package classes

import (
	"context"
	"fmt"

	"gorm.io/gorm"
)

// UserGroupCodes returns the codes of the user's groups ordered by
// user_groups.id; groups without a code are skipped. A user in no group
// gets an empty slice.
func UserGroupCodes(ctx context.Context, db *gorm.DB, userID uint) ([]string, error) {
	if db == nil {
		return nil, fmt.Errorf("golem15.user: gorm handle is missing")
	}
	codes := []string{}
	err := db.WithContext(ctx).
		Table("user_groups").
		Joins("JOIN users_groups ON users_groups.user_group_id = user_groups.id").
		Where("users_groups.user_id = ? AND user_groups.code IS NOT NULL", userID).
		Order("user_groups.id").
		Pluck("user_groups.code", &codes).Error
	if err != nil {
		return nil, err
	}
	return codes, nil
}

// HasGroupCode reports whether the user belongs to a group with code, the
// PHP `$user->groups->pluck('code')->contains($code)` check (for example
// the site-admin group code admin).
func HasGroupCode(ctx context.Context, db *gorm.DB, userID uint, code string) (bool, error) {
	if db == nil {
		return false, fmt.Errorf("golem15.user: gorm handle is missing")
	}
	var n int64
	err := db.WithContext(ctx).
		Table("user_groups").
		Joins("JOIN users_groups ON users_groups.user_group_id = user_groups.id").
		Where("users_groups.user_id = ? AND user_groups.code = ?", userID, code).
		Count(&n).Error
	if err != nil {
		return false, err
	}
	return n > 0, nil
}