package handler

import (
	"fmt"
	"net/http"
	"strings"
	"time"

	"entgo.io/ent/dialect/sql"
	"bj_power_wms/ent"
	"bj_power_wms/ent/inventory"
	"bj_power_wms/ent/inventorylock"
	"bj_power_wms/ent/material"
	"bj_power_wms/ent/predicate"
	"bj_power_wms/internal/svc"
)

// stockKey 库存聚合行的唯一标识（组合键）+ 明细下钻的过滤条件
type stockKey struct {
	MaterialCode  string
	ZoneCode      string
	QualityStatus string
	ManageMode    int
}

// stockAggRow 聚合主列表的行结构（按 物料+区域+质量+管理粒度 聚合，只返回数量，不铺开明细）
type stockAggRow struct {
	ID            int64  `json:"id"`            // 组合键稳定序号的伪 id，供前端行 key 使用
	MaterialCode  string `json:"materialCode"`  // 物料编码
	MaterialName  string `json:"materialName"`  // 物料名称
	Spec          string `json:"spec"`          // 规格型号
	ManageMode    int    `json:"manageMode"`    // 1结构件/2精密件
	ZoneCode      string `json:"zoneCode"`      // 区域
	QualityStatus string `json:"qualityStatus"` // 质量状态
	TotalQty      int    `json:"totalQty"`      // 总数量（结构件=数量求和；精密件=SN 行数）
	LockedQty     int    `json:"lockedQty"`     // 锁定量
	AvailQty      int    `json:"availQty"`      // 可用量 = total - locked
	BatchCount    int    `json:"batchCount"`    // 批次数量（结构件维度的行数）
	SnCount       int    `json:"snCount"`       // SN 数量（精密件维度的行数）
	LastInboundNo string `json:"lastInboundNo"` // 最近入库单号
	CreatedAt     int64  `json:"createdAt"`     // 最近一次入库时间（聚合组内最大 created_at）
}

// queryStockHandler 库存查询（主列表 = 按物料聚合数量）
// 统一查询 inventory 一张表，按 物料编码+区域+质量状态+管理粒度 分组聚合，
// 只返回每个物料的数量/锁定/可用与 批次数/SN数，不把每个批次/SN 平铺出来（避免 SN 泄漏与数据量膨胀）。
// 明细通过 /api/stock/details 点击下钻（分页懒加载）。
func queryStockHandler(ctx *svc.ServiceContext) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		materialCode := r.URL.Query().Get("materialCode")
		materialName := r.URL.Query().Get("materialName") // 物料名称模糊
		zoneCode := r.URL.Query().Get("zoneCode")
		qualityStatus := r.URL.Query().Get("qualityStatus")
		manageMode := r.URL.Query().Get("manageMode") // 1/2/空=全部
		inboundNo := r.URL.Query().Get("inboundNo")
		startDate := r.URL.Query().Get("startDate") // 默认近3个月（由接口保证）
		endDate := r.URL.Query().Get("endDate")
		page := atoi(r.URL.Query().Get("page"), 1)
		pageSize := atoi(r.URL.Query().Get("pageSize"), 20)

		rows, total, err := aggregateStock(ctx, aggregateStockArgs{
			MaterialCode:  materialCode,
			MaterialName:  materialName,
			ZoneCode:      zoneCode,
			QualityStatus: qualityStatus,
			ManageMode:    manageMode,
			InboundNo:     inboundNo,
			StartDate:     startDate,
			EndDate:       endDate,
			Page:          page,
			PageSize:      pageSize,
		})
		if err != nil {
			fail(w, http.StatusInternalServerError, err.Error())
			return
		}
		ok(w, map[string]any{
			"list":     rows,
			"total":    total,
			"page":     page,
			"pageSize": pageSize,
		})
	}
}

