const sequelizeInit = require('./sequelize.js')
const sequelize = sequelizeInit.initSequelize()

const User = require('./models/userModel.js')
const Role = require('./models/roleModel.js')
const Course = require('./models/courseModel.js')
const Queue = require('./models/queueModel.js')

const fs = require('fs')

var Users
var Roles
var StudentStatistics
var CourseStatistics
var Courses
var Queues

// contains sequelize models of the queues.
// Dynamic length depending on how many queues (=#courses) we have
const queueModels = []

const courses = []
const users = []
const roles = []
const queues = []

// creating sequelize models
exports.initDatabase = () => {
  // sequelizeInit.autoSequelize()
  initConstants()
}
function initConstants () {
  Users = sequelize.import('./seq_models/users1.js')
  Roles = sequelize.import('./seq_models/roles1.js')
  StudentStatistics = sequelize.import('./seq_models/studentStatistics1.js')
  CourseStatistics = sequelize.import('./seq_models/courseStatistics1.js')
  Courses = sequelize.import('./seq_models/courses1.js')
  Queues = sequelize.import('./seq_models/queues1.js')

  linkModels()
  fillCache()

  // initQueueModels()
}

// creates sequelize models for the queues
function initQueueModels () {
  fs.readdir('./seq_models', function (err, items) {
    if (err) {
      console.error(err)
      throw err
    } else {
      for (let file of items) {
        if (file.substring(0, 2) === file.substring(0, 2).toUpperCase()) {
          let seqConstant = sequelize.import('./seq_models/' + file)
          queueModels.push({ ID: file.substring(0, file.length - 3), model: seqConstant })
        }
      }
      linkModels()
      fillCache()
    }
  })
}

function linkModels () {
  Queues.belongsTo(Users, { foreignKey: 'student' })
  Queues.belongsTo(Courses, { foreignKey: 'courseID' })
  console.log('linked')

  // for (let i = 0; i < queueModels.length; i++) {
  //   queueModels[i].model.belongsTo(Users, { foreignKey: 'student' })
  // }
}

function fillCache () {
  fillUsers()
  fillRoles()
  fillQueuesAndCourses()
}

// fill User fillCache
// works
function fillUsers () {
  Users.findAll().then(res => {
    for (let user of res) {
      // console.log(user.ID, user.name, user.email, user.password)
      users.push(new User(
        {
          ID: user.ID,
          name: user.name,
          email: user.email,
          password: user.password
        }
      )
      )
      // console.log(users)
    }
  })
}

// fill roles cache
// works
function fillRoles () {
  Roles.findAll().then(res => {
    for (let role of res) {
      roles.push(new Role(
        {
          ID: role.ID,
          courseID: role.courseID,
          role: role.role
        })
      )
    }
  })
}

function fillQueuesAndCourses () {
  Queues.findAll({
    include: [
      { model: Users },
      { model: Courses }
    ],
    attributes: ['users1.name', 'student', 'task', 'location', 'comment', 'queueNo', 'enterTime', 'courses1.name', 'courses1.ID']
  }).then(res => {
    for (let queue of res) {
      // console.log('------this queue query',queue.student, queue.users1.name, queue.task, queue.location, queue.queueNo, queue.enterTime, queue.courses1.name, queue.courses1.ID)
      if (courses.some(e => e.ID === queue.courses1.ID)) {

      } else {
        courses.push(new Course({
          ID: queue.courses1.ID,
          name: queue.courses1.name
        }))

        console.log(courses)
      }

      // adds students in queue to given course
      var queueItem = {
        studentID: queue.student,
        studentName: queue.users1.name,
        task: queue.task,
        location: queue.location,
        queueNo: queue.queueNo, // kanske inte behövs
        enterTime: queue.enterTime
      }

      if (queues.some(e => e.ID === queue.courses1.ID)) {
        appendToQueue(queue.courses1.ID, queueItem)
      } else {
        console.log('elseQueue')
        queues.push(new Queue({
          ID: queue.courses1.ID,
          name: queue.courses1.name,
          queue: [queueItem]
        }))
      }
    }
  }).catch(error => {
    console.error(error)
    throw error
  })
}

function appendToQueue (ID, queueItem) {
  for (let i = 0; i < queues.length; i++) {
    if (queues[i].ID === ID) {
      queues[i].queue.push(queueItem)
      console.log(queues[i].queue)
    }
  }
}