import {
	IExecuteFunctions,
} from 'n8n-core';

import {
	IDataObject,
	INodeExecutionData,
	INodeType,
	INodeTypeDescription,
} from 'n8n-workflow';

import {
	promisify,
} from 'util';

import * as moment from 'moment-timezone';

import * as ics from 'ics';

const createEvent = promisify(ics.createEvent);

export class ICalendar implements INodeType {
	description: INodeTypeDescription = {
		displayName: 'iCalendar',
		name: 'iCal',
		icon: 'fa:calendar',
		group: ['input'],
		version: 1,
		subtitle: '={{$parameter["operation"]}}',
		description: 'Create iCalendar file',
		defaults: {
			name: 'iCalendar',
			color: '#408000',
		},
		inputs: ['main'],
		outputs: ['main'],
		credentials: [],
		properties: [
			{
				displayName: 'Operation',
				name: 'operation',
				type: 'options',
				options: [
					{
						name: 'Create Event File',
						value: 'createEventFile',
					},
				],
				default: 'createEventFile',
			},
			{
				displayName: 'Event Title',
				name: 'title',
				type: 'string',
				default: '',
			},
			{
				displayName: 'Start',
				name: 'start',
				type: 'dateTime',
				default: '',
				required: true,
				description: 'Date and time at which the event begins. (For all-day events, the time will be ignored.)',
			},
			{
				displayName: 'End',
				name: 'end',
				type: 'dateTime',
				default: '',
				required: true,
				description: 'Date and time at which the event ends. (For all-day events, the time will be ignored.)',
			},
			{
				displayName: 'All Day',
				name: 'allDay',
				type: 'boolean',
				default: false,
				description: 'Whether the event lasts all day or not.',
			},
			{
				displayName: 'Binary Property',
				name: 'binaryPropertyName',
				type: 'string',
				default: 'data',
				required: true,
				description: 'The field that your iCalendar file will be available under in the output.',
			},
			{
				displayName: 'Additional Fields',
				name: 'additionalFields',
				type: 'collection',
				placeholder: 'Add Field',
				default: {},
				displayOptions: {
					show: {
						operation: [
							'createEventFile',
						],
					},
				},
				options: [
					{
						displayName: 'Attendees',
						name: 'attendeesUi',
						type: 'fixedCollection',
						typeOptions: {
							multipleValues: true,
						},
						placeholder: 'Add Attendee',
						default: {},
						options: [
							{
								displayName: 'Attendees',
								name: 'attendeeValues',
								values: [
									{
										displayName: 'Name',
										name: 'name',
										type: 'string',
										required: true,
										default: '',
									},
									{
										displayName: 'Email',
										name: 'email',
										type: 'string',
										required: true,
										default: '',
									},
									{
										displayName: 'RSVP',
										name: 'rsvp',
										type: 'boolean',
										default: false,
										description: `Whether the attendee has to confirm attendance or not.`,
									},
								],
							},
						],
					},
					{
						displayName: 'Busy Status',
						name: 'busyStatus',
						type: 'options',
						options: [
							{
								name: 'Busy',
								value: 'BUSY',
							},
							{
								name: 'Tentative',
								value: 'TENTATIVE',
							},
						],
						default: '',
						description: 'Used to specify busy status for Microsoft applications, like Outlook.',
					},
					{
						displayName: 'Calendar Name',
						name: 'calName',
						type: 'string',
						default: '',
						description: 'Specifies the calendar (not event) name. Used by Apple iCal and Microsoft Outlook (<a href="https://docs.microsoft.com/en-us/openspecs/exchange_server_protocols/ms-oxcical/1da58449-b97e-46bd-b018-a1ce576f3e6d">spec</a>).',
					},
					{
						displayName: 'Description',
						name: 'description',
						type: 'string',
						default: '',
					},
					{
						displayName: 'File Name',
						name: 'fileName',
						type: 'string',
						default: '',
						description: 'The name of the file to be generated. Default value is event.ics.',
					},
					{
						displayName: 'Geolocation',
						name: 'geolocationUi',
						type: 'fixedCollection',
						typeOptions: {
							multipleValues: false,
						},
						placeholder: 'Add Geolocation',
						default: {},
						options: [
							{
								displayName: 'Geolocation',
								name: 'geolocationValues',
								values: [
									{
										displayName: 'Latitude',
										name: 'lat',
										type: 'string',
										default: '',
									},
									{
										displayName: 'Longitude',
										name: 'lon',
										type: 'string',
										default: '',
									},
								],
							},
						],
					},
					{
						displayName: 'Location',
						name: 'location',
						type: 'string',
						default: '',
						description: 'The intended venue.',
					},
					{
						displayName: 'Recurrence Rule',
						name: 'recurrenceRule',
						type: 'string',
						default: '',
						description: `A rule to define the repeat pattern of the event (RRULE). (<a href="https://icalendar.org/rrule-tool.html">Rule generator</a>)`,
					},
					{
						displayName: 'Organizer',
						name: 'organizerUi',
						type: 'fixedCollection',
						typeOptions: {
							multipleValues: false,
						},
						placeholder: 'Add Organizer',
						default: {},
						options: [
							{
								displayName: 'Organizer',
								name: 'organizerValues',
								values: [
									{
										displayName: 'Name',
										name: 'name',
										type: 'string',
										default: '',
										required: true,
									},
									{
										displayName: 'Email',
										name: 'email',
										type: 'string',
										default: '',
										required: true,
									},
								],
							},
						],
					},
					{
						displayName: 'Sequence',
						name: 'sequence',
						type: 'number',
						default: 0,
						description: 'When sending an update for an event (with the same uid), defines the revision sequence number.',
					},
					{
						displayName: 'Status',
						name: 'status',
						type: 'options',
						options: [
							{
								name: 'Confirmed',
								value: 'CONFIRMED',
							},
							{
								name: 'Cancelled',
								value: 'CANCELLED',
							},
							{
								name: 'Tentative',
								value: 'TENTATIVE',
							},
						],
						default: 'CONFIRMED',
					},
					{
						displayName: 'UID',
						name: 'uid',
						type: 'string',
						default: '',
						description: `Universally unique id for the event (will be auto-generated if not specified here). Should be globally unique.`,
					},
					{
						displayName: 'URL',
						name: 'url',
						type: 'string',
						default: '',
						description: 'URL associated with event.',
					},
				],
			},
		],
	};

