import { FileStorage } from "@flystorage/file-storage";
import { LocalStorageAdapter } from "@flystorage/local-fs";
import fs from "fs/promises";
import { Log } from "../util/log";
import { App } from "../app/app";
import { AppPath } from "../app/path";
import { Bus } from "../bus";
import z from "zod";

export namespace Storage {
  const log = Log.create({ service: "storage" });

  export const Event = {
    Write: Bus.event(
      "storage.write",
      z.object({ key: z.string(), content: z.any() }),
    ),
  };

  const state = App.state("storage", async () => {
    const app = await App.use();
    const storageDir = AppPath.storage(app.root);
    await fs.mkdir(storageDir, { recursive: true });
    const storage = new FileStorage(new LocalStorageAdapter(storageDir));
    log.info("created", { path: storageDir });
    return {
      storage,
    };
  });

  export async function readJSON<T>(key: string) {
    const storage = await state().then((x) => x.storage);
    const data = await storage.readToString(key + ".json");
    return JSON.parse(data) as T;
  }

  export async function writeJSON<T>(key: string, content: T) {
    const storage = await state().then((x) => x.storage);
    const json = JSON.stringify(content);
    await storage.write(key + ".json", json);
    Bus.publish(Event.Write, { key, content });
  }

  export async function* list(prefix: string) {
    try {
      const storage = await state().then((x) => x.storage);
      const list = storage.list(prefix);
      for await (const item of list) {
        yield item.path.slice(0, -5);
      }
    } catch {
      return;
    }
  }
}