package handlers

import (
	"crypto/sha256"
	"encoding/hex"
	"io"
	"net/http"
	"os"
	"path/filepath"
	"strconv"
	"strings"
	"time"

	"github.com/gin-gonic/gin"
	"github.com/google/uuid"
	"gorm.io/gorm"

	"everypublish/server/internal/api/response"
	"everypublish/server/internal/config"
	"everypublish/server/internal/models"
)

// MaterialHandler 素材处理器（服务器本地盘一期；StorageDriver 二期 OSS）
type MaterialHandler struct {
	DB  *gorm.DB
	Cfg *config.Config
}

// List 素材列表（分页 + 筛选）
func (h *MaterialHandler) List(c *gin.Context) {
	page, _ := strconv.Atoi(c.DefaultQuery("page", "1"))
	size, _ := strconv.Atoi(c.DefaultQuery("size", "20"))
	if page < 1 {
		page = 1
	}
	if size < 1 || size > 100 {
		size = 20
	}
	q := h.DB.Model(&models.Material{}).Where("workspace_id = ? and status = ?", c.GetUint64("wsid"), "ready")
	if k := c.Query("kind"); k != "" {
		q = q.Where("kind = ?", k)
	}
	if g := c.Query("group"); g != "" {
		q = q.Where("`group` = ?", g)
	}
	var total int64
	q.Count(&total)
	var list []models.Material
	q.Order("id desc").Offset((page - 1) * size).Limit(size).Find(&list)
	response.OK(c, gin.H{"list": list, "total": total, "page": page, "size": size})
}

// Upload multipart 上传：流式计算 sha256，同工作区按 sha256 去重
func (h *MaterialHandler) Upload(c *gin.Context) {
	if h.Cfg.MaxUploadBytes > 0 {
		c.Request.Body = http.MaxBytesReader(c.Writer, c.Request.Body, h.Cfg.MaxUploadBytes)
	}
	file, header, err := c.Request.FormFile("file")
	if err != nil {
		response.Fail(c, http.StatusBadRequest, 1001, "文件过大或缺少文件字段 file")
		return
	}
	defer file.Close()
	wsid := c.GetUint64("wsid")
	dir := filepath.Join(h.Cfg.StorageDir, itoa(wsid))
	if err = os.MkdirAll(dir, 0o755); err != nil {
		response.Fail(c, http.StatusInternalServerError, 5000, "存储初始化失败")
		return
	}
	ext := strings.ToLower(filepath.Ext(header.Filename))
	if ext == "" || len(ext) > 16 {
		ext = ".bin"
	}
	key := filepath.Join(itoa(wsid), uuid.NewString()+ext)
	abspath := filepath.Join(h.Cfg.StorageDir, key)
	dst, err := os.Create(abspath)
	if err != nil {
		response.Fail(c, http.StatusInternalServerError, 5000, "写盘失败")
		return
	}
	hasher := sha256.New()
	size, err := io.Copy(io.MultiWriter(dst, hasher), file)
	dst.Close()
	if err != nil {
		_ = os.Remove(abspath)
		response.Fail(c, http.StatusInternalServerError, 5000, "写入失败")
		return
	}
	sum := hex.EncodeToString(hasher.Sum(nil))
	// 去重：同工作区同 sha256 直接复用
	var existing models.Material
	if err = h.DB.Where("workspace_id = ? and sha256 = ? and status = ?", wsid, sum, "ready").First(&existing).Error; err == nil {
		_ = os.Remove(abspath)
		response.OK(c, gin.H{"material": existing, "dedup": true})
		return
	}
	kind := "image"
	contentType := strings.ToLower(header.Header.Get("Content-Type"))
	if strings.HasPrefix(contentType, "video/") || isVideoExtension(ext) {
		kind = "video"
	}
	group := strings.TrimSpace(c.PostForm("group"))
	tags := strings.TrimSpace(c.PostForm("tags"))
	if tags == "" {
		tags = "[]"
	}
	material := models.Material{
		WorkspaceID: wsid,
		Name:        header.Filename,
		Kind:        kind,
		Size:        size,
		SHA256:      sum,
		Mime:        header.Header.Get("Content-Type"),
		StorageKey:  key,
		Group:       group,
		Tags:        tags,
		Status:      "ready",
		CreatedBy:   c.GetUint64("uid"),
	}
	if err = h.DB.Create(&material).Error; err != nil {
		_ = os.Remove(abspath)
		response.Fail(c, http.StatusInternalServerError, 5000, "入库失败")
		return
	}
	response.Audit(c, "material.upload", "material:"+itoa(material.ID), gin.H{"name": header.Filename, "size": size})
	response.OK(c, gin.H{"material": material, "dedup": false})
}

