package controllers

import (
	"fmt"
	"strconv"
	"net/http"
  "crypto/rand"
  "encoding/hex"

	"github.com/gin-gonic/gin"

	"example.com/gin/test/models"
	//"example.com/gin/test/services"
	"example.com/gin/test/repositories"
)

type CartItemController interface {
	//CRUDController
	CartItemView(*gin.Context)
	AddItemHandler(*gin.Context)
	DeleteItemHandler(*gin.Context)
	EditItemHandler(*gin.Context)
	CheckoutView(*gin.Context)
}

type cartItemController struct {}

func NewCartItemController() CartItemController {
	return &cartItemController{}
}

func generateSessionId() string {
    bytes := make([]byte, 16) // 16 bytes = 128 bits
    _, err := rand.Read(bytes)
    if err != nil {
        panic("failed to generate session ID")
    }
    return hex.EncodeToString(bytes)
}

func GetSessionId(ctx *gin.Context) string {
	sessionId, err := ctx.Cookie("session_id")

	if err != nil {
		sessionId = generateSessionId()
		ctx.SetCookie("session_id", sessionId, 3600, "/", "", false, true)
	}

	return sessionId
}

func (rc *cartItemController) NewCartItemFromForm(ctx *gin.Context) (models.CartItem, error) {
	sessionId := GetSessionId(ctx)
	shopItemIdStr := ctx.PostForm("ShopItemId")
	shopItemId, err := strconv.Atoi(shopItemIdStr)
	itemVariantIdStr := ctx.PostForm("ItemVariantId")
	itemVariantId, err := strconv.Atoi(itemVariantIdStr)

	if err != nil {
		return models.CartItem{}, err
	}

	quantity := 1

	shopItem, err := repositories.ShopItems.GetById(shopItemIdStr)

	if err != nil {
		return models.CartItem{}, err
	}

	itemVariant, err := repositories.ShopItems.GetVariantById(itemVariantIdStr)

	cartItem := models.CartItem{
		SessionId: sessionId,
		ShopItemId: uint(shopItemId),
		ShopItem: shopItem,
		ItemVariantId: uint(itemVariantId),
		ItemVariant: itemVariant,
		Quantity: quantity,
	}

	return cartItem, nil
}


func (rc *cartItemController) Create(c *gin.Context) {
	cartItem, err := rc.NewCartItemFromForm(c)

	if err != nil {
		ReplyError(c, fmt.Errorf("cartItem creation failed: %s", err))
		return
	}

	_, err = repositories.CartItems.Create(cartItem)

	if err != nil {
		ReplyError(c, fmt.Errorf("cartItem creation failed: %s", err))
		return
	}

	ReplyOK(c, "cartItem was created")
}


func (rc *cartItemController) Update(c *gin.Context) {
	cartItem, err := rc.NewCartItemFromForm(c)

	if err != nil {
		ReplyError(c, err)
		return
	}

	_, err = repositories.CartItems.Update(cartItem)

	if err != nil {
		ReplyError(c, fmt.Errorf("cartItem creation failed: %s", err))
		return
	}

	ReplyOK(c, "cartItem was updated")
}

//func (rc *cartItemController) Delete(c *gin.Context) {
//	err := repositories.CartItems.DeleteBySessionId(c.Param("id"))
//
//	if err != nil {
//		ReplyError(c, fmt.Errorf("cartItem deletion failed: %s", err))
//		return
//	}
//
//	ReplyOK(c, "cartItem was deleted")
//}

func (rc *cartItemController) CartItemView(c *gin.Context) {
	//sessionId := GetSessionId(c)

	//cartItems, err := repositories.CartItems.GetAllBySession(sessionId)
	cartItems, err := repositories.CartItems.GetAll()

	if err != nil {
		c.HTML(http.StatusBadRequest, "cart.html", gin.H{ "data": gin.H{ "error": err } })
	}

	priceTotal := 0.0
	for _, cartItem := range cartItems {
		priceTotal += (float64(cartItem.Quantity) * cartItem.ItemVariant.Price)
	}

	fmt.Println("PRICE TOTAL", priceTotal)

	data := CreateSessionData(c, gin.H{
		"cartItems": cartItems,
		"priceTotal": fmt.Sprintf("%.2f", priceTotal), //round 2 decimals
	})

	c.HTML(http.StatusOK, "cart.html", data)
}

func (rc *cartItemController) AddItemHandler(c *gin.Context) {
	cartItem, err := rc.NewCartItemFromForm(c)

	if err != nil {
		fmt.Println(err)
		c.HTML(http.StatusBadRequest, "error.html", gin.H{ "error": err })
		return
	}

	_, err = repositories.CartItems.Create(cartItem)
	if err != nil {
		data := CreateSessionData(c, gin.H{
			"error": err,
			"success": "",
		})

		c.HTML(http.StatusOK, "cart.html", data)
		return
	}

	rc.CartItemView(c)
}

func (rc *cartItemController) DeleteItemHandler(c *gin.Context) {
	err := repositories.CartItems.DeleteById(c.PostForm("id"))

	if err != nil {
		fmt.Println(err)
		data := CreateSessionData(c, gin.H{
			"error": err,
			"success": "",
		})

		c.HTML(http.StatusOK, "index.html", data)
	}

	rc.CartItemView(c)
}

func (rc *cartItemController) EditItemHandler(c *gin.Context) {
	cartItemId := c.PostForm("id")
	cartItem, err := repositories.CartItems.GetById(cartItemId)

	if err != nil {
		fmt.Println(err)
		rc.CartItemView(c)
		return
	}

	action := c.PostForm("action")

	if action == "increase" {
		cartItem.Quantity += 1
	}

	if action == "decrease" {
		cartItem.Quantity -= 1

		if cartItem.Quantity == 0 {
			cartItem.Quantity = 1
		}
	}

	_, err = repositories.CartItems.Update(cartItem)

	if err != nil {
		fmt.Println(err)
	}

	rc.CartItemView(c)
}

func (rc *cartItemController) CheckoutView(c *gin.Context) {
	c.HTML(http.StatusOK, "checkout.html", gin.H{})
}