/* eslint-disable
    camelcase,
    handle-callback-err,
    no-return-assign,
    no-unused-vars,
*/
// TODO: This file was created by bulk-decaffeinate.
// Fix any style issues and re-enable lint.
/*
 * decaffeinate suggestions:
 * DS101: Remove unnecessary use of Array.from
 * DS102: Remove unnecessary code created because of implicit returns
 * DS103: Rewrite code to no longer use __guard__
 * DS205: Consider reworking code to avoid use of IIFEs
 * DS207: Consider shorter variations of null checks
 * Full docs: https://github.com/decaffeinate/decaffeinate/blob/master/docs/suggestions.md
 */
let DockerRunner, oneHour
const Settings = require('settings-sharelatex')
const logger = require('logger-sharelatex')
const Docker = require('dockerode')
const dockerode = new Docker()
const crypto = require('crypto')
const async = require('async')
const LockManager = require('./DockerLockManager')
const fs = require('fs')
const Path = require('path')
const _ = require('lodash')

logger.info('using docker runner')

const usingSiblingContainers = () =>
  __guard__(
    Settings != null ? Settings.path : undefined,
    x => x.sandboxedCompilesHostDir
  ) != null

let containerMonitorTimeout
let containerMonitorInterval

module.exports = DockerRunner = {
  ERR_NOT_DIRECTORY: new Error('not a directory'),
  ERR_TERMINATED: new Error('terminated'),
  ERR_EXITED: new Error('exited'),
  ERR_TIMED_OUT: new Error('container timed out'),

  run(
    project_id,
    command,
    directory,
    image,
    timeout,
    environment,
    compileGroup,
    callback
  ) {
    let name
    if (callback == null) {
      callback = function(error, output) {}
    }
    if (usingSiblingContainers()) {
      const _newPath = Settings.path.sandboxedCompilesHostDir
      logger.log(
        { path: _newPath },
        'altering bind path for sibling containers'
      )
      // Server Pro, example:
      //   '/var/lib/sharelatex/data/compiles/<project-id>'
      //   ... becomes ...
      //   '/opt/sharelatex_data/data/compiles/<project-id>'
      directory = Path.join(
        Settings.path.sandboxedCompilesHostDir,
        Path.basename(directory)
      )
    }

    const volumes = {}
    volumes[directory] = '/compile'

    command = Array.from(command).map(arg =>
      __guardMethod__(arg.toString(), 'replace', o =>
        o.replace('$COMPILE_DIR', '/compile')
      )
    )
    if (image == null) {
      ;({ image } = Settings.clsi.docker)
    }

    if (
      Settings.clsi.docker.allowedImages &&
      !Settings.clsi.docker.allowedImages.includes(image)
    ) {
      return callback(new Error('image not allowed'))
    }

    if (Settings.texliveImageNameOveride != null) {
      const img = image.split('/')
      image = `${Settings.texliveImageNameOveride}/${img[2]}`
    }

    const options = DockerRunner._getContainerOptions(
      command,
      image,
      volumes,
      timeout,
      environment,
      compileGroup
    )
    const fingerprint = DockerRunner._fingerprintContainer(options)
    options.name = name = `project-${project_id}-${fingerprint}`

    // logOptions = _.clone(options)
    // logOptions?.HostConfig?.SecurityOpt = "secomp used, removed in logging"
    logger.log({ project_id }, 'running docker container')
    DockerRunner._runAndWaitForContainer(options, volumes, timeout, function(
      error,
      output
    ) {
      if (error && error.statusCode === 500) {
        logger.log(
          { err: error, project_id },
          'error running container so destroying and retrying'
        )
        return DockerRunner.destroyContainer(name, null, true, function(error) {
          if (error != null) {
            return callback(error)
          }
          return DockerRunner._runAndWaitForContainer(
            options,
            volumes,
            timeout,
            callback
          )
        })
      } else {
        return callback(error, output)
      }
    })

