// 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.
/* eslint-disable @devtools/no-imperative-dom-api */

import {assertNotNullOrUndefined} from '../../core/platform/platform.js';

import type {Loggable} from './Loggable.js';
import {type LoggingConfig, VisualElements} from './LoggingConfig.js';
import {getLoggingState, type LoggingState} from './LoggingState.js';

let veDebuggingEnabled = false;
let debugOverlay: HTMLElement|null = null;
let debugPopover: HTMLElement|null = null;
const highlightedElements: HTMLElement[] = [];
let onInspect: ((query: string) => void)|undefined = undefined;

function ensureDebugOverlay(): void {
  if (!debugOverlay) {
    debugOverlay = document.createElement('div');
    debugOverlay.style.position = 'fixed';
    debugOverlay.style.top = '0';
    debugOverlay.style.left = '0';
    debugOverlay.style.width = '100vw';
    debugOverlay.style.height = '100vh';
    debugOverlay.style.zIndex = '100000';
    debugOverlay.style.pointerEvents = 'none';
    document.body.appendChild(debugOverlay);

    debugPopover = document.createElement('div');
    debugPopover.classList.add('ve-debug');
    debugPopover.style.position = 'absolute';
    debugPopover.style.background = 'var(--sys-color-cdt-base-container)';
    debugPopover.style.borderRadius = '2px';
    debugPopover.style.padding = '8px';
    debugPopover.style.boxShadow = 'var(--drop-shadow)';
    debugOverlay.appendChild(debugPopover);
  }
}

export function setVeDebuggingEnabled(enabled: boolean, inspect?: (query: string) => void): void {
  veDebuggingEnabled = enabled;
  if (enabled) {
    ensureDebugOverlay();
  }
  onInspect = inspect;
  if (!enabled) {
    highlightElement(null);
  }
}

// @ts-expect-error
globalThis.setVeDebuggingEnabled = setVeDebuggingEnabled;

let highlightedVeKey: string|null = null;

export function setHighlightedVe(veKey: string|null): void {
  ensureDebugOverlay();
  highlightedVeKey = veKey;
  highlightElement(null);
}

function maybeHighlightElement(element: HTMLElement, highlightedKey: string): void {
  highlightedKey = highlightedKey.trim();
  let state = getLoggingState(element);
  let trailingVe = state?.config?.ve ? VisualElements[state?.config?.ve] : null;
  while (state && highlightedKey) {
    const currentKey = elementKey(state.config);
    if (highlightedKey.endsWith(currentKey)) {
      highlightedKey = highlightedKey.slice(0, -currentKey.length).trim();
    } else if (trailingVe && highlightedKey.endsWith(trailingVe)) {
      highlightedKey = highlightedKey.slice(0, -trailingVe.length).trim();
      trailingVe = null;
    } else {
      break;
    }
    state = state.parent;
    if (state && !highlightedKey.endsWith('>')) {
      break;
    }
    highlightedKey = highlightedKey.slice(0, -1).trim();
  }
  if (!highlightedKey && !state) {
    highlightElement(element, true);
  }
}

export function processForDebugging(loggable: Loggable): void {
  if (highlightedVeKey && loggable instanceof HTMLElement) {
    maybeHighlightElement(loggable, highlightedVeKey);
  }
  const loggingState = getLoggingState(loggable);
  if (!veDebuggingEnabled || !loggingState || loggingState.processedForDebugging) {
    return;
  }
  if (loggable instanceof HTMLElement) {
    processElementForDebugging(loggable, loggingState);
  }
}

function showDebugPopover(content: string, rect?: DOMRect): void {
  if (!debugPopover) {
    return;
  }

  // Set these first so we get the correct information from
  // getBoundingClientRect
  debugPopover.style.display = 'block';
  debugPopover.textContent = content;

  if (rect) {
    const debugPopoverReact = debugPopover.getBoundingClientRect();

    // If there is no space under the element
    // render render it above the element
    if (window.innerHeight < rect.bottom + debugPopoverReact.height + 8) {
      debugPopover.style.top = `${rect.top - debugPopoverReact.height - 8}px`;
    } else {
      debugPopover.style.top = `${rect.bottom + 8}px`;
    }

