import { setHours, setMinutes, addDays, differenceInCalendarDays } from 'date-fns'
import moment from 'moment'

export default {
	generateTimelineTasks(subtasks, date, employee) {
		const { tasks, blockers, homeoffices } = this.generateTimelineEvents(subtasks, employee, date)
		const { nonWorkingHours }              = this.generateTimelineNonWorkingHours(date, employee)

		return {
			tasks,
			blockers,
			nonWorkingHours,
			homeoffices
		}
	},

	getUnscheduledTime(subtasks) {
		let unscheduledTime = 0
		subtasks.forEach(subtask => unscheduledTime += (subtask.duration - subtask.spent_time))

		return unscheduledTime
	},

	getScheduledTime(subtasks) {
		let scheduledTime = 0
		subtasks.forEach(subtask => scheduledTime += subtask.spent_time)

		return scheduledTime
	},

	isWeekend(date) {
		return moment(date).day() % 6 == 0
	},

	generateTimelineEvents(subtasks, employee, date) {
		let blockers  = []
		const tasks = []

		subtasks.forEach(subtask => {
			if (['blocker', 'adhoc', 'home_office', 'vacation', 'free_day', 'office365_blocker'].includes(subtask.type)) {
				blockers = [...blockers, ...this._generateEventsFromBlocker(subtask, date)]
			} else {
				subtask.timeblocks?.forEach((timeblock) => {
					tasks.push(this._composeTimelineEvent(subtask, employee, date, timeblock))
				})
			}
		})

		return {
			tasks,
			blockers: blockers.filter(blocker => blocker.type != 'home_office'),
			homeoffices: blockers.filter(blocker => blocker.type == 'home_office')
		}
	},

	_composeTimelineEvent(subtask, employee, date, timeblock) {
		const diffInDays = differenceInCalendarDays(date, new Date(timeblock.start))

		// console.log('subtask', subtask.type)

		let type = 'subtask'

		if (subtask.type == 'office365')
			type = 'office365'

		return {
			id: subtask.id,
			start: addDays(new Date(timeblock.start), diffInDays),
			end: addDays(new Date(timeblock.end), diffInDays),
			master_task: subtask.master_task,
			date: new Date(timeblock.start),
			isWeekend: this.isWeekend(timeblock.start),
			initials: employee.name.charAt(0).toUpperCase() + employee.surname.charAt(0).toUpperCase(),
			split: this._getSplitFromDate(date, timeblock.start),
			project_code: subtask.project_code,
			subtask: subtask,
			type,
			_timeblock_id: timeblock.id,
			_timeblock_is_finished: timeblock.is_finished,
			_real_start: new Date(timeblock.start),
			_real_end: new Date(timeblock.end),
			draggable: type !== 'office365'
		}
	},

	_generateEventsFromBlocker(blocker, date) {
		const start = moment(blocker.start)
		const end 	= moment(blocker.end)

		const dates 	= start.isSame(end, 'date') ? [moment(start).format('YYYY-MM-DD')] : this._getDatesInRange(start, end)
		const blockers 	= dates.map(d => {
			const diffInDays = differenceInCalendarDays(date, new Date(d))
			const dStart = new Date(moment(d).set({hours: start.hours(), minutes: start.minutes()}).format('YYYY-MM-DD HH:mm'))
			const dEnd   = new Date(moment(d).set({hours: end.hours(), minutes: end.minutes()}).format('YYYY-MM-DD HH:mm'))

			return {
				blocker,
				split: this._getSplitFromDate(date, d),
				start: addDays(dStart, diffInDays),
				end: addDays(dEnd, diffInDays),
				date: new Date(d),
				type: blocker.type,
				isBlocker: true,
				initials: `${blocker.employee?.name[0]}${blocker.employee?.surname[0]}`,
				color: '#B00020',
				draggable: false,
				_real_start: dStart,
				_real_end: dEnd
			}
		})

		return blockers
	},

	_getDatesInRange(start, end) {
		const dates = []

		while (start <= end) {
			dates.push(moment(start).format('YYYY-MM-DD'))
			start.add(1, 'day')
		}

		return dates
	},

	generateTimelineNonWorkingHours(date, employee) {
		const events = []

		const { start: dayStart, end: dayEnd } = this._getDayStartEnd(date)

		for (let i = 0; i < 7; i++) {
			events.push({
				title: "Non working hours",
				start: dayStart,
				end: this._setMinutesToDate(employee.work_start * 60, date),
				type: 'non-working-hours',
				split: i + 1,
				draggable: false
			})

			events.push({
				title: "Non working hours",
				start: this._setMinutesToDate(employee.work_end * 60, date),
				end: dayEnd,
				type: 'non-working-hours',
				split: i + 1,
				draggable: false
			})
		}

		return {nonWorkingHours: events}
	},

	_getSplitFromDate(date, start) {
		return differenceInCalendarDays(new Date(date), new Date(start))  * (-1) + 1
	},

	_getDifferenceInHours(date1, date2) {
		return this._getDifferenceInMinutes(date1, date2) / 60
	},

	_getDifferenceInMinutes(date1, date2) {
		let diff = (date1.getTime() - date2.getTime()) / 1000
		diff /= 60
		return Math.abs(Math.round(diff))
	},

	_getDayStartEnd(date) {
		return {
			start: this._setMinutesToDate(0, date),
			end: this._setMinutesToDate(1439, date)
		}
	},

	_setMinutesToDate(minutes, date) {
		const newDate = new Date(date)
		newDate.setHours(Math.floor(minutes / 60), minutes % 60, 0, 0)
		return newDate
	}
}