let ThreadManager
const { db, ObjectId } = require('../../mongodb')
const logger = require('@overleaf/logger')
const metrics = require('@overleaf/metrics')

const GLOBAL_THREAD = 'GLOBAL'

function findOrCreateThread(projectId, threadId, callback) {
  let query, update
  projectId = ObjectId(projectId.toString())
  if (threadId !== GLOBAL_THREAD) {
    threadId = ObjectId(threadId.toString())
  }

  if (threadId === GLOBAL_THREAD) {
    query = {
      project_id: projectId,
      thread_id: { $exists: false },
    }
    update = {
      project_id: projectId,
    }
  } else {
    query = {
      project_id: projectId,
      thread_id: threadId,
    }
    update = {
      project_id: projectId,
      thread_id: threadId,
    }
  }

  db.rooms.findOneAndUpdate(
    query,
    { $set: update },
    { upsert: true, returnDocument: 'after' },
    function (error, result) {
      if (error) {
        return callback(error)
      }
      callback(null, result.value)
    }
  )
}

function findAllThreadRooms(projectId, callback) {
  db.rooms
    .find(
      {
        project_id: ObjectId(projectId.toString()),
        thread_id: { $exists: true },
      },
      {
        thread_id: 1,
        resolved: 1,
      }
    )
    .toArray(callback)
}

function resolveThread(projectId, threadId, userId, callback) {
  db.rooms.updateOne(
    {
      project_id: ObjectId(projectId.toString()),
      thread_id: ObjectId(threadId.toString()),
    },
    {
      $set: {
        resolved: {
          user_id: userId,
          ts: new Date(),
        },
      },
    },
    callback
  )
}

function reopenThread(projectId, threadId, callback) {
  db.rooms.updateOne(
    {
      project_id: ObjectId(projectId.toString()),
      thread_id: ObjectId(threadId.toString()),
    },
    {
      $unset: {
        resolved: true,
      },
    }
  )
}

function deleteThread(projectId, threadId, callback) {
  findOrCreateThread(projectId, threadId, function (error, room) {
    if (error) {
      return callback(error)
    }
    db.rooms.deleteOne(
      {
        _id: room._id,
      },
      function (error) {
        if (error) {
          return callback(error)
        }
        callback(null, room._id)
      }
    )
  })
}

module.exports = ThreadManager = {
  GLOBAL_THREAD,
  findOrCreateThread,
  findAllThreadRooms,
  resolveThread,
  reopenThread,
  deleteThread,
}
;[
  'findOrCreateThread',
  'findAllThreadRooms',
  'resolveThread',
  'reopenThread',
  'deleteThread',
].map(method =>
  metrics.timeAsyncMethod(ThreadManager, method, 'mongo.ThreadManager', logger)
)