    // If the element will go outside the viewport on the right
    // render it with it's and at the viewport end.
    if (window.innerWidth < rect.left + debugPopoverReact.width) {
      debugPopover.style.right = '0px';
      debugPopover.style.left = '';
    } else {
      debugPopover.style.right = '';
      debugPopover.style.left = `${rect.left}px`;
    }
  }
}

function highlightElement(element: HTMLElement|null, allowMultiple = false): void {
  if (highlightedElements.length > 0 && !allowMultiple && debugOverlay) {
    [...debugOverlay.children].forEach(e => {
      if (e !== debugPopover) {
        e.remove();
      }
    });
    highlightedElements.length = 0;
  }
  if (element && !highlightedElements.includes(element)) {
    assertNotNullOrUndefined(debugOverlay);
    const rect = element.getBoundingClientRect();
    const highlight = document.createElement('div');
    highlight.style.position = 'absolute';
    highlight.style.top = `${rect.top}px`;
    highlight.style.left = `${rect.left}px`;
    highlight.style.width = `${rect.width}px`;
    highlight.style.height = `${rect.height}px`;
    highlight.style.background = 'rgb(71 140 222 / 50%)';
    highlight.style.border = 'dashed 1px #7327C6';
    highlight.style.pointerEvents = 'none';
    debugOverlay.appendChild(highlight);
    highlightedElements.push(element);
  }
}

function processElementForDebugging(element: HTMLElement, loggingState: LoggingState): void {
  if (element.tagName === 'OPTION') {
    if (loggingState.parent?.selectOpen && debugPopover) {
      debugPopover.innerHTML += '<br>' + debugString(loggingState.config);
      loggingState.processedForDebugging = true;
    }
  } else {
    element.addEventListener('mousedown', event => {
      if (highlightedElements.length && debugPopover && veDebuggingEnabled) {
        event.stopImmediatePropagation();
        event.preventDefault();
      }
    }, {capture: true});
    element.addEventListener('click', event => {
      if (highlightedElements.includes(event.currentTarget as HTMLElement) && debugPopover && veDebuggingEnabled) {
        onInspect?.(debugPopover.textContent || '');
        event.stopImmediatePropagation();
        event.preventDefault();
      }
    }, {capture: true});
    element.addEventListener('mouseenter', () => {
      if (!veDebuggingEnabled) {
        return;
      }
      highlightElement(element);
      assertNotNullOrUndefined(debugPopover);
      const pathToRoot = [loggingState];
      let ancestor = loggingState.parent;
      while (ancestor) {
        pathToRoot.unshift(ancestor);
        ancestor = ancestor.parent;
      }
      showDebugPopover(pathToRoot.map(s => elementKey(s.config)).join(' > '), element.getBoundingClientRect());
    }, {capture: true});
    element.addEventListener('mouseleave', () => {
      element.style.backgroundColor = '';
      element.style.outline = '';
      assertNotNullOrUndefined(debugPopover);
      debugPopover.style.display = 'none';
    }, {capture: true});
    loggingState.processedForDebugging = true;
  }
}

type EventType = 'Click'|'Drag'|'Hover'|'Change'|'KeyDown'|'Resize'|'SettingAccess'|'FunctionCall';
export function processEventForDebugging(
    event: EventType, state: LoggingState|null, extraInfo?: EventAttributes): void {
  const format = localStorage.getItem('veDebugLoggingEnabled');
  if (!format) {
    return;
  }

  switch (format) {
    case DebugLoggingFormat.INTUITIVE:
      processEventForIntuitiveDebugging(event, state, extraInfo);
      break;
    case DebugLoggingFormat.TEST:
      processEventForTestDebugging(event, state, extraInfo);
      break;
    case DebugLoggingFormat.AD_HOC_ANALYSIS:
      processEventForAdHocAnalysisDebugging(event, state, extraInfo);
      break;
  }
}

export function processEventForIntuitiveDebugging(
    event: EventType, state: LoggingState|null, extraInfo?: EventAttributes): void {
  const entry: IntuitiveLogEntry = {
    event,
    ve: state ? VisualElements[state?.config.ve] : undefined,
    veid: state?.veid,
    context: state?.config.context,
    time: Date.now() - sessionStartTime,
    ...extraInfo,
  };
  deleteUndefinedFields(entry);
  maybeLogDebugEvent(entry);
}

export function processEventForTestDebugging(
    event: EventType, state: LoggingState|null, _extraInfo?: EventAttributes): void {
  if (event !== 'SettingAccess' && event !== 'FunctionCall' && event !== 'Resize') {
    lastImpressionLogEntry = null;
  }
  maybeLogDebugEvent({interaction: event, veid: state?.veid || 0});
  checkPendingEventExpectation();
}

