Merge remote-tracking branch 'htwk-org/development'

# Conflicts:
#	backend/go.mod
#	frontend/index.html
#	frontend/package-lock.json
#	frontend/package.json
#	frontend/public/themes/lara-dark-blue/theme.css
#	frontend/public/themes/lara-dark-blue/theme.css.map
#	frontend/public/themes/lara-light-blue/theme.css
#	frontend/public/themes/lara-light-blue/theme.css.map
#	frontend/src/App.vue
#	frontend/src/components/DarkModeSwitcher.vue
#	frontend/src/i18n/index.ts
#	frontend/src/main.ts
#	frontend/src/router/index.ts
#	frontend/src/view/CalendarLink.vue
#	frontend/src/view/edit/EditCalendar.vue
#	frontend/vite.config.ts
#	reverseproxy.conf
#	reverseproxy.local.conf
#	services/data-manager/main.go
#	services/data-manager/model/roomOccupancyModel.go
#	services/data-manager/service/addRoute.go
#	services/data-manager/service/addSchedule.go
#	services/data-manager/service/db/dbGroups.go
#	services/data-manager/service/feed/feedFunctions.go
#	services/data-manager/service/fetch/sport/sportFetcher.go
#	services/data-manager/service/fetch/v1/fetchSeminarEventService.go
#	services/data-manager/service/fetch/v1/fetchSeminarGroupService.go
#	services/data-manager/service/fetch/v2/fetcher.go
#	services/data-manager/service/functions/filter.go
#	services/data-manager/service/functions/filter_test.go
#	services/data-manager/service/functions/time/parse.go
#	services/data-manager/service/room/roomService.go
#	services/data-manager/service/room/roomService_test.go
#	services/go.sum
#	services/ical/service/connector/grpc/client.go

