Support reading progress synchronization across platforms (#34)

apps/readest-app/src/utils/serializer.ts

@@ -0,0 +1,52 @@
+import { BookConfig, BookSearchConfig, ViewSettings } from '@/types/book';
+
+export const serializeConfig = (
+  config: BookConfig,
+  globalViewSettings: ViewSettings,
+  defaultSearchConfig: BookSearchConfig,
+): string => {
+  config = JSON.parse(JSON.stringify(config));
+  const viewSettings = config.viewSettings as Partial<ViewSettings>;
+  const searchConfig = config.searchConfig as Partial<BookSearchConfig>;
+  config.viewSettings = Object.entries(viewSettings).reduce(
+    (acc: Partial<Record<keyof ViewSettings, unknown>>, [key, value]) => {
+      if (globalViewSettings[key as keyof ViewSettings] !== value) {
+        acc[key as keyof ViewSettings] = value;
+      }
+      return acc;
+    },
+    {} as Partial<Record<keyof ViewSettings, unknown>>,
+  ) as Partial<ViewSettings>;
+  config.searchConfig = Object.entries(searchConfig).reduce(
+    (acc: Partial<Record<keyof BookSearchConfig, unknown>>, [key, value]) => {
+      if (defaultSearchConfig[key as keyof BookSearchConfig] !== value) {
+        acc[key as keyof BookSearchConfig] = value;
+      }
+      return acc;
+    },
+    {} as Partial<BookSearchConfig>,
+  ) as Partial<BookSearchConfig>;
+
+  return JSON.stringify(config);
+};
+
+export const deserializeConfig = (
+  str: string,
+  globalViewSettings: ViewSettings,
+  defaultSearchConfig: BookSearchConfig,
+): BookConfig => {
+  const config = JSON.parse(str) as BookConfig;
+  const { viewSettings, searchConfig } = config;
+  config.viewSettings = { ...globalViewSettings, ...viewSettings };
+  config.searchConfig = { ...defaultSearchConfig, ...searchConfig };
+  config.updatedAt ??= Date.now();
+  return config;
+};
+
+export const compressConfig = (
+  config: BookConfig,
+  globalViewSettings: ViewSettings,
+  defaultSearchConfig: BookSearchConfig,
+): string => {
+  return JSON.parse(serializeConfig(config, globalViewSettings, defaultSearchConfig));
+};