package handler

import (
	"fmt"
	"image"
	_ "image/jpeg"
	_ "image/png"
	"net/http"
	"os"
	"path/filepath"

	"github.com/disintegration/imaging"
	"github.com/gin-gonic/gin"
	"gorm.io/gorm"

	"github.com/wangjia/jiu/backend/config"
	"github.com/wangjia/jiu/backend/internal/middleware"
	"github.com/wangjia/jiu/backend/internal/model"
)

type ShopHandler struct {
	db *gorm.DB
}

func NewShopHandler(db *gorm.DB) *ShopHandler {
	return &ShopHandler{db: db}
}

// GetInfo GET /api/v1/shop/info
func (h *ShopHandler) GetInfo(c *gin.Context) {
	shopID := middleware.GetShopID(c)
	var shop model.Shop
	if err := h.db.First(&shop, shopID).Error; err != nil {
		c.JSON(http.StatusNotFound, gin.H{"error": "shop not found"})
		return
	}
	c.JSON(http.StatusOK, shop)
}

// UpdateInfo PUT /api/v1/shop/info  (admin only)
func (h *ShopHandler) UpdateInfo(c *gin.Context) {
	shopID := middleware.GetShopID(c)

	var req struct {
		Name         string                 `json:"name"`
		Address      string                 `json:"address"`
		Phone        string                 `json:"phone"`
		ManagerName  string                 `json:"manager_name"`
		LogoURL      string                 `json:"logo_url"`
		WechatID     string                 `json:"wechat_id"`
		CustomFields map[string]interface{} `json:"custom_fields"`
	}
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		return
	}

	updates := map[string]interface{}{
		"name":         req.Name,
		"address":      req.Address,
		"phone":        req.Phone,
		"manager_name": req.ManagerName,
		"wechat_id":    req.WechatID,
	}
	if req.LogoURL != "" {
		updates["logo_url"] = req.LogoURL
	}
	// custom_fields 增量 merge：保留已有键（如其它店级配置），只覆盖本次传入的键。
	if req.CustomFields != nil {
		var cur model.Shop
		h.db.Select("custom_fields").Where("id = ?", shopID).First(&cur)
		merged := model.JSON{}
		for k, v := range cur.CustomFields {
			merged[k] = v
		}
		for k, v := range req.CustomFields {
			merged[k] = v
		}
		updates["custom_fields"] = merged
	}
	if err := h.db.Model(&model.Shop{}).Where("id = ?", shopID).Updates(updates).Error; err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	var shop model.Shop
	h.db.First(&shop, shopID)
	c.JSON(http.StatusOK, shop)
}

// UploadLogo POST /api/v1/shop/logo  (admin only)
func (h *ShopHandler) UploadLogo(c *gin.Context) {
	shopID := middleware.GetShopID(c)

	if err := c.Request.ParseMultipartForm(2 << 20); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "文件超过 2MB 限制"})
		return
	}
	file, _, err := c.Request.FormFile("file")
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "请上传文件（field: file）"})
		return
	}
	defer file.Close()

	img, _, err := image.Decode(file)
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "仅支持 JPEG/PNG 图片"})
		return
	}

	// 裁剪为正方形后缩放到 256×256
	resized := imaging.Fill(img, 256, 256, imaging.Center, imaging.Lanczos)

	subdir := filepath.Join(config.C.Storage.UploadDir, "shops", fmt.Sprintf("%d", shopID))
	if err := os.MkdirAll(subdir, 0755); err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "存储目录创建失败"})
		return
	}
	fullPath := filepath.Join(subdir, "logo.jpg")

	if err := imaging.Save(resized, fullPath, imaging.JPEGQuality(90)); err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "图片保存失败"})
		return
	}

	logoURL := fmt.Sprintf("/images/shops/%d/logo.jpg", shopID)
	if err := h.db.Model(&model.Shop{}).Where("id = ?", shopID).Update("logo_url", logoURL).Error; err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusOK, gin.H{"logo_url": logoURL})
}