Database-level multi-library support #48 (#58)

* feat: start of library backends

* feat: update backend routes and create initializer

* feat: add legacy library creation

* fix: resolve frontend type errors

* fix: runtime errors

* fix: lint

server/internal/library/provider.ts

@@ -0,0 +1,64 @@
+import type { Readable } from "stream";
+import type { LibraryBackend } from "~/prisma/client";
+
+export abstract class LibraryProvider<CFG> {
+  constructor(_config: CFG, _id: string) {
+    throw new Error("Library doesn't have a proper constructor");
+  }
+
+  /**
+   * @returns ID of the current library provider (fs, smb, s3, etc)
+   */
+  abstract type(): LibraryBackend;
+
+  /**
+   * @returns the specific ID of this current provider
+   */
+  abstract id(): string;
+
+  /**
+   * @returns list of (usually) top-level game folder names
+   */
+  abstract listGames(): Promise<string[]>;
+
+  /**
+   * @param game folder name of the game to list versions for
+   * @returns list of version folder names
+   */
+  abstract listVersions(game: string): Promise<string[]>;
+
+  /**
+   * @param game folder name of the game
+   * @param version folder name of the version
+   * @returns recursive list of all files in version, relative to the version folder (e.g. ./setup.exe)
+   */
+  abstract versionReaddir(game: string, version: string): Promise<string[]>;
+
+  /**
+   * @param game folder name of the game
+   * @param version folder name of the version
+   * @returns string of JSON of the droplet manifest
+   */
+  abstract generateDropletManifest(
+    game: string,
+    version: string,
+    progress: (err: Error | null, v: number) => void,
+    log: (err: Error | null, v: string) => void,
+  ): Promise<string>;
+
+  abstract peekFile(
+    game: string,
+    version: string,
+    filename: string,
+  ): Promise<{ size: number } | undefined>;
+
+  abstract readFile(
+    game: string,
+    version: string,
+    filename: string,
+    options?: { start?: number; end?: number },
+  ): Promise<Readable | undefined>;
+}
+
+export class GameNotFoundError extends Error {}
+export class VersionNotFoundError extends Error {}