Fix renderer overlay loading and modularize renderer

src/core/services/index.ts

@@ -64,7 +64,11 @@ export {
   updateVisibleOverlayVisibilityService,
 } from "./overlay-visibility-service";
 export { MpvIpcClient, MPV_REQUEST_ID_SECONDARY_SUB_VISIBILITY } from "./mpv-service";
-export { applyMpvSubtitleRenderMetricsPatchService } from "./mpv-render-metrics-service";
+export {
+  applyMpvSubtitleRenderMetricsPatchService,
+  DEFAULT_MPV_SUBTITLE_RENDER_METRICS,
+  sanitizeMpvSubtitleRenderMetrics,
+} from "./mpv-render-metrics-service";
 export { handleMpvCommandFromIpcService } from "./ipc-command-service";
 export { createFieldGroupingOverlayRuntimeService } from "./field-grouping-overlay-service";
 export { createNumericShortcutRuntimeService } from "./numeric-shortcut-service";

src/core/services/mpv-render-metrics-service.test.ts

@@ -1,25 +1,13 @@
 import test from "node:test";
 import assert from "node:assert/strict";
 import { MpvSubtitleRenderMetrics } from "../../types";
-import { applyMpvSubtitleRenderMetricsPatchService } from "./mpv-render-metrics-service";
+import {
+  applyMpvSubtitleRenderMetricsPatchService,
+  DEFAULT_MPV_SUBTITLE_RENDER_METRICS,
+} from "./mpv-render-metrics-service";
 
 const BASE: MpvSubtitleRenderMetrics = {
-  subPos: 100,
-  subFontSize: 38,
-  subScale: 1,
-  subMarginY: 34,
-  subMarginX: 19,
-  subFont: "sans-serif",
-  subSpacing: 0,
-  subBold: false,
-  subItalic: false,
-  subBorderSize: 2.5,
-  subShadowOffset: 0,
-  subAssOverride: "yes",
-  subScaleByWindow: true,
-  subUseMargins: true,
-  osdHeight: 720,
-  osdDimensions: null,
+  ...DEFAULT_MPV_SUBTITLE_RENDER_METRICS,
 };
 
 test("applyMpvSubtitleRenderMetricsPatchService returns unchanged on empty patch", () => {

src/core/services/mpv-render-metrics-service.ts

@@ -1,6 +1,33 @@
 import { MpvSubtitleRenderMetrics } from "../../types";
 import { asBoolean, asFiniteNumber, asString } from "../utils/coerce";
 
+export const DEFAULT_MPV_SUBTITLE_RENDER_METRICS: MpvSubtitleRenderMetrics = {
+  subPos: 100,
+  subFontSize: 38,
+  subScale: 1,
+  subMarginY: 34,
+  subMarginX: 19,
+  subFont: "sans-serif",
+  subSpacing: 0,
+  subBold: false,
+  subItalic: false,
+  subBorderSize: 2.5,
+  subShadowOffset: 0,
+  subAssOverride: "yes",
+  subScaleByWindow: true,
+  subUseMargins: true,
+  osdHeight: 720,
+  osdDimensions: null,
+};
+
+export function sanitizeMpvSubtitleRenderMetrics(
+  current: MpvSubtitleRenderMetrics,
+  patch: Partial<MpvSubtitleRenderMetrics> | null | undefined,
+): MpvSubtitleRenderMetrics {
+  if (!patch) return current;
+  return updateMpvSubtitleRenderMetricsService(current, patch);
+}
+
 export function updateMpvSubtitleRenderMetricsService(
   current: MpvSubtitleRenderMetrics,
   patch: Partial<MpvSubtitleRenderMetrics>,