feat: notification enhancement

internal/repository/notification_prefs_repo.go

@@ -0,0 +1,99 @@
+package repository
+
+import (
+	"context"
+	"fmt"
+)
+
+// Notification delivery channels (notification_prefs.channel values).
+const (
+	ChannelInApp = "in_app"
+	ChannelEmail = "email"
+	ChannelPush  = "push"
+)
+
+// PrefKey is the lookup key for a (kind, channel) cell in a DisabledSet.
+func PrefKey(kind, channel string) string { return kind + "/" + channel }
+
+// NotificationPrefsRepo stores per-user notification opt-outs: one row per
+// (kind, channel) the user has turned OFF. Absence of a row means enabled,
+// so the table only ever holds overrides and new kinds/channels default on.
+type NotificationPrefsRepo struct{ pg *Postgres }
+
+func NewNotificationPrefsRepo(pg *Postgres) *NotificationPrefsRepo {
+	return &NotificationPrefsRepo{pg: pg}
+}
+
+// DisabledSet returns the user's opt-outs keyed by PrefKey(kind, channel).
+func (r *NotificationPrefsRepo) DisabledSet(ctx context.Context, userID string) (map[string]struct{}, error) {
+	rows, err := r.pg.Pool.Query(ctx, `
+		SELECT kind, channel FROM notification_prefs
+		WHERE user_id = $1 AND enabled = FALSE`, userID)
+	if err != nil {
+		return nil, fmt.Errorf("list notification prefs: %w", err)
+	}
+	defer rows.Close()
+	out := map[string]struct{}{}
+	for rows.Next() {
+		var kind, channel string
+		if err := rows.Scan(&kind, &channel); err != nil {
+			return nil, fmt.Errorf("scan notification pref: %w", err)
+		}
+		out[PrefKey(kind, channel)] = struct{}{}
+	}
+	return out, rows.Err()
+}
+
+// Disable records opt-out rows for every kind × channel pair.
+func (r *NotificationPrefsRepo) Disable(ctx context.Context, userID string, kinds, channels []string) error {
+	_, err := r.pg.Pool.Exec(ctx, `
+		INSERT INTO notification_prefs (user_id, kind, channel, enabled)
+		SELECT $1, k, c, FALSE
+		FROM unnest($2::text[]) AS k, unnest($3::text[]) AS c
+		ON CONFLICT (user_id, kind, channel)
+		    DO UPDATE SET enabled = FALSE, updated_at = now()`,
+		userID, kinds, channels)
+	if err != nil {
+		return fmt.Errorf("disable notification prefs: %w", err)
+	}
+	return nil
+}
+
+// Enable removes opt-out rows (absence = enabled) for every kind × channel
+// pair.
+func (r *NotificationPrefsRepo) Enable(ctx context.Context, userID string, kinds, channels []string) error {
+	_, err := r.pg.Pool.Exec(ctx, `
+		DELETE FROM notification_prefs
+		WHERE user_id = $1 AND kind = ANY($2::text[]) AND channel = ANY($3::text[])`,
+		userID, kinds, channels)
+	if err != nil {
+		return fmt.Errorf("enable notification prefs: %w", err)
+	}
+	return nil
+}
+
+// SyncLegacyColumns recomputes users.like_emails_enabled and
+// users.sadhna_reminders_enabled from the prefs table, so an old frontend
+// (or a rollback) reading the legacy columns stays correct. Call after any
+// prefs write; drop together with the columns once fully rolled out.
+func (r *NotificationPrefsRepo) SyncLegacyColumns(ctx context.Context, userID string) error {
+	_, err := r.pg.Pool.Exec(ctx, `
+		UPDATE users SET
+		    like_emails_enabled = NOT EXISTS (
+		        SELECT 1 FROM notification_prefs np
+		        WHERE np.user_id = users.id
+		          AND np.kind = 'post_like' AND np.channel = 'email'
+		          AND np.enabled = FALSE),
+		    -- The legacy reminder toggle was all-or-nothing: it reads as OFF
+		    -- only when every reminder kind × channel cell is opted out.
+		    sadhna_reminders_enabled = (
+		        SELECT count(*) FROM notification_prefs np
+		        WHERE np.user_id = users.id
+		          AND np.kind IN ('chant_reminder', 'quote_reminder', 'chant_incomplete_reminder')
+		          AND np.enabled = FALSE) < 9
+		WHERE id = $1`, userID)
+	if err != nil {
+		return fmt.Errorf("sync legacy notification prefs: %w", err)
+	}
+	return nil
+}