package handlers

import (
	"encoding/json"
	"fmt"
	"go-udemy-web-1/internal/config"
	"go-udemy-web-1/internal/driver"
	"go-udemy-web-1/internal/forms"
	"go-udemy-web-1/internal/helpers"
	"go-udemy-web-1/internal/models"
	"go-udemy-web-1/internal/render"
	"go-udemy-web-1/internal/repository"
	"go-udemy-web-1/internal/repository/dbrepo"
	"log"
	"net/http"
	"strconv"
	"strings"
	"time"

	"github.com/go-chi/chi/v5"
)

// Repo the repository used by the handlers
var Repo *Repository

// Repository is the repository type
type Repository struct {
	App *config.AppConfig
	DB  repository.DatabaseRepo
}

// NewRepo creates a new repository
func NewRepo(a *config.AppConfig, db *driver.DB) *Repository {
	return &Repository{
		App: a,
		DB:  dbrepo.NewPostgresRepo(db.SQL, a),
	}
}

// NewTestRepo creates a new testing repository
func NewTestRepo(a *config.AppConfig) *Repository {
	return &Repository{
		App: a,
		DB:  dbrepo.NewTestingRepo(a),
	}
}

// NewHandlers sets the repository for the handlers
func NewHandlers(r *Repository) {
	Repo = r
}

// Home is the home page handler
func (m *Repository) Home(w http.ResponseWriter, r *http.Request) {
	render.Template(w, r, "home.page.tmpl", &models.TemplateData{})
}

// About is the about page handler
func (m *Repository) About(w http.ResponseWriter, r *http.Request) {
	// send the data to the template
	render.Template(w, r, "about.page.tmpl", &models.TemplateData{})
}

// Contact is the contact page handler
func (m *Repository) Contact(w http.ResponseWriter, r *http.Request) {
	render.Template(w, r, "contact.page.tmpl", &models.TemplateData{})
}

// Generals is the General's Quarters page handler
func (m *Repository) Generals(w http.ResponseWriter, r *http.Request) {
	render.Template(w, r, "generals.page.tmpl", &models.TemplateData{})
}

// Majors is the Major's Suite page handler
func (m *Repository) Majors(w http.ResponseWriter, r *http.Request) {
	render.Template(w, r, "majors.page.tmpl", &models.TemplateData{})
}

// MakeReservation is the make reservation page handler
func (m *Repository) MakeReservation(w http.ResponseWriter, r *http.Request) {
	// For the first time render emptyReservation so that this object is
	// filled with the info when sent back.
	res, ok := m.App.Session.Get(r.Context(), "reservation").(models.Reservation)
	if !ok {
		m.App.Session.Put(r.Context(), "error", "can't get reservation from session")
		http.Redirect(w, r, "/", http.StatusTemporaryRedirect)
		return
	}

	room, err := m.DB.GetRoomById(res.RoomID)
	if err != nil {
		m.App.Session.Put(r.Context(), "error", "can't find room")
		http.Redirect(w, r, "/", http.StatusTemporaryRedirect)
		return
	}

	res.Room.RoomName = room.RoomName
	m.App.Session.Put(r.Context(), "reservation", res)

	sd := res.StartDate.Format("2006-01-02")
	ed := res.EndDate.Format("2006-01-02")
	stringMap := make(map[string]string)
	stringMap["start_date"] = sd
	stringMap["end_date"] = ed

	data := make(map[string]interface{})
	data["reservation"] = res

	render.Template(w, r, "make-reservation.page.tmpl", &models.TemplateData{
		Form:      forms.New(nil),
		Data:      data,
		StringMap: stringMap,
	})
}

