#!/usr/bin/env python3.5
# coding=utf-8


"""
merge_images

Usage:  For usage instructions run with option --help
Author: Stephan Porada <sporada@uni-bielefeld.de>

"""

import argparse
import os
import subprocess


def parse_arguments():
    parser = argparse.ArgumentParser(description='Merges given input images '
                                                 'into one multipage tiff.')
    parser.add_argument('-i', dest='input_dir', required=True,
                        type=os.path.abspath)
    parser.add_argument('-o', dest='output_dir', required=True,
                        type=os.path.abspath)
    return parser.parse_args()


def merge_images(input_dir, output_dir):
    try:
        os.mkdir(output_dir)
    except FileExistsError:
        pass
    cmd = 'ls -Q -v {i}/*.* > {i}/file_list.txt'.format(i=input_dir)
    subprocess.run(cmd, shell=True)
    cmd = 'convert @{i}/file_list.txt {o}/combined.tif'.format(i=input_dir,
                                                               o=output_dir)
    subprocess.run(cmd, shell=True)
    cmd = 'rm {i}/file_list.txt'.format(i=input_dir)
    subprocess.run(cmd)


def main():
    args = parse_arguments()
    merge_images(args.input_dir, args.output_dir)


if __name__ == '__main__':
    main()