feat(m5): PWA service worker, offline Dexie store, outbox, sync endpoints

internal/store/sync_store.go

@@ -0,0 +1,108 @@
+package store
+
+import (
+	"context"
+	"database/sql"
+	"encoding/json"
+	"fmt"
+
+	"github.com/wotra/wotra/internal/domain"
+)
+
+// SyncStore manages the sync_log and server_version.
+type SyncStore struct {
+	db *sql.DB
+}
+
+func NewSyncStore(db *sql.DB) *SyncStore {
+	return &SyncStore{db: db}
+}
+
+type SyncChange struct {
+	Entity   string `json:"entity"`
+	EntityID string `json:"entity_id"`
+	Op       string `json:"op"` // "upsert" | "delete"
+	Version  int64  `json:"version"`
+	Payload  string `json:"payload"`
+}
+
+// Pull returns all sync_log rows with version > sinceVersion.
+func (s *SyncStore) Pull(ctx context.Context, sinceVersion int64) ([]SyncChange, int64, error) {
+	rows, err := s.db.QueryContext(ctx,
+		`SELECT entity, entity_id, op, version, payload FROM sync_log
+		 WHERE version > ? ORDER BY version ASC`, sinceVersion)
+	if err != nil {
+		return nil, 0, err
+	}
+	defer rows.Close()
+	var changes []SyncChange
+	var maxVersion int64 = sinceVersion
+	for rows.Next() {
+		var c SyncChange
+		if err := rows.Scan(&c.Entity, &c.EntityID, &c.Op, &c.Version, &c.Payload); err != nil {
+			return nil, 0, err
+		}
+		if c.Version > maxVersion {
+			maxVersion = c.Version
+		}
+		changes = append(changes, c)
+	}
+	return changes, maxVersion, rows.Err()
+}
+
+// nextVersion returns the next monotonic version number.
+func (s *SyncStore) nextVersion(ctx context.Context) (int64, error) {
+	var max sql.NullInt64
+	err := s.db.QueryRowContext(ctx, `SELECT MAX(version) FROM sync_log`).Scan(&max)
+	if err != nil {
+		return 0, err
+	}
+	if !max.Valid {
+		return 1, nil
+	}
+	return max.Int64 + 1, nil
+}
+
+// LogEntry appends an entry upsert to the sync log.
+func (s *SyncStore) LogEntry(ctx context.Context, e *domain.Entry) error {
+	payload, err := json.Marshal(e)
+	if err != nil {
+		return err
+	}
+	return s.log(ctx, "entries", e.ID, "upsert", string(payload))
+}
+
+// LogEntryDelete appends an entry delete to the sync log.
+func (s *SyncStore) LogEntryDelete(ctx context.Context, id string) error {
+	payload := fmt.Sprintf(`{"id":%q}`, id)
+	return s.log(ctx, "entries", id, "delete", payload)
+}
+
+// LogClosedDay appends a closed_day upsert to the sync log.
+func (s *SyncStore) LogClosedDay(ctx context.Context, d *domain.ClosedDay) error {
+	payload, err := json.Marshal(d)
+	if err != nil {
+		return err
+	}
+	return s.log(ctx, "closed_days", d.DayKey, "upsert", string(payload))
+}
+
+// LogClosedWeek appends a closed_week upsert to the sync log.
+func (s *SyncStore) LogClosedWeek(ctx context.Context, w *domain.ClosedWeek) error {
+	payload, err := json.Marshal(w)
+	if err != nil {
+		return err
+	}
+	return s.log(ctx, "closed_weeks", w.WeekKey, "upsert", string(payload))
+}
+
+func (s *SyncStore) log(ctx context.Context, entity, entityID, op, payload string) error {
+	version, err := s.nextVersion(ctx)
+	if err != nil {
+		return err
+	}
+	_, err = s.db.ExecContext(ctx,
+		`INSERT INTO sync_log (entity, entity_id, op, version, payload) VALUES (?, ?, ?, ?, ?)`,
+		entity, entityID, op, version, payload)
+	return err
+}