// PostMakeReservation is the make reservation page post handler
func (m *Repository) PostMakeReservation(w http.ResponseWriter, r *http.Request) {
	reservation, ok := m.App.Session.Get(r.Context(), "reservation").(models.Reservation)
	if !ok {
		m.App.Session.Put(r.Context(), "error", "can't get reservation from session")
		http.Redirect(w, r, "/", http.StatusTemporaryRedirect)
		return
	}

	if err := r.ParseForm(); err != nil {
		m.App.Session.Put(r.Context(), "error", "can't parse form")
		http.Redirect(w, r, "/", http.StatusTemporaryRedirect)
		return
	}

	form := forms.New(r.PostForm)

	form.Required("first_name", "last_name", "email")
	form.MinLength("first_name", 2)
	form.IsEmail("email")

	reservation.FirstName = form.Get("first_name")
	reservation.LastName = form.Get("last_name")
	reservation.Email = form.Get("email")
	reservation.Phone = form.Get("phone")

	// TODO: Should I check the validity of reservation.StartDate / EndDate?

	if !form.Valid() {
		data := make(map[string]interface{})
		data["reservation"] = reservation

		render.Template(w, r, "make-reservation.page.tmpl", &models.TemplateData{
			Data: data,
			Form: form,
		})
		return
	}

	newReservationID, err := m.DB.InsertReservation(reservation)
	if err != nil {
		m.App.Session.Put(r.Context(), "error", "can't insert reservation into database")
		http.Redirect(w, r, "/", http.StatusTemporaryRedirect)
		return
	}

	m.App.Session.Put(r.Context(), "reservation", reservation)

	restriction := models.RoomRestriction{
		StartDate:     reservation.StartDate,
		EndDate:       reservation.EndDate,
		ID:            reservation.ID,
		RoomID:        reservation.RoomID,
		ReservationID: newReservationID,
		RestrictionID: 1,
	}

	err = m.DB.InsertRoomRestriction(restriction)
	if err != nil {
		m.App.Session.Put(r.Context(), "error", "can't insert room restriction into database")
		http.Redirect(w, r, "/", http.StatusTemporaryRedirect)
		return
	}

	// send notif to guest
	htmlMessage := fmt.Sprintf(`
        <strong>Reservation Confirmation</strong><br>
        Dear %s: <br>
        This is to confirm your reservation from %s to %s.

    `, reservation.FirstName, reservation.StartDate.Format("2006-01-02"),
		reservation.EndDate.Format("2006-01-02"))

	msg := models.MailData{
		To:       reservation.Email,
		From:     "me@here.com",
		Subject:  "Reservation Confirmation",
		Content:  htmlMessage,
		Template: "drip.html",
	}

	m.App.MailChan <- msg

	// send notif to property owner
	htmlMessage = fmt.Sprintf(`
        <strong>Reservation Notification</strong><br>
        A reservation has been made for %s from %s to %s.

    `, reservation.Room.RoomName, reservation.StartDate.Format("2006-01-02"),
		reservation.EndDate.Format("2006-01-02"))

	msg = models.MailData{
		To:      "me@here.com",
		From:    "me@here.com",
		Subject: "Reservation Notification",
		Content: htmlMessage,
	}

	m.App.MailChan <- msg

	m.App.Session.Put(r.Context(), "reservation", reservation)

	http.Redirect(w, r, "/reservation-summary", http.StatusSeeOther)
}

// ReservationSummary is the reservation summary page handler
func (m *Repository) ReservationSummary(w http.ResponseWriter, r *http.Request) {
	reservation, ok := m.App.Session.Get(r.Context(), "reservation").(models.Reservation)
	if !ok {
		m.App.ErrorLog.Println("connot get item from session")
		m.App.Session.Put(r.Context(), "error", "Can't get reservation from session")
		http.Redirect(w, r, "/", http.StatusTemporaryRedirect)
	}

	m.App.Session.Remove(r.Context(), "reservation")

	data := make(map[string]interface{})
	data["reservation"] = reservation

	sd := reservation.StartDate.Format("2006-01-02")
	ed := reservation.EndDate.Format("2006-01-02")
	stringMap := map[string]string{
		"start_date": sd,
		"end_date":   ed,
	}

	render.Template(w, r, "reservation-summary.page.tmpl", &models.TemplateData{
		Data:      data,
		StringMap: stringMap,
	})
}

// Availability is the search for availability page handler
func (m *Repository) Availability(w http.ResponseWriter, r *http.Request) {
	render.Template(w, r, "availability.page.tmpl", &models.TemplateData{})
}

