package service

import (
	"context"
	"fmt"

	"apskel-pos-be/internal/models"
	"apskel-pos-be/internal/processor"

	"github.com/google/uuid"
)

type HPPService interface {
	GetStandardHPP(ctx context.Context, req *models.StandardHPPRequest) (*models.StandardHPPResponse, error)
	GetRealHPP(ctx context.Context, req *models.RealHPPRequest) (*models.RealHPPResponse, error)
}

type HPPServiceImpl struct {
	hppProcessor processor.HPPProcessor
}

func NewHPPServiceImpl(hppProcessor processor.HPPProcessor) *HPPServiceImpl {
	return &HPPServiceImpl{
		hppProcessor: hppProcessor,
	}
}

func (s *HPPServiceImpl) GetStandardHPP(ctx context.Context, req *models.StandardHPPRequest) (*models.StandardHPPResponse, error) {
	if err := s.validateStandardHPPRequest(req); err != nil {
		return nil, fmt.Errorf("validation error: %w", err)
	}

	response, err := s.hppProcessor.GetStandardHPP(ctx, req)
	if err != nil {
		return nil, fmt.Errorf("failed to get standard HPP: %w", err)
	}

	return response, nil
}

func (s *HPPServiceImpl) GetRealHPP(ctx context.Context, req *models.RealHPPRequest) (*models.RealHPPResponse, error) {
	if err := s.validateRealHPPRequest(req); err != nil {
		return nil, fmt.Errorf("validation error: %w", err)
	}

	response, err := s.hppProcessor.GetRealHPP(ctx, req)
	if err != nil {
		return nil, fmt.Errorf("failed to get real HPP: %w", err)
	}

	return response, nil
}

func (s *HPPServiceImpl) validateStandardHPPRequest(req *models.StandardHPPRequest) error {
	if req.OrganizationID == uuid.Nil {
		return fmt.Errorf("organization_id is required")
	}
	return nil
}

func (s *HPPServiceImpl) validateRealHPPRequest(req *models.RealHPPRequest) error {
	if req.OrganizationID == uuid.Nil {
		return fmt.Errorf("organization_id is required")
	}
	if req.DateFrom.IsZero() {
		return fmt.Errorf("date_from is required")
	}
	if req.DateTo.IsZero() {
		return fmt.Errorf("date_to is required")
	}
	if req.DateFrom.After(req.DateTo) {
		return fmt.Errorf("date_from cannot be after date_to")
	}
	if req.GroupBy != "" && req.GroupBy != "hour" && req.GroupBy != "day" && req.GroupBy != "week" && req.GroupBy != "month" {
		return fmt.Errorf("invalid group_by value, must be one of: hour, day, week, month")
	}
	return nil
}