plutoapi-v2/src/models/dhbw-rapla-changes/changes/changes.service.ts

import * as dotenv from 'dotenv';
import {Event} from './Event.interface';
import {Change} from './Change.interface';
import {RaPlaChangesDB} from '../DHBWRaPlaChanges.db';

dotenv.config();

export const getChanges = async (course: string, week: string): Promise<Event[]> => {
	let conn = await RaPlaChangesDB.getConnection();
	try {
		let relevantEventsRows = await conn.query('SELECT DISTINCT(entry_id) FROM rapla_changes WHERE new_start > ? AND new_start < DATE_ADD(?, INTERVAL 7 DAY)', [week, week]);

		let relevantEventIds: string[] = [];
		relevantEventsRows.forEach((row: { entry_id: string; }) => {
			relevantEventIds.push(row.entry_id);
		});

		if (relevantEventIds.length < 1) {
			return [];
		}

		let rows = await conn.query('SELECT c.change_id, c.entry_id, c.change_timestamp, c.isDeleted, c.new_summary, c.new_description, c.new_start, c.new_last_modified, c.new_end, c.new_created, c.new_location, c.new_organizer, c.new_categories, e.uid FROM rapla_changes c LEFT OUTER JOIN rapla_entries e ON c.entry_id = e.entry_id WHERE c.entry_id IN (?) ORDER BY c.change_id', [relevantEventIds]);

		let eventsMap = new Map();

		for (let row of rows) {
			let change: Change = {
				change_id: row.change_id,
				event_id: row.event_id,
				change_timestamp: row.change_timestamp,
				is_deleted: row.isDeleted,
				new_summary: row.new_summary,
				new_description: row.new_description,
				new_start: row.new_start,
				new_end: row.new_end,
				new_last_modified: row.new_last_modified,
				new_created: row.new_created,
				new_location: row.new_location,
				new_organizer: row.new_organizer,
				new_categories: row.new_categories,
				new_recurring: row.new_recurring
			};

			if (eventsMap.has(row.entry_id)) {
				let event = eventsMap.get(row.entry_id);

				// Only adjust these fields if the event is not deleted as otherwise they would be null
				if (!row.isDeleted) {
					event.latest_event_summary = row.new_summary;
					event.latest_start_date = row.new_start;
				}
				event.changes.push(change);

				eventsMap.set(row.entry_id, event);
			} else {
				let event: Event = {
					event_id: row.event_id,
					event_uid: row.uid,
					latest_event_summary: row.new_summary,
					latest_start_date: row.new_start,
					changes: [change]
				};

				eventsMap.set(row.entry_id, event);
			}
		}

		return Array.from(eventsMap.values()) as Event[];
	} catch (err) {
		throw err;
	} finally {
		// Return connection
		await conn.end();
	}
};

export const getEventById = async (course: string, id: string): Promise<Event> => {
	let conn = await RaPlaChangesDB.getConnection();
	try {
		let rows = await conn.query('SELECT c.change_id, c.entry_id, c.change_timestamp, c.isDeleted, c.new_summary, c.new_description, c.new_start, c.new_last_modified, c.new_end, c.new_created, c.new_location, c.new_organizer, c.new_categories, e.uid FROM rapla_changes c LEFT OUTER JOIN rapla_entries e ON c.entry_id = e.entry_id WHERE e.uid = ? ORDER BY c.change_id', id);

		let eventsMap = new Map();

		for (let row of rows) {
			let change: Change = {
				change_id: row.change_id,
				event_id: row.event_id,
				change_timestamp: row.change_timestamp,
				is_deleted: row.isDeleted,
				new_summary: row.new_summary,
				new_description: row.new_description,
				new_start: row.new_start,
				new_end: row.new_end,
				new_last_modified: row.new_last_modified,
				new_created: row.new_created,
				new_location: row.new_location,
				new_organizer: row.new_organizer,
				new_categories: row.new_categories,
				new_recurring: row.new_recurring
			};

			if (eventsMap.has(row.entry_id)) {
				let event = eventsMap.get(row.entry_id);

				// Only adjust these fields if the event is not deleted as otherwise they would be null
				if (!row.isDeleted) {
					event.latest_event_summary = row.new_summary;
					event.latest_start_date = row.new_start;
				}
				event.changes.push(change);

				eventsMap.set(row.entry_id, event);
			} else {
				let event: Event = {
					event_id: row.event_id,
					event_uid: row.uid,
					latest_event_summary: row.new_summary,
					latest_start_date: row.new_start,
					changes: [change]
				};

				eventsMap.set(row.entry_id, event);
			}
		}

		return Array.from(eventsMap.values())[0];
	} catch (err) {
		throw err;
	} finally {
		// Return connection
		await conn.end();
	}
};