Add database schema, ERD, and repository layer

internal/database/download_repository.go

@@ -0,0 +1,122 @@
+package database
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	"github.com/jackc/pgx/v5/pgxpool"
+)
+
+type Download struct {
+	ID           string
+	TorrentID    string
+	AlbumID      string
+	Format       string
+	Quality      string
+	State        string
+	QbitHash     string
+	SavePath     string
+	ErrorMessage string
+	QueuedAt     time.Time
+	StartedAt    *time.Time
+	CompletedAt  *time.Time
+	CreatedAt    time.Time
+	UpdatedAt    time.Time
+}
+
+type DownloadRepository struct {
+	pool *pgxpool.Pool
+}
+
+func NewDownloadRepository(pool *pgxpool.Pool) *DownloadRepository {
+	return &DownloadRepository{pool: pool}
+}
+
+func (r *DownloadRepository) Create(ctx context.Context, d *Download) error {
+	err := r.pool.QueryRow(ctx,
+		`INSERT INTO downloads (torrent_id, album_id, format, quality, state, qbit_hash, save_path)
+		 VALUES ($1, $2, $3, $4, $5, $6, $7)
+		 RETURNING id, queued_at, created_at, updated_at`,
+		d.TorrentID, d.AlbumID, d.Format, d.Quality, d.State, d.QbitHash, d.SavePath,
+	).Scan(&d.ID, &d.QueuedAt, &d.CreatedAt, &d.UpdatedAt)
+	if err != nil {
+		return fmt.Errorf("creating download: %w", err)
+	}
+	return nil
+}
+
+func (r *DownloadRepository) UpdateState(ctx context.Context, id string, state string) error {
+	_, err := r.pool.Exec(ctx,
+		`UPDATE downloads SET state = $1, updated_at = NOW() WHERE id = $2`, state, id,
+	)
+	if err != nil {
+		return fmt.Errorf("updating download state: %w", err)
+	}
+	return nil
+}
+
+func (r *DownloadRepository) SetStarted(ctx context.Context, id string) error {
+	_, err := r.pool.Exec(ctx,
+		`UPDATE downloads SET state = 'downloading', started_at = NOW(), updated_at = NOW() WHERE id = $1`, id,
+	)
+	if err != nil {
+		return fmt.Errorf("setting download started: %w", err)
+	}
+	return nil
+}
+
+func (r *DownloadRepository) SetCompleted(ctx context.Context, id string, savePath string) error {
+	_, err := r.pool.Exec(ctx,
+		`UPDATE downloads SET state = 'completed', save_path = $1, completed_at = NOW(), updated_at = NOW() WHERE id = $2`, savePath, id,
+	)
+	if err != nil {
+		return fmt.Errorf("setting download completed: %w", err)
+	}
+	return nil
+}
+
+func (r *DownloadRepository) SetFailed(ctx context.Context, id string, errorMsg string) error {
+	_, err := r.pool.Exec(ctx,
+		`UPDATE downloads SET state = 'failed', error_message = $1, updated_at = NOW() WHERE id = $2`, errorMsg, id,
+	)
+	if err != nil {
+		return fmt.Errorf("setting download failed: %w", err)
+	}
+	return nil
+}
+
+func (r *DownloadRepository) GetByAlbumID(ctx context.Context, albumID string) ([]*Download, error) {
+	rows, err := r.pool.Query(ctx,
+		`SELECT id, torrent_id, album_id, format, quality, state, qbit_hash, save_path, error_message, queued_at, started_at, completed_at, created_at, updated_at
+		 FROM downloads WHERE album_id = $1 ORDER BY created_at DESC`, albumID,
+	)
+	if err != nil {
+		return nil, fmt.Errorf("listing downloads: %w", err)
+	}
+	defer rows.Close()
+
+	var downloads []*Download
+	for rows.Next() {
+		d := &Download{}
+		if err := rows.Scan(&d.ID, &d.TorrentID, &d.AlbumID, &d.Format, &d.Quality, &d.State, &d.QbitHash, &d.SavePath, &d.ErrorMessage, &d.QueuedAt, &d.StartedAt, &d.CompletedAt, &d.CreatedAt, &d.UpdatedAt); err != nil {
+			return nil, fmt.Errorf("scanning download: %w", err)
+		}
+		downloads = append(downloads, d)
+	}
+	return downloads, nil
+}
+
+func (r *DownloadRepository) HasAlbumInQuality(ctx context.Context, albumID string, format string, quality string) (bool, error) {
+	var exists bool
+	err := r.pool.QueryRow(ctx,
+		`SELECT EXISTS(
+			SELECT 1 FROM downloads
+			WHERE album_id = $1 AND format = $2 AND quality = $3 AND state IN ('completed', 'seeding')
+		)`, albumID, format, quality,
+	).Scan(&exists)
+	if err != nil {
+		return false, fmt.Errorf("checking album quality: %w", err)
+	}
+	return exists, nil
+}