// Copyright (c) 2020 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.

import * as Common from '../../core/common/common.js';
import * as i18n from '../../core/i18n/i18n.js';
import * as UI from '../../ui/legacy/legacy.js';
import * as VisualLogging from '../../ui/visual_logging/visual_logging.js';

import * as LinearMemoryInspectorComponents from './components/components.js';
import {type LazyUint8Array, LinearMemoryInspectorController} from './LinearMemoryInspectorController.js';

const UIStrings = {
  /**
   *@description Label in the Linear Memory inspector tool that serves as a placeholder if no inspections are open (i.e. nothing to see here).
   *             Inspection hereby refers to viewing, navigating and understanding the memory through this tool.
   */
  noOpenInspections: 'No open inspections',
};
const str_ = i18n.i18n.registerUIStrings('panels/linear_memory_inspector/LinearMemoryInspectorPane.ts', UIStrings);
const i18nString = i18n.i18n.getLocalizedString.bind(undefined, str_);
let inspectorInstance: LinearMemoryInspectorPane;

export class LinearMemoryInspectorPane extends Common.ObjectWrapper.eventMixin<EventTypes, typeof UI.Widget.VBox>(
    UI.Widget.VBox) {
  readonly #tabbedPane: UI.TabbedPane.TabbedPane;

  constructor() {
    super(false);
    this.element.setAttribute('jslog', `${VisualLogging.panel('linear-memory-inspector').track({resize: true})}`);
    const placeholder = document.createElement('div');
    placeholder.textContent = i18nString(UIStrings.noOpenInspections);
    placeholder.style.display = 'flex';
    this.#tabbedPane = new UI.TabbedPane.TabbedPane();
    this.#tabbedPane.setPlaceholderElement(placeholder);
    this.#tabbedPane.setCloseableTabs(true);
    this.#tabbedPane.setAllowTabReorder(true, true);
    this.#tabbedPane.addEventListener(UI.TabbedPane.Events.TabClosed, this.#tabClosed, this);
    this.#tabbedPane.show(this.contentElement);
    this.#tabbedPane.headerElement().setAttribute(
        'jslog', `${VisualLogging.toolbar().track({keydown: 'ArrowUp|ArrowLeft|ArrowDown|ArrowRight|Enter|Space'})}`);
  }

  static instance(): LinearMemoryInspectorPane {
    if (!inspectorInstance) {
      inspectorInstance = new LinearMemoryInspectorPane();
    }
    return inspectorInstance;
  }

  #tabView(tabId: string): LinearMemoryInspectorView {
    const view = this.#tabbedPane.tabView(tabId);
    if (view === null) {
      throw new Error(`No linear memory inspector view for the given tab id: ${tabId}`);
    }
    return view as LinearMemoryInspectorView;
  }

  create(tabId: string, title: string, arrayWrapper: LazyUint8Array, address?: number): void {
    const inspectorView = new LinearMemoryInspectorView(arrayWrapper, address, tabId);
    this.#tabbedPane.appendTab(tabId, title, inspectorView, undefined, false, true);
    this.#tabbedPane.selectTab(tabId);
  }

  close(tabId: string): void {
    this.#tabbedPane.closeTab(tabId, false);
  }

  reveal(tabId: string, address?: number): void {
    const view = this.#tabView(tabId);

    if (address !== undefined) {
      view.updateAddress(address);
    }
    this.refreshView(tabId);
    this.#tabbedPane.selectTab(tabId);
  }

  refreshView(tabId: string): void {
    const view = this.#tabView(tabId);
    view.refreshData();
  }

  #tabClosed(event: Common.EventTarget.EventTargetEvent<UI.TabbedPane.EventData>): void {
    const {tabId} = event.data;
    this.dispatchEventToListeners(Events.VIEW_CLOSED, tabId);
  }
}

export const enum Events {
  VIEW_CLOSED = 'ViewClosed',
}

export interface EventTypes {
  [Events.VIEW_CLOSED]: string;
}

export class LinearMemoryInspectorView extends UI.Widget.VBox {
  #memoryWrapper: LazyUint8Array;
  #address: number;
  #tabId: string;
  #inspector: LinearMemoryInspectorComponents.LinearMemoryInspector.LinearMemoryInspector;
  firstTimeOpen: boolean;
  readonly #hideValueInspector: boolean;

  constructor(
      memoryWrapper: LazyUint8Array, address: number|undefined = 0, tabId: string, hideValueInspector?: boolean) {
    super(false);

