package handlers

import (
	"io"
	"net/http"
	"path/filepath"
	"strings"

	"game-admin/internal/config"

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

type ImageHandler struct {
	cfg *config.Config
}

func NewImageHandler(cfg *config.Config) *ImageHandler {
	return &ImageHandler{cfg: cfg}
}

func (h *ImageHandler) Upload(c *gin.Context) {
	fileHeader, err := c.FormFile("file")
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "file is required"})
		return
	}
	if fileHeader.Size == 0 {
		c.JSON(http.StatusBadRequest, gin.H{"error": "file is empty"})
		return
	}

	file, err := fileHeader.Open()
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "could not open uploaded file"})
		return
	}
	defer file.Close()

	sniff := make([]byte, 512)
	n, err := file.Read(sniff)
	if err != nil && err != io.EOF {
		c.JSON(http.StatusBadRequest, gin.H{"error": "could not read uploaded file"})
		return
	}

	contentType := http.DetectContentType(sniff[:n])
	if !strings.HasPrefix(contentType, "image/") {
		c.JSON(http.StatusBadRequest, gin.H{"error": "only image files are allowed"})
		return
	}

	ext := strings.ToLower(filepath.Ext(fileHeader.Filename))
	if ext == "" {
		ext = extensionFromContentType(contentType)
	}
	if ext == "" {
		ext = ".bin"
	}

	fileName := uuid.NewString() + ext
	relativePath := filepath.ToSlash(filepath.Join("images", fileName))
	fullPath := filepath.Join(h.cfg.UploadDir, filepath.FromSlash(relativePath))
	if err := c.SaveUploadedFile(fileHeader, fullPath); err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "could not save uploaded file"})
		return
	}

	url := strings.TrimRight(h.cfg.BaseURL, "/") + "/uploads/" + relativePath
	c.JSON(http.StatusCreated, gin.H{
		"name":         fileName,
		"path":         "/uploads/" + relativePath,
		"url":          url,
		"content_type": contentType,
	})
}

func extensionFromContentType(contentType string) string {
	switch contentType {
	case "image/jpeg":
		return ".jpg"
	case "image/png":
		return ".png"
	case "image/gif":
		return ".gif"
	case "image/webp":
		return ".webp"
	case "image/svg+xml":
		return ".svg"
	default:
		return ""
	}
}