package main

import (
	"flag"
	"fmt"
	"io/ioutil"
	"log"
	"time"

	"golang.org/x/oauth2/google"
	"google.golang.org/api/calendar/v3"
)

var calName = flag.String("calendar", "", "name of calendar")
var days = flag.Int("days", 0, "number of days in the future")

var allStudents = []string{
	"oliver.park@heliosns.org",
}

var greenStudents = []string{
	"oliver.park@heliosns.org",
}

var weekDays = []time.Weekday{time.Monday, time.Tuesday, time.Wednesday, time.Thursday, time.Friday}
var weekDaysButFriday = []time.Weekday{time.Monday, time.Tuesday, time.Wednesday, time.Thursday}

var classes = []Class {
	Class{
		Summary: "Morning Circle",
		Start: "08:30",
		End: "09:00",
		Days: weekDaysButFriday,
		Zoom: "https://us02web.zoom.us/j/2274643506?pwd=Nm5NUXMwOVJKbEUzNE5VSkZCQzJ2UT09",
	},
	Class{
		Summary: "Community Meeting",
		Start: "08:30",
		End: "09:00",
		Days: []time.Weekday{time.Friday},
		Zoom: "https://zoom.us/j/96371462107",
	},
	Class{
		Summary: "Math (Claudia & Rachel)",
		Start: "09:00",
		End: "09:40",
		Days: weekDays,
		Zoom: "https://us02web.zoom.us/j/2274643506?pwd=Nm5NUXMwOVJKbEUzNE5VSkZCQzJ2UT09",
		Students: []string{
			"oliver.park@heliosns.org",
		},
	},
	Class{
		Summary: "Dreambox",
		Start: "09:40",
		End: "10:00",
		Days: weekDays,
	},
	Class{
		Summary: "Theme",
		Start: "10:30",
		End: "11:30",
		Days: weekDaysButFriday,
		Zoom: "https://us02web.zoom.us/j/2274643506?pwd=Nm5NUXMwOVJKbEUzNE5VSkZCQzJ2UT09",
	},
	Class{
		Summary: "SEL",
		Start: "10:30",
		End: "11:15",
		Days: []time.Weekday{time.Friday},
		Zoom: "https://us02web.zoom.us/j/2274643506?pwd=Nm5NUXMwOVJKbEUzNE5VSkZCQzJ2UT09",
	},
	Class{
		Summary: "Literacy (Green)",
		Start: "11:30",
		End: "12:00",
		Days: []time.Weekday{time.Monday, time.Wednesday},
		Zoom: "https://us02web.zoom.us/j/2274643506?pwd=Nm5NUXMwOVJKbEUzNE5VSkZCQzJ2UT09",
		Students: greenStudents,
	},
	Class{
		Summary: "PE (Yellow/Green)",
		Start: "11:30",
		End: "12:00",
		Days: []time.Weekday{time.Tuesday},
		Zoom: "https://zoom.us/j/97472507748?pwd=cW5vUFhyUjNTS2toWlZGN254U1ZqZz09",
		Students: greenStudents,
	},
	Class{
		Summary: "iLab (Yellow/Green)",
		Start: "11:30",
		End: "12:00",
		Days: []time.Weekday{time.Thursday},
		Zoom: "https://us02web.zoom.us/j/86403635026?pwd=S2t1WkN2dnNJZlFkejdEbjRsUmNNUT09",
		Students: greenStudents,
	},
	Class{
		Summary: "Library",
		Start: "11:30",
		End: "12:00",
		Days: []time.Weekday{time.Friday},
		Zoom: "https://us02web.zoom.us/my/helioslibrary?pwd=cWd4RjNqNXZXNjRjM2dYQVhYeS9Xdz09",
	},
	Class{
		Summary: "Spanish",
		Start: "12:45",
		End: "13:30",
		Days: []time.Weekday{time.Monday, time.Tuesday, time.Wednesday},
		Zoom: "https://zoom.us/j/95144364579?pwd=cGdwNTZIOE42Y0syeVcwVEFhZ1JxZz09",
		Students: []string{
			"oliver.park@heliosns.org",
		},
	},
	Class{
		Summary: "Music & Movement (Blue/Green)",
		Start: "12:45",
		End: "13:30",
		Days: []time.Weekday{time.Friday},
		Zoom: "https://zoom.us/j/96449009866?pwd=dlBHYUwxaDRReFhjVmRKZ0Vhdjdkdz09",
		Students: greenStudents,
	},
	Class{
		Summary: "Art (Blue/Green)",
		Start: "14:00",
		End: "14:45",
		Days: []time.Weekday{time.Friday},
		Zoom: "https://us02web.zoom.us/j/85434303018?pwd=c3EzQVNCMmk0L0o4bVF4QW85RTZHZz09",
		Students: greenStudents,
	},
	Class{
		Summary: "Closing Circle",
		Start: "15:00",
		End: "15:15",
		Days: []time.Weekday{time.Friday},
		Zoom: "https://us02web.zoom.us/j/2274643506?pwd=Nm5NUXMwOVJKbEUzNE5VSkZCQzJ2UT09",
	},
}

