package service

import (
	"gitlab.com/mbugroup/lti-api.git/internal/modules/repports/dto"
	repportRepo "gitlab.com/mbugroup/lti-api.git/internal/modules/repports/repositories"
	validation "gitlab.com/mbugroup/lti-api.git/internal/modules/repports/validations"
	"gitlab.com/mbugroup/lti-api.git/internal/utils"

	approvalService "gitlab.com/mbugroup/lti-api.git/internal/common/service"
	approvalDTO "gitlab.com/mbugroup/lti-api.git/internal/modules/approvals/dto"
	expenseRepo "gitlab.com/mbugroup/lti-api.git/internal/modules/expenses/repositories"
	marketingRepo "gitlab.com/mbugroup/lti-api.git/internal/modules/marketing/repositories"

	entity "gitlab.com/mbugroup/lti-api.git/internal/entities"

	"github.com/go-playground/validator/v10"
	"github.com/gofiber/fiber/v2"
	"github.com/sirupsen/logrus"
	"gorm.io/gorm"
)

type RepportService interface {
	GetExpense(ctx *fiber.Ctx, params *validation.ExpenseQuery) ([]dto.RepportExpenseListDTO, int64, error)
	GetMarketing(ctx *fiber.Ctx, params *validation.MarketingQuery) ([]dto.RepportMarketingListDTO, int64, error)
	GetPurchaseSupplier(ctx *fiber.Ctx, params *validation.PurchaseSupplierQuery) ([]dto.PurchaseSupplierDTO, int64, error)
}

type repportService struct {
	Log                    *logrus.Logger
	Validate               *validator.Validate
	ExpenseRealizationRepo expenseRepo.ExpenseRealizationRepository
	MarketingDeliveryRepo  marketingRepo.MarketingDeliveryProductRepository
	ApprovalSvc            approvalService.ApprovalService
	PurchaseSupplierRepo   repportRepo.PurchaseSupplierRepository
}

func NewRepportService(
	validate *validator.Validate,
	expenseRealizationRepo expenseRepo.ExpenseRealizationRepository,
	marketingDeliveryRepo marketingRepo.MarketingDeliveryProductRepository,
	approvalSvc approvalService.ApprovalService,
	purchaseSupplierRepo repportRepo.PurchaseSupplierRepository,
) RepportService {
	return &repportService{
		Log:                    utils.Log,
		Validate:               validate,
		ExpenseRealizationRepo: expenseRealizationRepo,
		MarketingDeliveryRepo:  marketingDeliveryRepo,
		ApprovalSvc:            approvalSvc,
		PurchaseSupplierRepo:   purchaseSupplierRepo,
	}
}

func (s *repportService) GetExpense(c *fiber.Ctx, params *validation.ExpenseQuery) ([]dto.RepportExpenseListDTO, int64, error) {
	if err := s.Validate.Struct(params); err != nil {
		return nil, 0, err
	}

	offset := (params.Page - 1) * params.Limit

	realizations, total, err := s.ExpenseRealizationRepo.GetAllWithFilters(c.Context(), offset, params.Limit, params)
	if err != nil {
		s.Log.Errorf("GetAllWithFilters error: %v", err)
		return nil, 0, err
	}

	result := dto.ToRepportExpenseListDTOs(realizations)

	expenseIDs := make([]uint, 0, len(result))
	for i := range result {
		expenseIDs = append(expenseIDs, uint(result[i].Id))
	}

	approvals, err := s.ApprovalSvc.LatestByTargets(c.Context(), utils.ApprovalWorkflowExpense, expenseIDs, func(db *gorm.DB) *gorm.DB {
		return db.Preload("ActionUser")
	})
	if err != nil {
		s.Log.Warnf("LatestByTargets error: %v", err)
	}

	for i := range result {
		expenseIDAsUint := uint(result[i].Id)
		if approval, exists := approvals[expenseIDAsUint]; exists && approval != nil {
			mapped := approvalDTO.ToApprovalDTO(*approval)
			result[i].LatestApproval = &mapped
		}
	}

	return result, total, nil
}

func (s *repportService) GetMarketing(c *fiber.Ctx, params *validation.MarketingQuery) ([]dto.RepportMarketingListDTO, int64, error) {
	if err := s.Validate.Struct(params); err != nil {
		return nil, 0, err
	}

	offset := (params.Page - 1) * params.Limit

	deliveryProducts, total, err := s.MarketingDeliveryRepo.GetAllWithFilters(c.Context(), offset, params.Limit, params)
	if err != nil {
		return nil, 0, err
	}

	marketingIDMap := make(map[uint]bool)
	marketingIDs := make([]uint, 0)
	for _, dp := range deliveryProducts {
		if marketingID := dp.MarketingProduct.Marketing.Id; marketingID > 0 && !marketingIDMap[marketingID] {
			marketingIDs = append(marketingIDs, marketingID)
			marketingIDMap[marketingID] = true
		}
	}

	approvals, err := s.ApprovalSvc.LatestByTargets(c.Context(), utils.ApprovalWorkflowMarketing, marketingIDs, func(db *gorm.DB) *gorm.DB {
		return db.Preload("ActionUser")
	})
	if err != nil {
		s.Log.Warnf("LatestByTargets error: %v", err)
	}

	for i := range deliveryProducts {
		if approval, exists := approvals[deliveryProducts[i].MarketingProduct.Marketing.Id]; exists && approval != nil {
			deliveryProducts[i].MarketingProduct.Marketing.LatestApproval = approval
		}
	}

	return dto.ToRepportMarketingListDTOs(deliveryProducts), total, nil
}

func (s *repportService) GetPurchaseSupplier(c *fiber.Ctx, params *validation.PurchaseSupplierQuery) ([]dto.PurchaseSupplierDTO, int64, error) {
	if err := s.Validate.Struct(params); err != nil {
		return nil, 0, err
	}

	offset := (params.Page - 1) * params.Limit
	if offset < 0 {
		offset = 0
	}

	suppliers, totalSuppliers, err := s.PurchaseSupplierRepo.GetSuppliersWithPurchases(c.Context(), offset, params.Limit, params)
	if err != nil {
		return nil, 0, err
	}

	if totalSuppliers == 0 || len(suppliers) == 0 {
		return []dto.PurchaseSupplierDTO{}, totalSuppliers, nil
	}

	supplierMap := make(map[uint]entity.Supplier, len(suppliers))
	supplierIDs := make([]uint, 0, len(suppliers))
	for _, supplier := range suppliers {
		supplierMap[supplier.Id] = supplier
		supplierIDs = append(supplierIDs, supplier.Id)
	}

	items, err := s.PurchaseSupplierRepo.GetItemsBySuppliers(c.Context(), supplierIDs, params)
	if err != nil {
		return nil, 0, err
	}

	itemsBySupplier := make(map[uint][]entity.PurchaseItem)
	for _, item := range items {
		if item.Purchase == nil {
			continue
		}
		supplierID := item.Purchase.SupplierId
		itemsBySupplier[supplierID] = append(itemsBySupplier[supplierID], item)
	}

	result := make([]dto.PurchaseSupplierDTO, 0, len(supplierIDs))
	for _, supplierID := range supplierIDs {
		supplier, exists := supplierMap[supplierID]
		if !exists {
			continue
		}

		supplierItems := itemsBySupplier[supplierID]
		dtoItem := dto.ToPurchaseSupplierDTO(supplier, supplierItems)
		result = append(result, dtoItem)
	}

	return result, totalSuppliers, nil
}