// Copyright 2016 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.

/* eslint-disable rulesdir/no_underscored_properties */

import * as Common from '../common/common.js';
import * as Host from '../host/host.js';
import * as i18n from '../i18n/i18n.js';
import * as ObjectUI from '../object_ui/object_ui.js';
import * as Root from '../root/root.js';
import * as SDK from '../sdk/sdk.js';
import * as TextUtils from '../text_utils/text_utils.js';
import * as UI from '../ui/ui.js';

import {ConsolePanel} from './ConsolePanel.js';

export const UIStrings = {
  /**
  *@description Text in Console Prompt of the Console panel
  */
  consolePrompt: 'Console prompt',
};
const str_ = i18n.i18n.registerUIStrings('console/ConsolePrompt.ts', UIStrings);
const i18nString = i18n.i18n.getLocalizedString.bind(undefined, str_);
export class ConsolePrompt extends UI.Widget.Widget {
  _addCompletionsFromHistory: boolean;
  _history: ConsoleHistoryManager;
  _initialText: string;
  _editor: UI.TextEditor.TextEditor|null;
  _eagerPreviewElement: HTMLDivElement;
  _textChangeThrottler: Common.Throttler.Throttler;
  _formatter: ObjectUI.RemoteObjectPreviewFormatter.RemoteObjectPreviewFormatter;
  _requestPreviewBound: () => Promise<void>;
  _innerPreviewElement: HTMLElement;
  _promptIcon: UI.Icon.Icon;
  _iconThrottler: Common.Throttler.Throttler;
  _eagerEvalSetting: Common.Settings.Setting<boolean>;
  _previewRequestForTest: Promise<void>|null;
  _defaultAutocompleteConfig: UI.TextEditor.AutocompleteConfig|null;
  _highlightingNode: boolean;

  constructor() {
    super();
    this.registerRequiredCSS('console/consolePrompt.css', {enableLegacyPatching: false});
    this._addCompletionsFromHistory = true;
    this._history = new ConsoleHistoryManager();

    this._initialText = '';
    this._editor = null;
    this._eagerPreviewElement = document.createElement('div');
    this._eagerPreviewElement.classList.add('console-eager-preview');
    this._textChangeThrottler = new Common.Throttler.Throttler(150);
    this._formatter = new ObjectUI.RemoteObjectPreviewFormatter.RemoteObjectPreviewFormatter();
    this._requestPreviewBound = this._requestPreview.bind(this);
    this._innerPreviewElement = this._eagerPreviewElement.createChild('div', 'console-eager-inner-preview');
    this._eagerPreviewElement.appendChild(UI.Icon.Icon.create('smallicon-command-result', 'preview-result-icon'));

    const editorContainerElement = this.element.createChild('div', 'console-prompt-editor-container');
    this.element.appendChild(this._eagerPreviewElement);

    this._promptIcon = UI.Icon.Icon.create('smallicon-text-prompt', 'console-prompt-icon');
    this.element.appendChild(this._promptIcon);
    this._iconThrottler = new Common.Throttler.Throttler(0);

    this._eagerEvalSetting = Common.Settings.Settings.instance().moduleSetting('consoleEagerEval');
    this._eagerEvalSetting.addChangeListener(this._eagerSettingChanged.bind(this));
    this._eagerPreviewElement.classList.toggle('hidden', !this._eagerEvalSetting.get());

    this.element.tabIndex = 0;
    this._previewRequestForTest = null;

    this._defaultAutocompleteConfig = null;

    this._highlightingNode = false;

    const extension =
        (Root.Runtime.Runtime.instance().extension(UI.TextEditor.TextEditorFactory) as Root.Runtime.Extension);
    extension.instance().then(factory => {
      gotFactory.call(this, (factory as UI.TextEditor.TextEditorFactory));
    });

    function gotFactory(this: ConsolePrompt, factory: UI.TextEditor.TextEditorFactory): void {
      const options = {
        devtoolsAccessibleName: (i18nString(UIStrings.consolePrompt) as string),
        lineNumbers: false,
        lineWrapping: true,
        mimeType: 'javascript',
        autoHeight: true,
      };
      this._editor = factory.createEditor((options as UI.TextEditor.Options));