    return name
  }, // pass back the container name to allow it to be killed

  kill(container_id, callback) {
    if (callback == null) {
      callback = function(error) {}
    }
    logger.log({ container_id }, 'sending kill signal to container')
    const container = dockerode.getContainer(container_id)
    return container.kill(function(error) {
      if (
        error != null &&
        __guardMethod__(error != null ? error.message : undefined, 'match', o =>
          o.match(/Cannot kill container .* is not running/)
        )
      ) {
        logger.warn(
          { err: error, container_id },
          'container not running, continuing'
        )
        error = null
      }
      if (error != null) {
        logger.error({ err: error, container_id }, 'error killing container')
        return callback(error)
      } else {
        return callback()
      }
    })
  },

  _runAndWaitForContainer(options, volumes, timeout, _callback) {
    if (_callback == null) {
      _callback = function(error, output) {}
    }
    const callback = function(...args) {
      _callback(...Array.from(args || []))
      // Only call the callback once
      return (_callback = function() {})
    }

    const { name } = options

    let streamEnded = false
    let containerReturned = false
    let output = {}

    const callbackIfFinished = function() {
      if (streamEnded && containerReturned) {
        return callback(null, output)
      }
    }

    const attachStreamHandler = function(error, _output) {
      if (error != null) {
        return callback(error)
      }
      output = _output
      streamEnded = true
      return callbackIfFinished()
    }

    return DockerRunner.startContainer(
      options,
      volumes,
      attachStreamHandler,
      function(error, containerId) {
        if (error != null) {
          return callback(error)
        }

        return DockerRunner.waitForContainer(name, timeout, function(
          error,
          exitCode
        ) {
          let err
          if (error != null) {
            return callback(error)
          }
          if (exitCode === 137) {
            // exit status from kill -9
            err = DockerRunner.ERR_TERMINATED
            err.terminated = true
            return callback(err)
          }
          if (exitCode === 1) {
            // exit status from chktex
            err = DockerRunner.ERR_EXITED
            err.code = exitCode
            return callback(err)
          }
          containerReturned = true
          __guard__(
            options != null ? options.HostConfig : undefined,
            x => (x.SecurityOpt = null)
          ) // small log line
          logger.log({ err, exitCode, options }, 'docker container has exited')
          return callbackIfFinished()
        })
      }
    )
  },

  _getContainerOptions(
    command,
    image,
    volumes,
    timeout,
    environment,
    compileGroup
  ) {
    let m, year
    let key, value, hostVol, dockerVol
    const timeoutInSeconds = timeout / 1000

    const dockerVolumes = {}
    for (hostVol in volumes) {
      dockerVol = volumes[hostVol]
      dockerVolumes[dockerVol] = {}

      if (volumes[hostVol].slice(-3).indexOf(':r') === -1) {
        volumes[hostVol] = `${dockerVol}:rw`
      }
    }

    // merge settings and environment parameter
    const env = {}
    for (const src of [Settings.clsi.docker.env, environment || {}]) {
      for (key in src) {
        value = src[key]
        env[key] = value
      }
    }
    // set the path based on the image year
    if ((m = image.match(/:([0-9]+)\.[0-9]+/))) {
      year = m[1]
    } else {
      year = '2014'
    }
    env.PATH = `/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/local/texlive/${year}/bin/x86_64-linux/`
    const options = {
      Cmd: command,
      Image: image,
      Volumes: dockerVolumes,
      WorkingDir: '/compile',
      NetworkDisabled: true,
      Memory: 1024 * 1024 * 1024 * 1024, // 1 Gb
      User: Settings.clsi.docker.user,
      Env: (() => {
        const result = []
        for (key in env) {
          value = env[key]
          result.push(`${key}=${value}`)
        }
        return result
      })(), // convert the environment hash to an array
      HostConfig: {
        Binds: (() => {
          const result1 = []
          for (hostVol in volumes) {
            dockerVol = volumes[hostVol]
            result1.push(`${hostVol}:${dockerVol}`)
          }
          return result1
        })(),
        LogConfig: { Type: 'none', Config: {} },
        Ulimits: [
          {
            Name: 'cpu',
            Soft: timeoutInSeconds + 5,
            Hard: timeoutInSeconds + 10
          }
        ],
        CapDrop: 'ALL',
        SecurityOpt: ['no-new-privileges']
      }
    }

