package logic

import (
	"context"
	"errors"
	"sort"
	"strconv"
	"strings"
	"time"

	"bj_power_mes/ent"
	"bj_power_mes/ent/dailyplan"
	"bj_power_mes/ent/workorder"
	"bj_power_mes/ent/workpiece"
)

// parseDate 解析 yyyy-MM-dd 或标准时间
func parseDate(v string) (time.Time, error) {
	if t, err := time.ParseInLocation("2006-01-02", v, time.Local); err == nil {
		return t, nil
	}
	return time.ParseInLocation(time.RFC3339, v, time.Local)
}

type DailyPlanReq struct {
	Id           int      `json:"id"`
	OrderNo      string   `json:"orderNo"`
	PlanDate     string   `json:"planDate"`
	PlanQty      int      `json:"planQty"`
	CompletedQty int      `json:"completedQty"`
	Status       string   `json:"status"`
	DockCodes    []string `json:"dockCodes"`
}

// SaveDailyPlan 创建/更新日排产（同一 工单+日期 唯一）
// 排产状态枚举统一为：PENDING(待执行)/PROCESSING(执行中)/DONE(已完成)/CANCELLED(已取消)
func (s *Service) SaveDailyPlan(ctx context.Context, req DailyPlanReq, operator string) error {
	if req.OrderNo == "" || req.PlanDate == "" {
		return errors.New("工单号和排产日期必填")
	}
	// 校验：该工单所有日排产计划数量累计不得超过工单总数量(保存时合计，改小可、改大不超总量)
	wo, err := s.ctx.EntClient.WorkOrder.Query().Where(workorder.WorkOrderNo(req.OrderNo)).First(ctx)
	if err != nil {
		return errors.New("工单不存在")
	}
	if wo.Status == "DONE" || wo.Status == "CANCELLED" {
		return errors.New("该工单已完成或已取消，不能排产")
	}
	if wo.Status == "PAUSED" {
		return errors.New("该工单已暂停，恢复执行前不能新增排产")
	}
	cur, err := s.ctx.EntClient.DailyPlan.Query().
		Where(dailyplan.OrderNo(req.OrderNo)).All(ctx)
	if err != nil {
		return err
	}
	// 计算合计：本次 req.PlanQty 恒计入；若「工单+日期」已有记录，则原值作废只算新值（避免旧值+新值重复累计）
	total := req.PlanQty
	for _, p := range cur {
		if p.PlanDate == req.PlanDate {
			if p.CompletedQty > 0 {
				return errors.New("该排产日已有完工数量，不能修改计划数量")
			}
			continue
		}
		total += p.PlanQty
	}
	// 跨天在制品：只排「未开工数量 = 工单总数量 − 已完工 − 已进线未完工」，在产工件跨天继续、不被重排冲掉
	remain, err := s.unscheduledQty(ctx, wo)
	if err != nil {
		return err
	}
	if total > remain {
		return errors.New("排产合计数量超过未开工数量(工单总数量−已完工−在产未完工)，无法保存")
	}
	exist, err := s.ctx.EntClient.DailyPlan.Query().
		Where(dailyplan.OrderNo(req.OrderNo), dailyplan.PlanDate(req.PlanDate)).First(ctx)
	status := req.Status
	switch status {
	case "", "PENDING", "PROCESSING", "DONE", "CANCELLED", "CONFIRMED":
		if status == "" {
			status = "PENDING"
		}
	default:
		return errors.New("非法的排产状态")
	}
	if err == nil && exist != nil {
		_, err = s.ctx.EntClient.DailyPlan.UpdateOneID(exist.ID).
			SetOrderNo(req.OrderNo).SetPlanDate(req.PlanDate).SetPlanQty(req.PlanQty).SetStatus(status).
			SetDockCodes(dockCodes(req.DockCodes)).Save(ctx)
		if err != nil {
			return err
		}
	} else {
		_, err = s.ctx.EntClient.DailyPlan.Create().
			SetOrderNo(req.OrderNo).SetPlanDate(req.PlanDate).SetPlanQty(req.PlanQty).
			SetStatus(status).SetOperator(operator).SetDockCodes(dockCodes(req.DockCodes)).Save(ctx)
		if err != nil {
			return err
		}
	}
	// 记录该工单本次使用的接驳台到工单 context，供下次排产默认推荐
	if len(dockCodes(req.DockCodes)) > 0 {
		s.rememberOrderDocks(ctx, req.OrderNo, dockCodes(req.DockCodes))
	}
	s.ctx.EventLog.Write(ctx, "daily.plan.save", req.OrderNo, operator, "daily_plan", req.OrderNo, "保存日排产", map[string]any{"planDate": req.PlanDate, "planQty": req.PlanQty, "dockCodes": req.DockCodes})
	s.notifyDashboard()
	return nil
}