      this._defaultAutocompleteConfig =
          ObjectUI.JavaScriptAutocomplete.JavaScriptAutocompleteConfig.createConfigForEditor(this._editor);
      this._editor.configureAutocomplete(Object.assign({}, this._defaultAutocompleteConfig, {
        suggestionsCallback: this._wordsWithQuery.bind(this),
        anchorBehavior: UI.GlassPane.AnchorBehavior.PreferTop,
      }));
      this._editor.widget().element.addEventListener('keydown', this._editorKeyDown.bind(this), true);
      this._editor.widget().show(editorContainerElement);
      this._editor.addEventListener(UI.TextEditor.Events.CursorChanged, this._updatePromptIcon, this);
      this._editor.addEventListener(UI.TextEditor.Events.TextChanged, this._onTextChanged, this);
      this._editor.addEventListener(UI.TextEditor.Events.SuggestionChanged, this._onTextChanged, this);

      this.setText(this._initialText);
      this._initialText = '';
      if (this.hasFocus()) {
        this.focus();
      }
      this.element.removeAttribute('tabindex');
      this._editor.widget().element.tabIndex = -1;

      this._editorSetForTest();

      // Record the console tool load time after the console prompt constructor is complete.
      Host.userMetrics.panelLoaded('console', 'DevTools.Launch.Console');
    }
  }

  _eagerSettingChanged(): void {
    const enabled = this._eagerEvalSetting.get();
    this._eagerPreviewElement.classList.toggle('hidden', !enabled);
    if (enabled) {
      this._requestPreview();
    }
  }

  belowEditorElement(): Element {
    return this._eagerPreviewElement;
  }

  _onTextChanged(): void {
    // ConsoleView and prompt both use a throttler, so we clear the preview
    // ASAP to avoid inconsistency between a fresh viewport and stale preview.
    if (this._eagerEvalSetting.get()) {
      const asSoonAsPossible = !this._editor || !this._editor.textWithCurrentSuggestion();
      this._previewRequestForTest = this._textChangeThrottler.schedule(this._requestPreviewBound, asSoonAsPossible);
    }
    this._updatePromptIcon();
    this.dispatchEventToListeners(Events.TextChanged);
  }

  async _requestPreview(): Promise<void> {
    if (!this._editor) {
      return;
    }
    const text = this._editor.textWithCurrentSuggestion().trim();
    const executionContext = UI.Context.Context.instance().flavor(SDK.RuntimeModel.ExecutionContext);
    const {preview, result} =
        await ObjectUI.JavaScriptREPL.JavaScriptREPL.evaluateAndBuildPreview(text, true /* throwOnSideEffect */, 500);
    this._innerPreviewElement.removeChildren();
    if (preview.deepTextContent() !== this._editor.textWithCurrentSuggestion().trim()) {
      this._innerPreviewElement.appendChild(preview);
    }
    if (result && 'object' in result && result.object && result.object.subtype === 'node') {
      this._highlightingNode = true;
      SDK.OverlayModel.OverlayModel.highlightObjectAsDOMNode(result.object);
    } else if (this._highlightingNode) {
      this._highlightingNode = false;
      SDK.OverlayModel.OverlayModel.hideDOMNodeHighlight();
    }
    if (result && executionContext) {
      executionContext.runtimeModel.releaseEvaluationResult(result);
    }
  }

  willHide(): void {
    if (this._highlightingNode) {
      this._highlightingNode = false;
      SDK.OverlayModel.OverlayModel.hideDOMNodeHighlight();
    }
  }

  history(): ConsoleHistoryManager {
    return this._history;
  }

  clearAutocomplete(): void {
    if (this._editor) {
      this._editor.clearAutocomplete();
    }
  }

