#!/bin/env python3
# vim: set noexpandtab tabstop=4 ft=python :
"""
A script moving pictures from one folder to subfolders (depending on the date they are taken)
"""

import os
import argparse
import re
import shutil
import PIL.Image
import PIL.ExifTags

def get_date(filename):
	"""
	Read EXIF data from a file and return a string containing "yyyymmdd"

	:param filename: The files name
	"""
	image = PIL.Image.open(filename)
	image_exif = image._getexif()
	if not image_exif:
		return None
	matches = re.match(r'(?P<year>\d{4}):(?P<month>\d{2}):(?P<day>\d{2})', image_exif[306])
	image.close()
	if matches is None:
		return None
	return "%04d%02d%02d" % (int(matches["year"]), int(matches["month"]), int(matches["day"]))

def main():
	"""
	Move files to a directory by date

	:param args: CLI arguments
	"""
	# verify we're getting the correct data :)
	if PIL.ExifTags.TAGS[306] != "DateTime":
		print("ERROR: EXIF index for DateTime changed!")
		exit(2)
	# parse arguments
	parser = argparse.ArgumentParser(description="Move/copy pictures to subfolders")
	parser.add_argument("--source", "-s", action="store", default=os.getcwd(), metavar="<path>", \
			help="The source directory (default = current)", dest="source")
	parser.add_argument("--destination", "-d", action="store", default=os.getcwd(), metavar="<path>", \
			help="The destination directory (default = current)", dest="destination")
	parser.add_argument("--copy", "-c", action="store_true", dest="copy_files", \
			help="Copy the files insted of moving them")
	args = parser.parse_args()
	# settings
	source_directory = args.source
	destination_directory = args.destination
	copy_files = args.copy_files
	# iterate through directory
	for filename in os.listdir(source_directory):
		if os.path.isfile(os.path.join(source_directory, filename)) and \
				re.search(r'\.jpg$', filename, flags=re.IGNORECASE):
			date = get_date(os.path.join(source_directory, filename))
			if date is None:
				print("WARNING: No EXIF data for file '%s'" % (filename))
				continue
			directory = os.path.join(destination_directory, date)
			# create directory if it not exists
			if os.path.exists(directory):
				if not os.path.isdir(directory):
					print("'%s' exists but is no directory!" % (date))
					continue
			else:
				print("Creating directory '%s'" % (directory))
				os.mkdir(directory)
			# copy or move file
			if copy_files:
				print("Copy file '%s' to '%s'" % (filename, date))
				shutil.copy2(os.path.join(source_directory, filename), \
						os.path.join(destination_directory, date, filename))
			else:
				print("Moving file '%s' to '%s'" % (filename, date))
				os.rename(os.path.join(source_directory, filename), \
						os.path.join(destination_directory, date, filename))

if __name__ == "__main__":
	main()