// dockCodes 规范化接驳台列表：仅保留 DOCK01..DOCK20 / DOCK21，去重、保持顺序
func dockCodes(codes []string) []string {
	seen := map[string]bool{}
	out := []string{}
	for _, c := range codes {
		c = strings.TrimSpace(c)
		if !validDockCode(c) || seen[c] {
			continue
		}
		seen[c] = true
		out = append(out, c)
	}
	return out
}

// validDockCode DOCK01..DOCK21
func validDockCode(c string) bool {
	if len(c) != 6 || !strings.HasPrefix(c, "DOCK") {
		return false
	}
	n, err := strconv.Atoi(c[4:])
	return err == nil && n >= 1 && n <= 21
}

// rememberOrderDocks 把工单「上次使用的接驳台」写入 work_order.context，供下次排产默认推荐
func (s *Service) rememberOrderDocks(ctx context.Context, orderNo string, docks []string) {
	if len(docks) == 0 {
		return
	}
	wo, err := s.ctx.EntClient.WorkOrder.Query().Where(workorder.WorkOrderNo(orderNo)).Only(ctx)
	if err != nil {
		return
	}
	c := wo.Context
	if c == nil {
		c = map[string]any{}
	}
	c["lastDockCodes"] = docks
	_ = s.ctx.EntClient.WorkOrder.UpdateOneID(wo.ID).SetContext(c).Exec(ctx)
}

// SuggestedDockCodes 查某工单「上次使用的接驳台」，供排产默认推荐
func (s *Service) SuggestedDockCodes(ctx context.Context, orderNo string) []string {
	wo, err := s.ctx.EntClient.WorkOrder.Query().Where(workorder.WorkOrderNo(orderNo)).Only(ctx)
	if err != nil {
		return nil
	}
	if v, ok := wo.Context["lastDockCodes"].([]any); ok {
		out := []string{}
		for _, x := range v {
			if s2, ok := x.(string); ok {
				out = append(out, s2)
			}
		}
		return out
	}
	return nil
}

// syncPlansByOrderStatus 工单状态联动日排产：
// - 工单 → IN_PROGRESS：该工单 PENDING 排产置 PROCESSING（开始执行）
// - 工单 → DONE：已足额完工(completedQty>=planQty)的排产置 DONE；其余未完成排产置 CANCELLED
// - 工单 → CANCELLED：该工单未完成(PENDING/PROCESSING)排产全部置 CANCELLED
func (s *Service) syncPlansByOrderStatus(ctx context.Context, orderNo, woStatus, operator string) {
	if orderNo == "" {
		return
	}
	plans, err := s.ctx.EntClient.DailyPlan.Query().
		Where(dailyplan.OrderNo(orderNo), dailyplan.StatusIn("PENDING", "PROCESSING")).All(ctx)
	if err != nil {
		return
	}
	changed := 0
	to := ""
	for _, p := range plans {
		switch woStatus {
		case "IN_PROGRESS":
			to = "PROCESSING"
		case "DONE":
			if p.CompletedQty >= p.PlanQty {
				to = "DONE"
			} else {
				to = "CANCELLED"
			}
		case "CANCELLED":
			to = "CANCELLED"
		default:
			return
		}
		if p.Status == to {
			continue
		}
		if _, err := s.ctx.EntClient.DailyPlan.UpdateOneID(p.ID).SetStatus(to).Save(ctx); err == nil {
			changed++
		}
	}
	if changed > 0 {
		s.ctx.EventLog.Write(ctx, "daily.plan.status_sync", orderNo, operator, "daily_plan", orderNo,
			"工单状态联动排产", map[string]any{"woStatus": woStatus, "changed": changed})
	}
}