export function processEventForAdHocAnalysisDebugging(
    event: EventType, state: LoggingState|null, extraInfo?: EventAttributes): void {
  const ve = state ? adHocAnalysisEntries.get(state.veid) : null;
  if (ve) {
    const interaction: AdHocAnalysisInteraction = {time: Date.now() - sessionStartTime, type: event, ...extraInfo};
    deleteUndefinedFields(interaction);
    ve.interactions.push(interaction);
  }
}

function deleteUndefinedFields<T>(entry: T): void {
  for (const stringKey in entry) {
    const key = stringKey as keyof T;
    if (typeof entry[key] === 'undefined') {
      delete entry[key];
    }
  }
}

export interface EventAttributes {
  context?: string;
  width?: number;
  height?: number;
  mouseButton?: number;
  doubleClick?: boolean;
  name?: string;
  numericValue?: number;
  stringValue?: string;
}

interface VisualElementAttributes {
  ve: string;
  veid: number;
  context?: string;
  width?: number;
  height?: number;
}

type IntuitiveLogEntry = {
  event?: EventType|'Impression'|'SessionStart',
  children?: IntuitiveLogEntry[],
  parent?: number,
  time?: number,
}&Partial<VisualElementAttributes>;

type AdHocAnalysisVisualElement = VisualElementAttributes&{
  parent?: AdHocAnalysisVisualElement,
};

type AdHocAnalysisInteraction = {
  type: EventType,
  time: number,
}&EventAttributes;

type AdHocAnalysisLogEntry = AdHocAnalysisVisualElement&{
  time: number,
  interactions: AdHocAnalysisInteraction[],
};

type TestLogEntry = {
  impressions: string[],
}|{
  interaction: string,
  veid?: number,
};

export function processImpressionsForDebugging(states: LoggingState[]): void {
  const format = localStorage.getItem('veDebugLoggingEnabled');
  switch (format) {
    case DebugLoggingFormat.INTUITIVE:
      processImpressionsForIntuitiveDebugLog(states);
      break;
    case DebugLoggingFormat.TEST:
      processImpressionsForTestDebugLog(states);
      break;
    case DebugLoggingFormat.AD_HOC_ANALYSIS:
      processImpressionsForAdHocAnalysisDebugLog(states);
      break;
    default:
  }
}

function processImpressionsForIntuitiveDebugLog(states: LoggingState[]): void {
  const impressions = new Map<number, IntuitiveLogEntry>();
  for (const state of states) {
    const entry: IntuitiveLogEntry = {
      event: 'Impression',
      ve: VisualElements[state.config.ve],
      context: state?.config.context,
      width: state.size.width,
      height: state.size.height,
      veid: state.veid,
    };
    deleteUndefinedFields(entry);

    impressions.set(state.veid, entry);
    if (!state.parent || !impressions.has(state.parent?.veid)) {
      entry.parent = state.parent?.veid;
    } else {
      const parent = impressions.get(state.parent?.veid) as IntuitiveLogEntry;
      parent.children = parent.children || [];
      parent.children.push(entry);
    }
  }

  const entries = [...impressions.values()].filter(i => 'parent' in i);
  if (entries.length === 1) {
    entries[0].time = Date.now() - sessionStartTime;
    maybeLogDebugEvent(entries[0]);
  } else {
    maybeLogDebugEvent({event: 'Impression', children: entries, time: Date.now() - sessionStartTime});
  }
}

const veTestKeys = new Map<number, string>();
let lastImpressionLogEntry: {impressions: string[]}|null = null;

function processImpressionsForTestDebugLog(states: LoggingState[]): void {
  if (!lastImpressionLogEntry) {
    lastImpressionLogEntry = {impressions: []};
    veDebugEventsLog.push(lastImpressionLogEntry);
  }
  for (const state of states) {
    let key = '';
    if (state.parent) {
      key = (veTestKeys.get(state.parent.veid) || '<UNKNOWN>') + ' > ';
    }
    key += VisualElements[state.config.ve];
    if (state.config.context) {
      key += ': ' + state.config.context;
    }
    veTestKeys.set(state.veid, key);
    lastImpressionLogEntry.impressions.push(key);
  }
  checkPendingEventExpectation();
}

const adHocAnalysisEntries = new Map<number, AdHocAnalysisLogEntry>();