    if (
      (Settings.path != null ? Settings.path.synctexBinHostPath : undefined) !=
      null
    ) {
      options.HostConfig.Binds.push(
        `${Settings.path.synctexBinHostPath}:/opt/synctex:ro`
      )
    }

    if (Settings.clsi.docker.seccomp_profile != null) {
      options.HostConfig.SecurityOpt.push(
        `seccomp=${Settings.clsi.docker.seccomp_profile}`
      )
    }

    if (Settings.clsi.docker.runtime) {
      options.HostConfig.Runtime = Settings.clsi.docker.runtime
    }

    if (Settings.clsi.docker.Readonly) {
      options.HostConfig.ReadonlyRootfs = true
      options.HostConfig.Tmpfs = { '/tmp': 'rw,noexec,nosuid,size=65536k' }
    }

    // Allow per-compile group overriding of individual settings
    if (
      Settings.clsi.docker.compileGroupConfig &&
      Settings.clsi.docker.compileGroupConfig[compileGroup]
    ) {
      const override = Settings.clsi.docker.compileGroupConfig[compileGroup]
      let key
      for (key in override) {
        _.set(options, key, override[key])
      }
    }

    return options
  },

  _fingerprintContainer(containerOptions) {
    // Yay, Hashing!
    const json = JSON.stringify(containerOptions)
    return crypto
      .createHash('md5')
      .update(json)
      .digest('hex')
  },

  startContainer(options, volumes, attachStreamHandler, callback) {
    return LockManager.runWithLock(
      options.name,
      releaseLock =>
        // Check that volumes exist before starting the container.
        // When a container is started with volume pointing to a
        // non-existent directory then docker creates the directory but
        // with root ownership.
        DockerRunner._checkVolumes(options, volumes, function(err) {
          if (err != null) {
            return releaseLock(err)
          }
          return DockerRunner._startContainer(
            options,
            volumes,
            attachStreamHandler,
            releaseLock
          )
        }),

      callback
    )
  },

  // Check that volumes exist and are directories
  _checkVolumes(options, volumes, callback) {
    if (callback == null) {
      callback = function(error, containerName) {}
    }
    if (usingSiblingContainers()) {
      // Server Pro, with sibling-containers active, skip checks
      return callback(null)
    }

    const checkVolume = (path, cb) =>
      fs.stat(path, function(err, stats) {
        if (err != null) {
          return cb(err)
        }
        if (!(stats != null ? stats.isDirectory() : undefined)) {
          return cb(DockerRunner.ERR_NOT_DIRECTORY)
        }
        return cb()
      })
    const jobs = []
    for (const vol in volumes) {
      ;(vol => jobs.push(cb => checkVolume(vol, cb)))(vol)
    }
    return async.series(jobs, callback)
  },

  _startContainer(options, volumes, attachStreamHandler, callback) {
    if (callback == null) {
      callback = function(error, output) {}
    }
    callback = _.once(callback)
    const { name } = options

    logger.log({ container_name: name }, 'starting container')
    const container = dockerode.getContainer(name)