// PostAvailability is the search for availability page handler
func (m *Repository) PostAvailability(w http.ResponseWriter, r *http.Request) {
	if err := r.ParseForm(); err != nil {
		m.App.Session.Put(r.Context(), "error", "can't parse form")
		http.Redirect(w, r, "/", http.StatusTemporaryRedirect)
		return
	}
	start := r.Form.Get("start")
	end := r.Form.Get("end")

	layout := "2006-01-02"
	startDate, err := time.Parse(layout, start)
	if err != nil {
		m.App.Session.Put(r.Context(), "error", "Can't parse start date")
		http.Redirect(w, r, "/availability", http.StatusTemporaryRedirect)
		return
	}
	endDate, err := time.Parse(layout, end)
	if err != nil {
		m.App.Session.Put(r.Context(), "error", "Can't parse end date")
		http.Redirect(w, r, "/availability", http.StatusTemporaryRedirect)
		return
	}

	rooms, err := m.DB.SearchAvailabilityForAllRooms(startDate, endDate)
	if err != nil {
		m.App.Session.Put(r.Context(), "error", "Can't connect to database")
		http.Redirect(w, r, "/availability", http.StatusTemporaryRedirect)
		return
	}

	for _, i := range rooms {
		m.App.InfoLog.Println("ROOM:", i.ID, i.RoomName)
	}

	if len(rooms) == 0 {
		// No availability
		m.App.InfoLog.Println("No availability")
		m.App.Session.Put(r.Context(), "error", "No availability")
		http.Redirect(w, r, "/availability", http.StatusSeeOther)
		return
	}

	data := make(map[string]interface{})
	data["rooms"] = rooms

	res := models.Reservation{
		StartDate: startDate,
		EndDate:   endDate,
	}

	m.App.Session.Put(r.Context(), "reservation", res)

	render.Template(w, r, "choose-room.page.tmpl", &models.TemplateData{
		Data: data,
	})
}

type jsonResponse struct {
	Message   string `json:"message"`
	RoomID    string `json:"room_id"`
	StartDate string `json:"start_date"`
	EndDate   string `json:"end_date"`
	OK        bool   `json:"ok"`
}

// AvailabilityJSON is the search for availability page handler
func (m *Repository) AvailabilityJSON(w http.ResponseWriter, r *http.Request) {
	if err := r.ParseForm(); err != nil {
		// can't parse form, so return appropriate json
		resp := jsonResponse{
			OK:      false,
			Message: "Internal server error",
		}
		out, _ := json.MarshalIndent(resp, "", "    ")
		w.Header().Set("Content-Type", "application/json")
		w.Write(out)
		return
	}
	sd := r.Form.Get("start")
	ed := r.Form.Get("end")

	layout := "2006-01-02"
	startDate, err := time.Parse(layout, sd)
	if err != nil {
		resp := jsonResponse{
			OK:      false,
			Message: "Wrong startDate",
		}
		out, _ := json.MarshalIndent(resp, "", "    ")
		w.Header().Set("Content-Type", "application/json")
		w.Write(out)
		return
	}
	endDate, err := time.Parse(layout, ed)
	if err != nil {
		resp := jsonResponse{
			OK:      false,
			Message: "Wrong endDate",
		}
		out, _ := json.MarshalIndent(resp, "", "    ")
		w.Header().Set("Content-Type", "application/json")
		w.Write(out)
		return
	}

	roomID, err := strconv.Atoi(r.Form.Get("room_id"))
	if err != nil {
		resp := jsonResponse{
			OK:      false,
			Message: "Wrong roomID",
		}
		out, _ := json.MarshalIndent(resp, "", "    ")
		w.Header().Set("Content-Type", "application/json")
		w.Write(out)
		return
	}

	available, err := m.DB.SearchAvailabilityByDatesByRoomID(startDate, endDate, roomID)
	if err != nil {
		resp := jsonResponse{
			OK:      false,
			Message: "Error connecting to database",
		}
		out, _ := json.MarshalIndent(resp, "", "    ")
		w.Header().Set("Content-Type", "application/json")
		w.Write(out)
		return
	}

	resp := jsonResponse{
		OK:        available,
		Message:   "",
		StartDate: sd,
		EndDate:   ed,
		RoomID:    strconv.Itoa(roomID),
	}