function processImpressionsForAdHocAnalysisDebugLog(states: LoggingState[]): void {
  for (const state of states) {
    const buildVe = (state: LoggingState): AdHocAnalysisVisualElement => {
      const ve: AdHocAnalysisVisualElement = {
        ve: VisualElements[state.config.ve],
        veid: state.veid,
        width: state.size?.width,
        height: state.size?.height,
        context: state.config.context,
      };
      deleteUndefinedFields(ve);
      if (state.parent) {
        ve.parent = buildVe(state.parent);
      }
      return ve;
    };
    const entry = {...buildVe(state), interactions: [], time: Date.now() - sessionStartTime};
    adHocAnalysisEntries.set(state.veid, entry);
    maybeLogDebugEvent(entry);
  }
}

function elementKey(config: LoggingConfig): string {
  return `${VisualElements[config.ve]}${config.context ? `: ${config.context}` : ''}`;
}

export function debugString(config: LoggingConfig): string {
  const components = [VisualElements[config.ve]];
  if (config.context) {
    components.push(`context: ${config.context}`);
  }
  if (config.parent) {
    components.push(`parent: ${config.parent}`);
  }
  if (config.track) {
    components.push(`track: ${
        Object.entries(config.track)
            .map(([key, value]) => `${key}${typeof value === 'string' ? `: ${value}` : ''}`)
            .join(', ')}`);
  }
  return components.join('; ');
}

const veDebugEventsLog: Array<IntuitiveLogEntry|AdHocAnalysisLogEntry|TestLogEntry> = [];

function maybeLogDebugEvent(entry: IntuitiveLogEntry|AdHocAnalysisLogEntry|TestLogEntry): void {
  const format = localStorage.getItem('veDebugLoggingEnabled');
  if (!format) {
    return;
  }
  veDebugEventsLog.push(entry);
  if (format === DebugLoggingFormat.INTUITIVE) {
    // eslint-disable-next-line no-console
    console.info('VE Debug:', entry);
  }
}

export const enum DebugLoggingFormat {
  INTUITIVE = 'Intuitive',
  TEST = 'Test',
  AD_HOC_ANALYSIS = 'AdHocAnalysis',
}

export function setVeDebugLoggingEnabled(enabled: boolean, format = DebugLoggingFormat.INTUITIVE): void {
  if (enabled) {
    localStorage.setItem('veDebugLoggingEnabled', format);
  } else {
    localStorage.removeItem('veDebugLoggingEnabled');
  }
}

function findVeDebugImpression(veid: number, includeAncestorChain?: boolean): IntuitiveLogEntry|undefined {
  const findImpression = (entry: IntuitiveLogEntry): IntuitiveLogEntry|undefined => {
    if (entry.event === 'Impression' && entry.veid === veid) {
      return entry;
    }
    let i = 0;
    for (const childEntry of entry.children || []) {
      const matchingEntry = findImpression(childEntry);
      if (matchingEntry) {
        if (includeAncestorChain) {
          const children = [];
          children[i] = matchingEntry;
          return {...entry, children};
        }
        return matchingEntry;
      }
      ++i;
    }
    return undefined;
  };
  return findImpression({children: veDebugEventsLog as IntuitiveLogEntry[]});
}

function fieldValuesForSql<T>(
    obj: T,
    fields: {strings: ReadonlyArray<keyof T>, numerics: ReadonlyArray<keyof T>, booleans: ReadonlyArray<keyof T>}):
    string {
  return [
    ...fields.strings.map(f => obj[f] ? `"${obj[f]}"` : '$NullString'),
    ...fields.numerics.map(f => obj[f] ?? 'null'),
    ...fields.booleans.map(f => obj[f] ?? '$NullBool'),
  ].join(', ');
}

function exportAdHocAnalysisLogForSql(): void {
  const VE_FIELDS = {
    strings: ['ve', 'context'] as const,
    numerics: ['veid', 'width', 'height'] as const,
    booleans: [] as const,
  };
  const INTERACTION_FIELDS = {
    strings: ['type', 'context'] as const,
    numerics: ['width', 'height', 'mouseButton', 'time'] as const,
    booleans: ['width', 'height', 'mouseButton', 'time'] as const,
  };

  const fieldsDefsForSql = (fields: string[]): string => fields.map((f, i) => `$${i + 1} as ${f}`).join(', ');

  const veForSql = (e: AdHocAnalysisVisualElement): string =>
      `$VeFields(${fieldValuesForSql(e, VE_FIELDS)}, ${e.parent ? `STRUCT(${veForSql(e.parent)})` : null})`;

  const interactionForSql = (i: AdHocAnalysisInteraction): string =>
      `$Interaction(${fieldValuesForSql(i, INTERACTION_FIELDS)})`;

  const entryForSql = (e: AdHocAnalysisLogEntry): string =>
      `$Entry(${veForSql(e)}, ([${e.interactions.map(interactionForSql).join(', ')}]), ${e.time})`;

  const entries = veDebugEventsLog as AdHocAnalysisLogEntry[];