    const createAndStartContainer = () =>
      dockerode.createContainer(options, function(error, container) {
        if (error != null) {
          return callback(error)
        }
        return startExistingContainer()
      })
    var startExistingContainer = () =>
      DockerRunner.attachToContainer(
        options.name,
        attachStreamHandler,
        function(error) {
          if (error != null) {
            return callback(error)
          }
          return container.start(function(error) {
            if (
              error != null &&
              (error != null ? error.statusCode : undefined) !== 304
            ) {
              // already running
              return callback(error)
            } else {
              return callback()
            }
          })
        }
      )
    return container.inspect(function(error, stats) {
      if ((error != null ? error.statusCode : undefined) === 404) {
        return createAndStartContainer()
      } else if (error != null) {
        logger.err(
          { container_name: name, error },
          'unable to inspect container to start'
        )
        return callback(error)
      } else {
        return startExistingContainer()
      }
    })
  },

  attachToContainer(containerId, attachStreamHandler, attachStartCallback) {
    const container = dockerode.getContainer(containerId)
    return container.attach({ stdout: 1, stderr: 1, stream: 1 }, function(
      error,
      stream
    ) {
      if (error != null) {
        logger.error(
          { err: error, container_id: containerId },
          'error attaching to container'
        )
        return attachStartCallback(error)
      } else {
        attachStartCallback()
      }

      logger.log({ container_id: containerId }, 'attached to container')

      const MAX_OUTPUT = 1024 * 1024 // limit output to 1MB
      const createStringOutputStream = function(name) {
        return {
          data: '',
          overflowed: false,
          write(data) {
            if (this.overflowed) {
              return
            }
            if (this.data.length < MAX_OUTPUT) {
              return (this.data += data)
            } else {
              logger.error(
                {
                  container_id: containerId,
                  length: this.data.length,
                  maxLen: MAX_OUTPUT
                },
                `${name} exceeds max size`
              )
              this.data += `(...truncated at ${MAX_OUTPUT} chars...)`
              return (this.overflowed = true)
            }
          }
          // kill container if too much output
          // docker.containers.kill(containerId, () ->)
        }
      }

      const stdout = createStringOutputStream('stdout')
      const stderr = createStringOutputStream('stderr')

      container.modem.demuxStream(stream, stdout, stderr)

      stream.on('error', err =>
        logger.error(
          { err, container_id: containerId },
          'error reading from container stream'
        )
      )

      return stream.on('end', () =>
        attachStreamHandler(null, { stdout: stdout.data, stderr: stderr.data })
      )
    })
  },

  waitForContainer(containerId, timeout, _callback) {
    if (_callback == null) {
      _callback = function(error, exitCode) {}
    }
    const callback = function(...args) {
      _callback(...Array.from(args || []))
      // Only call the callback once
      return (_callback = function() {})
    }

    const container = dockerode.getContainer(containerId)

    let timedOut = false
    const timeoutId = setTimeout(function() {
      timedOut = true
      logger.log(
        { container_id: containerId },
        'timeout reached, killing container'
      )
      return container.kill(function() {})
    }, timeout)

    logger.log({ container_id: containerId }, 'waiting for docker container')
    return container.wait(function(error, res) {
      if (error != null) {
        clearTimeout(timeoutId)
        logger.error(
          { err: error, container_id: containerId },
          'error waiting for container'
        )
        return callback(error)
      }
      if (timedOut) {
        logger.log({ containerId }, 'docker container timed out')
        error = DockerRunner.ERR_TIMED_OUT
        error.timedout = true
        return callback(error)
      } else {
        clearTimeout(timeoutId)
        logger.log(
          { container_id: containerId, exitCode: res.StatusCode },
          'docker container returned'
        )
        return callback(null, res.StatusCode)
      }
    })
  },

  destroyContainer(containerName, containerId, shouldForce, callback) {
    // We want the containerName for the lock and, ideally, the
    // containerId to delete.  There is a bug in the docker.io module
    // where if you delete by name and there is an error, it throws an
    // async exception, but if you delete by id it just does a normal
    // error callback. We fall back to deleting by name if no id is
    // supplied.
    if (callback == null) {
      callback = function(error) {}
    }
    return LockManager.runWithLock(
      containerName,
      releaseLock =>
        DockerRunner._destroyContainer(
          containerId || containerName,
          shouldForce,
          releaseLock
        ),
      callback
    )
  },

