package user

import (
	"errors"
	"fmt"
	"image"
	_ "image/gif"
	_ "image/jpeg"
	"image/png"
	"net/http"
	"os"
	"path/filepath"
	"strconv"
	"time"

	"cardverse/internal/pkg/response"
	"cardverse/internal/pkg/validator"

	"github.com/gin-gonic/gin"
)

type Handler struct {
	service Service
}

func NewHandler(service Service) *Handler {
	return &Handler{service: service}
}

func (h *Handler) GetProfile(c *gin.Context) {
	userIDVal, exists := c.Get("user_id")
	if !exists {
		response.Error(c, http.StatusUnauthorized, "autentikasi diperlukan", nil)
		return
	}
	userID := userIDVal.(uint)

	u, err := h.service.GetByID(userID)
	if err != nil {
		response.Error(c, http.StatusNotFound, err.Error(), nil)
		return
	}

	response.Success(c, http.StatusOK, "berhasil mengambil profil user", ToUserResponse(*u))
}

func (h *Handler) UpdateProfile(c *gin.Context) {
	userIDVal, exists := c.Get("user_id")
	if !exists {
		response.Error(c, http.StatusUnauthorized, "autentikasi diperlukan", nil)
		return
	}
	userID := userIDVal.(uint)

	var req UpdateProfileRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		response.Error(c, http.StatusBadRequest, "input tidak valid", validator.TranslateError(err))
		return
	}

	updatedUser, err := h.service.UpdateProfile(userID, req)
	if err != nil {
		response.Error(c, http.StatusInternalServerError, "gagal mengupdate profil", err.Error())
		return
	}

	response.Success(c, http.StatusOK, "profil berhasil diupdate", ToUserResponse(*updatedUser))
}

func (h *Handler) UploadAvatar(c *gin.Context) {
	userIDVal, exists := c.Get("user_id")
	if !exists {
		response.Error(c, http.StatusUnauthorized, "autentikasi diperlukan", nil)
		return
	}
	userID := userIDVal.(uint)

	fileHeader, err := c.FormFile("avatar")
	if err != nil {
		response.Error(c, http.StatusBadRequest, "file avatar wajib diunggah (form field: avatar)", nil)
		return
	}

	// Batas ukuran file 5 MB
	if fileHeader.Size > 5*1024*1024 {
		response.Error(c, http.StatusBadRequest, "ukuran file maksimal 5MB", nil)
		return
	}

	srcFile, err := fileHeader.Open()
	if err != nil {
		response.Error(c, http.StatusInternalServerError, "gagal membaca file avatar", err.Error())
		return
	}
	defer srcFile.Close()

	// Dekode gambar (support JPG, JPEG, PNG, GIF)
	img, _, err := image.Decode(srcFile)
	if err != nil {
		response.Error(c, http.StatusBadRequest, "file yang diunggah bukan format gambar yang valid", err.Error())
		return
	}

	// Simpan ke direktori: ./public/images/avatars
	uploadDir := "./public/images/avatars"
	if err := os.MkdirAll(uploadDir, os.ModePerm); err != nil {
		response.Error(c, http.StatusInternalServerError, "gagal membuat direktori penyimpanan avatar", err.Error())
		return
	}

	filename := fmt.Sprintf("avatar_%d_%d.png", userID, time.Now().UnixNano())
	filepathDst := filepath.Join(uploadDir, filename)

	out, err := os.Create(filepathDst)
	if err != nil {
		response.Error(c, http.StatusInternalServerError, "gagal membuat file avatar", err.Error())
		return
	}
	defer out.Close()

	// Encode & kompresi ke format PNG
	encoder := png.Encoder{CompressionLevel: png.BestCompression}
	if err := encoder.Encode(out, img); err != nil {
		response.Error(c, http.StatusInternalServerError, "gagal mengompresi gambar ke format PNG", err.Error())
		return
	}

	avatarURL := fmt.Sprintf("/images/avatars/%s", filename)
	updatedUser, err := h.service.UpdateAvatar(userID, avatarURL)
	if err != nil {
		response.Error(c, http.StatusInternalServerError, "gagal memperbarui avatar user", err.Error())
		return
	}

	response.Success(c, http.StatusOK, "avatar berhasil diunggah", ToUserResponse(*updatedUser))
}

func (h *Handler) Create(c *gin.Context) {
	creatorID := getContextUserID(c)

	var req CreateUserRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		response.Error(c, http.StatusBadRequest, "input tidak valid", validator.TranslateError(err))
		return
	}

	newUser, err := h.service.Create(creatorID, req)
	if err != nil {
		if errors.Is(err, ErrEmailTaken) {
			response.Error(c, http.StatusConflict, err.Error(), nil)
			return
		}
		if errors.Is(err, ErrForbiddenRoleCreation) {
			response.Error(c, http.StatusForbidden, err.Error(), nil)
			return
		}
		response.Error(c, http.StatusInternalServerError, "gagal membuat user", err.Error())
		return
	}

