// Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.
import { join } from "../path/mod.ts";

/**
 * Ensures that a directory is empty.
 * Deletes directory contents if the directory is not empty.
 * If the directory does not exist, it is created.
 * The directory itself is not deleted.
 * Requires the `--allow-read` and `--allow-write` flag.
 */
export async function emptyDir(dir: string): Promise<void> {
  try {
    const items = [];
    for await (const dirEntry of Deno.readDir(dir)) {
      items.push(dirEntry);
    }

    while (items.length) {
      const item = items.shift();
      if (item && item.name) {
        const filepath = join(dir, item.name);
        await Deno.remove(filepath, { recursive: true });
      }
    }
  } catch (err) {
    if (!(err instanceof Deno.errors.NotFound)) {
      throw err;
    }

    // if not exist. then create it
    await Deno.mkdir(dir, { recursive: true });
  }
}

/**
 * Ensures that a directory is empty.
 * Deletes directory contents if the directory is not empty.
 * If the directory does not exist, it is created.
 * The directory itself is not deleted.
 * Requires the `--allow-read` and `--allow-write` flag.
 */
export function emptyDirSync(dir: string): void {
  try {
    const items = [...Deno.readDirSync(dir)];

    // If the directory exists, remove all entries inside it.
    while (items.length) {
      const item = items.shift();
      if (item && item.name) {
        const filepath = join(dir, item.name);
        Deno.removeSync(filepath, { recursive: true });
      }
    }
  } catch (err) {
    if (!(err instanceof Deno.errors.NotFound)) {
      throw err;
    }
    // if not exist. then create it
    Deno.mkdirSync(dir, { recursive: true });
    return;
  }
}
