Add vendor dict fallback logic

src/main/frequency-dictionary-runtime.ts

@@ -0,0 +1,80 @@
+import * as path from "path";
+import type { FrequencyDictionaryLookup } from "../types";
+import { createFrequencyDictionaryLookupService } from "../core/services";
+
+export interface FrequencyDictionarySearchPathDeps {
+  getDictionaryRoots: () => string[];
+  getSourcePath?: () => string | undefined;
+}
+
+export interface FrequencyDictionaryRuntimeDeps {
+  isFrequencyDictionaryEnabled: () => boolean;
+  getSearchPaths: () => string[];
+  setFrequencyRankLookup: (lookup: FrequencyDictionaryLookup) => void;
+  log: (message: string) => void;
+}
+
+let frequencyDictionaryLookupInitialized = false;
+let frequencyDictionaryLookupInitialization: Promise<void> | null = null;
+
+export function getFrequencyDictionarySearchPaths(
+  deps: FrequencyDictionarySearchPathDeps,
+): string[] {
+  const dictionaryRoots = deps.getDictionaryRoots();
+  const sourcePath = deps.getSourcePath?.();
+
+  const rawSearchPaths: string[] = [];
+  if (sourcePath && sourcePath.trim()) {
+    rawSearchPaths.push(sourcePath.trim());
+    rawSearchPaths.push(path.join(sourcePath.trim(), "frequency-dictionary"));
+    rawSearchPaths.push(path.join(sourcePath.trim(), "vendor", "frequency-dictionary"));
+  }
+
+  for (const dictionaryRoot of dictionaryRoots) {
+    rawSearchPaths.push(dictionaryRoot);
+    rawSearchPaths.push(path.join(dictionaryRoot, "frequency-dictionary"));
+    rawSearchPaths.push(path.join(dictionaryRoot, "vendor", "frequency-dictionary"));
+  }
+
+  return [...new Set(rawSearchPaths)];
+}
+
+export async function initializeFrequencyDictionaryLookup(
+  deps: FrequencyDictionaryRuntimeDeps,
+): Promise<void> {
+  const lookup = await createFrequencyDictionaryLookupService({
+    searchPaths: deps.getSearchPaths(),
+    log: deps.log,
+  });
+  deps.setFrequencyRankLookup(lookup);
+}
+
+export async function ensureFrequencyDictionaryLookup(
+  deps: FrequencyDictionaryRuntimeDeps,
+): Promise<void> {
+  if (!deps.isFrequencyDictionaryEnabled()) {
+    return;
+  }
+  if (frequencyDictionaryLookupInitialized) {
+    return;
+  }
+  if (!frequencyDictionaryLookupInitialization) {
+    frequencyDictionaryLookupInitialization = initializeFrequencyDictionaryLookup(deps)
+      .then(() => {
+        frequencyDictionaryLookupInitialized = true;
+      })
+      .catch((error) => {
+        frequencyDictionaryLookupInitialization = null;
+        throw error;
+      });
+  }
+  await frequencyDictionaryLookupInitialization;
+}
+
+export function createFrequencyDictionaryRuntimeService(
+  deps: FrequencyDictionaryRuntimeDeps,
+): { ensureFrequencyDictionaryLookup: () => Promise<void> } {
+  return {
+    ensureFrequencyDictionaryLookup: () => ensureFrequencyDictionaryLookup(deps),
+  };
+}

src/main/state.ts

@@ -7,6 +7,7 @@ import type {
   SubtitlePosition,
   KikuFieldGroupingChoice,
   JlptLevel,
+  FrequencyDictionaryLookup,
 } from "../types";
 import type { CliArgs } from "../cli/args";
 import type { SubtitleTimingTracker } from "../subtitle-timing-tracker";
@@ -55,6 +56,7 @@ export interface AppState {
   autoStartOverlay: boolean;
   texthookerOnlyMode: boolean;
   jlptLevelLookup: (term: string) => JlptLevel | null;
+  frequencyRankLookup: FrequencyDictionaryLookup;
 }
 
 export interface AppStateInitialValues {
@@ -115,6 +117,7 @@ export function createAppState(values: AppStateInitialValues): AppState {
     autoStartOverlay: values.autoStartOverlay ?? false,
     texthookerOnlyMode: values.texthookerOnlyMode ?? false,
     jlptLevelLookup: () => null,
+    frequencyRankLookup: () => null,
   };
 }