package listing

import (
	"errors"
	"strconv"

	"hfb_jysh/backend/pkg/response"

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

func parseListingIDParam(c *gin.Context) (uint64, bool) {
	id, err := strconv.ParseUint(c.Param("listingId"), 10, 64)
	if err != nil || id == 0 {
		response.BadRequest(c, "商品 ID 不正确")
		return 0, false
	}
	return id, true
}

func writeCollectionError(c *gin.Context, err error) {
	switch {
	case errors.Is(err, ErrCollectionKindInvalid):
		response.BadRequest(c, "足迹类型不正确")
	case errors.Is(err, gorm.ErrRecordNotFound):
		response.NotFound(c, "商品不存在或已删除")
	default:
		writeListingError(c, err)
	}
}

func (h *Handler) ListCollections(c *gin.Context) {
	userID, ok := currentUserID(c)
	if !ok {
		response.Unauthorized(c, "缺少用户上下文")
		return
	}
	kind := c.DefaultQuery("kind", CollectionKindHistory)
	result, err := h.service.ListCollections(c.Request.Context(), userID, kind)
	if err != nil {
		writeCollectionError(c, err)
		return
	}
	response.OK(c, result)
}

type collectionBody struct {
	ListingID uint64 `json:"listing_id" binding:"required"`
}

func (h *Handler) RecordCollectionView(c *gin.Context) {
	userID, ok := currentUserID(c)
	if !ok {
		response.Unauthorized(c, "缺少用户上下文")
		return
	}
	var req collectionBody
	if err := c.ShouldBindJSON(&req); err != nil {
		response.BadRequest(c, "商品 ID 不正确")
		return
	}
	if err := h.service.RecordCollectionView(c.Request.Context(), userID, req.ListingID); err != nil {
		writeCollectionError(c, err)
		return
	}
	response.OK(c, gin.H{"recorded": true})
}

func (h *Handler) AddCollectionFavorite(c *gin.Context) {
	userID, ok := currentUserID(c)
	if !ok {
		response.Unauthorized(c, "缺少用户上下文")
		return
	}
	var req collectionBody
	if err := c.ShouldBindJSON(&req); err != nil {
		response.BadRequest(c, "商品 ID 不正确")
		return
	}
	if err := h.service.AddCollectionFavorite(c.Request.Context(), userID, req.ListingID); err != nil {
		writeCollectionError(c, err)
		return
	}
	response.OK(c, gin.H{"favorited": true})
}

func (h *Handler) RemoveCollectionFavorite(c *gin.Context) {
	userID, ok := currentUserID(c)
	if !ok {
		response.Unauthorized(c, "缺少用户上下文")
		return
	}
	listingID, ok := parseListingIDParam(c)
	if !ok {
		return
	}
	if err := h.service.RemoveCollectionFavorite(c.Request.Context(), userID, listingID); err != nil {
		writeCollectionError(c, err)
		return
	}
	response.OK(c, gin.H{"deleted": true})
}

func (h *Handler) RemoveCollectionHistory(c *gin.Context) {
	userID, ok := currentUserID(c)
	if !ok {
		response.Unauthorized(c, "缺少用户上下文")
		return
	}
	listingID, ok := parseListingIDParam(c)
	if !ok {
		return
	}
	if err := h.service.RemoveCollectionHistory(c.Request.Context(), userID, listingID); err != nil {
		writeCollectionError(c, err)
		return
	}
	response.OK(c, gin.H{"deleted": true})
}

func (h *Handler) ClearCollectionHistory(c *gin.Context) {
	userID, ok := currentUserID(c)
	if !ok {
		response.Unauthorized(c, "缺少用户上下文")
		return
	}
	if err := h.service.ClearCollectionHistory(c.Request.Context(), userID); err != nil {
		writeCollectionError(c, err)
		return
	}
	response.OK(c, gin.H{"cleared": true})
}