package mohong

import (
	"encoding/json"
	"fmt"
	"strings"

	"hfb_sys/backend/internal/model"
	"hfb_sys/backend/pkg/money"
)

func toProductDTO(row model.MohongProduct, includeAdminFields bool) ProductDTO {
	images := decodeStringList(row.ImageURLs)
	dto := ProductDTO{
		ID:                row.ID,
		CategoryID:        row.CategoryID,
		Title:             row.Title,
		CoverURL:          row.CoverURL,
		ImageURLs:         images,
		Description:       row.Description,
		PriceCent:         row.PriceCent,
		Price:             money.Format(row.PriceCent),
		OriginalPriceCent: row.OriginalPriceCent,
		Unit:              row.Unit,
		Stock:             row.Stock,
		SortOrder:         row.SortOrder,
		Status:            row.Status,
		CreatedAt:         row.CreatedAt,
		UpdatedAt:         row.UpdatedAt,
	}
	if row.OriginalPriceCent > 0 {
		dto.OriginalPrice = money.Format(row.OriginalPriceCent)
	}
	if includeAdminFields {
		dto.QrcodeImageURL = row.QrcodeImageURL
	}
	return dto
}

func toProductDTOWithCategory(row model.MohongProduct, categoryName string, includeAdminFields bool) ProductDTO {
	dto := toProductDTO(row, includeAdminFields)
	dto.CategoryName = categoryName
	return dto
}

func toOrderDTO(row model.MohongOrder, snap productSnapshot, items []orderItemSnapshot, buyerNickname, buyerPhone string, includeAdmin bool) OrderDTO {
	if len(items) == 0 {
		items = decodeOrderItems(row)
	}
	title := snap.Title
	cover := snap.CoverURL
	unit := snap.Unit
	if title == "" && len(items) > 0 {
		title = items[0].Title
	}
	if cover == "" && len(items) > 0 {
		cover = items[0].CoverURL
	}
	if unit == "" && len(items) > 0 {
		unit = items[0].Unit
	}
	if len(items) > 1 && title != "" {
		title = fmt.Sprintf("%s 等%d种", title, len(items))
	}
	itemDTOs := make([]OrderItemDTO, 0, len(items))
	for _, item := range items {
		lineAmount := item.PriceCent * int64(item.Quantity)
		itemDTOs = append(itemDTOs, OrderItemDTO{
			ProductID:     item.ID,
			Title:         item.Title,
			CoverURL:      item.CoverURL,
			Unit:          item.Unit,
			Quantity:      item.Quantity,
			UnitPriceCent: item.PriceCent,
			UnitPrice:     money.Format(item.PriceCent),
			AmountCent:    lineAmount,
			Amount:        money.Format(lineAmount),
		})
	}
	dto := OrderDTO{
		ID:                row.ID,
		OrderNo:           row.OrderNo,
		UserID:            row.UserID,
		ProductID:         row.ProductID,
		Quantity:          row.Quantity,
		UnitPriceCent:     row.UnitPriceCent,
		UnitPrice:         money.Format(row.UnitPriceCent),
		AmountCent:        row.AmountCent,
		Amount:            money.Format(row.AmountCent),
		Status:            row.Status,
		ProductTitle:      title,
		ProductCoverURL:   cover,
		ProductUnit:       unit,
		Items:             itemDTOs,
		QrcodeURLSnapshot: row.QrcodeURLSnapshot,
		CopyText:          row.CopyText,
		CancelReason:      row.CancelReason,
		PaidAt:            row.PaidAt,
		CompletedAt:       row.CompletedAt,
		CancelledAt:       row.CancelledAt,
		CreatedAt:         row.CreatedAt,
		UpdatedAt:         row.UpdatedAt,
	}
	if includeAdmin {
		// 后台展示真实手机号，便于履约联系买家
		dto.BuyerNickname = buyerNickname
		dto.BuyerPhone = strings.TrimSpace(buyerPhone)
		dto.AdminRemark = row.AdminRemark
	} else {
		dto.BuyerNickname = buyerNickname
		dto.BuyerPhone = maskPhone(buyerPhone)
	}
	return dto
}

func decodeStringList(raw []byte) []string {
	if len(raw) == 0 {
		return []string{}
	}
	var list []string
	if err := json.Unmarshal(raw, &list); err != nil {
		return []string{}
	}
	out := make([]string, 0, len(list))
	for _, item := range list {
		item = strings.TrimSpace(item)
		if item != "" {
			out = append(out, item)
		}
	}
	return out
}

func encodeStringList(list []string) []byte {
	clean := make([]string, 0, len(list))
	for _, item := range list {
		item = strings.TrimSpace(item)
		if item != "" {
			clean = append(clean, item)
		}
	}
	if len(clean) == 0 {
		return []byte("[]")
	}
	raw, err := json.Marshal(clean)
	if err != nil {
		return []byte("[]")
	}
	return raw
}

func decodeProductSnapshot(raw []byte) productSnapshot {
	var snap productSnapshot
	if len(raw) == 0 {
		return snap
	}
	_ = json.Unmarshal(raw, &snap)
	return snap
}

func maskPhone(phone string) string {
	phone = strings.TrimSpace(phone)
	if len(phone) < 7 {
		return phone
	}
	return phone[:3] + "****" + phone[len(phone)-4:]
}