/**
 * Copyright (c) Microsoft Corporation.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import type { EventEmitter } from 'events';
import fs from 'fs';
import path from 'path';
import { ManualPromise, ZipFile } from 'playwright-core/lib/utils';
import { yazl } from 'playwright-core/lib/zipBundle';
import { Readable } from 'stream';
import type { FullConfig, FullResult, Reporter } from '../../types/testReporter';
import type { BuiltInReporter, FullConfigInternal } from '../common/config';
import type { Suite } from '../common/test';
import { TeleReporterReceiver, type JsonEvent, type JsonProject, type JsonSuite } from '../isomorphic/teleReceiver';
import DotReporter from '../reporters/dot';
import EmptyReporter from '../reporters/empty';
import GitHubReporter from '../reporters/github';
import JSONReporter from '../reporters/json';
import JUnitReporter from '../reporters/junit';
import LineReporter from '../reporters/line';
import ListReporter from '../reporters/list';
import { loadReporter } from '../runner/loadUtils';
import HtmlReporter, { defaultReportFolder } from './html';
import { TeleReporterEmitter } from './teleEmitter';


type BlobReporterOptions = {
  configDir: string;
  outputDir?: string;
};

export class BlobReporter extends TeleReporterEmitter {
  private _messages: any[] = [];
  private _options: BlobReporterOptions;
  private _outputFile!: string;

  constructor(options: BlobReporterOptions) {
    super(message => this._messages.push(message));
    this._options = options;
  }

  override onBegin(config: FullConfig<{}, {}>, suite: Suite): void {
    super.onBegin(config, suite);
    this._computeOutputFileName(config);
  }

  override async onEnd(result: FullResult): Promise<void> {
    await super.onEnd(result);
    fs.mkdirSync(path.dirname(this._outputFile), { recursive: true });
    const lines = this._messages.map(m => JSON.stringify(m) + '\n');
    await zipReport(this._outputFile, lines);
  }

  private _computeOutputFileName(config: FullConfig) {
    const outputDir = this._resolveOutputDir();
    let shardSuffix = '';
    if (config.shard) {
      const paddedNumber = `${config.shard.current}`.padStart(`${config.shard.total}`.length, '0');
      shardSuffix = `-${paddedNumber}-of-${config.shard.total}`;
    }
    this._outputFile = path.join(outputDir, `report${shardSuffix}.zip`);
  }

  private _resolveOutputDir(): string {
    const { outputDir } = this._options;
    if (outputDir)
      return path.resolve(this._options.configDir, outputDir);
    return defaultReportFolder(this._options.configDir);
  }
}

export async function createMergedReport(config: FullConfigInternal, dir: string, reporterName?: string) {
  const shardFiles = await sortedShardFiles(dir);
  const events = await mergeEvents(dir, shardFiles);

  const defaultReporters: {[key in BuiltInReporter]: new(arg: any) => Reporter} = {
    dot: DotReporter,
    line: LineReporter,
    list: ListReporter,
    github: GitHubReporter,
    json: JSONReporter,
    junit: JUnitReporter,
    null: EmptyReporter,
    html: HtmlReporter,
    blob: BlobReporter,
  };
  reporterName ??= 'list';

  const arg = config.config.reporter.find(([reporter, arg]) => reporter === reporterName)?.[1];
  const options = {
    ...arg,
    configDir: process.cwd(),
    outputFolder: dir
  };

  let reporter: Reporter | undefined;
  if (reporterName in defaultReporters) {
    reporter = new defaultReporters[reporterName as keyof typeof defaultReporters](options);
  } else {
    const reporterConstructor = await loadReporter(config, reporterName);
    reporter = new reporterConstructor(options);
  }

  const receiver = new TeleReporterReceiver(path.sep, reporter);
  for (const event of events)
    await receiver.dispatch(event);
  console.log(`Done.`);
}

async function mergeEvents(dir: string, shardFiles: string[]) {
  const events: JsonEvent[] = [];
  const beginEvents: JsonEvent[] = [];
  const endEvents: JsonEvent[] = [];
  for (const file of shardFiles) {
    const zipFile = new ZipFile(path.join(dir, file));
    const entryNames = await zipFile.entries();
    const reportEntryName = entryNames.find(e => e.endsWith('.jsonl'));
    if (!reportEntryName)
      throw new Error(`Zip file ${file} does not contain a .jsonl file`);
    const reportJson = await zipFile.read(reportEntryName);
    const parsedEvents = reportJson.toString().split('\n').filter(line => line.length).map(line => JSON.parse(line)) as JsonEvent[];
    for (const event of parsedEvents) {
      // TODO: show remaining events?
      if (event.method === 'onError')
        throw new Error('Error in shard: ' + file);
      if (event.method === 'onBegin')
        beginEvents.push(event);
      else if (event.method === 'onEnd')
        endEvents.push(event);
      else
        events.push(event);
    }

  }
  return [mergeBeginEvents(beginEvents), ...events, mergeEndEvents(endEvents)];
}

function mergeBeginEvents(beginEvents: JsonEvent[]): JsonEvent {
  if (!beginEvents.length)
    throw new Error('No begin events found');
  const projects: JsonProject[] = [];
  let totalWorkers = 0;
  for (const event of beginEvents) {
    totalWorkers += event.params.config.workers;
    const shardProjects: JsonProject[] = event.params.projects;
    for (const shardProject of shardProjects) {
      const mergedProject = projects.find(p => p.id === shardProject.id);
      if (!mergedProject)
        projects.push(shardProject);
      else
        mergeJsonSuites(shardProject.suites, mergedProject);
    }
  }
  const config = {
    ...beginEvents[0].params.config,
    workers: totalWorkers,
    shard: undefined
  };
  return {
    method: 'onBegin',
    params: {
      config,
      projects,
    }
  };
}

function mergeJsonSuites(jsonSuites: JsonSuite[], parent: JsonSuite | JsonProject) {
  for (const jsonSuite of jsonSuites) {
    const existingSuite = parent.suites.find(s => s.title === jsonSuite.title);
    if (!existingSuite) {
      parent.suites.push(jsonSuite);
    } else {
      mergeJsonSuites(jsonSuite.suites, existingSuite);
      existingSuite.tests.push(...jsonSuite.tests);
    }
  }
}

function mergeEndEvents(endEvents: JsonEvent[]): JsonEvent {
  const result: FullResult = { status: 'passed' };
  for (const event of endEvents) {
    const shardResult: FullResult = event.params.result;
    if (shardResult.status === 'failed')
      result.status = 'failed';
    else if (shardResult.status === 'timedout' && result.status !== 'failed')
      result.status = 'timedout';
    else if (shardResult.status === 'interrupted' && result.status !== 'failed' && result.status !== 'timedout')
      result.status = 'interrupted';
  }
  return {
    method: 'onEnd',
    params: {
      result
    }
  };
}

async function sortedShardFiles(dir: string) {
  const files = await fs.promises.readdir(dir);
  return files.filter(file => file.endsWith('.zip')).sort();
}

async function zipReport(zipFileName: string, lines: string[]) {
  const zipFile = new yazl.ZipFile();
  const result = new ManualPromise<undefined>();
  (zipFile as any as EventEmitter).on('error', error => result.reject(error));
  // TODO: feed events on the fly.
  const content = Readable.from(lines);
  zipFile.addReadStream(content, 'report.jsonl');
  zipFile.end();
  zipFile.outputStream.pipe(fs.createWriteStream(zipFileName)).on('close', () => {
    result.resolve(undefined);
  });
  await result;
}