// aggregateStockArgs 聚合主列表的筛选条件
type aggregateStockArgs struct {
	MaterialCode  string
	MaterialName  string
	ZoneCode      string
	QualityStatus string
	ManageMode    string
	InboundNo     string
	StartDate     string
	EndDate       string
	Page          int
	PageSize      int
}

// aggregateStock 按物料聚合库存主数据。
// 用相机内存聚合（inventory 表每物料的行数有限：结构件=批次数、精密件=SN 数），
// 先拉取符合状态条件的行，在 Go 侧分组聚合，再做内存分页。
// 这样避免手写 GROUP BY 子查询的复杂度，且数据量受"在库/锁定"上限约束，安全可控。
func aggregateStock(ctx *svc.ServiceContext, a aggregateStockArgs) ([]*stockAggRow, int, error) {
	q := ctx.EntClient.Inventory.Query()
	// 仅展示在库/锁定（出库/使用/报废不计入库存）
	q = q.Where(inventory.StatusIn("在库", "锁定"))
	// 结构件隐藏数量为 0 的行
	q = q.Where(inventory.Or(inventory.ManageModeEQ(2), inventory.QuantityGT(0)))

	if a.MaterialCode != "" {
		q = q.Where(inventory.MaterialCodeContains(a.MaterialCode))
	}
	if a.MaterialName != "" {
		q = q.Where(inventory.MaterialNameContains(a.MaterialName))
	}
	if a.ZoneCode != "" {
		q = q.Where(inventory.ZoneCodeEQ(a.ZoneCode))
	}
	if a.QualityStatus != "" {
		q = q.Where(inventory.QualityStatusEQ(a.QualityStatus))
	}
	if a.InboundNo != "" {
		q = q.Where(inventory.InboundNoContains(a.InboundNo))
	}
	if a.ManageMode == "1" {
		q = q.Where(inventory.ManageModeEQ(1))
	} else if a.ManageMode == "2" {
		q = q.Where(inventory.ManageModeEQ(2))
	}
	// 时间筛选：默认近3个月
	startUnix := int64(0)
	if a.StartDate != "" {
		if t, err := time.ParseInLocation("2006-01-02", a.StartDate, time.Local); err == nil {
			startUnix = t.Unix()
		}
	}
	endUnix := int64(0)
	if a.EndDate != "" {
		if t, err := time.ParseInLocation("2006-01-02", a.EndDate, time.Local); err == nil {
			endUnix = t.Add(24 * time.Hour).Unix() // 含当天全天
		}
	}
	if a.StartDate == "" && a.EndDate == "" {
		startUnix = time.Now().AddDate(0, -3, 0).Unix() // 默认近3个月
	}
	if startUnix > 0 {
		q = q.Where(inventory.CreatedAtGTE(startUnix))
	}
	if endUnix > 0 {
		q = q.Where(inventory.CreatedAtLTE(endUnix))
	}

	all, err := q.Order(ent.Desc("created_at")).All(ctx0())
	if err != nil {
		return nil, 0, err
	}

	// 收集物料信息（名称/规格从 materials 表补齐，字段更权威）
	matName := map[string]string{}
	matSpec := map[string]string{}
	matCodes := []string{}
	seen := map[string]bool{}
	for _, inv := range all {
		if !seen[inv.MaterialCode] {
			seen[inv.MaterialCode] = true
			matCodes = append(matCodes, inv.MaterialCode)
		}
	}
	if len(matCodes) > 0 {
		mats, _ := ctx.EntClient.Material.Query().
			Where(material.CodeIn(matCodes...)).All(ctx0())
		for _, m := range mats {
			matName[m.Code] = m.Name
			matSpec[m.Code] = m.Spec
		}
	}

