package handler

import (
	"net/http"
	"strconv"
	"time"

	"bj_power_wms/ent"
	"bj_power_wms/ent/zone"
	"bj_power_wms/internal/svc"
)

// createZoneHandler 创建区域
func createZoneHandler(ctx *svc.ServiceContext) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		var req struct {
			ZoneCode    string `json:"zoneCode"`
			ZoneName    string `json:"zoneName"`
			Description string `json:"description"`
			ShelfNo     string `json:"shelfNo"`
			LayerNo     string `json:"layerNo"`
			PositionNo  string `json:"positionNo"`
		}
		if err := parseJSON(r, &req); err != nil {
			fail(w, http.StatusBadRequest, "参数错误")
			return
		}
		if req.ZoneCode == "" || req.ZoneName == "" {
			fail(w, http.StatusBadRequest, "区域编码和区域名称必填")
			return
		}

		// 货位唯一性（U18）：按四级组合(区域+货架+层+位置)判重，与 DB 组合唯一索引 ux_zones_location 一致。
		// zone_code 不再单列唯一——同一区域下可登记多个货位（NULL/空串归一为""比较，与 COALESCE 索引一致）。
		sameZone, err := ctx.EntClient.Zone.Query().
			Where(zone.ZoneCodeEQ(req.ZoneCode)).
			All(ctx0())
		if err != nil {
			fail(w, http.StatusInternalServerError, err.Error())
			return
		}
		for _, sz := range sameZone {
			if sz.ShelfNo == req.ShelfNo && sz.LayerNo == req.LayerNo && sz.PositionNo == req.PositionNo {
				fail(w, http.StatusConflict, locDupMsg(req.ZoneCode, req.ShelfNo, req.LayerNo, req.PositionNo))
				return
			}
		}

		z, err := ctx.EntClient.Zone.Create().
			SetZoneCode(req.ZoneCode).
			SetZoneName(req.ZoneName).
			SetNillableDescription(strPtr(req.Description)).
			SetNillableShelfNo(strPtr(req.ShelfNo)).
			SetNillableLayerNo(strPtr(req.LayerNo)).
			SetNillablePositionNo(strPtr(req.PositionNo)).
			SetStatus("启用").
			Save(ctx0())
		if err != nil {
			fail(w, http.StatusInternalServerError, err.Error())
			return
		}
		ctx.EventLog.Write(ctx0(), "zone.create", r.Header.Get("X-Username"), "zone", z.ZoneCode,
			"新建区域 "+req.ZoneName, nil)
		ok(w, z)
	}
}

// updateZoneHandler 编辑区域
func updateZoneHandler(ctx *svc.ServiceContext) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		var req struct {
			ID          int    `json:"id"`
			ZoneCode    string `json:"zoneCode"`
			ZoneName    string `json:"zoneName"`
			Description string `json:"description"`
			ShelfNo     string `json:"shelfNo"`
			LayerNo     string `json:"layerNo"`
			PositionNo  string `json:"positionNo"`
		}
		if err := parseJSON(r, &req); err != nil || req.ID <= 0 {
			fail(w, http.StatusBadRequest, "参数错误")
			return
		}
		if req.ZoneName == "" {
			fail(w, http.StatusBadRequest, "区域名称必填")
			return
		}
		// 货位唯一性（排除自身，U18）：改后四级组合不得与其他货位重复（DB 组合唯一索引兜底）。
		if req.ZoneCode != "" {
			others, e := ctx.EntClient.Zone.Query().
				Where(zone.ZoneCodeEQ(req.ZoneCode), zone.IDNEQ(req.ID)).All(ctx0())
			if e != nil {
				fail(w, http.StatusInternalServerError, e.Error())
				return
			}
			for _, oz := range others {
				if oz.ShelfNo == req.ShelfNo && oz.LayerNo == req.LayerNo && oz.PositionNo == req.PositionNo {
					fail(w, http.StatusConflict, locDupMsg(req.ZoneCode, req.ShelfNo, req.LayerNo, req.PositionNo))
					return
				}
			}
		}
		upd := ctx.EntClient.Zone.UpdateOneID(req.ID).SetZoneName(req.ZoneName)
		if req.ZoneCode != "" {
			upd.SetZoneCode(req.ZoneCode)
		}
		upd.SetNillableDescription(strPtr(req.Description))
		upd.SetNillableShelfNo(strPtr(req.ShelfNo))
		upd.SetNillableLayerNo(strPtr(req.LayerNo))
		upd.SetNillablePositionNo(strPtr(req.PositionNo))
		z, err := upd.Save(ctx0())
		if err != nil {
			fail(w, http.StatusInternalServerError, "更新区域失败: "+err.Error())
			return
		}
		ctx.EventLog.Write(ctx0(), "zone.update", r.Header.Get("X-Username"), "zone", req.ZoneCode,
			"编辑区域 #"+strconv.Itoa(req.ID)+" "+req.ZoneName, nil)
		ok(w, z)
	}
}

// listZonesHandler 区域列表（分页 + 关键字）
func listZonesHandler(ctx *svc.ServiceContext) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		page := atoi(r.URL.Query().Get("page"), 1)
		pageSize := atoi(r.URL.Query().Get("pageSize"), 20)
		zoneCode := r.URL.Query().Get("zoneCode")
		zoneName := r.URL.Query().Get("zoneName")
		status := r.URL.Query().Get("status")
		startDate := r.URL.Query().Get("startDate")
		endDate := r.URL.Query().Get("endDate")

		q := ctx.EntClient.Zone.Query()
		if zoneCode != "" {
			// 区域编码搜索大小写不敏感
			q = q.Where(zone.ZoneCodeContainsFold(zoneCode))
		}
		if zoneName != "" {
			q = q.Where(zone.ZoneNameContainsFold(zoneName))
		}
		if status != "" {
			q = q.Where(zone.StatusEQ(status))
		}
		if startDate != "" {
			if t, err := time.ParseInLocation("2006-01-02", startDate, time.Local); err == nil {
				q = q.Where(zone.CreatedAtGTE(t.Unix()))
			}
		}
		if endDate != "" {
			if t, err := time.ParseInLocation("2006-01-02", endDate, time.Local); err == nil {
				q = q.Where(zone.CreatedAtLTE(t.Add(24 * time.Hour).Unix()))
			}
		}
		total, err := q.Count(ctx0())
		if err != nil {
			fail(w, http.StatusInternalServerError, err.Error())
			return
		}
		list, err := q.Order(ent.Asc("id")).
			Offset((page - 1) * pageSize).
			Limit(pageSize).
			All(ctx0())
		if err != nil {
			fail(w, http.StatusInternalServerError, err.Error())
			return
		}
		ok(w, map[string]any{
			"total":    total,
			"list":     list,
			"page":     page,
			"pageSize": pageSize,
		})
	}
}

// listZonesForPicker 区域下拉列表（不分页，仅启用）
func listZonesForPicker(ctx *svc.ServiceContext) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		list, err := ctx.EntClient.Zone.Query().
			Where(zone.StatusEQ("启用")).
			Order(ent.Asc("id")).
			All(ctx0())
		if err != nil {
			fail(w, http.StatusInternalServerError, err.Error())
			return
		}
		ok(w, list)
	}
}

// locDupMsg 货位重复登记的统一提示（复用 locLabel 拼四级货位串，U18）。
func locDupMsg(zoneCode, shelfNo, layerNo, positionNo string) string {
	return "该货位已存在：" + locLabel(zoneCode, shelfNo, layerNo, positionNo)
}