package store

import (
	"fmt"
	"krafttrainer/internal/model"
)

// ListExerciseImages gibt alle Bilder einer Übung zurück.
func (s *Store) ListExerciseImages(exerciseID int64) ([]model.ExerciseImage, error) {
	rows, err := s.db.Query(`
		SELECT id, exercise_id, filename, sort_order, created_at
		FROM exercise_images
		WHERE exercise_id = ?
		ORDER BY sort_order, id`, exerciseID,
	)
	if err != nil {
		return nil, fmt.Errorf("Bilder abfragen: %w", err)
	}
	defer rows.Close()

	var images []model.ExerciseImage
	for rows.Next() {
		var img model.ExerciseImage
		if err := rows.Scan(&img.ID, &img.ExerciseID, &img.Filename, &img.SortOrder, &img.CreatedAt); err != nil {
			return nil, fmt.Errorf("Bild scannen: %w", err)
		}
		images = append(images, img)
	}
	if images == nil {
		images = []model.ExerciseImage{}
	}
	return images, rows.Err()
}

// CreateExerciseImage speichert einen Bild-Eintrag.
func (s *Store) CreateExerciseImage(exerciseID int64, filename string) (*model.ExerciseImage, error) {
	// sort_order = bisherige Anzahl
	var count int
	s.db.QueryRow(`SELECT COUNT(*) FROM exercise_images WHERE exercise_id = ?`, exerciseID).Scan(&count)

	result, err := s.db.Exec(`
		INSERT INTO exercise_images (exercise_id, filename, sort_order)
		VALUES (?, ?, ?)`, exerciseID, filename, count,
	)
	if err != nil {
		return nil, fmt.Errorf("Bild speichern: %w", err)
	}

	id, _ := result.LastInsertId()
	var img model.ExerciseImage
	err = s.db.QueryRow(`
		SELECT id, exercise_id, filename, sort_order, created_at
		FROM exercise_images WHERE id = ?`, id,
	).Scan(&img.ID, &img.ExerciseID, &img.Filename, &img.SortOrder, &img.CreatedAt)
	if err != nil {
		return nil, fmt.Errorf("Bild abfragen: %w", err)
	}
	return &img, nil
}

// DeleteExerciseImage löscht ein Bild und gibt den Dateinamen zurück.
func (s *Store) DeleteExerciseImage(imageID int64) (string, error) {
	var filename string
	err := s.db.QueryRow(`SELECT filename FROM exercise_images WHERE id = ?`, imageID).Scan(&filename)
	if err != nil {
		return "", fmt.Errorf("Bild nicht gefunden: %w", err)
	}

	_, err = s.db.Exec(`DELETE FROM exercise_images WHERE id = ?`, imageID)
	if err != nil {
		return "", fmt.Errorf("Bild löschen: %w", err)
	}
	return filename, nil
}