import argparse
import os
import shutil
import concurrent.futures
import random


version = "1.0.0"


def is_in_whitelist(file_name, whitelist):
    # 获取文件的后缀名
    _, ext = os.path.splitext(file_name)
    # 判断后缀名是否在白名单中
    return ext.lower() in whitelist


def list_files(directory, whitelist, blacklist):
    # 遍历目录中的文件和文件夹
    res = []
    for root, dirs, files in os.walk(directory):
        # 只输出文件名，不包括文件夹
        for file in files:
            if not file.startswith(".") and is_in_whitelist(file, whitelist):
                file_path = os.path.join(root, file)
                res.append(file_path)

    return res


def check_path(path_to_check):
    try:
        if not os.path.exists(path_to_check):
            os.makedirs(path_to_check)
    except OSError as e:
        print(f"发生错误: {e}")


def copy_file(src_file, dst_file):
    if os.path.exists(dst_file):
        print(f"文件 {dst_file} 已存在")
    else:
        try:
            shutil.copy(src_file, dst_file)
            print(f"文件已成功从 {src_file} 拷贝到 {dst_file}")
        except FileNotFoundError:
            print(f"源文件 {src_file} 不存在")
        except PermissionError:
            print(f"没有权限拷贝文件到 {dst_file}")
        except Exception as e:
            print(f"发生错误: {e}")


def copy_files_concurrently(src_files, dst_dir):
    with concurrent.futures.ThreadPoolExecutor() as executor:
        futures = [executor.submit(copy_file, src, os.path.join(dst_dir, os.path.basename(src))) for src in src_files]
        for future in concurrent.futures.as_completed(futures):
            try:
                # 你可以在这里处理返回的结果（如果有的话），但在这个例子中，copy_file没有返回值
                pass
            except Exception as exc:
                print(f'Generated an exception: {exc}')


def main():
    parse = argparse.ArgumentParser("可以随机抓取指定目录下的文件，可指定后缀名，指定要抓取的数量\n")
    parse.add_argument("-v", "--version", action="version", version=version)
    parse.add_argument("input", help="输入路径")
    parse.add_argument("output", help="输出路径")
    parse.add_argument("--count", type=int, help="随机抓取的文件数量,不设置则抓取所有文件")
    parse.add_argument("--whitelist", nargs='+', help="文件后缀名白名单，如果设置白名单，则只会选取白名单中的文件格式")
    parse.add_argument("--blacklist", nargs='+', help="[未实装]文件后缀名黑名单，如果设置黑名单，则会选取过滤黑名单中的文件格式")

    args = parse.parse_args()

    whitelist = []
    blacklist = []
    count = -1

    if args.whitelist:
        for suffix in args.whitelist:
            if not suffix.startswith("."):
                whitelist.append("." + suffix)
            else:
                whitelist.append(suffix)

    if args.blacklist:
        for suffix in args.blacklist:
            if not suffix.startswith("."):
                blacklist.append("." + suffix)
            else:
                blacklist.append(suffix)

    if args.count:
        count = args.count

    files = list_files(args.input, whitelist, blacklist)
    files_to_copy = []

    check_path(args.output)

    if count == -1 or len(files) <= count:
        # 拷贝全部
        files_to_copy = files
    else:
        files_to_copy = random.sample(files, count)

    copy_files_concurrently(files_to_copy, args.output)


if __name__ == "__main__":
    main()