package logic

import (
	"context"
	"database/sql"
	"strconv"
	"strings"

	"muyu-apiserver/model"
	"muyu-apiserver/pkg/metrics"
	"muyu-apiserver/pkg/tenantctx"
	"muyu-apiserver/pkg/uid"
	"muyu-apiserver/rpc/inventory/internal/svc"
	"muyu-apiserver/rpc/inventory/pb"

	"github.com/zeromicro/go-zero/core/logx"
	"google.golang.org/grpc/codes"
	"google.golang.org/grpc/status"
)

type CreateProductLogic struct {
	ctx    context.Context
	svcCtx *svc.ServiceContext
	logx.Logger
}

func NewCreateProductLogic(ctx context.Context, svcCtx *svc.ServiceContext) *CreateProductLogic {
	return &CreateProductLogic{
		ctx:    ctx,
		svcCtx: svcCtx,
		Logger: logx.WithContext(ctx),
	}
}

func (l *CreateProductLogic) CreateProduct(in *pb.CreateProductReq) (*pb.IdResp, error) {
	tenantId := tenantctx.ExtractTenantId(l.ctx)
	productId := uid.Generate()
	salesPrice, _ := strconv.ParseFloat(in.SalesPrice, 64)
	productName := strings.TrimSpace(in.ProductName)
	if productName == "" {
		return nil, status.Error(codes.InvalidArgument, "产品名称不能为空")
	}
	color := normalizeProductColor(in.Color)
	colorNo, err := resolveColorNo(l.ctx, l.svcCtx.ProductModel, tenantId, productName, in.ColorNo)
	if err != nil {
		return nil, status.Error(codes.Internal, err.Error())
	}
	productCode := strings.ToUpper(strings.TrimSpace(in.ProductCode))
	if productCode == "" {
		productCode = generateProductCode(productName, colorNo)
	}
	if err := ensureProductCodeAvailable(l.ctx, l.svcCtx.ProductModel, tenantId, productCode); err != nil {
		return nil, status.Error(codes.AlreadyExists, err.Error())
	}
	if err := validateProductBatchInput(in.InitialBatch); err != nil {
		return nil, status.Error(codes.InvalidArgument, err.Error())
	}

	product := &model.InvProduct{
		ProductId:   productId,
		TenantId:    tenantId,
		ProductName: productName,
		ImageUrl:    in.ImageUrl,
		Spec:        in.Spec,
		Color:       color,
		ColorNo:     colorNo,
		ProductCode: productCode,
		SalesPrice:  salesPrice,
		Remark:      sql.NullString{String: in.Remark, Valid: in.Remark != ""},
		Status:      1,
	}

	_, err = l.svcCtx.ProductModel.Insert(l.ctx, product)
	if err != nil {
		return nil, status.Error(codes.Internal, err.Error())
	}

	firstBatchNo := productCode + "-B001"
	if batchNo := strings.TrimSpace(in.InitialBatch.GetBatchNo()); batchNo != "" {
		firstBatchNo = batchNo
	}

	firstBatch := &model.InvProductBatch{
		BatchId:   uid.Generate(),
		TenantId:  tenantId,
		ProductId: productId,
		BatchNo:   firstBatchNo,
		Status:    1,
	}
	if err := batchInputToModelFields(in.InitialBatch, firstBatch); err != nil {
		return nil, status.Error(codes.InvalidArgument, err.Error())
	}
	if _, err := l.svcCtx.ProductBatchModel.Insert(l.ctx, firstBatch); err != nil {
		return nil, status.Error(codes.Internal, err.Error())
	}

	var totalLengthM float64
	var totalBolts int

	if len(in.Pans) > 0 {
		pans := make([]*model.InvProductPan, 0, len(in.Pans))
		for i, panInput := range in.Pans {
			panId := uid.Generate()
			batchId := panInput.BatchId
			if batchId == "" {
				batchId = firstBatch.BatchId
			}
			if _, err := l.svcCtx.ProductBatchModel.FindOneByProductAndBatchId(l.ctx, tenantId, productId, batchId); err != nil {
				return nil, status.Error(codes.InvalidArgument, "批次不存在或不属于该产品")
			}
			pans = append(pans, &model.InvProductPan{
				PanId:     panId,
				ProductId: productId,
				BatchId:   batchId,
				Name:      panInput.Name,
				Position:  panInput.Position,
				SortOrder: int64(i + 1),
				TenantId:  tenantId,
			})

			if len(panInput.BoltLengths) > 0 {
				bolts := make([]*model.InvProductBolt, 0, len(panInput.BoltLengths))
				for j, lengthStr := range panInput.BoltLengths {
					lengthM, _ := strconv.ParseFloat(lengthStr, 64)
					totalLengthM += lengthM
					bolts = append(bolts, &model.InvProductBolt{
						BoltId:    uid.Generate(),
						PanId:     panId,
						LengthM:   lengthM,
						Color:     color,
						SortOrder: int64(j + 1),
						TenantId:  tenantId,
					})
				}
				totalBolts += len(panInput.BoltLengths)
				if err := l.svcCtx.BoltModel.BulkReplace(l.ctx, panId, tenantId, bolts); err != nil {
					l.Errorf("create bolts for pan %s failed: %v", panId, err)
				}
			}
		}
		if err := l.svcCtx.PanModel.BulkReplace(l.ctx, productId, tenantId, pans); err != nil {
			l.Errorf("create pans for product %s failed: %v", productId, err)
		}
	}

	metrics.ProductCreatedTotal.WithLabelValues(tenantId, productName, in.Spec, color).Inc()
	if totalLengthM > 0 {
		metrics.InboundLengthMetersTotal.WithLabelValues(tenantId, productName, color, "create").Add(totalLengthM)
	}
	if totalBolts > 0 {
		metrics.InboundBoltsTotal.WithLabelValues(tenantId, "create").Add(float64(totalBolts))
	}

	return &pb.IdResp{Id: productId}, nil
}