	// No error check because all aspects of the json are handled
	out, _ := json.MarshalIndent(resp, "", "    ")

	w.Header().Set("Content-Type", "application/json")

	w.Write(out)
}

// ChooseRoom displays list of available rooms
func (m *Repository) ChooseRoom(w http.ResponseWriter, r *http.Request) {
	exploded := strings.Split(r.URL.RequestURI(), "/")
	roomID, err := strconv.Atoi(exploded[2])
	if err != nil {
		m.App.Session.Put(r.Context(), "error", "Can't parse roomID")
		http.Redirect(w, r, "/availability", http.StatusTemporaryRedirect)
		return
	}
	m.App.Session.Get(r.Context(), "reservation")

	res, ok := m.App.Session.Get(r.Context(), "reservation").(models.Reservation)
	if !ok {
		m.App.Session.Put(r.Context(), "error", "Can't get reservation from session")
		http.Redirect(w, r, "/availability", http.StatusTemporaryRedirect)
		return
	}

	res.RoomID = roomID
	m.App.Session.Put(r.Context(), "reservation", res)

	http.Redirect(w, r, "/make-reservation", http.StatusSeeOther)
}

// BookRoom takes URL parameters, builds a sessional variable, and takes user to make reservation
func (m *Repository) BookRoom(w http.ResponseWriter, r *http.Request) {
	roomID, _ := strconv.Atoi(r.URL.Query().Get("id"))
	sd := r.URL.Query().Get("s")
	ed := r.URL.Query().Get("e")

	var res models.Reservation

	layout := "2006-01-02"
	startDate, err := time.Parse(layout, sd)
	if err != nil {
		m.App.Session.Put(r.Context(), "error", "Can't parse start date")
		http.Redirect(w, r, "/availability", http.StatusTemporaryRedirect)
		return
	}
	endDate, err := time.Parse(layout, ed)
	if err != nil {
		m.App.Session.Put(r.Context(), "error", "Can't parse end date")
		http.Redirect(w, r, "/availability", http.StatusTemporaryRedirect)
		return
	}
	room, err := m.DB.GetRoomById(roomID)
	if err != nil {
		m.App.Session.Put(r.Context(), "error", "Can't parse roomId")
		http.Redirect(w, r, "/availability", http.StatusTemporaryRedirect)
		return
	}
	res.RoomID = roomID
	res.StartDate = startDate
	res.EndDate = endDate
	res.Room.RoomName = room.RoomName

	m.App.Session.Put(r.Context(), "reservation", res)
	http.Redirect(w, r, "/make-reservation", http.StatusSeeOther)
}

// ShowLogin shows the login screen
func (m *Repository) ShowLogin(w http.ResponseWriter, r *http.Request) {
	render.Template(w, r, "login.page.tmpl", &models.TemplateData{
		Form: forms.New(nil),
	})
}

// PostShowLogin handles logging the user in
func (m *Repository) PostShowLogin(w http.ResponseWriter, r *http.Request) {
	_ = m.App.Session.RenewToken(r.Context())

	err := r.ParseForm()
	if err != nil {
		m.App.Session.Put(r.Context(), "error", "Can't parse form")
		http.Redirect(w, r, "/user/login", http.StatusSeeOther)
		return
	}

	email := r.Form.Get("email")
	password := r.Form.Get("password")
	form := forms.New(r.PostForm)
	form.Required("email", "password")
	form.IsEmail("email")
	if !form.Valid() {
		render.Template(w, r, "login.page.tmpl", &models.TemplateData{
			Form: form,
		})
		return
	}

	id, _, err := m.DB.Authenticate(email, password)
	if err != nil {
		log.Println(err)
		m.App.Session.Put(r.Context(), "error", "Invalid login credentials")
		http.Redirect(w, r, "/user/login", http.StatusSeeOther)
		return
	}

	m.App.Session.Put(r.Context(), "user_id", id)
	m.App.Session.Put(r.Context(), "flash", "Logged in successfully")
	http.Redirect(w, r, "/admin/dashboard", http.StatusSeeOther)
}

