package main

import (
	"fmt"
	"log"
	"time"

	"google.golang.org/api/calendar/v3"
)

type Class struct {
	Summary string
	Start string
	End string
	Students []string
	Days []time.Weekday
	Tags map[string]string
	Zoom string
}

func (c Class) happensOnDay(t time.Time) bool {
	for _, day := range c.Days {
		if day == t.Weekday() {
			return true
		}
	}
	return false
}

func (c Class) tagsMatch(t time.Time) bool {
	for key, value := range c.Tags {
		tagValue, err := getTagAt(key, t)
		if err != nil {
			log.Fatal(err)
		}
		if value != tagValue {
			return false
		}
	}
	return true
}

func (c Class) buildEvent(t time.Time) *calendar.Event {
	dateStr := t.Format("2006-01-02")

	ev := &calendar.Event{
		Summary: c.Summary,
		Start: &calendar.EventDateTime{
			DateTime: fmt.Sprintf("%sT%s:00", dateStr, c.Start),
			TimeZone: "US/Pacific",
		},
		End: &calendar.EventDateTime{
			DateTime: fmt.Sprintf("%sT%s:00", dateStr, c.End),
			TimeZone: "US/Pacific",
		},
		Attendees: []*calendar.EventAttendee{},
	}

	attendees := c.Students
	if len(attendees) == 0 {
		attendees = allStudents
	}

	for _, student := range attendees {
		ev.Attendees = append(
			ev.Attendees,
			&calendar.EventAttendee{
				Email: student,
			},
		)
	}

	if c.Zoom != "" {
		ev.Description = fmt.Sprintf(`Zoom: %s`, c.Zoom)
	}

	return ev
}