package repository

import (
	"context"
	"fmt"

	"apskel-pos-be/internal/entities"

	"gorm.io/gorm"
)

type CampaignRepository interface {
	Create(ctx context.Context, campaign *entities.Campaign) error
	GetByID(ctx context.Context, id string) (*entities.Campaign, error)
	List(ctx context.Context, req *entities.ListCampaignsRequest) ([]entities.Campaign, int64, error)
	Update(ctx context.Context, campaign *entities.Campaign) error
	Delete(ctx context.Context, id string) error
	GetActiveCampaigns(ctx context.Context) ([]entities.Campaign, error)
	GetCampaignsForApp(ctx context.Context) ([]entities.Campaign, error)
}

type campaignRepository struct {
	db *gorm.DB
}

func NewCampaignRepository(db *gorm.DB) CampaignRepository {
	return &campaignRepository{
		db: db,
	}
}

func (r *campaignRepository) Create(ctx context.Context, campaign *entities.Campaign) error {
	return r.db.WithContext(ctx).Create(campaign).Error
}

func (r *campaignRepository) GetByID(ctx context.Context, id string) (*entities.Campaign, error) {
	var campaign entities.Campaign
	if err := r.db.WithContext(ctx).Preload("Rules").Where("id = ?", id).First(&campaign).Error; err != nil {
		if err == gorm.ErrRecordNotFound {
			return nil, fmt.Errorf("campaign not found")
		}
		return nil, fmt.Errorf("failed to get campaign: %w", err)
	}
	return &campaign, nil
}

func (r *campaignRepository) List(ctx context.Context, req *entities.ListCampaignsRequest) ([]entities.Campaign, int64, error) {
	var campaigns []entities.Campaign
	var total int64

	query := r.db.WithContext(ctx).Model(&entities.Campaign{})

	// Apply filters
	if req.Search != "" {
		query = query.Where("name ILIKE ? OR description ILIKE ?", "%"+req.Search+"%", "%"+req.Search+"%")
	}

	if req.Type != "" {
		query = query.Where("type = ?", req.Type)
	}

	if req.IsActive != nil {
		query = query.Where("is_active = ?", *req.IsActive)
	}

	if req.ShowOnApp != nil {
		query = query.Where("show_on_app = ?", *req.ShowOnApp)
	}

	if req.StartDate != nil {
		query = query.Where("start_date >= ?", *req.StartDate)
	}

	if req.EndDate != nil {
		query = query.Where("end_date <= ?", *req.EndDate)
	}

	// Count total records
	if err := query.Count(&total).Error; err != nil {
		return nil, 0, fmt.Errorf("failed to count campaigns: %w", err)
	}

	// Apply pagination
	if req.Page > 0 && req.Limit > 0 {
		offset := (req.Page - 1) * req.Limit
		query = query.Offset(offset).Limit(req.Limit)
	}

	// Apply sorting
	query = query.Order("position ASC, created_at DESC")

	if err := query.Preload("Rules").Find(&campaigns).Error; err != nil {
		return nil, 0, fmt.Errorf("failed to list campaigns: %w", err)
	}

	return campaigns, total, nil
}

func (r *campaignRepository) Update(ctx context.Context, campaign *entities.Campaign) error {
	return r.db.WithContext(ctx).Save(campaign).Error
}

func (r *campaignRepository) Delete(ctx context.Context, id string) error {
	return r.db.WithContext(ctx).Transaction(func(tx *gorm.DB) error {
		// Delete campaign (rules will be deleted by CASCADE)
		if err := tx.Where("id = ?", id).Delete(&entities.Campaign{}).Error; err != nil {
			return fmt.Errorf("failed to delete campaign: %w", err)
		}
		return nil
	})
}

func (r *campaignRepository) GetActiveCampaigns(ctx context.Context) ([]entities.Campaign, error) {
	var campaigns []entities.Campaign
	now := "now()"
	if err := r.db.WithContext(ctx).Where("is_active = ? AND start_date <= ? AND end_date >= ?", true, now, now).Preload("Rules").Find(&campaigns).Error; err != nil {
		return nil, fmt.Errorf("failed to get active campaigns: %w", err)
	}
	return campaigns, nil
}

func (r *campaignRepository) GetCampaignsForApp(ctx context.Context) ([]entities.Campaign, error) {
	var campaigns []entities.Campaign
	now := "now()"
	if err := r.db.WithContext(ctx).Where("is_active = ? AND show_on_app = ? AND start_date <= ? AND end_date >= ?", true, true, now, now).Preload("Rules").Order("position ASC").Find(&campaigns).Error; err != nil {
		return nil, fmt.Errorf("failed to get campaigns for app: %w", err)
	}
	return campaigns, nil
}

