#!/usr/bin/env python3

# googletrans comes with a translate(1) command line application but I don't
# like its UI.

import sys;

stdin = sys.stdin;
stdout = sys.stdout;
stderr = sys.stderr;

_exit = exit;
exit = sys.exit;

def printf(s, *args):
	return fprintf(stdout, s, *args);

def fprintf(f, s, *args):
	printing = s if len(args) == 0 else (s % args);
	return f.write(printing);

try:
	import googletrans;
except:
	printf(
		"%s: This Python script requires the \"googletrans\" library.\n",
		sys.argv[0]
	);

def usage(name):
	fprintf(
		stderr, "Usage: %s [source language] [destination language]\n",
		name
	);
	exit(1);

def main(argc, argv):
	accepted_languages = set(list(googletrans.LANGCODES)
		+ list(googletrans.LANGUAGES) + [ "auto" ]);
	good = True;
	isatty = stdout.isatty();
	translator = googletrans.Translator();

	if argc != 3:
		usage(argv[0]);

	src = argv[1].lower();
	dest = argv[2].lower();
	for arg in [ src, dest ]:
		if not(arg in accepted_languages):
			good = False;
			fprintf(stderr,
				"%s: %s: Language not recognized.\n",
				argv[0], arg);
	if(not(good)):
		fprintf(stderr, "The following languages and language codes are"
			+ " recognized:\n");
		print(googletrans.LANGCODES);
		exit(1);

	try:
		text = stdin.read().split('\n')[:-1]
	except KeyboardInterrupt:
		fprintf(stderr, "%s: Cancelled (keyboard interrupt).\n", argv[0]);
		exit(1);
	for line in text:
		try:
			translation = translator.translate(line, src=src, dest=dest);
		except:
			fprintf(stderr, "%s: %s ->%s\n\t%s\n",
				argv[0], line, dest, "Error trying to translate.");
		if isatty:
			fprintf(stdout,
				"%s -> %s\n"
				+ "\t%s -> %s\n"
				+ "\tGiven pronunciation: %s\n",
				translation.origin, translation.text,
				translation.src, translation.dest,
				translation.pronunciation
			);
		else:
			fprintf(stdout, "%s\n", translation.text);
	return 0;

exit(main(len(sys.argv), sys.argv));