  // eslint-disable-next-line no-console
  console.log(`
DEFINE MACRO NullString CAST(null AS STRING);
DEFINE MACRO NullBool CAST(null AS BOOL);
DEFINE MACRO VeFields ${fieldsDefsForSql([
    ...VE_FIELDS.strings,
    ...VE_FIELDS.numerics,
    'parent',
  ])};
DEFINE MACRO Interaction STRUCT(${
      fieldsDefsForSql([
        ...INTERACTION_FIELDS.strings,
        ...INTERACTION_FIELDS.numerics,
        ...INTERACTION_FIELDS.booleans,
      ])});
DEFINE MACRO Entry STRUCT($1, $2 AS interactions, $3 AS time);

// This fake entry put first fixes nested struct fields names being lost
DEFINE MACRO FakeVeFields $VeFields("", $NullString, 0, 0, 0, $1);
DEFINE MACRO FakeVe STRUCT($FakeVeFields($1));
DEFINE MACRO FakeEntry $Entry($FakeVeFields($FakeVe($FakeVe($FakeVe($FakeVe($FakeVe($FakeVe($FakeVe(null)))))))), ([]), 0);

WITH
  processed_logs AS (
      SELECT * FROM UNNEST([
        $FakeEntry,
        ${entries.map(entryForSql).join(', \n')}
      ])
    )


SELECT * FROM processed_logs;`);
}

type StateFlowNode = {
  type: 'Session',
  children: StateFlowNode[],
}|({type: 'Impression', children: StateFlowNode[], time: number}&AdHocAnalysisVisualElement)|AdHocAnalysisInteraction;

type StateFlowMutation = (AdHocAnalysisLogEntry|(AdHocAnalysisInteraction&{veid: number}));

function getStateFlowMutations(): StateFlowMutation[] {
  const mutations: StateFlowMutation[] = [];
  for (const entry of (veDebugEventsLog as AdHocAnalysisLogEntry[])) {
    mutations.push(entry);
    const veid = entry.veid;
    for (const interaction of entry.interactions) {
      mutations.push({...interaction, veid});
    }
  }
  mutations.sort((e1, e2) => e1.time - e2.time);
  return mutations;
}

class StateFlowElementsByArea {
  #data = new Map<number, AdHocAnalysisVisualElement>();

  add(e: AdHocAnalysisVisualElement): void {
    this.#data.set(e.veid, e);
  }

  get(veid: number): AdHocAnalysisVisualElement|undefined {
    return this.#data.get(veid);
  }

  getArea(e: AdHocAnalysisVisualElement): number {
    let area = (e.width || 0) * (e.height || 0);
    const parent = e.parent ? this.#data.get(e.parent?.veid) : null;
    if (!parent) {
      return area;
    }
    const parentArea = this.getArea(parent);
    if (area > parentArea) {
      area = parentArea;
    }
    return area;
  }

  get data(): readonly AdHocAnalysisVisualElement[] {
    return [...this.#data.values()].filter(e => this.getArea(e)).sort((e1, e2) => this.getArea(e2) - this.getArea(e1));
  }
}

function updateStateFlowTree(
    rootNode: StateFlowNode, elements: StateFlowElementsByArea, time: number,
    interactions: AdHocAnalysisInteraction[]): void {
  let node = rootNode;
  for (const element of elements.data) {
    if (!('children' in node)) {
      return;
    }
    let nextNode = node.children[node.children.length - 1];
    const nextNodeId = nextNode?.type === 'Impression' ? nextNode.veid : null;
    if (nextNodeId !== element.veid) {
      node.children.push(...interactions);
      interactions.length = 0;
      nextNode = {type: 'Impression', ve: element.ve, veid: element.veid, context: element.context, time, children: []};
      node.children.push(nextNode);
    }
    node = nextNode;
  }
}