// ListDailyPlans 按工单/日期查询日排产
func (s *Service) ListDailyPlans(ctx context.Context, orderNo, planDate string) ([]*ent.DailyPlan, error) {
	q := s.ctx.EntClient.DailyPlan.Query()
	if orderNo != "" {
		q = q.Where(dailyplan.OrderNo(orderNo))
	}
	if planDate != "" {
		q = q.Where(dailyplan.PlanDate(planDate))
	}
	return q.Order(ent.Desc(dailyplan.FieldPlanDate)).All(ctx)
}

// DeleteDailyPlan 删除一条日排产记录
func (s *Service) DeleteDailyPlan(ctx context.Context, id int) error {
	return s.ctx.EntClient.DailyPlan.DeleteOneID(id).Exec(ctx)
}

// ---------- 自动排产（引导式） ----------

// DateSegment 日期区间 [start, end]（含两端），yyyy-MM-dd
type DateSegment struct {
	Start string `json:"start"`
	End   string `json:"end"`
}

// AutoScheduleReq 引导式自动排产请求
// Mode: AVG(平均分摊到区间各天) / FIXED(固定日产 dailyQty)
// Segments: 一个或多个日期区间（如 6/23-26、6/28-29），区间并集去重排序
type AutoScheduleReq struct {
	OrderNo  string        `json:"orderNo"`
	Mode     string        `json:"mode"`
	DailyQty int           `json:"dailyQty"` // FIXED 模式每日产量
	Segments []DateSegment `json:"segments"`
}

// unscheduledQty 未开工数量 = 工单总数量 − 已完工 − 已进线未完工（跨天在制品不重排）
func (s *Service) unscheduledQty(ctx context.Context, wo *ent.WorkOrder) (int, error) {
	inLine, err := s.ctx.EntClient.Workpiece.Query().
		Where(workpiece.OrderNo(wo.WorkOrderNo), workpiece.StatusIn("ONLINE", "PROCESSING")).Count(ctx)
	if err != nil {
		return 0, err
	}
	remain := wo.Quantity - wo.FinishedNum - inLine
	if remain < 0 {
		remain = 0
	}
	return remain, nil
}

// expandDates 把多个日期区间展开为去重、升序的日期列表（yyyy-MM-dd）
func expandDates(segments []DateSegment) ([]string, error) {
	seen := map[string]bool{}
	out := []string{}
	for _, seg := range segments {
		start, e1 := time.ParseInLocation("2006-01-02", seg.Start, time.Local)
		end, e2 := time.ParseInLocation("2006-01-02", seg.End, time.Local)
		if e1 != nil || e2 != nil || !end.After(start) && !end.Equal(start) {
			return nil, errors.New("日期区间格式错误（应为 yyyy-MM-dd，且结束≥开始）：" + seg.Start + "~" + seg.End)
		}
		for d := start; !d.After(end); d = d.AddDate(0, 0, 1) {
			ds := d.Format("2006-01-02")
			if !seen[ds] {
				seen[ds] = true
				out = append(out, ds)
			}
		}
	}
	sort.Strings(out)
	return out, nil
}

