package models

import (
	"arbeitszeitmessung/helper"
	"database/sql"
	"fmt"
	"log"
	"net/url"
	"sort"
	"strconv"
	"time"
)

type SameBookingError struct{}

func (e SameBookingError) Error() string {
	return "the same booking already exists!"
}

type Booking struct {
	CardUID    string    `json:"card_uid"`
	GeraetID   int16     `json:"geraet_id"`
	CheckInOut int16     `json:"check_in_out"`
	Timestamp  time.Time `json:"timestamp"`
	CounterId  int       `json:"counter_id"`
}

var DB *sql.DB

func (b *Booking) New(card_uid string, geraet_id int16, check_in_out int16) Booking {
	return Booking{
		CardUID:    card_uid,
		GeraetID:   geraet_id,
		CheckInOut: check_in_out,
	}
}

func (b *Booking) FromUrlParams(params url.Values) Booking {
	var booking Booking
	if _check_in_out, err := strconv.Atoi(params.Get("check_in_out")); err == nil {
		booking.CheckInOut = int16(_check_in_out)
	}
	if _geraet_id, err := strconv.Atoi(params.Get("geraet_id")); err == nil {
		booking.GeraetID = int16(_geraet_id)
	}
	booking.CardUID = params.Get("card_uid")
	return booking
}

func (b *Booking) Verify() bool {
	//check for overlapping time + arbeitszeit verstoß
	if b.CardUID == "" { //|| b.GeraetID == 0 || b.CheckInOut == 0 {
		return false
	}
	return true
}

func (b *Booking) Insert() error {
	if !checkLastBooking(*b) {
		return SameBookingError{}
	}
	stmt, err := DB.Prepare((`INSERT INTO anwesenheit (card_uid, geraet_id, check_in_out) VALUES ($1, $2, $3) RETURNING counter_id, timestamp`))
	if err != nil {
		return err
	}
	err = stmt.QueryRow(b.CardUID, b.GeraetID, b.CheckInOut).Scan(&b.CounterId, &b.Timestamp)
	if err != nil {
		return err
	}
	return nil
}

func (b *Booking) InsertWithTimestamp() error {
	if b.Timestamp.IsZero() {
		return b.Insert()
	}
	stmt, err := DB.Prepare((`INSERT INTO anwesenheit (card_uid, geraet_id, check_in_out, timestamp) VALUES ($1, $2, $3, $4) RETURNING counter_id`))
	if err != nil {
		return err
	}
	err = stmt.QueryRow(b.CardUID, b.GeraetID, b.CheckInOut, b.Timestamp).Scan(&b.CounterId)
	if err != nil {
		return err
	}
	return nil
}

func (b *Booking) GetBookingById(booking_id int) (Booking, error) {
	var booking Booking
	qStr, err := DB.Prepare((`SELECT counter_id, timestamp, card_uid, geraet_id, check_in_out FROM anwesenheit WHERE counter_id = $1`))
	if err != nil {
		return booking, err
	}
	err = qStr.QueryRow(booking_id).Scan(&booking.CounterId, &booking.Timestamp, &booking.CardUID, &booking.GeraetID, &booking.CheckInOut)
	if err != nil {
		return booking, err
	}
	// if !booking.Verify() {
	// 	fmt.Printf("Booking verification failed! %d", )
	// 	return booking, nil
	// }
	return booking, nil
}

// Gets all booking based on a card uid
//
// optional filter parameter
func (b *Booking) GetBookingsByCardID(card_uid string, tsFrom time.Time, tsTo time.Time) ([]Booking, error) {
	qStr, err := DB.Prepare((`SELECT counter_id, timestamp, card_uid, geraet_id, check_in_out FROM anwesenheit WHERE card_uid = $1 AND timestamp BETWEEN $2 AND $3 ORDER BY timestamp`))
	if err != nil {
		return nil, err
	}
	defer qStr.Close()
	var bookings []Booking
	rows, err := qStr.Query(card_uid, tsFrom, tsTo)
	if err == sql.ErrNoRows {
		return bookings, err
	}
	if err != nil {
		return nil, err
	}
	defer rows.Close()
	for rows.Next() {
		var booking Booking
		if err := rows.Scan(&booking.CounterId, &booking.Timestamp, &booking.CardUID, &booking.GeraetID, &booking.CheckInOut); err != nil {
			return bookings, err
		}
		bookings = append(bookings, booking)
	}
	if err = rows.Err(); err != nil {
		return bookings, err
	}
	return bookings, nil
}

