import type { WritableDirectoryHandle } from "./mp3Tags";

const DB_NAME = "aurora-spotirip";
const STORE_NAME = "handles";
const OUTPUT_KEY = "output-directory";

type PermissionedDirectoryHandle = WritableDirectoryHandle & {
  queryPermission?: (options?: { mode?: "read" | "readwrite" }) => Promise<"granted" | "denied" | "prompt">;
  requestPermission?: (options?: { mode?: "read" | "readwrite" }) => Promise<"granted" | "denied" | "prompt">;
};

function openDb() {
  return new Promise<IDBDatabase>((resolve, reject) => {
    const request = indexedDB.open(DB_NAME, 1);
    request.onupgradeneeded = () => {
      if (!request.result.objectStoreNames.contains(STORE_NAME)) {
        request.result.createObjectStore(STORE_NAME);
      }
    };
    request.onsuccess = () => resolve(request.result);
    request.onerror = () => reject(request.error || new Error("Unable to open local folder settings."));
  });
}

export async function saveOutputDirectory(handle: WritableDirectoryHandle) {
  const db = await openDb();
  try {
    await new Promise<void>((resolve, reject) => {
      const tx = db.transaction(STORE_NAME, "readwrite");
      tx.objectStore(STORE_NAME).put(handle, OUTPUT_KEY);
      tx.oncomplete = () => resolve();
      tx.onerror = () => reject(tx.error || new Error("Unable to save output folder."));
    });
  } finally {
    db.close();
  }
}

export async function loadOutputDirectory(): Promise<WritableDirectoryHandle | undefined> {
  if (typeof indexedDB === "undefined") return undefined;
  const db = await openDb();
  try {
    return await new Promise<WritableDirectoryHandle | undefined>((resolve, reject) => {
      const tx = db.transaction(STORE_NAME, "readonly");
      const request = tx.objectStore(STORE_NAME).get(OUTPUT_KEY);
      request.onsuccess = () => resolve(request.result as WritableDirectoryHandle | undefined);
      request.onerror = () => reject(request.error || new Error("Unable to restore output folder."));
    });
  } finally {
    db.close();
  }
}

export async function ensureDirectoryWritePermission(handle: WritableDirectoryHandle) {
  const permissioned = handle as PermissionedDirectoryHandle;
  if (!permissioned.queryPermission || !permissioned.requestPermission) return true;
  const current = await permissioned.queryPermission({ mode: "readwrite" });
  if (current === "granted") return true;
  return (await permissioned.requestPermission({ mode: "readwrite" })) === "granted";
}