// Logout logs a user out
func (m *Repository) Logout(w http.ResponseWriter, r *http.Request) {
	// TODO Use Redis to store the session. Check the documentation of scs package
	m.App.Session.Destroy(r.Context())
	m.App.Session.RenewToken(r.Context())
	http.Redirect(w, r, "/user/login", http.StatusSeeOther)
}

func (m *Repository) AdminDashboard(w http.ResponseWriter, r *http.Request) {
	render.Template(w, r, "admin-dashboard.page.tmpl", &models.TemplateData{})
}

// AdminNewReservations shows all new reservations in admin tool
func (m *Repository) AdminNewReservations(w http.ResponseWriter, r *http.Request) {
	reservations, err := m.DB.AllNewReservations()
	if err != nil {
		helpers.ServerError(w, err)
		return
	}
	data := make(map[string]interface{})
	data["reservations"] = reservations

	render.Template(w, r, "admin-new-reservations.page.tmpl", &models.TemplateData{
		Data: data,
	})
}

// AdminNewReservations shows all reservations in admin tool
func (m *Repository) AdminAllReservations(w http.ResponseWriter, r *http.Request) {
	reservations, err := m.DB.AllReservations()
	if err != nil {
		helpers.ServerError(w, err)
		return
	}
	data := make(map[string]interface{})
	data["reservations"] = reservations

	render.Template(w, r, "admin-all-reservations.page.tmpl", &models.TemplateData{
		Data: data,
	})
}

// AdminShowReservation shows the detail of a reservation
func (m *Repository) AdminShowReservation(w http.ResponseWriter, r *http.Request) {
	exploded := strings.Split(r.RequestURI, "/")
	id, err := strconv.Atoi(exploded[4])
	if err != nil {
		helpers.ServerError(w, err)
		return
	}
	src := exploded[3]

	stringMap := make(map[string]string)
	stringMap["src"] = src

	// get reservation from the database
	res, err := m.DB.GetReservationByID(id)
	if err != nil {
		helpers.ServerError(w, err)
		return
	}

	data := make(map[string]interface{})

	data["reservation"] = res

	render.Template(w, r, "admin-reservations-show.page.tmpl", &models.TemplateData{
		StringMap: stringMap,
		Data:      data,
		Form:      forms.New(nil),
	})
}

// AdminShowReservation shows the detail of a reservation
func (m *Repository) AdminPostShowReservation(w http.ResponseWriter, r *http.Request) {
	if err := r.ParseForm(); err != nil {
		helpers.ServerError(w, err)
		return
	}

	exploded := strings.Split(r.RequestURI, "/")
	id, err := strconv.Atoi(exploded[4])
	if err != nil {
		helpers.ServerError(w, err)
		return
	}
	src := exploded[3]

	stringMap := make(map[string]string)
	stringMap["src"] = src

	// get reservation from the database
	res, err := m.DB.GetReservationByID(id)
	if err != nil {
		helpers.ServerError(w, err)
		return
	}

	res.FirstName = r.Form.Get("first_name")
	res.LastName = r.Form.Get("last_name")
	res.Email = r.Form.Get("email")
	res.Phone = r.Form.Get("phone")

	// TODO error checking

	err = m.DB.UpdateReservation(res)
	if err != nil {
		helpers.ServerError(w, err)
		return
	}

	m.App.Session.Put(r.Context(), "flash", "Changes saved")
	http.Redirect(w, r, fmt.Sprintf("/admin/reservations-%s", src), http.StatusSeeOther)
}