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

func main() {
	flag.Parse()

	b, err := ioutil.ReadFile("credentials.json")
	if err != nil {
		log.Fatal(err)
	}

	// If modifying these scopes, delete your previously saved token.json.
	config, err := google.ConfigFromJSON(b, calendar.CalendarScope)
	if err != nil {
		log.Fatal(err)
	}
	client, err := getClient(config)
	if err != nil {
		log.Fatal(err)
	}

	srv, err := calendar.New(client)
	if err != nil {
		log.Fatal(err)
	}

	calendars, err := srv.CalendarList.List().Do()
	if err != nil {
		log.Fatal(err)
	}
	var myCal *calendar.CalendarListEntry
	for _, item := range calendars.Items {
		if item.Summary == *calName {
			myCal = item
			break
		}
	}
	if myCal == nil {
		log.Fatalf("calendar '%s' not found", *calName)
	}

	loc, err := time.LoadLocation("US/Pacific")
	if err != nil {
		log.Fatal(err)
	}

	now := time.Now().In(loc)

	for i := 0; i < *days; i++ {
		date := now.Add(time.Duration(i * 24) * time.Hour)
		dateStr := date.Format("2006-01-02")

		for _, class := range classes {
			found := false
			for _, day := range class.Days {
				if day == date.Weekday() {
					found = true
					break
				}
			}
			if !found {
				continue
			}

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

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

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

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

			_, err := srv.Events.Insert(myCal.Id, ev).Do()
			if err != nil {
				log.Fatal(err)
			}
		}
	}


	/*
	ev := &calendar.Event{
		Summary: "Test event",
		Start: &calendar.EventDateTime{
			DateTime: "2020-09-09T16:00:00",
			TimeZone: "US/Pacific",
		},
		End: &calendar.EventDateTime{
			DateTime: "2020-09-09T17:00:00",
			TimeZone: "US/Pacific",
		},
		Attendees: []*calendar.EventAttendee{
			&calendar.EventAttendee{
				Email: "oliver.park@heliosns.org",
			},
		},
	}

	res, err := srv.Events.Insert(myCal.Id, ev).Do()
	if err != nil {
		log.Fatal(err)
	}

	log.Printf("%#v", res)
	*/

	/*
	t := time.Now().Format(time.RFC3339)
	events, err := srv.Events.List(myCal.Id).ShowDeleted(false).
		SingleEvents(true).TimeMin(t).MaxResults(250).OrderBy("startTime").Do()
	if err != nil {
		log.Fatal(err)
	}

	for _, item := range events.Items {
		date := item.Start.DateTime
		if date == "" {
			date = item.Start.Date
		}
		log.Printf("%v (%v)", item.Summary, date)
	}
	*/
}