  _isCaretAtEndOfPrompt(): boolean {
    return this._editor !== null &&
        this._editor.selection().collapseToEnd().equal(this._editor.fullRange().collapseToEnd());
  }

  moveCaretToEndOfPrompt(): void {
    if (this._editor) {
      this._editor.setSelection(TextUtils.TextRange.TextRange.createFromLocation(Infinity, Infinity));
    }
  }

  setText(text: string): void {
    if (this._editor) {
      this._editor.setText(text);
    } else {
      this._initialText = text;
    }
    this.dispatchEventToListeners(Events.TextChanged);
  }

  text(): string {
    return this._editor ? this._editor.text() : this._initialText;
  }

  setAddCompletionsFromHistory(value: boolean): void {
    this._addCompletionsFromHistory = value;
  }

  _editorKeyDown(event: Event): void {
    if (!this._editor) {
      return;
    }
    const keyboardEvent = (event as KeyboardEvent);
    let newText;
    let isPrevious;
    // Check against visual coordinates in case lines wrap.
    const selection = this._editor.selection();
    const cursorY = this._editor.visualCoordinates(selection.endLine, selection.endColumn).y;

    switch (keyboardEvent.keyCode) {
      case UI.KeyboardShortcut.Keys.Up.code: {
        const startY = this._editor.visualCoordinates(0, 0).y;
        if (keyboardEvent.shiftKey || !selection.isEmpty() || cursorY !== startY) {
          break;
        }
        newText = this._history.previous(this.text());
        isPrevious = true;
        break;
      }
      case UI.KeyboardShortcut.Keys.Down.code: {
        const fullRange = this._editor.fullRange();
        const endY = this._editor.visualCoordinates(fullRange.endLine, fullRange.endColumn).y;
        if (keyboardEvent.shiftKey || !selection.isEmpty() || cursorY !== endY) {
          break;
        }
        newText = this._history.next();
        break;
      }
      case UI.KeyboardShortcut.Keys.P.code: {  // Ctrl+P = Previous
        if (Host.Platform.isMac() && keyboardEvent.ctrlKey && !keyboardEvent.metaKey && !keyboardEvent.altKey &&
            !keyboardEvent.shiftKey) {
          newText = this._history.previous(this.text());
          isPrevious = true;
        }
        break;
      }
      case UI.KeyboardShortcut.Keys.N.code: {  // Ctrl+N = Next
        if (Host.Platform.isMac() && keyboardEvent.ctrlKey && !keyboardEvent.metaKey && !keyboardEvent.altKey &&
            !keyboardEvent.shiftKey) {
          newText = this._history.next();
        }
        break;
      }
      case UI.KeyboardShortcut.Keys.Enter.code: {
        this._enterKeyPressed(keyboardEvent);
        break;
      }
      case UI.KeyboardShortcut.Keys.Tab.code: {
        if (!this.text()) {
          keyboardEvent.consume();
        }
        break;
      }
    }

    if (newText === undefined) {
      return;
    }
    keyboardEvent.consume(true);
    this.setText(newText);

    if (isPrevious) {
      this._editor.setSelection(TextUtils.TextRange.TextRange.createFromLocation(0, Infinity));
    } else {
      this.moveCaretToEndOfPrompt();
    }
  }

  async _enterWillEvaluate(): Promise<boolean> {
    if (!this._isCaretAtEndOfPrompt()) {
      return true;
    }
    return await ObjectUI.JavaScriptAutocomplete.JavaScriptAutocomplete.isExpressionComplete(this.text());
  }

  _updatePromptIcon(): void {
    this._iconThrottler.schedule(async () => {
      const canComplete = await this._enterWillEvaluate();
      this._promptIcon.classList.toggle('console-prompt-incomplete', !canComplete);
    });
  }

  async _enterKeyPressed(event: KeyboardEvent): Promise<void> {
    if (event.altKey || event.ctrlKey || event.shiftKey) {
      return;
    }

    event.consume(true);