function normalizeNode(node: StateFlowNode): void {
  if (node.type !== 'Impression') {
    return;
  }
  while (node.children.length === 1) {
    if (node.children[0].type === 'Impression') {
      node.children = node.children[0].children;
    }
  }
  for (const child of node.children) {
    normalizeNode(child);
  }
}

function buildStateFlow(): StateFlowNode {
  const mutations = getStateFlowMutations();
  const elements = new StateFlowElementsByArea();
  const rootNode: StateFlowNode = {type: 'Session', children: []};

  let time = mutations[0].time;
  const interactions: AdHocAnalysisInteraction[] = [];
  for (const mutation of mutations) {
    if (mutation.time > time + 1000) {
      updateStateFlowTree(rootNode, elements, time, interactions);
      interactions.length = 0;
    }
    if (!('type' in mutation)) {
      elements.add(mutation);
    } else if (mutation.type === 'Resize') {
      const element = elements.get(mutation.veid);
      if (!element) {
        continue;
      }
      const oldArea = elements.getArea(element);
      element.width = mutation.width;
      element.height = mutation.height;
      if (elements.getArea(element) !== 0 && oldArea !== 0) {
        interactions.push(mutation);
      }
    } else {
      interactions.push(mutation);
    }
    time = mutation.time;
  }
  updateStateFlowTree(rootNode, elements, time, interactions);

  normalizeNode(rootNode);
  return rootNode;
}

let sessionStartTime: number = Date.now();

export function processStartLoggingForDebugging(): void {
  sessionStartTime = Date.now();
  if (localStorage.getItem('veDebugLoggingEnabled') === DebugLoggingFormat.INTUITIVE) {
    maybeLogDebugEvent({event: 'SessionStart'});
  }
}

/**
 * Compares the 'actual' log entry against the 'expected'.
 * For impressions events to match, all expected impressions need to be present
 * in the actual event. Unexpected impressions in the actual event are ignored.
 * Interaction events need to match exactly.
 **/
function compareVeEvents(actual: TestLogEntry, expected: TestLogEntry): boolean {
  if ('interaction' in expected && 'interaction' in actual) {
    const actualString = formatInteraction(actual);
    return expected.interaction === actualString;
  }
  if ('impressions' in expected && 'impressions' in actual) {
    const actualSet = new Set(actual.impressions);
    const expectedSet = new Set(expected.impressions);
    const missing = [...expectedSet].filter(k => !actualSet.has(k));

    return !Boolean(missing.length);
  }
  return false;
}

interface PendingEventExpectation {
  expectedEvents: TestLogEntry[];
  missingEvents?: TestLogEntry[];
  unmatchedEvents: TestLogEntry[];
  success: () => void;
  fail: (arg0: Error) => void;
}

let pendingEventExpectation: PendingEventExpectation|null = null;

function formatImpressions(impressions: string[]): string {
  const result: string[] = [];
  let lastImpression = '';
  for (const impression of impressions.sort()) {
    if (impression === lastImpression) {
      continue;
    }
    while (!impression.startsWith(lastImpression)) {
      lastImpression = lastImpression.substr(0, lastImpression.lastIndexOf(' > '));
    }
    result.push(' '.repeat(lastImpression.length) + impression.substr(lastImpression.length));
    lastImpression = impression;
  }
  return result.join('\n');
}

const EVENT_EXPECTATION_TIMEOUT = 5000;

function formatInteraction(e: TestLogEntry): string {
  if ('interaction' in e) {
    if (e.veid !== undefined) {
      const key = veTestKeys.get(e.veid) || (e.veid ? '<UNKNOWN>' : '');
      return `${e.interaction}: ${key}`;
    }
    return e.interaction;
  }
  return '';
}

function formatVeEvents(events: TestLogEntry[]): string {
  return events
      .map(e => {
        if ('interaction' in e) {
          return formatInteraction(e);
        }
        return formatImpressions(e.impressions);
      })
      .join('\n');
}