func (b *Booking) GetBookingsGrouped(card_uid string, tsFrom time.Time, tsTo time.Time) ([]WorkDay, error) {
	var grouped = make(map[string][]Booking)
	bookings, err := b.GetBookingsByCardID(card_uid, tsFrom, tsTo)
	if err != nil {
		log.Println("Failed to get bookings", err)
		return []WorkDay{}, nil
	}
	for _, booking := range bookings {
		day := booking.Timestamp.Truncate(24 * time.Hour)
		key := day.Format("2006-01-02")
		grouped[key] = append(grouped[key], booking)
	}

	var result []WorkDay
	for key, bookings := range grouped {
		day, _ := time.Parse("2006-01-02", key)
		sort.Slice(bookings, func(i, j int) bool {
			return bookings[i].Timestamp.Before(bookings[j].Timestamp)
		})
		workDay := WorkDay{Day: day, Bookings: bookings}
		workDay.getWorkTime()
		result = append(result, workDay)
	}

	sort.Slice(result, func(i, j int) bool {
		return result[i].Day.After(result[j].Day)
	})

	return result, nil
}

func (b Booking) Save() {
	qStr, err := DB.Prepare((`UPDATE "anwesenheit" SET "card_uid" = $2, "geraet_id" = $3, "check_in_out" = $4, "timestamp" = $5 WHERE "counter_id" = $1;`))
	if err != nil {
		log.Fatalf("Error preparing query: %v", err)
		return
	}
	_, err = qStr.Query(b.CounterId, b.CardUID, b.GeraetID, b.CheckInOut, b.Timestamp)
	if err != nil {
		log.Fatalf("Error executing query: %v", err)
		return
	}
}

func (b *Booking) GetBookingType() string {
	debug := (helper.GetEnv("GO_ENV", "production") == "debug")
	switch b.CheckInOut {
	case 1: //manuelle Änderung
		return "kommen"
	case 3:
		if debug {
			return "kommen manuell"
		}
		return "kommen"
	case 2: //manuelle Änderung
		return "gehen"
	case 4:
		if debug {
			return "gehen manuell"
		}
		return "gehen"
	case 254:
		return "abgemeldet"
	default:
		return "Buchungs Typ unbekannt"
	}
}

func (b *Booking) Update(nb Booking) {
	if b.CheckInOut != nb.CheckInOut && nb.CheckInOut != 0 {
		b.CheckInOut = nb.CheckInOut
	}
	if b.CardUID != nb.CardUID && nb.CardUID != "" {
		b.CardUID = nb.CardUID
	}
	if b.GeraetID != nb.GeraetID && nb.GeraetID != 0 {
		b.GeraetID = nb.GeraetID
	}
	if b.Timestamp != nb.Timestamp {
		b.Timestamp = nb.Timestamp
	}
}

func checkLastBooking(b Booking) bool {
	var check_in_out int
	stmt, err := DB.Prepare((`SELECT check_in_out FROM "anwesenheit" WHERE "card_uid" = $1 ORDER BY "timestamp" DESC LIMIT 1;`))
	if err != nil {
		log.Fatalf("Error preparing query: %v", err)
		return false
	}
	err = stmt.QueryRow(b.CardUID).Scan(&check_in_out)
	if err == sql.ErrNoRows {
		return true
	}
	if err != nil {
		log.Println("Error checking last booking: ", err)
		return false
	}
	if int16(check_in_out)%2 == b.CheckInOut%2 {
		return false
	}
	return true
}

func (b *Booking) UpdateTime(newTime time.Time) {
	hour, minute, _ := newTime.Clock()
	if hour == b.Timestamp.Hour() && minute == b.Timestamp.Minute() {
		return
	}
	// TODO: add check for time overlap

	var newBooking Booking
	newBooking.Timestamp = time.Date(b.Timestamp.Year(), b.Timestamp.Month(), b.Timestamp.Day(), hour, minute, 0, 0, b.Timestamp.Location())
	if b.CheckInOut < 3 {
		newBooking.CheckInOut = b.CheckInOut + 2
	}
	if b.CheckInOut == 254 {
		newBooking.CheckInOut = 4
	}
	log.Println("Updating")
	b.Update(newBooking)
	b.Verify()
	b.Save()
}

func (b *Booking) ToString() string {
	return fmt.Sprintf("Booking %d: at: %s, as type: %d", b.CounterId, b.Timestamp.Format("15:04"), b.CheckInOut)
}