/**
 * 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 fs from 'fs';
import type EventEmitter from 'events';
import type { ClientSideCallMetadata, SerializedError, StackFrame } from '@protocol/channels';
import type { SerializedClientSideCallMetadata, SerializedStack, SerializedStackFrame } from './isomorphic/traceUtils';
import { yazl, yauzl } from '../zipBundle';
import { ManualPromise } from './manualPromise';
import type { AfterActionTraceEvent, BeforeActionTraceEvent, TraceEvent } from '@trace/trace';
import { calculateSha1 } from './crypto';
import { monotonicTime } from './time';

export function serializeClientSideCallMetadata(metadatas: ClientSideCallMetadata[]): SerializedClientSideCallMetadata {
  const fileNames = new Map<string, number>();
  const stacks: SerializedStack[] = [];
  for (const m of metadatas) {
    if (!m.stack || !m.stack.length)
      continue;
    const stack: SerializedStackFrame[] = [];
    for (const frame of m.stack) {
      let ordinal = fileNames.get(frame.file);
      if (typeof ordinal !== 'number') {
        ordinal = fileNames.size;
        fileNames.set(frame.file, ordinal);
      }
      const stackFrame: SerializedStackFrame = [ordinal, frame.line || 0, frame.column || 0, frame.function || ''];
      stack.push(stackFrame);
    }
    stacks.push([m.id, stack]);
  }
  return { files: [...fileNames.keys()], stacks };
}

export async function mergeTraceFiles(fileName: string, temporaryTraceFiles: string[]) {
  if (temporaryTraceFiles.length === 1) {
    await fs.promises.rename(temporaryTraceFiles[0], fileName);
    return;
  }

  const mergePromise = new ManualPromise();
  const zipFile = new yazl.ZipFile();
  const entryNames = new Set<string>();
  (zipFile as any as EventEmitter).on('error', error => mergePromise.reject(error));

  for (let i = 0; i < temporaryTraceFiles.length; ++i) {
    const tempFile = temporaryTraceFiles[i];
    const promise = new ManualPromise<void>();
    yauzl.open(tempFile, (err, inZipFile) => {
      if (err) {
        promise.reject(err);
        return;
      }
      let pendingEntries = inZipFile.entryCount;
      inZipFile.on('entry', entry => {
        let entryName = entry.fileName;
        if (entry.fileName.match(/[\d-]*trace./))
          entryName = i + '-' + entry.fileName;
        inZipFile.openReadStream(entry, (err, readStream) => {
          if (err) {
            promise.reject(err);
            return;
          }
          if (!entryNames.has(entryName)) {
            entryNames.add(entryName);
            zipFile.addReadStream(readStream!, entryName);
          }
          if (--pendingEntries === 0)
            promise.resolve();
        });
      });
    });
    await promise;
  }

  zipFile.end(undefined, () => {
    zipFile.outputStream.pipe(fs.createWriteStream(fileName)).on('close', () => {
      Promise.all(temporaryTraceFiles.map(tempFile => fs.promises.unlink(tempFile))).then(() => {
        mergePromise.resolve();
      });
    }).on('error', error => mergePromise.reject(error));
  });
  await mergePromise;
}

export async function saveTraceFile(fileName: string, traceEvents: TraceEvent[], saveSources: boolean) {
  const zipFile = new yazl.ZipFile();

  if (saveSources) {
    const sourceFiles = new Set<string>();
    for (const event of traceEvents) {
      if (event.type === 'before') {
        for (const frame of event.stack || [])
          sourceFiles.add(frame.file);
      }
    }
    for (const sourceFile of sourceFiles) {
      await fs.promises.readFile(sourceFile, 'utf8').then(source => {
        zipFile.addBuffer(Buffer.from(source), 'resources/src@' + calculateSha1(sourceFile) + '.txt');
      }).catch(() => {});
    }
  }

  const sha1s = new Set<string>();
  for (const event of traceEvents.filter(e => e.type === 'after') as AfterActionTraceEvent[]) {
    for (const attachment of (event.attachments || [])) {
      let contentPromise: Promise<Buffer | undefined> | undefined;
      if (attachment.path)
        contentPromise = fs.promises.readFile(attachment.path).catch(() => undefined);
      else if (attachment.base64)
        contentPromise = Promise.resolve(Buffer.from(attachment.base64, 'base64'));

      const content = await contentPromise;
      if (content === undefined)
        continue;

      const sha1 = calculateSha1(content);
      attachment.sha1 = sha1;
      delete attachment.path;
      delete attachment.base64;
      if (sha1s.has(sha1))
        continue;
      sha1s.add(sha1);
      zipFile.addBuffer(content, 'resources/' + sha1);
    }
  }

  const traceContent = Buffer.from(traceEvents.map(e => JSON.stringify(e)).join('\n'));
  zipFile.addBuffer(traceContent, 'trace.trace');

  await new Promise(f => {
    zipFile.end(undefined, () => {
      zipFile.outputStream.pipe(fs.createWriteStream(fileName)).on('close', f);
    });
  });
}

export function createBeforeActionTraceEventForStep(callId: string, parentId: string | undefined, apiName: string, params: Record<string, any> | undefined, wallTime: number, stack: StackFrame[]): BeforeActionTraceEvent {
  return {
    type: 'before',
    callId,
    parentId,
    wallTime,
    startTime: monotonicTime(),
    class: 'Test',
    method: 'step',
    apiName,
    params: Object.fromEntries(Object.entries(params || {}).map(([name, value]) => [name, generatePreview(value)])),
    stack,
  };
}

export function createAfterActionTraceEventForStep(callId: string, attachments: AfterActionTraceEvent['attachments'], error?: SerializedError['error']): AfterActionTraceEvent {
  return {
    type: 'after',
    callId,
    endTime: monotonicTime(),
    log: [],
    attachments,
    error,
  };
}

function generatePreview(value: any, visited = new Set<any>()): string {
  if (visited.has(value))
    return '';
  visited.add(value);
  if (typeof value === 'string')
    return value;
  if (typeof value === 'number')
    return value.toString();
  if (typeof value === 'boolean')
    return value.toString();
  if (value === null)
    return 'null';
  if (value === undefined)
    return 'undefined';
  if (Array.isArray(value))
    return '[' + value.map(v => generatePreview(v, visited)).join(', ') + ']';
  if (typeof value === 'object')
    return 'Object';
  return String(value);
}