package handlers

import (
	"net/http"
	"strconv"

	"shop.tonybtw.com/internal/lib"
	"shop.tonybtw.com/internal/models"
	"shop.tonybtw.com/internal/views"
)

type Cart_Handler struct {
	ctx *lib.App_Context
}

func New_Cart_Handler(ctx *lib.App_Context) *Cart_Handler {
	return &Cart_Handler{ctx: ctx}
}

func (h *Cart_Handler) Show_Cart(w http.ResponseWriter, r *http.Request) {
	session_id := lib.Get_Session_ID(r)
	cart_json := h.ctx.Session_Store.Get_Cart(session_id)
	cart, _ := models.Parse_Cart(cart_json)

	items, err := models.Get_Cart_Items_With_Details(h.ctx.DB, cart)
	if err != nil {
		http.Error(w, "Failed to load cart", http.StatusInternalServerError)
		return
	}

	total := models.Get_Cart_Total(items)
	cart_count := models.Count_Cart_Items(cart)

	views.Cart(items, total, cart_count).Render(r.Context(), w)
}

func (h *Cart_Handler) Add_Item(w http.ResponseWriter, r *http.Request) {
	if err := r.ParseForm(); err != nil {
		http.Error(w, "Invalid form", http.StatusBadRequest)
		return
	}

	product_id, _ := strconv.Atoi(r.FormValue("product_id"))
	variant_id, _ := strconv.Atoi(r.FormValue("variant_id"))
	quantity, _ := strconv.Atoi(r.FormValue("quantity"))

	if quantity < 1 {
		quantity = 1
	}

	session_id := lib.Get_Or_Create_Session_ID(w, r)
	cart_json := h.ctx.Session_Store.Get_Cart(session_id)
	cart, _ := models.Parse_Cart(cart_json)

	cart = models.Add_To_Cart(cart, product_id, variant_id, quantity)

	updated_cart_json, _ := models.Serialize_Cart(cart)
	h.ctx.Session_Store.Set_Cart(session_id, updated_cart_json)

	cart_count := models.Count_Cart_Items(cart)

	if lib.Is_HTMX_Request(r) {
		views.Cart_Widget(cart_count).Render(r.Context(), w)
		return
	}

	referer := r.Header.Get("Referer")
	if referer == "" {
		referer = "/"
	}
	lib.Redirect(w, r, referer)
}

func (h *Cart_Handler) Update_Item(w http.ResponseWriter, r *http.Request) {
	if err := r.ParseForm(); err != nil {
		http.Error(w, "Invalid form", http.StatusBadRequest)
		return
	}

	product_id, _ := strconv.Atoi(r.FormValue("product_id"))
	variant_id, _ := strconv.Atoi(r.FormValue("variant_id"))
	quantity, _ := strconv.Atoi(r.FormValue("quantity"))

	session_id := lib.Get_Session_ID(r)
	cart_json := h.ctx.Session_Store.Get_Cart(session_id)
	cart, _ := models.Parse_Cart(cart_json)

	if quantity == 0 {
		cart = models.Remove_From_Cart(cart, product_id, variant_id)
	} else {
		cart = models.Update_Cart_Quantity(cart, product_id, variant_id, quantity)
	}

	updated_cart_json, _ := models.Serialize_Cart(cart)
	h.ctx.Session_Store.Set_Cart(session_id, updated_cart_json)

	items, err := models.Get_Cart_Items_With_Details(h.ctx.DB, cart)
	if err != nil {
		http.Error(w, "Failed to load cart", http.StatusInternalServerError)
		return
	}

	if lib.Is_HTMX_Request(r) {
		views.Cart_Items(items).Render(r.Context(), w)
		return
	}

	lib.Redirect(w, r, "/cart")
}

func (h *Cart_Handler) Remove_Item(w http.ResponseWriter, r *http.Request) {
	if err := r.ParseForm(); err != nil {
		http.Error(w, "Invalid form", http.StatusBadRequest)
		return
	}

	product_id, _ := strconv.Atoi(r.FormValue("product_id"))
	variant_id, _ := strconv.Atoi(r.FormValue("variant_id"))

	session_id := lib.Get_Session_ID(r)
	cart_json := h.ctx.Session_Store.Get_Cart(session_id)
	cart, _ := models.Parse_Cart(cart_json)

	cart = models.Remove_From_Cart(cart, product_id, variant_id)

	updated_cart_json, _ := models.Serialize_Cart(cart)
	h.ctx.Session_Store.Set_Cart(session_id, updated_cart_json)

	items, err := models.Get_Cart_Items_With_Details(h.ctx.DB, cart)
	if err != nil {
		http.Error(w, "Failed to load cart", http.StatusInternalServerError)
		return
	}

	if lib.Is_HTMX_Request(r) {
		views.Cart_Items(items).Render(r.Context(), w)
		return
	}

	lib.Redirect(w, r, "/cart")
}