refactor: deduplicate runtime validation into shared module

static/player/mode.ts

@@ -5,42 +5,7 @@ import { updateQualityOptions } from "./quality";
 import { safeLocalStorage } from "./storage";
 import { streamUrlForMode } from "./source";
 import { loadVideoSource } from "./video";
-import type { ModeSource } from "./types";
+import { isRecord, parseModeSources } from "./validate";
-
-const isRecord = (v: unknown): v is Record<string, unknown> =>
-  typeof v === "object" && v !== null && !Array.isArray(v);
-
-const isStringArray = (v: unknown): v is string[] =>
-  Array.isArray(v) && v.every((item) => typeof item === "string");
-
-const isSubtitleItemArray = (v: unknown): v is { lang: string; token: string }[] =>
-  Array.isArray(v) &&
-  v.every(
-    (item) => isRecord(item) && typeof item.lang === "string" && typeof item.token === "string",
-  );
-
-const parseModeSources = (v: unknown): Record<string, ModeSource> => {
-  if (!isRecord(v)) return {};
-
-  const out: Record<string, ModeSource> = {};
-  for (const [key, value] of Object.entries(v)) {
-    if (!isRecord(value)) continue;
-    if (typeof value.token !== "string" || value.token === "") continue;
-
-    const subtitles = value.subtitles == null ? [] : value.subtitles;
-    if (!isSubtitleItemArray(subtitles)) continue;
-
-    const qualities = value.qualities;
-    out[key] = {
-      token: value.token,
-      type: typeof value.type === "string" ? value.type : undefined,
-      subtitles,
-      qualities: isStringArray(qualities) ? qualities : undefined,
-    };
-  }
-
-  return out;
-};
 
 const alternateModeFor = (mode: string): "sub" | "dub" | null => {
   if (mode === "sub") return "dub";

static/player/state.ts

@@ -1,4 +1,5 @@
 import type { ModeSource, SkipSegment, SubtitleCue, SubtitleTrack, ActiveSegment } from "./types";
+import { parseModeSources, parseSegments } from "./validate";
 import { q, qs, dataset } from "../q";
 import { safeLocalStorage } from "./storage";
 
@@ -180,54 +181,6 @@ export const initState = (c: HTMLElement): boolean => {
     }
   };
 
-  const isRecord = (v: unknown): v is Record<string, unknown> =>
-    typeof v === "object" && v !== null && !Array.isArray(v);
-
-  const isStringArray = (v: unknown): v is string[] =>
-    Array.isArray(v) && v.every((item) => typeof item === "string");
-
-  const isSubtitleItemArray = (v: unknown): v is { lang: string; token: string }[] =>
-    Array.isArray(v) &&
-    v.every(
-      (item) => isRecord(item) && typeof item.lang === "string" && typeof item.token === "string",
-    );
-
-  const parseModeSources = (v: unknown): Record<string, ModeSource> => {
-    if (!isRecord(v)) return {};
-    const out: Record<string, ModeSource> = {};
-    for (const [key, value] of Object.entries(v)) {
-      if (!isRecord(value)) continue;
-      if (typeof value.token !== "string" || value.token === "") continue;
-      // `subtitles` can be `null` when the backend has no subtitles for the stream.
-      // Treat that as an empty list instead of dropping the whole mode source.
-      const subtitles = value.subtitles == null ? [] : value.subtitles;
-      if (!isSubtitleItemArray(subtitles)) continue;
-      const qualities = value.qualities;
-      out[key] = {
-        token: value.token,
-        type: typeof value.type === "string" ? value.type : undefined,
-        subtitles,
-        qualities: isStringArray(qualities) ? qualities : undefined,
-      };
-    }
-    return out;
-  };
-
-  const parseSegments = (v: unknown): SkipSegment[] => {
-    if (!Array.isArray(v)) return [];
-    const out: SkipSegment[] = [];
-    for (const item of v) {
-      if (!isRecord(item)) continue;
-      const type = typeof item.type === "string" ? item.type : "";
-      const start = typeof item.start === "number" ? item.start : Number(item.start);
-      const end = typeof item.end === "number" ? item.end : Number(item.end);
-      const source = typeof item.source === "string" ? item.source : undefined;
-      if (!type || !Number.isFinite(start) || !Number.isFinite(end)) continue;
-      out.push({ type, start, end, source });
-    }
-    return out;
-  };
-
   // mode sources = { sub: { token, subtitles, qualities }, dub: { ... } }
   state.modeSources = parseModeSources(safeJsonUnknown(dataset(c, "modeSources")));
 

static/player/validate.ts

@@ -0,0 +1,47 @@
+import type { ModeSource, SkipSegment } from "./types";
+
+export const isRecord = (v: unknown): v is Record<string, unknown> =>
+  typeof v === "object" && v !== null && !Array.isArray(v);
+
+export const isStringArray = (v: unknown): v is string[] =>
+  Array.isArray(v) && v.every((item) => typeof item === "string");
+
+export const isSubtitleItemArray = (v: unknown): v is { lang: string; token: string }[] =>
+  Array.isArray(v) &&
+  v.every(
+    (item) => isRecord(item) && typeof item.lang === "string" && typeof item.token === "string",
+  );
+
+export const parseModeSources = (v: unknown): Record<string, ModeSource> => {
+  if (!isRecord(v)) return {};
+  const out: Record<string, ModeSource> = {};
+  for (const [key, value] of Object.entries(v)) {
+    if (!isRecord(value)) continue;
+    if (typeof value.token !== "string" || value.token === "") continue;
+    const subtitles = value.subtitles == null ? [] : value.subtitles;
+    if (!isSubtitleItemArray(subtitles)) continue;
+    const qualities = value.qualities;
+    out[key] = {
+      token: value.token,
+      type: typeof value.type === "string" ? value.type : undefined,
+      subtitles,
+      qualities: isStringArray(qualities) ? qualities : undefined,
+    };
+  }
+  return out;
+};
+
+export const parseSegments = (v: unknown): SkipSegment[] => {
+  if (!Array.isArray(v)) return [];
+  const out: SkipSegment[] = [];
+  for (const item of v) {
+    if (!isRecord(item)) continue;
+    const type = typeof item.type === "string" ? item.type : "";
+    const start = typeof item.start === "number" ? item.start : Number(item.start);
+    const end = typeof item.end === "number" ? item.end : Number(item.end);
+    const source = typeof item.source === "string" ? item.source : undefined;
+    if (!type || !Number.isFinite(start) || !Number.isFinite(end)) continue;
+    out.push({ type, start, end, source });
+  }
+  return out;
+};