package repository

import (
	"context"
	"time"

	"apskel-pos-be/internal/entities"

	"github.com/google/uuid"
	"gorm.io/gorm"
)

type HPPRepository interface {
	GetStandardHPP(ctx context.Context, organizationID uuid.UUID, productID *uuid.UUID, categoryID *uuid.UUID) ([]*entities.StandardHPPProduct, error)
	GetStandardHPPIngredients(ctx context.Context, organizationID uuid.UUID, productIDs []uuid.UUID) ([]*entities.StandardHPPIngredient, error)
	GetRealHPP(ctx context.Context, organizationID uuid.UUID, outletID *uuid.UUID, productID *uuid.UUID, categoryID *uuid.UUID, dateFrom, dateTo time.Time) ([]*entities.RealHPPProduct, error)
	GetRealHPPTimeSeries(ctx context.Context, organizationID uuid.UUID, outletID *uuid.UUID, productID *uuid.UUID, categoryID *uuid.UUID, dateFrom, dateTo time.Time, groupBy string) ([]*entities.RealHPPTimeSeries, error)
}

type HPPRepositoryImpl struct {
	db *gorm.DB
}

func NewHPPRepositoryImpl(db *gorm.DB) *HPPRepositoryImpl {
	return &HPPRepositoryImpl{db: db}
}

func (r *HPPRepositoryImpl) GetStandardHPP(ctx context.Context, organizationID uuid.UUID, productID *uuid.UUID, categoryID *uuid.UUID) ([]*entities.StandardHPPProduct, error) {
	var results []*entities.StandardHPPProduct

	query := r.db.WithContext(ctx).
		Table("products p").
		Select(`
			p.id as product_id,
			p.name as product_name,
			COALESCE(p.sku, '') as product_sku,
			c.id as category_id,
			c.name as category_name,
			p.price as selling_price,
			p.cost as product_cost,
			COALESCE(SUM(
				pr.quantity * i.cost * (1 + COALESCE(pr.waste_percentage, 0) / 100.0)
			), 0) as standard_cost,
			CASE 
				WHEN p.price > 0 
				THEN COALESCE(SUM(pr.quantity * i.cost * (1 + COALESCE(pr.waste_percentage, 0) / 100.0)), 0) / p.price * 100 
				ELSE 0 
			END as standard_hpp_percentage,
			CASE WHEN COUNT(pr.id) > 0 THEN true ELSE false END as has_recipe
		`).
		Joins("LEFT JOIN product_recipes pr ON pr.product_id = p.id AND pr.organization_id = ?", organizationID).
		Joins("LEFT JOIN ingredients i ON pr.ingredient_id = i.id").
		Joins("JOIN categories c ON p.category_id = c.id").
		Where("p.organization_id = ?", organizationID).
		Where("p.is_active = ?", true)

	if productID != nil {
		query = query.Where("p.id = ?", *productID)
	}
	if categoryID != nil {
		query = query.Where("p.category_id = ?", *categoryID)
	}

	err := query.
		Group("p.id, p.name, p.sku, c.id, c.name, p.price, p.cost").
		Order("p.name ASC").
		Scan(&results).Error

	return results, err
}

func (r *HPPRepositoryImpl) GetStandardHPPIngredients(ctx context.Context, organizationID uuid.UUID, productIDs []uuid.UUID) ([]*entities.StandardHPPIngredient, error) {
	if len(productIDs) == 0 {
		return []*entities.StandardHPPIngredient{}, nil
	}

	var results []*entities.StandardHPPIngredient

	err := r.db.WithContext(ctx).
		Table("product_recipes pr").
		Select(`
			pr.product_id,
			pr.ingredient_id,
			i.name as ingredient_name,
			pr.quantity,
			COALESCE(u.name, '') as unit_name,
			i.cost as cost_per_unit,
			COALESCE(pr.waste_percentage, 0) as waste_percentage,
			pr.quantity * i.cost * (1 + COALESCE(pr.waste_percentage, 0) / 100.0) as total_cost
		`).
		Joins("JOIN ingredients i ON pr.ingredient_id = i.id").
		Joins("LEFT JOIN units u ON i.unit_id = u.id").
		Where("pr.organization_id = ?", organizationID).
		Where("pr.product_id IN ?", productIDs).
		Order("pr.product_id, i.name").
		Scan(&results).Error

	return results, err
}

func (r *HPPRepositoryImpl) GetRealHPP(ctx context.Context, organizationID uuid.UUID, outletID *uuid.UUID, productID *uuid.UUID, categoryID *uuid.UUID, dateFrom, dateTo time.Time) ([]*entities.RealHPPProduct, error) {
	var results []*entities.RealHPPProduct

