package service

import (
	"context"
	"database/sql"
	"time"

	"github.com/google/uuid"
	"github.com/muyuqingfeng/iloom/shared/pkg/database"
	"github.com/muyuqingfeng/iloom/textile-service/internal/model"
	"github.com/muyuqingfeng/iloom/textile-service/internal/repository"
)

type CreateYarnStockRequest struct {
	Name     string  `json:"name"`
	Spec     string  `json:"spec"`
	Quantity float64 `json:"quantity"`
	Unit     string  `json:"unit"`
	MinStock float64 `json:"min_stock"`
}

type UpdateYarnStockRequest struct {
	Name     string  `json:"name"`
	Spec     string  `json:"spec"`
	Unit     string  `json:"unit"`
	MinStock float64 `json:"min_stock"`
}

type YarnRecordRequest struct {
	RecordType string  `json:"record_type"`
	Quantity   float64 `json:"quantity"`
	Unit       string  `json:"unit"`
	BatchNo    string  `json:"batch_no"`
	PlanID     string  `json:"plan_id"`
	Notes      string  `json:"notes"`
}

type YarnService struct {
	repo *repository.YarnRepo
	db   *sql.DB
}

func NewYarnService(repo *repository.YarnRepo, db *sql.DB) *YarnService {
	return &YarnService{repo: repo, db: db}
}

func (s *YarnService) List(ctx context.Context, companyID string) ([]model.YarnStock, error) {
	return s.repo.List(ctx, companyID)
}

func (s *YarnService) Create(ctx context.Context, companyID string, req CreateYarnStockRequest) (*model.YarnStock, error) {
	var spec *string
	if req.Spec != "" {
		spec = &req.Spec
	}

	unit := req.Unit
	if unit == "" {
		unit = "kg"
	}

	stock := &model.YarnStock{
		ID:        uuid.New().String(),
		CompanyID: companyID,
		Name:      req.Name,
		Spec:      spec,
		Quantity:  req.Quantity,
		Unit:      unit,
		MinStock:  req.MinStock,
		UpdatedAt: time.Now(),
	}

	if err := s.repo.Create(ctx, stock); err != nil {
		return nil, err
	}
	return stock, nil
}

func (s *YarnService) Update(ctx context.Context, id, companyID string, req UpdateYarnStockRequest) error {
	var spec *string
	if req.Spec != "" {
		spec = &req.Spec
	}

	stock := &model.YarnStock{
		ID:        id,
		CompanyID: companyID,
		Name:      req.Name,
		Spec:      spec,
		Unit:      req.Unit,
		MinStock:  req.MinStock,
		UpdatedAt: time.Now(),
	}
	return s.repo.Update(ctx, stock)
}

func (s *YarnService) AddRecord(ctx context.Context, yarnStockID, companyID, userID string, req YarnRecordRequest) error {
	return database.WithTx(ctx, s.db, func(tx *sql.Tx) error {
		var batchNo, planID, notes, operatorID *string
		if req.BatchNo != "" {
			batchNo = &req.BatchNo
		}
		if req.PlanID != "" {
			planID = &req.PlanID
		}
		if req.Notes != "" {
			notes = &req.Notes
		}
		if userID != "" {
			operatorID = &userID
		}

		unit := req.Unit
		if unit == "" {
			unit = "kg"
		}

		rec := &model.YarnStockRecord{
			ID:          uuid.New().String(),
			YarnStockID: &yarnStockID,
			CompanyID:   companyID,
			RecordType:  req.RecordType,
			Quantity:    req.Quantity,
			Unit:        unit,
			BatchNo:     batchNo,
			PlanID:      planID,
			Notes:       notes,
			OperatorID:  operatorID,
			CreatedAt:   time.Now(),
		}

		if err := s.repo.CreateRecord(ctx, tx, rec); err != nil {
			return err
		}

		delta := req.Quantity
		if req.RecordType == "out" {
			delta = -delta
		}
		return s.repo.UpdateQuantity(ctx, tx, yarnStockID, delta)
	})
}