	response.Success(c, http.StatusCreated, "user berhasil dibuat", ToUserResponse(*newUser))
}

func (h *Handler) GetAll(c *gin.Context) {
	var query ListUserQuery
	if err := c.ShouldBindQuery(&query); err != nil {
		response.Error(c, http.StatusBadRequest, "query parameter tidak valid", validator.TranslateError(err))
		return
	}

	users, total, err := h.service.GetAllPaginated(query)
	if err != nil {
		response.Error(c, http.StatusInternalServerError, "gagal mengambil data user", err.Error())
		return
	}

	pagination := response.NewPagination(query.Page, query.Limit, total)
	response.SuccessWithPagination(c, http.StatusOK, "berhasil mengambil data user", ToUserResponseList(users), pagination)
}

func (h *Handler) GetByID(c *gin.Context) {
	id, err := parseID(c)
	if err != nil {
		response.Error(c, http.StatusBadRequest, "id tidak valid", []validator.FieldError{
			{Field: "id", Message: "id harus berupa angka"},
		})
		return
	}

	u, err := h.service.GetByID(id)
	if err != nil {
		response.Error(c, http.StatusNotFound, err.Error(), nil)
		return
	}

	response.Success(c, http.StatusOK, "berhasil mengambil data user", ToUserResponse(*u))
}

func (h *Handler) Update(c *gin.Context) {
	modifierID := getContextUserIDValue(c)

	id, err := parseID(c)
	if err != nil {
		response.Error(c, http.StatusBadRequest, "id tidak valid", []validator.FieldError{
			{Field: "id", Message: "id harus berupa angka"},
		})
		return
	}

	var req UpdateUserRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		response.Error(c, http.StatusBadRequest, "input tidak valid", validator.TranslateError(err))
		return
	}

	updatedUser, err := h.service.Update(modifierID, id, req)
	if err != nil {
		if errors.Is(err, ErrEmailTaken) {
			response.Error(c, http.StatusConflict, err.Error(), nil)
			return
		}
		if errors.Is(err, ErrForbiddenRoleCreation) {
			response.Error(c, http.StatusForbidden, err.Error(), nil)
			return
		}
		response.Error(c, http.StatusNotFound, err.Error(), nil)
		return
	}

	response.Success(c, http.StatusOK, "user berhasil diupdate", ToUserResponse(*updatedUser))
}

func (h *Handler) Suspend(c *gin.Context) {
	modifierID := getContextUserIDValue(c)

	id, err := parseID(c)
	if err != nil {
		response.Error(c, http.StatusBadRequest, "id tidak valid", []validator.FieldError{
			{Field: "id", Message: "id harus berupa angka"},
		})
		return
	}

	updatedUser, err := h.service.SuspendUser(modifierID, id)
	if err != nil {
		response.Error(c, http.StatusNotFound, err.Error(), nil)
		return
	}

	response.Success(c, http.StatusOK, "user berhasil disuspensi", ToUserResponse(*updatedUser))
}

func (h *Handler) Unsuspend(c *gin.Context) {
	modifierID := getContextUserIDValue(c)

	id, err := parseID(c)
	if err != nil {
		response.Error(c, http.StatusBadRequest, "id tidak valid", []validator.FieldError{
			{Field: "id", Message: "id harus berupa angka"},
		})
		return
	}

	updatedUser, err := h.service.UnsuspendUser(modifierID, id)
	if err != nil {
		response.Error(c, http.StatusNotFound, err.Error(), nil)
		return
	}

	response.Success(c, http.StatusOK, "suspensi user berhasil dicabut", ToUserResponse(*updatedUser))
}

func (h *Handler) Delete(c *gin.Context) {
	id, err := parseID(c)
	if err != nil {
		response.Error(c, http.StatusBadRequest, "id tidak valid", []validator.FieldError{
			{Field: "id", Message: "id harus berupa angka"},
		})
		return
	}

	if err := h.service.Delete(id); err != nil {
		response.Error(c, http.StatusNotFound, err.Error(), nil)
		return
	}

	response.Success(c, http.StatusOK, "user berhasil dihapus", nil)
}

func parseID(c *gin.Context) (uint, error) {
	idParam := c.Param("id")
	id, err := strconv.ParseUint(idParam, 10, 64)
	if err != nil {
		return 0, err
	}
	return uint(id), nil
}

func getContextUserID(c *gin.Context) *uint {
	if val, exists := c.Get("user_id"); exists {
		if userID, ok := val.(uint); ok {
			return &userID
		}
	}
	return nil
}

func getContextUserIDValue(c *gin.Context) uint {
	if val, exists := c.Get("user_id"); exists {
		if userID, ok := val.(uint); ok {
			return userID
		}
	}
	return 0
}