// Integration tests related utils

'use strict';

const path = require('path');
const fse = require('fs-extra');
const spawn = require('child-process-ext/spawn');
const nodeFetch = require('node-fetch');
const log = require('log').get('serverless:test');
const logFetch = require('log').get('fetch');
const wait = require('timers-ext/promise/sleep');
const resolveAwsEnv = require('@serverless/test/resolve-aws-env');
const { load: loadYaml } = require('js-yaml');

const serverlessExec = require('../serverlessBinary');

const env = resolveAwsEnv();
env.SLS_DEBUG = '1';

async function resolveServiceName(cwd) {
  const configContent = await (async () => {
    try {
      return await fse.readFile(path.join(cwd, 'serverless.yml'));
    } catch (error) {
      if (error.code === 'ENOENT') return null;
      throw error;
    }
  })();
  if (!configContent) return null;
  const configObject = (() => {
    try {
      return loadYaml(configContent);
    } catch (error) {
      return null;
    }
  })();
  if (!configObject) return null;
  return configObject.service;
}

async function deployService(cwd) {
  log.notice('deploy %s (at %s)', (await resolveServiceName(cwd)) || '[unknown]', cwd);
  return spawn(serverlessExec, ['deploy'], { cwd, env });
}

async function removeService(cwd) {
  log.notice('remove %s (at %s)', (await resolveServiceName(cwd)) || '[unknown]', cwd);
  return spawn(serverlessExec, ['remove'], { cwd, env });
}

async function getFunctionLogs(cwd, functionName) {
  let logs;
  try {
    ({ stdoutBuffer: logs } = await spawn(
      serverlessExec,
      ['logs', '--function', functionName, '--noGreeting', 'true'],
      {
        cwd,
        env,
      }
    ));
  } catch (_) {
    // Attempting to read logs before first invocation will will result in a "No existing streams for the function" error
    return null;
  }
  return String(logs);
}

const defaultTimeout = 60000;

async function waitForFunctionLogs(cwd, functionName, startMarker, endMarker, options = {}) {
  const timeout = options.timeout || defaultTimeout;
  const startTime = Date.now();
  await wait(2000);
  const logs = await getFunctionLogs(cwd, functionName);
  if (logs && logs.includes(startMarker) && logs.includes(endMarker)) return logs;
  const timeSpan = Date.now() - startTime;
  if (timeSpan > timeout) throw new Error('Cannot find function logs');
  return waitForFunctionLogs(cwd, functionName, startMarker, endMarker, {
    timeout: timeout - timeSpan,
  });
}

let lastRequestId = 0;
async function fetch(url, options) {
  const requestId = ++lastRequestId;
  logFetch.debug('[%d] %s %o', requestId, url, options);

  let response;
  try {
    response = await nodeFetch(url, options);
  } catch (error) {
    logFetch.error('[%d] request error: %o', requestId, error);
    throw error;
  }

  logFetch.debug('[%d] %d %j', requestId, response.status, response.headers.raw());
  /* eslint-enable */
  response
    .clone()
    .buffer()
    .then(
      buffer => logFetch.debug('[%d] %s', requestId, String(buffer)),
      error => logFetch.error('[%d] response resolution error: %o', requestId, error)
    );
  return response;
}

function getMarkers(functionName) {
  return {
    start: `--- START ${functionName} ---`,
    end: `--- END ${functionName} ---`,
  };
}

module.exports = {
  deployService,
  env,
  fetch,
  removeService,
  waitForFunctionLogs,
  getMarkers,
};