// Campaign Rule Repository
type CampaignRuleRepository interface {
	Create(ctx context.Context, rule *entities.CampaignRule) error
	GetByID(ctx context.Context, id string) (*entities.CampaignRule, error)
	List(ctx context.Context, req *entities.ListCampaignRulesRequest) ([]entities.CampaignRule, int64, error)
	Update(ctx context.Context, rule *entities.CampaignRule) error
	Delete(ctx context.Context, id string) error
	GetByCampaignID(ctx context.Context, campaignID string) ([]entities.CampaignRule, error)
}

type campaignRuleRepository struct {
	db *gorm.DB
}

func NewCampaignRuleRepository(db *gorm.DB) CampaignRuleRepository {
	return &campaignRuleRepository{
		db: db,
	}
}

func (r *campaignRuleRepository) Create(ctx context.Context, rule *entities.CampaignRule) error {
	if err := r.db.WithContext(ctx).Create(rule).Error; err != nil {
		return fmt.Errorf("failed to create campaign rule: %w", err)
	}
	return nil
}

func (r *campaignRuleRepository) GetByID(ctx context.Context, id string) (*entities.CampaignRule, error) {
	var rule entities.CampaignRule
	if err := r.db.WithContext(ctx).Where("id = ?", id).First(&rule).Error; err != nil {
		if err == gorm.ErrRecordNotFound {
			return nil, fmt.Errorf("campaign rule not found")
		}
		return nil, fmt.Errorf("failed to get campaign rule: %w", err)
	}
	return &rule, nil
}

func (r *campaignRuleRepository) List(ctx context.Context, req *entities.ListCampaignRulesRequest) ([]entities.CampaignRule, int64, error) {
	var rules []entities.CampaignRule
	var total int64

	query := r.db.WithContext(ctx).Model(&entities.CampaignRule{})

	// Apply filters
	if req.CampaignID != "" {
		query = query.Where("campaign_id = ?", req.CampaignID)
	}

	if req.RuleType != "" {
		query = query.Where("rule_type = ?", req.RuleType)
	}

	if req.RewardType != "" {
		query = query.Where("reward_type = ?", req.RewardType)
	}

	// Count total records
	if err := query.Count(&total).Error; err != nil {
		return nil, 0, fmt.Errorf("failed to count campaign rules: %w", err)
	}

	// Apply pagination
	if req.Page > 0 && req.Limit > 0 {
		offset := (req.Page - 1) * req.Limit
		query = query.Offset(offset).Limit(req.Limit)
	}

	// Apply sorting
	query = query.Order("created_at DESC")

	if err := query.Find(&rules).Error; err != nil {
		return nil, 0, fmt.Errorf("failed to list campaign rules: %w", err)
	}

	return rules, total, nil
}

func (r *campaignRuleRepository) Update(ctx context.Context, rule *entities.CampaignRule) error {
	if err := r.db.WithContext(ctx).Save(rule).Error; err != nil {
		return fmt.Errorf("failed to update campaign rule: %w", err)
	}
	return nil
}

func (r *campaignRuleRepository) Delete(ctx context.Context, id string) error {
	if err := r.db.WithContext(ctx).Where("id = ?", id).Delete(&entities.CampaignRule{}).Error; err != nil {
		return fmt.Errorf("failed to delete campaign rule: %w", err)
	}
	return nil
}

func (r *campaignRuleRepository) GetByCampaignID(ctx context.Context, campaignID string) ([]entities.CampaignRule, error) {
	var rules []entities.CampaignRule
	if err := r.db.WithContext(ctx).Where("campaign_id = ?", campaignID).Find(&rules).Error; err != nil {
		return nil, fmt.Errorf("failed to get campaign rules by campaign ID: %w", err)
	}
	return rules, nil
}