// AdminReservationsCalendar displays the reservation calendar
func (m *Repository) AdminReservationsCalendar(w http.ResponseWriter, r *http.Request) {
	now := time.Now()

	if r.URL.Query().Get("y") != "" {
		year, _ := strconv.Atoi(r.URL.Query().Get("y"))
		month, _ := strconv.Atoi(r.URL.Query().Get("m"))
		now = time.Date(year, time.Month(month), 1, 0, 0, 0, 0, time.UTC)
	}

	data := make(map[string]interface{})
	data["now"] = now

	next := now.AddDate(0, 1, 0)
	last := now.AddDate(0, -1, 0)

	nextMonth := next.Format("01")
	nextMonthYear := next.Format("2006")

	lastMonth := last.Format("01")
	lastMonthYear := last.Format("2006")

	stringMap := make(map[string]string)
	stringMap["next_month"] = nextMonth
	stringMap["next_month_year"] = nextMonthYear
	stringMap["last_month"] = lastMonth
	stringMap["last_month_year"] = lastMonthYear
	stringMap["this_month"] = now.Format("01")
	stringMap["this_month_year"] = now.Format("2006")

	// get the first and last days from the month
	currentYear, currentMonth, _ := now.Date()
	currentLocation := now.Location()
	firstOfMonth := time.Date(currentYear, currentMonth, 1, 0, 0, 0, 0, currentLocation)
	lastOfMonth := firstOfMonth.AddDate(0, 1, -1)

	intMap := make(map[string]int)
	intMap["days_in_month"] = lastOfMonth.Day()

	rooms, err := m.DB.AllRooms()
	if err != nil {
		helpers.ServerError(w, err)
		return
	}

	data["rooms"] = rooms

	for _, x := range rooms {
		// create maps
		reservationMap := make(map[string]int)
		blockMap := make(map[string]int)

		for d := firstOfMonth; !d.After(lastOfMonth); d = d.AddDate(0, 0, 1) {
			reservationMap[d.Format("2006-01-2")] = 0
			blockMap[d.Format("2006-01-2")] = 0
		}

		// get all the restrictions for the current room
		restrictions, err := m.DB.GetRestrictionsForRoomByDate(x.ID, firstOfMonth, lastOfMonth)
		if err != nil {
			helpers.ServerError(w, err)
			return
		}

		for _, y := range restrictions {
			if y.ReservationID > 0 {
				// it's a reservation
				for d := y.StartDate; !d.After(y.EndDate); d = d.AddDate(0, 0, 1) {
					reservationMap[d.Format("2006-01-2")] = y.ReservationID
				}
			} else {
				// it's a block
				for d := y.StartDate; !d.After(y.EndDate); d = d.AddDate(0, 0, 1) {
					blockMap[d.Format("2006-01-2")] = y.ID
				}
			}
		}
		data[fmt.Sprintf("reservation_map_%d", x.ID)] = reservationMap
		data[fmt.Sprintf("block_map_%d", x.ID)] = blockMap

		m.App.Session.Put(r.Context(), fmt.Sprintf("block_map_%d", x.ID), blockMap)
	}

	render.Template(w, r, "admin-reservations-calendar.page.tmpl",
		&models.TemplateData{
			StringMap: stringMap,
			Data:      data,
			IntMap:    intMap,
		})
}

// AdminProcessReservation marks a reservation as processed
func (m *Repository) AdminProcessReservation(w http.ResponseWriter, r *http.Request) {
	id, _ := strconv.Atoi(chi.URLParam(r, "id"))
	src := chi.URLParam(r, "src")

	_ = m.DB.UpdateProcessedForReservation(id, 1)

	m.App.Session.Put(r.Context(), "flash", "Reservation marked as processed")

	http.Redirect(w, r, fmt.Sprintf("/admin/reservations-%s", src), http.StatusSeeOther)
}

// AdminDeleteReservation deletes a reservation
func (m *Repository) AdminDeleteReservation(w http.ResponseWriter, r *http.Request) {
	id, _ := strconv.Atoi(chi.URLParam(r, "id"))
	src := chi.URLParam(r, "src")

	_ = m.DB.DeleteReservation(id)

	m.App.Session.Put(r.Context(), "flash", fmt.Sprintf("Reservation %d deleted", id))

	http.Redirect(w, r, fmt.Sprintf("/admin/reservations-%s", src), http.StatusSeeOther)
}