package storage

import (
	"fmt"
	"net/http"

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

var defaultAllowedTypes = map[string]bool{
	"image/jpeg": true,
	"image/png":  true,
	"image/gif":  true,
	"image/webp": true,
	"image/svg+xml": true,
	"application/pdf": true,
}

var defaultMaxSize int64 = 10 << 20

type UploadConfig struct {
	FieldName    string
	MaxSize      int64
	AllowedTypes map[string]bool
}

func UploadMiddleware(cfg UploadConfig) gin.HandlerFunc {
	if cfg.FieldName == "" {
		cfg.FieldName = "file"
	}
	if cfg.MaxSize <= 0 {
		cfg.MaxSize = defaultMaxSize
	}
	if cfg.AllowedTypes == nil {
		cfg.AllowedTypes = defaultAllowedTypes
	}

	return func(c *gin.Context) {
		file, header, err := c.Request.FormFile(cfg.FieldName)
		if err != nil {
			c.JSON(http.StatusBadRequest, gin.H{"error": "file field required"})
			c.Abort()
			return
		}

		if header.Size > cfg.MaxSize {
			file.Close()
			c.JSON(http.StatusRequestEntityTooLarge, gin.H{"error": fmt.Sprintf("file too large (max %d bytes)", cfg.MaxSize)})
			c.Abort()
			return
		}

		contentType := header.Header.Get("Content-Type")
		if len(cfg.AllowedTypes) > 0 && !cfg.AllowedTypes[contentType] {
			file.Close()
			c.JSON(http.StatusUnsupportedMediaType, gin.H{"error": fmt.Sprintf("file type not allowed: %s", contentType)})
			c.Abort()
			return
		}

		c.Set("upload_file", &File{
			Name:        header.Filename,
			ContentType: contentType,
			Size:        header.Size,
			Reader:      file,
		})

		c.Next()
		file.Close()
	}
}