// Copyright 2024 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 i18n from '../../../../core/i18n/i18n.js';
import type {ThirdPartiesInsightModel} from '../../../../models/trace/insights/ThirdParties.js';
import * as Trace from '../../../../models/trace/trace.js';
import * as Lit from '../../../../ui/lit/lit.js';
import type * as Overlays from '../../overlays/overlays.js';

import {BaseInsightComponent} from './BaseInsightComponent.js';
import {createLimitedRows, renderOthersLabel, type RowLimitAggregator} from './Table.js';

const {UIStrings, i18nString} = Trace.Insights.Models.ThirdParties;

const {html} = Lit;

const MAX_TO_SHOW = 5;

export class ThirdParties extends BaseInsightComponent<ThirdPartiesInsightModel> {
  static override readonly litTagName = Lit.StaticHtml.literal`devtools-performance-third-parties`;
  override internalName = 'third-parties';

  override createOverlays(): Overlays.Overlays.TimelineOverlay[] {
    if (!this.model) {
      return [];
    }

    const overlays: Overlays.Overlays.TimelineOverlay[] = [];
    const summaries = this.model.entitySummaries ?? [];
    for (const summary of summaries) {
      if (summary.entity === this.model.firstPartyEntity) {
        continue;
      }

      const summaryOverlays = this.#createOverlaysForSummary(summary);
      overlays.push(...summaryOverlays);
    }
    return overlays;
  }

  #createOverlaysForSummary(summary: Trace.Extras.ThirdParties.EntitySummary): Overlays.Overlays.TimelineOverlay[] {
    const overlays = [];
    for (const event of summary.relatedEvents) {
      // The events found for a third party can be vast, as they gather every
      // single main thread task along with everything else on the page. If the
      // main thread is busy with large icicles, we can easily create tens of
      // thousands of overlays. Therefore, only create overlays for events of at least 1ms.
      if (event.dur === undefined || event.dur < 1_000) {
        continue;
      }

      const overlay: Overlays.Overlays.TimelineOverlay = {
        type: 'ENTRY_OUTLINE',
        entry: event,
        outlineReason: 'INFO',
      };
      overlays.push(overlay);
    }
    return overlays;
  }

  #mainThreadTimeAggregator: RowLimitAggregator<Trace.Extras.ThirdParties.EntitySummary> = {
    mapToRow: summary => ({
      values: [summary.entity.name, i18n.TimeUtilities.millisToString(summary.mainThreadTime)],
      overlays: this.#createOverlaysForSummary(summary),
    }),
    createAggregatedTableRow:
        remaining => {
          const totalMainThreadTime = remaining.reduce<Trace.Types.Timing.Milli>(
              (acc, summary) => Trace.Types.Timing.Milli(acc + summary.mainThreadTime), Trace.Types.Timing.Milli(0));
          return {
            values: [renderOthersLabel(remaining.length), i18n.TimeUtilities.millisToString(totalMainThreadTime)],
            overlays: remaining.flatMap(summary => this.#createOverlaysForSummary(summary) ?? []),
          };
        },
  };

  #transferSizeAggregator: RowLimitAggregator<Trace.Extras.ThirdParties.EntitySummary> = {
    mapToRow: summary => ({
      values: [summary.entity.name, i18n.ByteUtilities.formatBytesToKb(summary.transferSize)],
      overlays: this.#createOverlaysForSummary(summary),
    }),
    createAggregatedTableRow:
        remaining => {
          const totalBytes = remaining.reduce((acc, summary) => acc + summary.transferSize, 0);
          return {
            values: [renderOthersLabel(remaining.length), i18n.ByteUtilities.formatBytesToKb(totalBytes)],
            overlays: remaining.flatMap(summary => this.#createOverlaysForSummary(summary) ?? []),
          };
        },
  };

  override renderContent(): Lit.LitTemplate {
    if (!this.model) {
      return Lit.nothing;
    }

    let result = this.model.entitySummaries ?? [];

    if (this.model.firstPartyEntity) {
      result = result.filter(s => s.entity !== this.model?.firstPartyEntity || null);
    }
    if (!result.length) {
      return html`<div class="insight-section">${i18nString(UIStrings.noThirdParties)}</div>`;
    }

    const topTransferSizeEntries = result.toSorted((a, b) => b.transferSize - a.transferSize);
    const topMainThreadTimeEntries = result.toSorted((a, b) => b.mainThreadTime - a.mainThreadTime);

    const sections = [];
    if (topTransferSizeEntries.length) {
      const rows = createLimitedRows(topTransferSizeEntries, this.#transferSizeAggregator, MAX_TO_SHOW);
      // clang-format off
      sections.push(html`
        <div class="insight-section">
          <devtools-performance-table
            .data=${{
              insight: this,
              headers: [i18nString(UIStrings.columnThirdParty), i18nString(UIStrings.columnTransferSize)],
              rows,
            }}>
          </devtools-performance-table>
        </div>
      `);
      // clang-format on
    }

    if (topMainThreadTimeEntries.length) {
      const rows = createLimitedRows(topMainThreadTimeEntries, this.#mainThreadTimeAggregator, MAX_TO_SHOW);
      // clang-format off
      sections.push(html`
        <div class="insight-section">
          <devtools-performance-table
            .data=${{
              insight: this,
              headers: [i18nString(UIStrings.columnThirdParty), i18nString(UIStrings.columnMainThreadTime)],
              rows,
            }}>
          </devtools-performance-table>
        </div>
      `);
      // clang-format on
    }

    return html`${sections}`;
  }
}

declare global {
  interface HTMLElementTagNameMap {
    'devtools-performance-third-parties': ThirdParties;
  }
}

customElements.define('devtools-performance-third-parties', ThirdParties);