Add Calendar Events widget, integrate ICS calendar parsing, and refine related UI components

apis/calendar/main.go

@@ -0,0 +1,89 @@
+package calendar
+
+import (
+	"ArinDash/config"
+	"sort"
+	"time"
+
+	"github.com/arran4/golang-ical"
+)
+
+type configFile struct {
+	Calendar calendarConfig
+}
+
+type calendarConfig struct {
+	ICS  []ICS
+	Icon string
+}
+
+type ICS struct {
+	Icon string
+	URL  string
+}
+
+type Event struct {
+	UID         string
+	Summary     string
+	Description string
+	Start       time.Time
+	End         time.Time
+	Location    string
+	Icon        string
+}
+
+func FetchEvents() []Event {
+	cfg := &configFile{}
+	config.LoadConfig(cfg)
+
+	events := make([]Event, 0)
+	for _, ic := range cfg.Calendar.ICS {
+		cal, err := ics.ParseCalendarFromUrl(ic.URL)
+		if err != nil {
+			panic(err)
+		}
+		for _, event := range cal.Events() {
+			startAt, err := event.GetStartAt()
+			if err != nil {
+				startAt = time.Now()
+			}
+			endAt, err := event.GetEndAt()
+			if err != nil {
+				endAt = startAt
+			}
+			events = append(events, Event{
+				UID:         getValue(event, ics.ComponentPropertyUniqueId),
+				Icon:        ic.Icon,
+				Summary:     getValue(event, ics.ComponentPropertySummary),
+				Description: getValue(event, ics.ComponentPropertyDescription),
+				Start:       startAt,
+				End:         endAt,
+				Location:    getValue(event, ics.ComponentPropertyLocation),
+			})
+		}
+	}
+	result := filter(events, func(i Event) bool {
+		return i.End.After(time.Now())
+	})
+	sort.Slice(result, func(i, j int) bool {
+		return result[i].Start.Before(result[j].Start)
+	})
+	return result
+}
+
+func getValue(event *ics.VEvent, property ics.ComponentProperty) string {
+	ianaProperty := event.GetProperty(property)
+	if ianaProperty == nil {
+		return ""
+	}
+	return ianaProperty.Value
+}
+
+func filter[T any](ss []T, test func(T) bool) (ret []T) {
+	for _, s := range ss {
+		if test(s) {
+			ret = append(ret, s)
+		}
+	}
+	return
+}