import Gio from "gi://Gio";
import GLib from "gi://GLib";
import { readFileAsync } from "astal/file";

export async function readFromStreamRaw(
  stream: Gio.InputStream,
  bytes: number,
): Promise<Uint8Array> {
  return new Promise<Uint8Array>((resolve, reject) => {
    stream.read_bytes_async(
      bytes,
      GLib.PRIORITY_DEFAULT,
      null,
      (stream, result) => {
        try {
          const data = stream!.read_bytes_finish(result);
          const buffer = data.get_data();
          if (buffer === null) {
            reject(new Error("Failed to read from stream"));
            return;
          }
          resolve(buffer);
        } catch (e) {
          reject(e);
        }
      },
    );
  });
}

export async function readFromStream(
  stream: Gio.InputStream,
  bytes: number,
): Promise<Uint8Array> {
  const chunkCount = Math.ceil(bytes / 4096);
  const buffer = await Array.from({ length: chunkCount }, (_, i) => i).reduce(
    async (acc, i) => {
      const buffer = await acc;
      const chunkSize = Math.min(4096, bytes - i * 4096);
      const chunk = await readFromStreamRaw(stream, chunkSize);
      buffer.set(chunk, i * 4096);
      return buffer;
    },
    Promise.resolve(new Uint8Array(bytes)),
  );
  return buffer;
}

export async function writeToStream(
  stream: Gio.OutputStream,
  data: ArrayBuffer | Uint8Array,
): Promise<void> {
  if (data instanceof ArrayBuffer) {
    data = new Uint8Array(data);
  }
  return new Promise<void>((resolve, reject) => {
    stream.write_all_async(
      data as Uint8Array,
      GLib.PRIORITY_DEFAULT,
      null,
      (stream, result) => {
        try {
          stream?.write_all_finish(result) ??
            reject(new Error("Failed to write to stream"));
          resolve();
        } catch (e) {
          reject(e);
        }
      },
    );
  });
}

export async function dereferenceSymbolicLink(
  filename: string,
): Promise<string> {
  return new Promise<string>((resolve, reject) => {
    console.log(`Dereferencing symbolic link for ${filename}`);
    const file = Gio.File.new_for_path(filename);
    file.query_info_async(
      "standard::is-symlink,standard::symlink-target",
      Gio.FileQueryInfoFlags.NOFOLLOW_SYMLINKS,
      GLib.PRIORITY_DEFAULT,
      null,
      (file, result) => {
        try {
          const info = file!.query_info_finish(result);
          if (info.get_is_symlink()) {
            console.log("File is a symlink");
            const target = info.get_symlink_target() as string;
            console.log(target);
            if (target.startsWith("./") || target.startsWith("../")) {
              resolve(file!.resolve_relative_path(target).get_path()!);
            } else if (target.startsWith("/")) {
              resolve(target);
            } else {
              resolve(file!.get_parent()!.get_child(target).get_path()!);
            }
            resolve(file!.resolve_relative_path(target).get_path()!);
          } else {
            resolve(filename);
          }
        } catch (e) {
          console.error(e);
          reject(e);
        }
      },
    );
  });
}

const dbusXml = new Map<string, string>();

export async function getDbusXml(ifaceName: string) {
  if (dbusXml.has(ifaceName)) {
    return dbusXml.get(ifaceName) as string;
  }
  const contents = await readFileAsync(`dbus/${ifaceName}.xml`);
  dbusXml.set(ifaceName, contents);
  return contents;
}

declare global {
  // Add new "rotate" method to Array
  interface Array<T> {
    /**
     * Rotates the array by `n` positions.
     *
     * @param n The number of positions to rotate the array by.
     * @returns The rotated array.
     */
    rotate(n: number): T[];
  }
}

Array.prototype.rotate = function <T>(this: T[], n: number): T[] {
  const array = this;
  const length = array.length;
  if (length === 0) {
    return [];
  }
  n = ((n % length) + length) % length;
  return array.slice(n).concat(array.slice(0, n));
};