services/data-manager/service/fetch/v2/fetcher.go

@@ -0,0 +1,207 @@
+//Calendar implementation for the HTWK Leipzig timetable. Evaluation and display of the individual dates in iCal format.
+//Copyright (C) 2024 HTWKalender support@htwkalender.de
+
+//This program is free software: you can redistribute it and/or modify
+//it under the terms of the GNU Affero General Public License as published by
+//the Free Software Foundation, either version 3 of the License, or
+//(at your option) any later version.
+
+//This program is distributed in the hope that it will be useful,
+//but WITHOUT ANY WARRANTY; without even the implied warranty of
+//MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+//GNU Affero General Public License for more details.
+
+//You should have received a copy of the GNU Affero General Public License
+//along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+package v2
+
+import (
+	"fmt"
+	"github.com/google/uuid"
+	"github.com/pocketbase/pocketbase"
+	"github.com/pocketbase/pocketbase/daos"
+	"golang.org/x/net/html"
+	"htwkalender/data-manager/model"
+	"htwkalender/data-manager/service/db"
+	"htwkalender/data-manager/service/fetch"
+	v1 "htwkalender/data-manager/service/fetch/v1"
+	"htwkalender/data-manager/service/functions"
+	localTime "htwkalender/data-manager/service/functions/time"
+	"log/slog"
+	"strings"
+)
+
+func ParseEventsFromRemote(app *pocketbase.PocketBase) (model.Events, error) {
+	savedRecords, err := FetchAllEventsAndSave(app, localTime.RealClock{})
+	if err != nil {
+		return nil, err
+	}
+	return savedRecords, nil
+}
+
+func FetchAllEventsAndSave(app *pocketbase.PocketBase, clock localTime.Clock) ([]model.Event, error) {
+	var savedRecords []model.Event
+	var err error = nil
+
+	var stubUrl = [2]string{
+		"https://stundenplan.htwk-leipzig.de/",
+		"/Berichte/Text-Listen;Veranstaltungsarten;name;" +
+			"Vp%0A" +
+			"Vw%0A" +
+			"V%0A" +
+			"Sp%0A" +
+			"Sw%0A" +
+			"S%0A" +
+			"Pp%0A" +
+			"Pw%0A" +
+			"P%0A" +
+			"ZV%0A" +
+			"Tut%0A" +
+			"Sperr%0A" +
+			"pf%0A" +
+			"wpf%0A" +
+			"fak%0A" +
+			"Pruefung%0A" +
+			"gebucht%0A" +
+			"Vertretung%0A" +
+			"Fremdveranst.%0A" +
+			"Buchen%0A" +
+			"%0A?&template=sws_modul&weeks=1-65&combined=yes",
+	}
+
+	// Fetch and save events for all semesters
+	for _, semester := range functions.CalculateSemesterList(clock) {
+		events, fetchErr := fetchAndSaveAllEventsForSemester(app, semester, stubUrl)
+		if fetchErr != nil {
+			return nil, fmt.Errorf("failed to fetch and save events for "+semester+": %w", "error", err)
+		}
+		savedRecords = append(savedRecords, events...)
+	}
+
+	return savedRecords, err
+}
+
+func fetchAndSaveAllEventsForSemester(
+	app *pocketbase.PocketBase,
+	semester string,
+	stubUrl [2]string,
+) ([]model.Event, error) {
+	var savedRecords []model.Event
+	url := stubUrl[0] + semester + stubUrl[1]
+	events, err := parseEventForOneSemester(url)
+
+	if err != nil {
+		return nil, fmt.Errorf("failed to parse events for "+semester+": %w", "error", err)
+	}
+
+	err = updateDatabase(app, events, "Sport", semester)
+
+	return savedRecords, err
+}
+
+func updateDatabase(app *pocketbase.PocketBase, eventsToBeAdded []model.Event, course string, semester string) error {
+
+	var addedEvents []model.Event
+	var err error
+
+	// to in transaction the events will be added and deleted
+	err = app.Dao().RunInTransaction(func(txDao *daos.Dao) error {
+		err = db.DeleteAllEventsRatherThenCourse(txDao, course, semester)
+		if err != nil {
+			return err
+		}
+
+		addedEvents, err = db.SaveEvents(eventsToBeAdded, txDao)
+		if err != nil {
+			return err
+		}
+
+		return nil
+	})
+	if err != nil {
+		return err
+	}
+
+	slog.Info("Added events: ", "events", len(addedEvents))
+
+	return nil
+}
+
+func parseEventForOneSemester(url string) ([]model.Event, error) {
+	// Fetch Webpage from URL
+	webpage, err := fetch.GetHTML(url)
+	if err != nil {
+		return nil, err
+	}
+
+	// Parse HTML to Node Tree
+	var doc *html.Node
+	doc, err = parseHTML(webpage)
+	if err != nil {
+		return nil, err
+	}
+
+	// Get all event tables and all day labels
+	eventTables := getEventTables(doc)
+	allDayLabels := getAllDayLabels(doc)
+	eventsWithCombinedWeeks := toEvents(eventTables, allDayLabels)
+
+	splitEventsByWeekVal := splitEventsByWeek(eventsWithCombinedWeeks)
+	events := splitEventsBySingleWeek(splitEventsByWeekVal)
+
+	if events == nil {
+		return nil, err
+	}
+
+	table := findFirstTable(doc)
+
+	if table == nil {
+		return nil, fmt.Errorf("failed to find first table")
+	}
+
+	semesterString := findFirstSpanWithClass(table, "header-0-2-0").FirstChild.Data
+	semester, year := extractSemesterAndYear(semesterString)
+	events = convertWeeksToDates(events, semester, year)
+	events, err = v1.SplitEventType(events)
+	if err != nil {
+		slog.Error("Error occurred while splitting event types: ", "error", err)
+		return nil, err
+	}
+	events = switchNameAndNotesForExam(events)
+	events = generateUUIDs(events)
+
+	return events, nil
+}
+
+// switch name and notes for Pruefung events when Note is not empty and Name starts with "Prüfungen" and contains email
+func switchNameAndNotesForExam(events []model.Event) []model.Event {
+	for i, event := range events {
+		if event.EventType == "Pruefung" {
+			if event.Notes != "" && strings.HasPrefix(event.Name, "Prüfungen") && strings.Contains(event.Name, "@") {
+				events[i].Name = event.Notes
+				events[i].Notes = event.Name
+			}
+		}
+	}
+	return events
+}
+
+func parseHTML(webpage string) (*html.Node, error) {
+	doc, err := html.Parse(strings.NewReader(webpage))
+	if err != nil {
+		return nil, err
+	}
+	return doc, nil
+}
+
+// generateUUIDs generates a UUID for each event based on the event name, course and semester
+// the UUID is used to identify the event in the database
+func generateUUIDs(events []model.Event) []model.Event {
+	for i, event := range events {
+		// generate a hash value from the event name, course and semester
+		hash := uuid.NewSHA1(uuid.NameSpaceOID, []byte(event.Name+event.Course))
+		events[i].UUID = hash.String()
+	}
+	return events
+}