    if (address < 0 || address >= memoryWrapper.length()) {
      throw new Error('Requested address is out of bounds.');
    }

    this.#memoryWrapper = memoryWrapper;
    this.#address = address;
    this.#tabId = tabId;
    this.#hideValueInspector = Boolean(hideValueInspector);
    this.#inspector = new LinearMemoryInspectorComponents.LinearMemoryInspector.LinearMemoryInspector();
    this.#inspector.addEventListener(
        LinearMemoryInspectorComponents.LinearMemoryInspector.MemoryRequestEvent.eventName,
        (event: LinearMemoryInspectorComponents.LinearMemoryInspector.MemoryRequestEvent) => {
          this.#memoryRequested(event);
        });
    this.#inspector.addEventListener(
        LinearMemoryInspectorComponents.LinearMemoryInspector.AddressChangedEvent.eventName,
        (event: LinearMemoryInspectorComponents.LinearMemoryInspector.AddressChangedEvent) => {
          this.updateAddress(event.data);
        });
    this.#inspector.addEventListener(
        LinearMemoryInspectorComponents.LinearMemoryInspector.SettingsChangedEvent.eventName,
        (event: LinearMemoryInspectorComponents.LinearMemoryInspector.SettingsChangedEvent) => {
          // Stop event from bubbling up, since no element further up needs the event.
          event.stopPropagation();
          this.saveSettings(event.data);
        });
    this.#inspector.addEventListener(
        LinearMemoryInspectorComponents.LinearMemoryHighlightChipList.DeleteMemoryHighlightEvent.eventName,
        (event: LinearMemoryInspectorComponents.LinearMemoryHighlightChipList.DeleteMemoryHighlightEvent) => {
          LinearMemoryInspectorController.instance().removeHighlight(this.#tabId, event.data);
          this.refreshData();
        });
    this.contentElement.appendChild(this.#inspector);
    this.firstTimeOpen = true;
  }

  override wasShown(): void {
    this.refreshData();
  }

  saveSettings(settings: LinearMemoryInspectorComponents.LinearMemoryInspector.Settings): void {
    LinearMemoryInspectorController.instance().saveSettings(settings);
  }

  updateAddress(address: number): void {
    if (address < 0 || address >= this.#memoryWrapper.length()) {
      throw new Error('Requested address is out of bounds.');
    }
    this.#address = address;
  }

  refreshData(): void {
    void LinearMemoryInspectorController.getMemoryForAddress(this.#memoryWrapper, this.#address).then(({
                                                                                                        memory,
                                                                                                        offset,
                                                                                                      }) => {
      let valueTypes;
      let valueTypeModes;
      let endianness;
      if (this.firstTimeOpen) {
        const settings = LinearMemoryInspectorController.instance().loadSettings();
        valueTypes = settings.valueTypes;
        valueTypeModes = settings.modes;
        endianness = settings.endianness;
        this.firstTimeOpen = false;
      }
      this.#inspector.data = {
        memory,
        address: this.#address,
        memoryOffset: offset,
        outerMemoryLength: this.#memoryWrapper.length(),
        valueTypes,
        valueTypeModes,
        endianness,
        highlightInfo: this.#getHighlightInfo(),
        hideValueInspector: this.#hideValueInspector,
      };
    });
  }

  #memoryRequested(event: LinearMemoryInspectorComponents.LinearMemoryInspector.MemoryRequestEvent): void {
    const {start, end, address} = event.data;
    if (address < start || address >= end) {
      throw new Error('Requested address is out of bounds.');
    }

    void LinearMemoryInspectorController.getMemoryRange(this.#memoryWrapper, start, end).then(memory => {
      this.#inspector.data = {
        memory,
        address,
        memoryOffset: start,
        outerMemoryLength: this.#memoryWrapper.length(),
        highlightInfo: this.#getHighlightInfo(),
        hideValueInspector: this.#hideValueInspector,
      };
    });
  }

  #getHighlightInfo(): LinearMemoryInspectorComponents.LinearMemoryViewerUtils.HighlightInfo|undefined {
    const highlightInfo = LinearMemoryInspectorController.instance().getHighlightInfo(this.#tabId);
    if (highlightInfo !== undefined) {
      if (highlightInfo.startAddress < 0 || highlightInfo.startAddress >= this.#memoryWrapper.length()) {
        throw new Error('HighlightInfo start address is out of bounds.');
      }
      if (highlightInfo.size <= 0) {
        throw new Error('Highlight size must be a positive number.');
      }
    }
    return highlightInfo;
  }
}