feat: audio track history

internal/repository/audio_progress_repo.go

@@ -0,0 +1,87 @@
+package repository
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/jackc/pgx/v5"
+	"github.com/prabhupadasays/spsays-bff/internal/model"
+)
+
+// AudioProgressRepo wraps Postgres access for audio_progress — the audio
+// player's per-file resume points. One row per (user, audio_key).
+type AudioProgressRepo struct{ pg *Postgres }
+
+func NewAudioProgressRepo(pg *Postgres) *AudioProgressRepo {
+	return &AudioProgressRepo{pg: pg}
+}
+
+// ListByUser returns all of the user's saved resume points, newest first.
+// Used to hydrate the player's in-memory map on sign-in.
+func (r *AudioProgressRepo) ListByUser(ctx context.Context, userID string) ([]model.AudioProgress, error) {
+	rows, err := r.pg.Pool.Query(ctx, `
+		SELECT audio_key, position_seconds, duration_seconds, updated_at
+		FROM audio_progress
+		WHERE user_id = $1
+		ORDER BY updated_at DESC`,
+		userID,
+	)
+	if err != nil {
+		return nil, fmt.Errorf("list audio progress: %w", err)
+	}
+	defer rows.Close()
+
+	var out []model.AudioProgress
+	for rows.Next() {
+		var p model.AudioProgress
+		if err := rows.Scan(&p.Key, &p.Position, &p.Duration, &p.UpdatedAt); err != nil {
+			return nil, fmt.Errorf("scan audio progress: %w", err)
+		}
+		out = append(out, p)
+	}
+	return out, rows.Err()
+}
+
+// Upsert writes a batch of resume points. Each row is inserted or updated
+// only when the incoming updated_at is at least as new as the stored one
+// (newest-wins), so concurrent tabs/devices and the on-login sync of
+// anonymous IndexedDB entries never clobber a fresher position.
+func (r *AudioProgressRepo) Upsert(ctx context.Context, userID string, items []model.AudioProgress) error {
+	if len(items) == 0 {
+		return nil
+	}
+	batch := &pgx.Batch{}
+	for _, it := range items {
+		batch.Queue(`
+			INSERT INTO audio_progress
+			    (user_id, audio_key, position_seconds, duration_seconds, updated_at)
+			VALUES ($1, $2, $3, $4, $5)
+			ON CONFLICT (user_id, audio_key) DO UPDATE
+			    SET position_seconds = EXCLUDED.position_seconds,
+			        duration_seconds = EXCLUDED.duration_seconds,
+			        updated_at       = EXCLUDED.updated_at
+			    WHERE EXCLUDED.updated_at >= audio_progress.updated_at`,
+			userID, it.Key, it.Position, it.Duration, it.UpdatedAt)
+	}
+	br := r.pg.Pool.SendBatch(ctx, batch)
+	defer br.Close()
+	for range items {
+		if _, err := br.Exec(); err != nil {
+			return fmt.Errorf("upsert audio progress: %w", err)
+		}
+	}
+	return nil
+}
+
+// Delete removes a single resume point (called when a track plays to
+// completion so it restarts from the beginning next time).
+func (r *AudioProgressRepo) Delete(ctx context.Context, userID, key string) error {
+	_, err := r.pg.Pool.Exec(ctx,
+		`DELETE FROM audio_progress WHERE user_id = $1 AND audio_key = $2`,
+		userID, key,
+	)
+	if err != nil {
+		return fmt.Errorf("delete audio progress: %w", err)
+	}
+	return nil
+}