package logic

import (
	"context"
	"errors"
	"strconv"

	"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 SavePansLogic struct {
	ctx    context.Context
	svcCtx *svc.ServiceContext
	logx.Logger
}

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

func (l *SavePansLogic) SavePans(in *pb.SavePansReq) (*pb.Empty, error) {
	tenantId := tenantctx.ExtractTenantId(l.ctx)

	product, err := l.svcCtx.ProductModel.FindOneByProductId(l.ctx, in.ProductId)
	if err != nil || product.TenantId != tenantId {
		return nil, status.Error(codes.NotFound, "product not found")
	}

	defaultBatch, err := l.svcCtx.ProductBatchModel.FindLatestByProductId(l.ctx, tenantId, in.ProductId)
	if err != nil {
		if !errors.Is(err, model.ErrNotFound) {
			return nil, status.Error(codes.Internal, err.Error())
		}
		defaultBatch = &model.InvProductBatch{
			BatchId:   uid.Generate(),
			TenantId:  tenantId,
			ProductId: in.ProductId,
			BatchNo:   product.ProductCode + "-B001",
			Status:    1,
		}
		if err := batchInputToModelFields(nil, defaultBatch); err != nil {
			return nil, status.Error(codes.InvalidArgument, err.Error())
		}
		if _, err := l.svcCtx.ProductBatchModel.Insert(l.ctx, defaultBatch); err != nil {
			return nil, status.Error(codes.Internal, err.Error())
		}
	}

	var totalLengthM float64
	var totalBolts int
	type panBoltSet struct {
		panId string
		bolts []*model.InvProductBolt
	}
	boltsByPan := make([]panBoltSet, 0, len(in.Pans))

	pans := make([]*model.InvProductPan, 0, len(in.Pans))
	for i, panInput := range in.Pans {
		panId := uid.Generate()
		batchId := panInput.BatchId
		if batchId == "" {
			batchId = defaultBatch.BatchId
		}
		if _, err := l.svcCtx.ProductBatchModel.FindOneByProductAndBatchId(l.ctx, tenantId, in.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: in.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:     product.Color,
					SortOrder: int64(j + 1),
					TenantId:  tenantId,
				})
			}
			totalBolts += len(panInput.BoltLengths)
			boltsByPan = append(boltsByPan, panBoltSet{panId: panId, bolts: bolts})
		}
	}

	if err := l.svcCtx.BoltModel.DeleteByProductId(l.ctx, in.ProductId); err != nil {
		return nil, status.Error(codes.Internal, err.Error())
	}

	if err := l.svcCtx.PanModel.BulkReplace(l.ctx, in.ProductId, tenantId, pans); err != nil {
		return nil, status.Error(codes.Internal, err.Error())
	}

	for _, item := range boltsByPan {
		if err := l.svcCtx.BoltModel.BulkReplace(l.ctx, item.panId, tenantId, item.bolts); err != nil {
			return nil, status.Error(codes.Internal, err.Error())
		}
	}

	metrics.PansSavedTotal.WithLabelValues(tenantId, in.ProductId).Inc()
	if totalLengthM > 0 {
		productName := l.resolveProductName(in.ProductId)
		color := l.resolveProductColor(in.ProductId)
		metrics.InboundLengthMetersTotal.WithLabelValues(tenantId, productName, color, "save_pans").Add(totalLengthM)
	}
	if totalBolts > 0 {
		metrics.InboundBoltsTotal.WithLabelValues(tenantId, "save_pans").Add(float64(totalBolts))
	}

	return &pb.Empty{}, nil
}

func (l *SavePansLogic) resolveProductName(productId string) string {
	p, err := l.svcCtx.ProductModel.FindOneByProductId(l.ctx, productId)
	if err != nil {
		return "unknown"
	}
	return p.ProductName
}

func (l *SavePansLogic) resolveProductColor(productId string) string {
	p, err := l.svcCtx.ProductModel.FindOneByProductId(l.ctx, productId)
	if err != nil {
		return "unknown"
	}
	return p.Color
}