/**
 * Verifies that VE events contains all the expected events in given order.
 * Unexpected VE events are ignored.
 **/
export async function expectVeEvents(expectedEvents: TestLogEntry[]): Promise<void> {
  if (pendingEventExpectation) {
    throw new Error('VE events expectation already set. Cannot set another one until the previous is resolved');
  }
  const {promise, resolve: success, reject: fail} = Promise.withResolvers<void>();
  pendingEventExpectation = {expectedEvents, success, fail, unmatchedEvents: []};
  checkPendingEventExpectation();

  const timeout = setTimeout(() => {
    if (pendingEventExpectation?.missingEvents?.length) {
      const allLogs = veDebugEventsLog.filter(ve => {
        if ('interaction' in ve) {
          // Very noisy in the error and not providing context
          return ve.interaction !== 'SettingAccess';
        }

        return true;
      });
      pendingEventExpectation.fail(new Error(`
Missing VE Events:
${formatVeEvents(pendingEventExpectation.missingEvents)}
Unmatched VE Events:
${formatVeEvents(pendingEventExpectation.unmatchedEvents)}
All events:
${JSON.stringify(allLogs, null, 2)}
`));
    }
  }, EVENT_EXPECTATION_TIMEOUT);

  return await promise.finally(() => {
    clearTimeout(timeout);
    pendingEventExpectation = null;
  });
}

let numMatchedEvents = 0;

function recordUnmatchedEvent(
    pendingExpectation: PendingEventExpectation, actualEvent: TestLogEntry, expectedEvent: TestLogEntry,
    matchedImpressions: Set<string>): void {
  const unmatched = {...actualEvent};
  if ('impressions' in unmatched && 'impressions' in expectedEvent) {
    unmatched.impressions = unmatched.impressions.filter(impression => {
      const matched = expectedEvent.impressions.includes(impression);
      if (matched) {
        matchedImpressions.add(impression);
      }
      return !matched;
    });
  }
  pendingExpectation.unmatchedEvents.push(unmatched);
}

function processMissingEvents(
    pendingExpectation: PendingEventExpectation, expectedEventIndex: number, matchedImpressions: Set<string>): void {
  pendingExpectation.missingEvents = pendingExpectation.expectedEvents.slice(expectedEventIndex);
  for (const event of pendingExpectation.missingEvents) {
    if ('impressions' in event) {
      event.impressions = event.impressions.filter(impression => !matchedImpressions.has(impression));
    }
  }
  pendingExpectation.missingEvents =
      pendingExpectation.missingEvents.filter(event => !('impressions' in event) || event.impressions.length > 0);
}

function checkPendingEventExpectation(): void {
  if (!pendingEventExpectation) {
    return;
  }
  const actualEvents = veDebugEventsLog as TestLogEntry[];
  let actualEventIndex = 0;
  let matchStarted = false;
  const matchedImpressions = new Set<string>();
  pendingEventExpectation.unmatchedEvents = [];

  for (let expectedEventIndex = 0; expectedEventIndex < pendingEventExpectation.expectedEvents.length;
       ++expectedEventIndex) {
    const expectedEvent = pendingEventExpectation.expectedEvents[expectedEventIndex];
    let found = false;
    while (actualEventIndex < actualEvents.length) {
      if (compareVeEvents(actualEvents[actualEventIndex], expectedEvent)) {
        found = true;
        matchStarted = true;
        actualEventIndex++;
        break;
      }
      if (matchStarted) {
        recordUnmatchedEvent(
            pendingEventExpectation, actualEvents[actualEventIndex], expectedEvent, matchedImpressions);
      }
      actualEventIndex++;
    }
    if (!found) {
      processMissingEvents(pendingEventExpectation, expectedEventIndex, matchedImpressions);
      if (!pendingEventExpectation.missingEvents?.length) {
        numMatchedEvents = actualEventIndex;
        pendingEventExpectation.success();
      }
      return;
    }
  }
  numMatchedEvents = actualEventIndex;
  pendingEventExpectation.success();
}

function getUnmatchedVeEvents(): string {
  console.error(numMatchedEvents);
  return formatVeEvents(veDebugEventsLog.slice(numMatchedEvents) as TestLogEntry[]);
}

// @ts-expect-error
globalThis.setVeDebugLoggingEnabled = setVeDebugLoggingEnabled;
// @ts-expect-error
globalThis.getUnmatchedVeEvents = getUnmatchedVeEvents;
// @ts-expect-error
globalThis.veDebugEventsLog = veDebugEventsLog;
// @ts-expect-error
globalThis.findVeDebugImpression = findVeDebugImpression;
// @ts-expect-error
globalThis.exportAdHocAnalysisLogForSql = exportAdHocAnalysisLogForSql;
// @ts-expect-error
globalThis.buildStateFlow = buildStateFlow;
// @ts-expect-error
globalThis.expectVeEvents = expectVeEvents;