	// 分组聚合
	type agg struct {
		totalQty  int
		lockedQty int
		batchCnt  int
		snCnt     int
		lastInbNo string
		lastTime  int64
	}
	group := map[stockKey]*agg{}
	order := []stockKey{}
	for _, inv := range all {
		zc := inv.ZoneCode
		if zc == "" {
			zc = "未分区"
		}
		key := stockKey{inv.MaterialCode, zc, inv.QualityStatus, inv.ManageMode}
		g, ok := group[key]
		if !ok {
			g = &agg{}
			group[key] = g
			order = append(order, key)
		}
		if inv.ManageMode == 1 {
			g.totalQty += inv.Quantity
			g.lockedQty += inv.LockedQty
			g.batchCnt++
		} else {
			g.totalQty++
			if inv.Status == "锁定" {
				g.lockedQty++
			}
			g.snCnt++
		}
		if inv.CreatedAt > g.lastTime {
			g.lastTime = inv.CreatedAt
			g.lastInbNo = inv.InboundNo
		}
	}

	total := len(order)
	// 分页
	start := (a.Page - 1) * a.PageSize
	if start < 0 {
		start = 0
	}
	end := start + a.PageSize
	if end > total {
		end = total
	}
	rows := make([]*stockAggRow, 0, end-start)
	for i := start; i < end; i++ {
		key := order[i]
		g := group[key]
		name := matName[key.MaterialCode]
		if name == "" {
			name = key.MaterialCode
		}
		rows = append(rows, &stockAggRow{
			ID:            int64(i + 1),
			MaterialCode:  key.MaterialCode,
			MaterialName:  name,
			Spec:          matSpec[key.MaterialCode],
			ManageMode:    key.ManageMode,
			ZoneCode:      key.ZoneCode,
			QualityStatus: key.QualityStatus,
			TotalQty:      g.totalQty,
			LockedQty:     g.lockedQty,
			AvailQty:      g.totalQty - g.lockedQty,
			BatchCount:    g.batchCnt,
			SnCount:       g.snCnt,
			LastInboundNo: g.lastInbNo,
			CreatedAt:     g.lastTime,
		})
	}
	return rows, total, nil
}

// stockDetailsHandler 库存明细（点击聚合行下钻，分页懒加载）
// GET /api/stock/details?materialCode=&zoneCode=&qualityStatus=&manageMode=&page=&pageSize=
// 返回该物料/区域/质量/类型下的原始批次/SN 明细行（扁平展示，含 SN/批次号）。
func stockDetailsHandler(ctx *svc.ServiceContext) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		materialCode := r.URL.Query().Get("materialCode")
		zoneCode := r.URL.Query().Get("zoneCode")
		if zoneCode == "未分区" {
			zoneCode = ""
		}
		qualityStatus := r.URL.Query().Get("qualityStatus")
		manageMode := atoi(r.URL.Query().Get("manageMode"), 0)
		page := atoi(r.URL.Query().Get("page"), 1)
		pageSize := atoi(r.URL.Query().Get("pageSize"), 50)

		q := ctx.EntClient.Inventory.Query()
		q = q.Where(inventory.StatusIn("在库", "锁定"))
		q = q.Where(inventory.Or(inventory.ManageModeEQ(2), inventory.QuantityGT(0)))
		if materialCode != "" {
			q = q.Where(inventory.MaterialCodeEQ(materialCode))
		}
		if zoneCode != "" {
			q = q.Where(inventory.ZoneCodeEQ(zoneCode))
		}
		if qualityStatus != "" {
			q = q.Where(inventory.QualityStatusEQ(qualityStatus))
		}
		if manageMode != 0 {
			q = q.Where(inventory.ManageModeEQ(manageMode))
		}

		total, err := q.Count(ctx0())
		if err != nil {
			fail(w, http.StatusInternalServerError, err.Error())
			return
		}
		list, err := q.Order(ent.Desc("created_at")).
			Offset((page - 1) * pageSize).Limit(pageSize).All(ctx0())
		if err != nil {
			fail(w, http.StatusInternalServerError, err.Error())
			return
		}
		ok(w, map[string]any{
			"list":     list,
			"total":    total,
			"page":     page,
			"pageSize": pageSize,
		})
	}
}

