package processor

import (
	"context"
	"fmt"

	"apskel-pos-be/internal/contract"
	"apskel-pos-be/internal/entities"
	"apskel-pos-be/internal/mappers"
	"apskel-pos-be/internal/models"
	"apskel-pos-be/internal/repository"
)

type RewardProcessor interface {
	CreateReward(ctx context.Context, req *contract.CreateRewardRequest) (*models.RewardResponse, error)
	GetReward(ctx context.Context, id string) (*models.RewardResponse, error)
	ListRewards(ctx context.Context, req *contract.ListRewardsRequest) (*models.ListRewardsResponse, error)
	UpdateReward(ctx context.Context, req *contract.UpdateRewardRequest) (*models.RewardResponse, error)
	DeleteReward(ctx context.Context, id string) error
	UpdateRewardStock(ctx context.Context, id string, newStock int) error
	GetRewardsByType(ctx context.Context, rewardType string) ([]models.RewardResponse, error)
}

type rewardProcessor struct {
	rewardRepo repository.RewardRepository
}

func NewRewardProcessor(rewardRepo repository.RewardRepository) RewardProcessor {
	return &rewardProcessor{
		rewardRepo: rewardRepo,
	}
}

func (p *rewardProcessor) CreateReward(ctx context.Context, req *contract.CreateRewardRequest) (*models.RewardResponse, error) {
	// Convert request to entity
	entity := mappers.ToRewardEntity(req)
	if entity == nil {
		return nil, fmt.Errorf("invalid request data")
	}

	// Create in repository
	if err := p.rewardRepo.Create(ctx, entity); err != nil {
		return nil, fmt.Errorf("failed to create reward: %w", err)
	}

	// Convert entity to response
	response := mappers.ToRewardResponse(entity)
	return response, nil
}

func (p *rewardProcessor) GetReward(ctx context.Context, id string) (*models.RewardResponse, error) {
	// Get from repository
	entity, err := p.rewardRepo.GetByID(ctx, id)
	if err != nil {
		return nil, fmt.Errorf("failed to get reward: %w", err)
	}

	if entity == nil {
		return nil, fmt.Errorf("reward not found")
	}

	// Convert entity to response
	response := mappers.ToRewardResponse(entity)
	return response, nil
}

func (p *rewardProcessor) ListRewards(ctx context.Context, req *contract.ListRewardsRequest) (*models.ListRewardsResponse, error) {
	// Convert request to entity request
	entityReq := &entities.ListRewardsRequest{
		Page:       req.Page,
		Limit:      req.Limit,
		Search:     req.Search,
		RewardType: req.RewardType,
		MinPoints:  req.MinPoints,
		MaxPoints:  req.MaxPoints,
		HasStock:   req.HasStock,
	}

	// Get from repository
	entities, total, err := p.rewardRepo.List(ctx, entityReq)
	if err != nil {
		return nil, fmt.Errorf("failed to list rewards: %w", err)
	}

	// Convert entities to response
	rewards := mappers.ToRewardResponseSlice(entities)

	response := &models.ListRewardsResponse{
		Rewards: rewards,
		Total:   total,
		Page:    req.Page,
		Limit:   req.Limit,
	}

	return response, nil
}

func (p *rewardProcessor) UpdateReward(ctx context.Context, req *contract.UpdateRewardRequest) (*models.RewardResponse, error) {
	// Convert request to entity
	entity := mappers.ToRewardEntityFromUpdate(req)
	if entity == nil {
		return nil, fmt.Errorf("invalid request data")
	}

	// Update in repository
	if err := p.rewardRepo.Update(ctx, entity); err != nil {
		return nil, fmt.Errorf("failed to update reward: %w", err)
	}

	// Get updated entity
	updatedEntity, err := p.rewardRepo.GetByID(ctx, req.ID.String())
	if err != nil {
		return nil, fmt.Errorf("failed to get updated reward: %w", err)
	}

	// Convert entity to response
	response := mappers.ToRewardResponse(updatedEntity)
	return response, nil
}

func (p *rewardProcessor) DeleteReward(ctx context.Context, id string) error {
	// Delete from repository
	if err := p.rewardRepo.Delete(ctx, id); err != nil {
		return fmt.Errorf("failed to delete reward: %w", err)
	}

	return nil
}

func (p *rewardProcessor) UpdateRewardStock(ctx context.Context, id string, newStock int) error {
	// Update stock in repository
	if err := p.rewardRepo.UpdateStock(ctx, id, newStock); err != nil {
		return fmt.Errorf("failed to update reward stock: %w", err)
	}

	return nil
}

func (p *rewardProcessor) GetRewardsByType(ctx context.Context, rewardType string) ([]models.RewardResponse, error) {
	// Get from repository
	entities, err := p.rewardRepo.GetByRewardType(ctx, entities.RewardType(rewardType))
	if err != nil {
		return nil, fmt.Errorf("failed to get rewards by type: %w", err)
	}

	// Convert entities to response
	rewards := mappers.ToRewardResponseSlice(entities)
	return rewards, nil
}