	async execute(this: IExecuteFunctions): Promise<INodeExecutionData[][]> {
		const items = this.getInputData();
		const length = (items.length as unknown) as number;
		const returnData: INodeExecutionData[] = [];
		const operation = this.getNodeParameter('operation', 0) as string;
		if (operation === 'createEventFile') {
			for (let i = 0; i < length; i++) {
				const title = this.getNodeParameter('title', i) as string;
				const allDay = this.getNodeParameter('allDay', i) as boolean;
				const start = this.getNodeParameter('start', i) as string;
				let end = this.getNodeParameter('end', i) as string;
				end = (allDay) ? moment(end).utc().add(1, 'day').format() as string : end;
				const binaryPropertyName = this.getNodeParameter('binaryPropertyName', i) as string;
				const additionalFields = this.getNodeParameter('additionalFields', i) as IDataObject;
				let fileName = 'event.ics';

				let eventStart = moment(start).toArray().splice(0, (allDay) ? 3 : 6) as ics.DateArray;
				eventStart[1]++;
				let eventEnd = moment(end).toArray().splice(0, (allDay) ? 3 : 6) as ics.DateArray;
				eventEnd[1]++;

				if (additionalFields.fileName) {
					fileName = additionalFields.fileName as string;
				}

				const data: ics.EventAttributes = {
					title,
					start: eventStart,
					end: eventEnd,
					startInputType: 'utc',
					endInputType: 'utc',
				};

				if (additionalFields.geolocationUi) {
					data.geo = (additionalFields.geolocationUi as IDataObject).geolocationValues as ics.GeoCoordinates;
					delete additionalFields.geolocationUi;
				}

				if (additionalFields.organizerUi) {
					data.organizer = (additionalFields.organizerUi as IDataObject).organizerValues as ics.Person;
					delete additionalFields.organizerUi;
				}

				if (additionalFields.attendeesUi) {
					data.attendees = (additionalFields.attendeesUi as IDataObject).attendeeValues as ics.Attendee[];
					delete additionalFields.attendeesUi;
				}

				Object.assign(data, additionalFields);
				const buffer = Buffer.from(await createEvent(data) as string);
				const binaryData = await this.helpers.prepareBinaryData(buffer, fileName, 'text/calendar');
				returnData.push(
					{
						json: {},
						binary: {
							[binaryPropertyName]: binaryData,
						},
					},
				);
			}
		}
		return [returnData];
	}
}