func isVideoExtension(ext string) bool {
	switch strings.ToLower(ext) {
	case ".mp4", ".mov", ".avi", ".mkv", ".m4v", ".webm", ".flv", ".wmv":
		return true
	default:
		return false
	}
}

// URL 生成签名直链（10 分钟一次性）
func (h *MaterialHandler) URL(c *gin.Context) {
	id, err := strconv.ParseUint(c.Param("id"), 10, 64)
	if err != nil {
		response.Fail(c, http.StatusBadRequest, 1001, "参数不合法")
		return
	}
	var material models.Material
	if err = h.DB.Where("id = ? and workspace_id = ?", id, c.GetUint64("wsid")).First(&material).Error; err != nil {
		response.Fail(c, http.StatusNotFound, 1004, "素材不存在")
		return
	}
	token := models.TransferToken{
		MaterialID: material.ID,
		Token:      uuid.NewString(),
		ExpiresAt:  time.Now().Add(10 * time.Minute),
	}
	if err = h.DB.Create(&token).Error; err != nil {
		response.Fail(c, http.StatusInternalServerError, 5000, "生成链接失败")
		return
	}
	response.OK(c, gin.H{"url": h.Cfg.BaseURL + "/api/v1/files/" + token.Token, "expiresAt": token.ExpiresAt})
}

// ServeFile 凭 token 取文件（一次性，10 分钟有效）
func (h *MaterialHandler) ServeFile(c *gin.Context) {
	tokenStr := c.Param("token")
	var token models.TransferToken
	if err := h.DB.Where("token = ?", tokenStr).First(&token).Error; err != nil {
		response.Fail(c, http.StatusNotFound, 1004, "链接无效")
		return
	}
	if time.Now().After(token.ExpiresAt) {
		h.DB.Delete(&token)
		response.Fail(c, http.StatusGone, 3004, "链接已过期")
		return
	}
	var material models.Material
	if err := h.DB.First(&material, token.MaterialID).Error; err != nil {
		response.Fail(c, http.StatusNotFound, 1004, "素材不存在")
		return
	}
	// 一次性：取用即吊销
	_ = h.DB.Delete(&token).Error
	abspath := filepath.Join(h.Cfg.StorageDir, material.StorageKey)
	clean := filepath.Clean(abspath)
	root := filepath.Clean(h.Cfg.StorageDir) + string(os.PathSeparator)
	if !strings.HasPrefix(clean, root) {
		response.Fail(c, http.StatusForbidden, 1003, "非法路径")
		return
	}
	if c.Query("inline") == "1" {
		c.File(abspath)
		return
	}
	c.FileAttachment(abspath, material.Name)
}

// Delete 删除素材（含文件）
func (h *MaterialHandler) Delete(c *gin.Context) {
	id, err := strconv.ParseUint(c.Param("id"), 10, 64)
	if err != nil {
		response.Fail(c, http.StatusBadRequest, 1001, "参数不合法")
		return
	}
	var material models.Material
	if err = h.DB.Where("id = ? and workspace_id = ?", id, c.GetUint64("wsid")).First(&material).Error; err != nil {
		response.Fail(c, http.StatusNotFound, 1004, "素材不存在")
		return
	}
	abspath := filepath.Join(h.Cfg.StorageDir, material.StorageKey)
	_ = os.Remove(abspath)
	if err = h.DB.Delete(&material).Error; err != nil {
		response.Fail(c, http.StatusInternalServerError, 5000, "删除失败")
		return
	}
	response.Audit(c, "material.delete", "material:"+itoa(id), nil)
	response.OK(c, nil)
}