package repository

import (
	"errors"
	"fmt"

	"accounting-app/internal/models"

	"gorm.io/gorm"
)

// Common user settings repository errors
var (
	ErrUserSettingsNotFound = errors.New("user settings not found")
)

// UserSettingsRepository handles database operations for user settings
type UserSettingsRepository struct {
	db *gorm.DB
}

// NewUserSettingsRepository creates a new UserSettingsRepository instance
func NewUserSettingsRepository(db *gorm.DB) *UserSettingsRepository {
	return &UserSettingsRepository{db: db}
}

// GetOrCreate retrieves user settings or creates default settings if not found
func (r *UserSettingsRepository) GetOrCreate(userID uint) (*models.UserSettings, error) {
	var settings models.UserSettings

	// Try to get existing settings
	err := r.db.Where("user_id = ?", userID).First(&settings).Error
	if err != nil {
		if errors.Is(err, gorm.ErrRecordNotFound) {
			// Create default settings
			settings = models.UserSettings{
				UserID:               &userID,
				PreciseTimeEnabled:   true,
				IconLayout:           string(models.IconLayoutFive),
				ImageCompression:     string(models.ImageCompressionMedium),
				ShowReimbursementBtn: true,
				ShowRefundBtn:        true,
				CurrentLedgerID:      nil,
			}

			if err := r.db.Create(&settings).Error; err != nil {
				return nil, fmt.Errorf("failed to create default settings: %w", err)
			}

			return &settings, nil
		}
		return nil, fmt.Errorf("failed to get settings: %w", err)
	}

	return &settings, nil
}

// Update updates existing user settings
func (r *UserSettingsRepository) Update(settings *models.UserSettings) error {
	if err := r.db.Save(settings).Error; err != nil {
		return fmt.Errorf("failed to update settings: %w", err)
	}
	return nil
}

// GetWithDefaultAccounts retrieves user settings with preloaded default account relationships
// Feature: financial-core-upgrade
// Validates: Requirements 5.1, 5.2
// GetWithDefaultAccounts retrieves user settings with preloaded default account relationships
// Feature: financial-core-upgrade
// Validates: Requirements 5.1, 5.2
func (r *UserSettingsRepository) GetWithDefaultAccounts(userID uint) (*models.UserSettings, error) {
	var settings models.UserSettings

	err := r.db.Where("user_id = ?", userID).
		Preload("DefaultExpenseAccount").
		Preload("DefaultIncomeAccount").
		First(&settings).Error

	if err != nil {
		if errors.Is(err, gorm.ErrRecordNotFound) {
			// Create default settings
			settings = models.UserSettings{
				UserID:               &userID,
				PreciseTimeEnabled:   true,
				IconLayout:           string(models.IconLayoutFive),
				ImageCompression:     string(models.ImageCompressionMedium),
				ShowReimbursementBtn: true,
				ShowRefundBtn:        true,
				CurrentLedgerID:      nil,
			}

			if err := r.db.Create(&settings).Error; err != nil {
				return nil, fmt.Errorf("failed to create default settings: %w", err)
			}

			return &settings, nil
		}
		return nil, fmt.Errorf("failed to get settings with default accounts: %w", err)
	}

	return &settings, nil
}