// exportStockHandler 库存汇总全量导出（xlsx）
// 与 /stock/query 同一套聚合逻辑，但导出当前筛选下的全部行（不分页）。
// 返回 .xlsx 二进制，文件名 = 库存汇总_时间.xlsx。
func exportStockHandler(ctx *svc.ServiceContext) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		rows, _, err := aggregateStock(ctx, aggregateStockArgs{
			MaterialCode:  r.URL.Query().Get("materialCode"),
			MaterialName:  r.URL.Query().Get("materialName"),
			ZoneCode:      r.URL.Query().Get("zoneCode"),
			QualityStatus: r.URL.Query().Get("qualityStatus"),
			ManageMode:    r.URL.Query().Get("manageMode"),
			InboundNo:     r.URL.Query().Get("inboundNo"),
			StartDate:     r.URL.Query().Get("startDate"),
			EndDate:       r.URL.Query().Get("endDate"),
			Page:          1,
			PageSize:      1000000, // 全量
		})
		if err != nil {
			fail(w, http.StatusInternalServerError, err.Error())
			return
		}
		headers := []string{"物料编码", "物料名称", "规格", "类型", "区域", "质量状态", "总数量", "锁定量", "可用量", "批次数", "SN数", "最近入库单", "最近入库时间"}
		matrix := make([][]any, 0, len(rows))
		for _, rw := range rows {
			matrix = append(matrix, []any{
				rw.MaterialCode, rw.MaterialName, rw.Spec,
				manageModeLabel(rw.ManageMode), rw.ZoneCode, rw.QualityStatus,
				rw.TotalQty, rw.LockedQty, rw.AvailQty, rw.BatchCount, rw.SnCount,
				rw.LastInboundNo, unixFmt(rw.CreatedAt),
			})
		}
		sendExcel(w, xlsxFilename("库存汇总"), headers, matrix)
	}
}
// zoneSummaryHandler 区域库存汇总（按 区域 + 质量状态 + 类型 聚合）
// GET /api/stock/zone-summary
// 返回 rows: [{zoneCode, zoneName, quality, type(批次/精密件), qty}]
// 仅按"区域(Z01~Z04)"维度聚合，不引入货架/层/格（业务决策：小货架高频取货无需精确货位索引）。
func zoneSummaryHandler(ctx *svc.ServiceContext) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		zones, _ := ctx.EntClient.Zone.Query().All(ctx0())
		zoneNameMap := map[string]string{}
		for _, z := range zones {
			zoneNameMap[z.ZoneCode] = z.ZoneName
		}

		rows, _ := ctx.EntClient.Inventory.Query().
			Where(inventory.StatusIn("在库", "锁定")).All(ctx0())

		type summRow struct {
			ZoneCode string `json:"zoneCode"`
			ZoneName string `json:"zoneName"`
			Quality  string `json:"quality"`
			Type     string `json:"type"` // 批次/精密件
			Qty      int    `json:"qty"`
		}
		agg := map[string]int{} // key: zc|quality|type
		for _, inv := range rows {
			zc := inv.ZoneCode
			if zc == "" {
				zc = "未分区"
			}
			t := "批次"
			if inv.ManageMode == 2 {
				t = "精密件"
			}
			key := zc + "|" + inv.QualityStatus + "|" + t
			if inv.ManageMode == 1 {
				agg[key] += inv.Quantity
			} else {
				agg[key] += 1
			}
		}

		out := make([]summRow, 0, len(agg))
		for k, v := range agg {
			parts := strings.Split(k, "|")
			name := zoneNameMap[parts[0]]
			if name == "" {
				name = parts[0]
			}
			out = append(out, summRow{parts[0], name, parts[1], parts[2], v})
		}
		ok(w, map[string]any{"rows": out})
	}
}