	query := r.db.WithContext(ctx).
		Table("products p").
		Select(`
			p.id as product_id,
			p.name as product_name,
			COALESCE(p.sku, '') as product_sku,
			c.id as category_id,
			c.name as category_name,
			p.price as selling_price,
			COALESCE(SUM(
				CASE WHEN oi.is_fully_refunded = false 
				THEN oi.unit_cost * (oi.quantity - COALESCE(oi.refund_quantity, 0))
				ELSE 0 END
			), 0) as real_total_cost,
			COALESCE(SUM(
				CASE WHEN oi.is_fully_refunded = false 
				THEN oi.total_price - COALESCE(oi.refund_amount, 0)
				ELSE 0 END
			), 0) as real_total_revenue,
			CASE 
				WHEN COALESCE(SUM(
					CASE WHEN oi.is_fully_refunded = false 
					THEN oi.total_price - COALESCE(oi.refund_amount, 0)
					ELSE 0 END
				), 0) > 0 
				THEN COALESCE(SUM(
					CASE WHEN oi.is_fully_refunded = false 
					THEN oi.unit_cost * (oi.quantity - COALESCE(oi.refund_quantity, 0))
					ELSE 0 END
				), 0) / COALESCE(SUM(
					CASE WHEN oi.is_fully_refunded = false 
					THEN oi.total_price - COALESCE(oi.refund_amount, 0)
					ELSE 0 END
				), 0) * 100 
				ELSE 0 
			END as real_hpp_percentage,
			COALESCE(SUM(
				CASE WHEN oi.is_fully_refunded = false 
				THEN oi.quantity - COALESCE(oi.refund_quantity, 0)
				ELSE 0 END
			), 0) as total_quantity_sold,
			COALESCE(COUNT(DISTINCT oi.order_id), 0) as total_orders
		`).
		Joins("JOIN categories c ON p.category_id = c.id").
		Joins("LEFT JOIN order_items oi ON oi.product_id = p.id AND oi.status != 'cancelled'").
		Joins("LEFT JOIN orders o ON oi.order_id = o.id AND o.is_void = false AND o.is_refund = false AND o.status = 'completed' AND o.payment_status = 'completed' AND o.organization_id = ? AND o.created_at >= ? AND o.created_at <= ?", organizationID, dateFrom, dateTo).
		Where("p.organization_id = ?", organizationID).
		Where("p.is_active = ?", true)

	if outletID != nil {
		query = query.Where("o.outlet_id = ? OR o.id IS NULL", *outletID)
	}
	if productID != nil {
		query = query.Where("p.id = ?", *productID)
	}
	if categoryID != nil {
		query = query.Where("p.category_id = ?", *categoryID)
	}

	err := query.
		Group("p.id, p.name, p.sku, c.id, c.name, p.price").
		Order("p.name ASC").
		Scan(&results).Error

	return results, err
}

func (r *HPPRepositoryImpl) GetRealHPPTimeSeries(ctx context.Context, organizationID uuid.UUID, outletID *uuid.UUID, productID *uuid.UUID, categoryID *uuid.UUID, dateFrom, dateTo time.Time, groupBy string) ([]*entities.RealHPPTimeSeries, error) {
	var results []*entities.RealHPPTimeSeries

	var timeFormat string
	switch groupBy {
	case "hour":
		timeFormat = "DATE_TRUNC('hour', o.created_at)"
	case "week":
		timeFormat = "DATE_TRUNC('week', o.created_at)"
	case "month":
		timeFormat = "DATE_TRUNC('month', o.created_at)"
	default:
		timeFormat = "DATE_TRUNC('day', o.created_at)"
	}

	query := r.db.WithContext(ctx).
		Table("orders o").
		Select(`
			`+timeFormat+` as date,
			COALESCE(SUM(
				oi.unit_cost * (oi.quantity - COALESCE(oi.refund_quantity, 0))
			), 0) as real_total_cost,
			COALESCE(SUM(
				oi.total_price - COALESCE(oi.refund_amount, 0)
			), 0) as real_total_revenue,
			CASE 
				WHEN COALESCE(SUM(oi.total_price - COALESCE(oi.refund_amount, 0)), 0) > 0 
				THEN COALESCE(SUM(oi.unit_cost * (oi.quantity - COALESCE(oi.refund_quantity, 0))), 0) / COALESCE(SUM(oi.total_price - COALESCE(oi.refund_amount, 0)), 0) * 100 
				ELSE 0 
			END as real_hpp_percentage,
			COUNT(DISTINCT o.id) as total_orders
		`).
		Joins("JOIN order_items oi ON oi.order_id = o.id AND oi.status != 'cancelled' AND oi.is_fully_refunded = false").
		Where("o.organization_id = ?", organizationID).
		Where("o.is_void = false").
		Where("o.is_refund = false").
		Where("o.status = 'completed'").
		Where("o.payment_status = 'completed'").
		Where("o.created_at >= ? AND o.created_at <= ?", dateFrom, dateTo)

	if outletID != nil {
		query = query.Where("o.outlet_id = ?", *outletID)
	}
	if productID != nil {
		query = query.Where("oi.product_id = ?", *productID)
	}
	if categoryID != nil {
		query = query.Where("oi.product_id IN (SELECT id FROM products WHERE category_id = ?)", *categoryID)
	}

	err := query.
		Group(timeFormat).
		Order(timeFormat).
		Scan(&results).Error

	return results, err
}