// AutoSchedule 引导式自动排产：生成多条 daily_plan（status=PENDING，未启用），供人工确认后启用。
// 排产合计（含已有排产）≤ 未开工数量；已进线未完工工件跨天继续、不被重排冲掉。
func (s *Service) AutoSchedule(ctx context.Context, req AutoScheduleReq, operator string) error {
	if req.OrderNo == "" {
		return errors.New("工单号必填")
	}
	if req.Mode != "AVG" && req.Mode != "FIXED" {
		return errors.New("排产模式仅支持 AVG(平均分摊) / FIXED(固定日产)")
	}
	dates, err := expandDates(req.Segments)
	if err != nil {
		return err
	}
	if len(dates) == 0 {
		return errors.New("请至少选择一个日期区间")
	}
	wo, err := s.ctx.EntClient.WorkOrder.Query().Where(workorder.WorkOrderNo(req.OrderNo)).First(ctx)
	if err != nil {
		return errors.New("工单不存在")
	}
	if wo.Status == "DONE" || wo.Status == "CANCELLED" {
		return errors.New("该工单已完成或已取消，不能排产")
	}
	if wo.Status == "PAUSED" {
		return errors.New("该工单已暂停，恢复执行前不能排产")
	}
	remain, err := s.unscheduledQty(ctx, wo)
	if err != nil {
		return err
	}
	// 已有排产（非本次区间内的）已占用部分未开工数量，本次可排上限 = remain − 既有排产合计
	exist, _ := s.ctx.EntClient.DailyPlan.Query().Where(dailyplan.OrderNo(req.OrderNo)).All(ctx)
	existTotal := 0
	for _, p := range exist {
		existTotal += p.PlanQty
	}
	quota := remain - existTotal
	if quota < 0 {
		quota = 0
	}

	days := len(dates)
	var planQty []int
	switch req.Mode {
	case "AVG":
		base := quota / days
		planQty = make([]int, days)
		for i := range planQty {
			planQty[i] = base
		}
		// 余数补到前面几天，保证合计=quota
		for i := 0; i < quota-base*days; i++ {
			planQty[i]++
		}
	case "FIXED":
		if req.DailyQty <= 0 {
			return errors.New("固定日产模式需填写每日产量(>0)")
		}
		planQty = make([]int, days)
		left := quota
		for i := range planQty {
			if left >= req.DailyQty {
				planQty[i] = req.DailyQty
				left -= req.DailyQty
			} else {
				planQty[i] = left
				left = 0
			}
		}
		if quota > req.DailyQty*days {
			return errors.New("固定日产×天数超过未开工数量，无法排产")
		}
	}
	sum := 0
	for _, q := range planQty {
		sum += q
	}
	if sum == 0 {
		return errors.New("未开工数量为 0，无需排产（已在产/已完工）")
	}

	// 生成/更新排产（本次区间内的日期覆盖式写入，status=PENDING 待人工启用；执行中/已完工的日计划受保护不被覆盖）
	for i, ds := range dates {
		q := planQty[i]
		if q <= 0 {
			continue
		}
		existOne, _ := s.ctx.EntClient.DailyPlan.Query().
			Where(dailyplan.OrderNo(req.OrderNo), dailyplan.PlanDate(ds)).First(ctx)
		if existOne != nil {
			// 保护执行中/已完成的排产（方案 K / P2-3）：不打回 PENDING、不覆盖数量，
			// 避免自动排产把正在产线执行(PROCESSING)或已完工(DONE)的日计划冲掉；
			// 这些计划的既有数量已在 existTotal 中计入、quota 已相应扣减，跳过不会超排。
			if existOne.Status == "PROCESSING" || existOne.Status == "DONE" {
				continue
			}
			_, err = s.ctx.EntClient.DailyPlan.UpdateOneID(existOne.ID).
				SetPlanQty(q).SetStatus("PENDING").SetOperator(operator).Save(ctx)
		} else {
			_, err = s.ctx.EntClient.DailyPlan.Create().
				SetOrderNo(req.OrderNo).SetPlanDate(ds).SetPlanQty(q).
				SetStatus("PENDING").SetOperator(operator).Save(ctx)
		}
		if err != nil {
			return err
		}
	}
	s.ctx.EventLog.Write(ctx, "daily.plan.auto", req.OrderNo, operator, "daily_plan", req.OrderNo,
		"自动排产(模式="+req.Mode+")", map[string]any{"days": days, "total": sum, "quota": quota})
	s.notifyDashboard()
	return nil
}