// invAvailGTE 自定义谓词：可用量(quantity - locked_qty) >= need
// 用于锁库存时的原子条件校验，避免并发超锁。
func invAvailGTE(need int) predicate.Inventory {
	return predicate.Inventory(func(s *sql.Selector) {
		s.Where(sql.ExprP(
			fmt.Sprintf("%s.%s - %s.%s >= ?",
				inventory.Table, inventory.FieldQuantity,
				inventory.Table, inventory.FieldLockedQty),
			need,
		))
	})
}

// lockStockHandler 工单锁定库存（库存占用）
// body: { orderNo, items: [{ materialCode, batchNo?, sn?, qty }] }
// 锁定为"增量"操作：结构件 locked_qty += qty；精密件状态置 锁定。绝不覆盖终值。
// 锁批次用原子增量 + 可用量条件校验；锁 SN 用状态条件原子更新，杜绝超锁与并发冲突。
func lockStockHandler(ctx *svc.ServiceContext) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		var req struct {
			OrderNo string `json:"orderNo"`
			Items   []struct {
				MaterialCode string `json:"materialCode"`
				BatchNo      string `json:"batchNo"`
				Sn           string `json:"sn"`
				Qty          int    `json:"qty"`
			} `json:"items"`
		}
		if err := parseJSON(r, &req); err != nil {
			fail(w, http.StatusBadRequest, "参数错误: "+err.Error())
			return
		}
		if req.OrderNo == "" || len(req.Items) == 0 {
			fail(w, http.StatusBadRequest, "orderNo 和 items 必填")
			return
		}

		locked := 0
		for _, item := range req.Items {
			if item.MaterialCode == "" {
				continue
			}
			// 精密件：锁 SN（原子：仅 在库 才能锁）
			if item.Sn != "" {
				aff, err := ctx.EntClient.Inventory.Update().
					Where(inventory.ManageModeEQ(2), inventory.SnCodeEQ(item.Sn), inventory.StatusEQ("在库")).
					SetStatus("锁定").SetLockedQty(1).
					Save(ctx0())
				if err != nil {
					fail(w, http.StatusInternalServerError, "锁定 SN 失败: "+err.Error())
					return
				}
				if aff == 0 {
					fail(w, http.StatusBadRequest, "SN 不在库或不存在: "+item.Sn)
					return
				}
				ctx.EntClient.InventoryLock.Create().
					SetTargetType("SN").
					SetTargetID(item.Sn).
					SetMaterialCode(item.MaterialCode).
					SetLockedQty(1).
					SetOrderNo(req.OrderNo).
					SetStatus("ACTIVE").
					SaveX(ctx0())
				locked++
				continue
			}

			// 结构件：锁批次数量（原子增量 + 可用量校验）
			qty := item.Qty
			if qty <= 0 {
				qty = 1
			}
			b, err := ctx.EntClient.Inventory.Query().
				Where(inventory.ManageModeEQ(1), inventory.BatchNoEQ(item.BatchNo)).Only(ctx0())
			if err != nil {
				fail(w, http.StatusBadRequest, "批次不存在: "+item.BatchNo)
				return
			}
			avail := b.Quantity - b.LockedQty
			if avail < qty {
				fail(w, http.StatusConflict, "批次库存不足: "+item.BatchNo+" 可用 "+itoa(avail))
				return
			}
			aff, err := ctx.EntClient.Inventory.Update().
				Where(inventory.ID(b.ID), invAvailGTE(qty)).
				AddLockedQty(qty).
				Save(ctx0())
			if err != nil || aff == 0 {
				fail(w, http.StatusConflict, "锁定失败(库存不足或并发冲突): "+item.BatchNo)
				return
			}
			ctx.EntClient.InventoryLock.Create().
				SetTargetType("BATCH").
				SetTargetID(item.BatchNo).
				SetMaterialCode(item.MaterialCode).
				SetLockedQty(qty).
				SetOrderNo(req.OrderNo).
				SetStatus("ACTIVE").
				SaveX(ctx0())
			locked += qty
		}