  _destroyContainer(containerId, shouldForce, callback) {
    if (callback == null) {
      callback = function(error) {}
    }
    logger.log({ container_id: containerId }, 'destroying docker container')
    const container = dockerode.getContainer(containerId)
    return container.remove({ force: shouldForce === true }, function(error) {
      if (
        error != null &&
        (error != null ? error.statusCode : undefined) === 404
      ) {
        logger.warn(
          { err: error, container_id: containerId },
          'container not found, continuing'
        )
        error = null
      }
      if (error != null) {
        logger.error(
          { err: error, container_id: containerId },
          'error destroying container'
        )
      } else {
        logger.log({ container_id: containerId }, 'destroyed container')
      }
      return callback(error)
    })
  },

  // handle expiry of docker containers

  MAX_CONTAINER_AGE:
    Settings.clsi.docker.maxContainerAge || (oneHour = 60 * 60 * 1000),

  examineOldContainer(container, callback) {
    if (callback == null) {
      callback = function(error, name, id, ttl) {}
    }
    const name =
      container.Name ||
      (container.Names != null ? container.Names[0] : undefined)
    const created = container.Created * 1000 // creation time is returned in seconds
    const now = Date.now()
    const age = now - created
    const maxAge = DockerRunner.MAX_CONTAINER_AGE
    const ttl = maxAge - age
    logger.log(
      { containerName: name, created, now, age, maxAge, ttl },
      'checking whether to destroy container'
    )
    return callback(null, name, container.Id, ttl)
  },

  destroyOldContainers(callback) {
    if (callback == null) {
      callback = function(error) {}
    }
    return dockerode.listContainers({ all: true }, function(error, containers) {
      if (error != null) {
        return callback(error)
      }
      const jobs = []
      for (const container of Array.from(containers || [])) {
        ;(container =>
          DockerRunner.examineOldContainer(container, function(
            err,
            name,
            id,
            ttl
          ) {
            if (name.slice(0, 9) === '/project-' && ttl <= 0) {
              // strip the / prefix
              // the LockManager uses the plain container name
              name = name.slice(1)
              return jobs.push(cb =>
                DockerRunner.destroyContainer(name, id, false, () => cb())
              )
            }
          }))(container)
      }
      // Ignore errors because some containers get stuck but
      // will be destroyed next time
      return async.series(jobs, callback)
    })
  },

  startContainerMonitor() {
    logger.log(
      { maxAge: DockerRunner.MAX_CONTAINER_AGE },
      'starting container expiry'
    )

    // guarantee only one monitor is running
    DockerRunner.stopContainerMonitor()

    // randomise the start time
    const randomDelay = Math.floor(Math.random() * 5 * 60 * 1000)
    containerMonitorTimeout = setTimeout(() => {
      containerMonitorInterval = setInterval(
        () => DockerRunner.destroyOldContainers(),
        (oneHour = 60 * 60 * 1000)
      )
    }, randomDelay)
  },

  stopContainerMonitor() {
    if (containerMonitorTimeout) {
      clearTimeout(containerMonitorTimeout)
      containerMonitorTimeout = undefined
    }
    if (containerMonitorInterval) {
      clearInterval(containerMonitorTimeout)
      containerMonitorTimeout = undefined
    }
  }
}

DockerRunner.startContainerMonitor()

function __guard__(value, transform) {
  return typeof value !== 'undefined' && value !== null
    ? transform(value)
    : undefined
}
function __guardMethod__(obj, methodName, transform) {
  if (
    typeof obj !== 'undefined' &&
    obj !== null &&
    typeof obj[methodName] === 'function'
  ) {
    return transform(obj, methodName)
  } else {
    return undefined
  }
}