const
  Schema = require('mongoose').Schema,
  Job = require('./job'),
  User = require('./user'),
  UserTypes = require('../helpers/constants').UserTypes,
  Location = require('./location'),
  Location_Cache = require('./location_cache'),
  mongoUtil = require('../helpers/mongo');

const schema = new Schema({
  vehicleType: { type: Number, required: false, default: 0 },    //0: fixed swing, 1: helicopter
  unitId: {
    type: String, trim: true, required: false, maxlength: 15,
    index: {
      unique: true,
      partialFilterExpression: { unitId: { $type: 'string' } }
    },
    set: v => (v === '' ? null : v)
  },
  model: { type: String, required: false },
  desc: { type: String, required: false },
  color: { type: String, default: 'yellow' },
  // Whether the vehicle is tracking enabled.
  tracking: { type: Boolean, default: false },
  trackonDate: { type: Date, default: null }
}, { strictQuery: false });

async function updateRelatedJobs(session) {
  session && (session.startTransaction(mongoUtil.getTranOps()));
  try {
    await Job.updateMany({ vehicle: this._id }, { $set: { vehicle: null } }).session(session);
  } catch (error) {
    session && (session.abortTransaction());
    throw error;
  }
  await mongoUtil.commitWithRetry(session);
}

async function deleteTrackingData() {
  if (this.unitId) {
    await Location.deleteMany({ unitId: this.unitId });
    await Location_Cache.deleteMany({ unitId: this.unitId });
  }
}

/**
 * Remove the Vehicle with all related data.
 * @param {ClientSession} ses the transactional db session. If ses is null, create a session and end when done.
 * @param {boolean} markDeletedOnly Determine whether to just mark the item as deleted only. Default is true.
 */
schema.methods.removeFull = async function (ses = null, markDeletedOnly = true) {
  const endSesDone = !ses;
  const session = ses || await this.db.startSession({ readPreference: { mode: "primary" } });
  try {
    // 1. Mark this application and all its files as deleted - use transaction
    await mongoUtil.runTransactionWithRetry(this.markAsDeleted.bind(this), session);
    if (!markDeletedOnly) {
      // 2. Set null for related jobs
      await mongoUtil.runTransactionWithRetry(updateRelatedJobs.bind(this), session);

      // 3. Clear tracking data
      await deleteTrackingData.call(this);

      // 4. Delete the application
      await mongoUtil.runTransactionWithRetry(this.deleteMarked.bind(this), session);
    }
  } catch (error) {
    throw error;
  } finally {
    if (session && endSesDone) await session.endSession();
  }
}

module.exports = User.discriminator(UserTypes.DEVICE, schema, { clone: false });