package handler

import (
	"net/http"
	"os"
	"path/filepath"

	"github.com/gin-gonic/gin"

	"sproutworkcollect-backend/internal/service"
)

// MediaHandler serves static media files (images, videos, and downloadable assets).
type MediaHandler struct {
	workSvc     *service.WorkService
	rateLimiter *service.RateLimiter
}

// NewMediaHandler wires up a MediaHandler with its dependencies.
func NewMediaHandler(workSvc *service.WorkService, rateLimiter *service.RateLimiter) *MediaHandler {
	return &MediaHandler{workSvc: workSvc, rateLimiter: rateLimiter}
}

// ServeImage handles GET /api/image/:work_id/:filename
func (h *MediaHandler) ServeImage(c *gin.Context) {
	imgPath := filepath.Join(
		h.workSvc.WorksDir(),
		c.Param("work_id"),
		"image",
		c.Param("filename"),
	)
	if _, err := os.Stat(imgPath); os.IsNotExist(err) {
		c.JSON(http.StatusNotFound, gin.H{"error": "图片不存在"})
		return
	}
	c.File(imgPath)
}

// ServeVideo handles GET /api/video/:work_id/:filename
func (h *MediaHandler) ServeVideo(c *gin.Context) {
	videoPath := filepath.Join(
		h.workSvc.WorksDir(),
		c.Param("work_id"),
		"video",
		c.Param("filename"),
	)
	if _, err := os.Stat(videoPath); os.IsNotExist(err) {
		c.JSON(http.StatusNotFound, gin.H{"error": "视频不存在"})
		return
	}
	c.File(videoPath)
}

// DownloadFile handles GET /api/download/:work_id/:platform/:filename
func (h *MediaHandler) DownloadFile(c *gin.Context) {
	workID := c.Param("work_id")
	platform := c.Param("platform")
	filename := c.Param("filename")

	filePath := filepath.Join(h.workSvc.WorksDir(), workID, "platform", platform, filename)
	if _, err := os.Stat(filePath); os.IsNotExist(err) {
		c.JSON(http.StatusNotFound, gin.H{"error": "文件不存在"})
		return
	}

	fp := service.Fingerprint(c.ClientIP(), c.GetHeader("User-Agent"))
	if h.rateLimiter.CanPerform(fp, "download", workID) {
		_ = h.workSvc.UpdateStats(workID, "download")
	}

	c.FileAttachment(filePath, filename)
}