} event
   */
  handleShortcut(event) {
    this.handleKey(UI.KeyboardShortcut.makeKeyFromEvent(event), event.key, event);
  }

  /**
   * @param {!KeyboardEvent} event
   * @param {string} actionId
   * @return {boolean}
   */
  eventMatchesAction(event, actionId) {
    console.assert(this._defaultActionToShortcut.has(actionId), 'Unknown action ' + actionId);
    const key = UI.KeyboardShortcut.makeKeyFromEvent(event);
    return this._defaultActionToShortcut.get(actionId).valuesArray().some(descriptor => descriptor.key === key);
  }

  /**
   * @param {!Element} element
   * @param {string} actionId
   * @param {function():boolean} listener
   * @param {boolean=} capture
   */
  addShortcutListener(element, actionId, listener, capture) {
    console.assert(this._defaultActionToShortcut.has(actionId), 'Unknown action ' + actionId);
    element.addEventListener('keydown', event => {
      if (!this.eventMatchesAction(/** @type {!KeyboardEvent} */ (event), actionId) || !listener.call(null)) {
        return;
      }
      event.consume(true);
    }, capture);
  }

  /**
   * @param {number} key
   * @param {string} domKey
   * @param {!KeyboardEvent=} event
   */
  async handleKey(key, domKey, event) {
    const keyModifiers = key >> 8;
    const actions = this._applicableActions(key);
    if (!actions.length || isPossiblyInputKey()) {
      return;
    }
    if (event) {
      event.consume(true);
    }
    if (UI.Dialog.hasInstance()) {
      return;
    }
    for (const action of actions) {
      try {
        const result = await action.execute();
        if (result) {
          return;
        }
      } catch (e) {
        console.error(e);
        throw e;
      }
    }

    /**
     * @return {boolean}
     */
    function isPossiblyInputKey() {
      if (!event || !UI.isEditing() || /^F\d+|Control|Shift|Alt|Meta|Escape|Win|U\+001B$/.test(domKey)) {
        return false;
      }

      if (!keyModifiers) {
        return true;
      }

      const modifiers = UI.KeyboardShortcut.Modifiers;
      // Undo/Redo will also cause input, so textual undo should take precedence over DevTools undo when editing.
      if (Host.isMac()) {
        if (UI.KeyboardShortcut.makeKey('z', modifiers.Meta) === key) {
          return true;
        }
        if (UI.KeyboardShortcut.makeKey('z', modifiers.Meta | modifiers.Shift) === key) {
          return true;
        }
      } else {
        if (UI.KeyboardShortcut.makeKey('z', modifiers.Ctrl) === key) {
          return true;
        }
        if (UI.KeyboardShortcut.makeKey('y', modifiers.Ctrl) === key) {
          return true;
        }
        if (!Host.isWin() && UI.KeyboardShortcut.makeKey('z', modifiers.Ctrl | modifiers.Shift) === key) {
          return true;
        }
      }

      if ((keyModifiers & (modifiers.Ctrl | modifiers.Alt)) === (modifiers.Ctrl | modifiers.Alt)) {
        return Host.isWin();
      }

      return !hasModifier(modifiers.Ctrl) && !hasModifier(modifiers.Alt) && !hasModifier(modifiers.Meta);
    }

    /**
     * @param {number} mod
     * @return {boolean}
     */
    function hasModifier(mod) {
      return !!(keyModifiers & mod);
    }
  }

  /**
   * @param {string} actionId
   * @param {string} shortcut
   */
  registerShortcut(actionId, shortcut) {
    const descriptor = UI.KeyboardShortcut.makeDescriptorFromBindingShortcut(shortcut);
    if (!descriptor) {
      return;
    }
    this._defaultActionToShortcut.set(actionId, descriptor);
    this._defaultKeyToActions.set(String(descriptor.key), actionId);
  }

  /**
   * @param {!Document} document
   */
  _registerBindings(document) {
    const extensions = self.runtime.extensions('action');
    extensions.forEach(registerExtension, this);

    /**
     * @param {!Root.Runtime.Extension} extension
     * @this {ShortcutRegistry}
     */
    function registerExtension(extension) {
      const descriptor = extension.descriptor();
      const bindings = descriptor['bindings'];
      for (let i = 0; bindings && i < bindings.length; ++i) {
        if (!platformMatches(bindings[i].platform)) {
          continue;
        }
        const shortcuts = bindings[i]['shortcut'].split(/\s+/);
        shortcuts.forEach(this.registerShortcut.bind(this, descriptor['actionId']));
      }
    }

    /**
     * @param {string=} platformsString
     * @return {boolean}
     */
    function platformMatches(platformsString) {
      if (!platformsString) {
        return true;
      }
      const platforms = platformsString.split(',');
      let isMatch = false;
      const currentPlatform = Host.platform();
      for (let i = 0; !isMatch && i < platforms.length; ++i) {
        isMatch = platforms[i] === currentPlatform;
      }
      return isMatch;
    }
  }
}

/**
 * @unrestricted
 */
export class ForwardedShortcut {}

ForwardedShortcut.instance = new ForwardedShortcut();

/** @type {!ShortcutRegistry} */
UI.shortcutRegistry;

/* Legacy exported object*/
self.UI = self.UI || {};

/* Legacy exported object*/
UI = UI || {};

/** @constructor */
UI.ShortcutRegistry = ShortcutRegistry;

/**
 * @unrestricted
 */
UI.ShortcutRegistry.ForwardedShortcut = ForwardedShortcut;