// Copyright 2023 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
import * as i18n from '../../core/i18n/i18n.js';
import * as Trace from '../../models/trace/trace.js';
import * as PerfUI from '../../ui/legacy/components/perf_ui/perf_ui.js';
import * as ThemeSupport from '../../ui/legacy/theme_support/theme_support.js';

import {buildGroupStyle, buildTrackHeader} from './AppenderUtils.js';
import {
  type CompatibilityTracksAppender,
  type TrackAppender,
  type TrackAppenderName,
  VisualLoggingTrackName,
} from './CompatibilityTracksAppender.js';

const UIStrings = {
  /**
   * @description Text in Timeline Flame Chart Data Provider of the Performance panel
   */
  gpu: 'GPU',
} as const;

const str_ = i18n.i18n.registerUIStrings('panels/timeline/GPUTrackAppender.ts', UIStrings);
const i18nString = i18n.i18n.getLocalizedString.bind(undefined, str_);

export class GPUTrackAppender implements TrackAppender {
  readonly appenderName: TrackAppenderName = 'GPU';

  #compatibilityBuilder: CompatibilityTracksAppender;
  #parsedTrace: Readonly<Trace.TraceModel.ParsedTrace>;

  constructor(compatibilityBuilder: CompatibilityTracksAppender, parsedTrace: Trace.TraceModel.ParsedTrace) {
    this.#compatibilityBuilder = compatibilityBuilder;
    this.#parsedTrace = parsedTrace;
  }

  /**
   * Appends into the flame chart data the data corresponding to the
   * GPU track.
   * @param trackStartLevel the horizontal level of the flame chart events where
   * the track's events will start being appended.
   * @param expanded whether the track should be rendered expanded.
   * @returns the first available level to append more data after having
   * appended the track's events.
   */
  appendTrackAtLevel(trackStartLevel: number, expanded?: boolean|undefined): number {
    const gpuEvents = this.#parsedTrace.data.GPU.mainGPUThreadTasks;
    if (gpuEvents.length === 0) {
      return trackStartLevel;
    }
    this.#appendTrackHeaderAtLevel(trackStartLevel, expanded);
    return this.#compatibilityBuilder.appendEventsAtLevel(gpuEvents, trackStartLevel, this);
  }

  /**
   * Adds into the flame chart data the header corresponding to the
   * GPU track. A header is added in the shape of a group in the
   * flame chart data. A group has a predefined style and a reference
   * to the definition of the legacy track (which should be removed
   * in the future).
   * @param currentLevel the flame chart level at which the header is
   * appended.
   * @param expanded whether the track should be rendered expanded.
   */
  #appendTrackHeaderAtLevel(currentLevel: number, expanded?: boolean): void {
    const style = buildGroupStyle({collapsible: PerfUI.FlameChart.GroupCollapsibleState.NEVER});
    const group = buildTrackHeader(
        VisualLoggingTrackName.GPU, currentLevel, i18nString(UIStrings.gpu), style, /* selectable= */ true, expanded);
    this.#compatibilityBuilder.registerTrackForGroup(group, this);
  }

  /*
    ------------------------------------------------------------------------------------
     The following methods  are invoked by the flame chart renderer to query features about
     events on rendering.
    ------------------------------------------------------------------------------------
  */

  /**
   * Gets the color an event added by this appender should be rendered with.
   */
  colorForEvent(event: Trace.Types.Events.Event): string {
    if (!Trace.Types.Events.isGPUTask(event)) {
      throw new Error(`Unexpected GPU Task: The event's type is '${event.name}'`);
    }
    return ThemeSupport.ThemeSupport.instance().getComputedValue('--app-color-painting');
  }
}