    // Since we prevent default, manually emulate the native "scroll on key input" behavior.
    this.element.scrollIntoView();
    this.clearAutocomplete();

    const str = this.text();
    if (!str.length) {
      return;
    }

    if (await this._enterWillEvaluate()) {
      await this._appendCommand(str, true);
    } else if (this._editor) {
      this._editor.newlineAndIndent();
    }
    this._enterProcessedForTest();
  }

  async _appendCommand(text: string, useCommandLineAPI: boolean): Promise<void> {
    this.setText('');
    const currentExecutionContext = UI.Context.Context.instance().flavor(SDK.RuntimeModel.ExecutionContext);
    if (currentExecutionContext) {
      const executionContext = currentExecutionContext;
      const message = SDK.ConsoleModel.ConsoleModel.instance().addCommandMessage(executionContext, text);
      const expression = ObjectUI.JavaScriptREPL.JavaScriptREPL.preprocessExpression(text);
      SDK.ConsoleModel.ConsoleModel.instance().evaluateCommandInConsole(
          executionContext, message, expression, useCommandLineAPI);
      if (ConsolePanel.instance().isShowing()) {
        Host.userMetrics.actionTaken(Host.UserMetrics.Action.CommandEvaluatedInConsolePanel);
      }
    }
  }

  _enterProcessedForTest(): void {
  }

  _historyCompletions(prefix: string, force?: boolean): UI.SuggestBox.Suggestions {
    const text = this.text();
    if (!this._addCompletionsFromHistory || !this._isCaretAtEndOfPrompt() || (!text && !force)) {
      return [];
    }
    const result = [];
    const set = new Set<string>();
    const data = this._history.historyData();
    for (let i = data.length - 1; i >= 0 && result.length < 50; --i) {
      const item = data[i];
      if (!item.startsWith(text)) {
        continue;
      }
      if (set.has(item)) {
        continue;
      }
      set.add(item);
      result.push(
          {text: item.substring(text.length - prefix.length), iconType: 'smallicon-text-prompt', isSecondary: true});
    }
    return result as UI.SuggestBox.Suggestions;
  }

  focus(): void {
    if (this._editor) {
      this._editor.widget().focus();
    } else {
      this.element.focus();
    }
  }

  async _wordsWithQuery(
      queryRange: TextUtils.TextRange.TextRange, substituteRange: TextUtils.TextRange.TextRange,
      force?: boolean): Promise<UI.SuggestBox.Suggestions> {
    if (!this._editor || !this._defaultAutocompleteConfig || !this._defaultAutocompleteConfig.suggestionsCallback) {
      return [];
    }
    const query = this._editor.text(queryRange);
    const words = await this._defaultAutocompleteConfig.suggestionsCallback(queryRange, substituteRange, force);
    const historyWords = this._historyCompletions(query, force);
    return words ? words.concat(historyWords) : historyWords;
  }

  _editorSetForTest(): void {
  }
}

export class ConsoleHistoryManager {
  _data: string[];
  _historyOffset: number;
  _uncommittedIsTop?: boolean;
  constructor() {
    this._data = [];

    /**
     * 1-based entry in the history stack.
     */
    this._historyOffset = 1;
  }

  historyData(): string[] {
    return this._data;
  }

  setHistoryData(data: string[]): void {
    this._data = data.slice();
    this._historyOffset = 1;
  }

  /**
   * Pushes a committed text into the history.
   */
  pushHistoryItem(text: string): void {
    if (this._uncommittedIsTop) {
      this._data.pop();
      delete this._uncommittedIsTop;
    }

    this._historyOffset = 1;
    if (text === this._currentHistoryItem()) {
      return;
    }
    this._data.push(text);
  }

  /**
   * Pushes the current (uncommitted) text into the history.
   */
  _pushCurrentText(currentText: string): void {
    if (this._uncommittedIsTop) {
      this._data.pop();
    }  // Throw away obsolete uncommitted text.
    this._uncommittedIsTop = true;
    this._data.push(currentText);
  }

  previous(currentText: string): string|undefined {
    if (this._historyOffset > this._data.length) {
      return undefined;
    }
    if (this._historyOffset === 1) {
      this._pushCurrentText(currentText);
    }
    ++this._historyOffset;
    return this._currentHistoryItem();
  }

  next(): string|undefined {
    if (this._historyOffset === 1) {
      return undefined;
    }
    --this._historyOffset;
    return this._currentHistoryItem();
  }

  _currentHistoryItem(): string|undefined {
    return this._data[this._data.length - this._historyOffset];
  }
}

export const enum Events {
  TextChanged = 'TextChanged',
}