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

export default {
	generateTimelineTasks(subtasks, date, employee) {
		return [
			...this.generateTimelineEvents(subtasks, employee, date),
			...this.generateTimelineNonWorkingHours(date, employee)
		]
	},

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

		return unscheduledTime
	},

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

	generateTimelineEvents(subtasks, employee, date) {
		const events  = []

		subtasks.forEach(subtask => {
			subtask.timeblocks?.forEach((timeblock) => {
				events.push(this._composeTimelineEvent(subtask, employee, date, timeblock))
			})
		}) 

		return events
	},

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

		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,
			_timeblock_id: timeblock.id
		}
	},

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

		for (let i = 0; i < 7; i++) {
			nonWorkingHours.push({
				title: "Non working hours",
				start: setMinutes(setHours(date, 0), 0),
				end: setMinutes(setHours(date, employee.work_start), 0),
				nonWorking: true,
				split: i + 1,
				draggable: false
			})

			nonWorkingHours.push({
				title: "Non working hours",
				start: setMinutes(setHours(date, employee.work_end), 0),
				end: setMinutes(setHours(date, 23), 59),
				nonWorking: true,
				split: i + 1,
				draggable: false
			})
		}

		return nonWorkingHours
	},

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

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