		ok(w, map[string]any{"locked": locked})
	}
}

// unlockStockHandler 释放库存锁定（取消锁定/返工）
func unlockStockHandler(ctx *svc.ServiceContext) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		var req struct {
			OrderNo string `json:"orderNo"`
			LockIDs []int  `json:"lockIds"`
		}
		if err := parseJSON(r, &req); err != nil {
			fail(w, http.StatusBadRequest, "参数错误")
			return
		}

		q := ctx.EntClient.InventoryLock.Query().
			Where(inventorylock.StatusEQ("ACTIVE"))
		if req.OrderNo != "" {
			q = q.Where(inventorylock.OrderNoEQ(req.OrderNo))
		}
		if len(req.LockIDs) > 0 {
			q = q.Where(inventorylock.IDIn(req.LockIDs...))
		}
		locks, err := q.All(ctx0())
		if err != nil {
			fail(w, http.StatusInternalServerError, err.Error())
			return
		}

		released := 0
		for _, l := range locks {
			// 还原批次锁定数 / SN 状态
			if l.TargetType == "BATCH" {
				ctx.EntClient.Inventory.Update().
					Where(inventory.BatchNoEQ(l.TargetID)).
					AddLockedQty(-l.LockedQty).
					SaveX(ctx0())
				// 防止并发下锁定数为负
				ctx.EntClient.Inventory.Update().
					Where(inventory.BatchNoEQ(l.TargetID), inventory.LockedQtyLT(0)).
					SetLockedQty(0).
					SaveX(ctx0())
			} else if l.TargetType == "SN" {
				ctx.EntClient.Inventory.Update().
					Where(inventory.SnCodeEQ(l.TargetID), inventory.StatusEQ("锁定")).
					SetStatus("在库").SetLockedQty(0).
					SaveX(ctx0())
			}
			ctx.EntClient.InventoryLock.UpdateOneID(l.ID).
				SetStatus("RELEASED").ExecX(ctx0())
			released++
		}

		ok(w, map[string]any{"released": released})
	}
}

// checkStockHandler 校验库存是否满足需求（锁库前检查）
func checkStockHandler(ctx *svc.ServiceContext) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		var req struct {
			Items []struct {
				MaterialCode string `json:"materialCode"`
				Qty          int    `json:"qty"`
			} `json:"items"`
		}
		if err := parseJSON(r, &req); err != nil {
			fail(w, http.StatusBadRequest, "参数错误")
			return
		}

		results := make([]map[string]any, 0, len(req.Items))
		allOk := true
		for _, item := range req.Items {
			// 汇总可用量：结构件 quantity-locked_qty；精密件 在库数量
			rows, _ := ctx.EntClient.Inventory.Query().
				Where(inventory.MaterialCodeEQ(item.MaterialCode)).All(ctx0())
			availBatch := 0
			availSerial := 0
			for _, row := range rows {
				if row.ManageMode == 1 {
					availBatch += row.Quantity - row.LockedQty
				} else if row.Status == "在库" {
					availSerial++
				}
			}
			enough := availBatch+availSerial >= item.Qty
			if !enough {
				allOk = false
			}
			results = append(results, map[string]any{
				"materialCode": item.MaterialCode,
				"requireQty":   item.Qty,
				"availQty":     availBatch + availSerial,
				"batchAvail":   availBatch,
				"serialAvail":  availSerial,
				"enough":       enough,
			})
		}

		ok(w, map[string]any{"allOk": allOk, "items": results})
	}
}

func itoa(n int) string {
	if n == 0 {
		return "0"
	}
	neg := n < 0
	if neg {
		n = -n
	}
	var b [20]byte
	i := len(b)
	for n > 0 {
		i--
		b[i] = byte('0' + n%10)
		n /= 10
	}
	if neg {
		i--
		b[i] = '-'
	}
	return string(b[i:])
}