""" Remove given suffixes from all files in a directory (ignoring file
extension).

\b
Dependencies:
* click >= 7.0
"""

import os
import sys
import shutil
import ntpath

import click


@click.command(help=__doc__)
@click.argument("suffixes_to_remove", nargs=-1, type=str)
@click.option("--path-dir", type=str, show_default=True, default=".",
              help="Remove suffixes from all files in this directory.")
@click.option("-s", "--existing-file-strategy", type=click.Choice([
    "error", "unique_name", "erase"
]), show_default=True, default="error",
    help="How to handle already existing files before renaming them. Choices "
         "are :\n"
         "* 'error': Raises an error and stop the script.\n"
         "* 'unique_name': Create a guaranted unique name for the new file "
         "by appending a number to it.\n"
         "* 'erase': Erase the already existing file.")
@click.option("--quiet", is_flag=True,
              help="Set this flag if you want to completely silence all "
                   "outputs to stdout.")
def main(suffixes_to_remove, path_dir, existing_file_strategy, quiet):
    if quiet:
        sys.stdout = open(os.devnull, 'w')

    for file_name in os.listdir(path_dir):
        path_file = os.path.join(path_dir, file_name)
        if not os.path.isfile(path_file):
            continue

        file_basename = get_file_basename(file_name)
        for suffix in suffixes_to_remove:
            if file_basename.endswith(suffix):
                file_ext = get_file_extension(file_name)
                print(file_name, file_ext)
                file_ext = "." + file_ext if file_ext != "" else file_ext
                dest_file_name = "{}{}".format(
                    remove_suffix(file_basename, suffix),
                    file_ext
                )
                path_file_dest = os.path.join(path_dir, dest_file_name)
                rename_file(path_file, path_file_dest,
                            strategy=existing_file_strategy)
                break


def rename_file(path_file_src, path_file_dest, strategy):
    if os.path.exists(path_file_dest):
        if strategy == "error":
            raise OSError("Cannot rename \"{}\" into \"{}\", file already "
                          "exists.".format(path_file_src, path_file_dest))
            exit(2)
        elif strategy == "unique_name":
            new_path_file_dest = generate_unique_filename(path_file_dest)
            print("Renaming \"{}\" into \"{}\"".format(path_file_src,
                                                       new_path_file_dest))
            shutil.move(path_file_src, new_path_file_dest)
        elif strategy == "erase":
            print("Renaming \"{}\" into \"{}\" (erasing already existing "
                  "file).".format(path_file_src, path_file_dest))
            shutil.move(path_file_src, path_file_dest)
    else:
        print("Renaming \"{}\" into \"{}\"".format(path_file_src,
                                                   path_file_dest))
        shutil.move(path_file_src, path_file_dest)


def generate_unique_filename(filepath):
    if os.path.isfile(filepath):
        dir_name = ntpath.dirname(filepath)
        dir_name = "." if dir_name == "" else dir_name
        base_name = get_file_basename(filepath)
        ext = get_file_extension(filepath)
        ext = "." + ext if ext != "" else ext

        suffix = 1
        new_filename = "{}_{}{}".format(
            base_name,
            str(suffix),
            ext
        )
        new_filepath = os.path.join(dir_name, new_filename)
        while os.path.isfile(new_filepath):
            suffix += 1
            new_filename = "{}_{}{}".format(
                "_".join(new_filename.split("_")[:-1]),
                str(suffix),
                ext
            )
            new_filepath = os.path.join(dir_name, new_filename)
        return new_filepath
    else:
        return filepath


def remove_suffix(string, suffix):
    if len(suffix) == 0:
        return string
    return string[:-len(suffix)]


def get_file_basename(file_name):
    file_name = ntpath.basename(file_name)
    assert len(file_name) > 0,\
        "Your file name must contains at least one character."

    if file_name[0] != "." and '.' in file_name:
        return ".".join(os.path.basename(file_name).split(".")[:-1])
    elif file_name[0] == "." and '.' in file_name[1:]:
        return ".".join(os.path.basename(file_name).split(".")[:-1])
    else:
        return file_name


def get_file_extension(file_name):
    file_name = ntpath.basename(file_name)
    assert len(file_name) > 0,\
        "Your file name must contains at least one character."

    if file_name[0] != "." and '.' in file_name:
        return file_name.split(".")[-1]
    elif file_name[0] == "." and '.' in file_name[1:]:
        return file_name.split(".")[-1]
    else:
        return ""


if __name__ == '__main__':
    main()