#!/usr/bin/env python3
import argparse
import io
import json
import os.path
import plistlib
import re
import urllib.request
from typing import Any

import cson  # pip install cson

TOKEN = re.compile(br'(\\\\|\\"|"|//|\n)')


def json_with_comments(s: bytes) -> Any:
    bio = io.BytesIO()

    idx = 0
    in_string = False
    in_comment = False

    match = TOKEN.search(s, idx)
    while match:
        if not in_comment:
            bio.write(s[idx:match.start()])

        tok = match[0]
        if not in_comment and tok == b'"':
            in_string = not in_string
        elif in_comment and tok == b'\n':
            in_comment = False
        elif not in_string and tok == b'//':
            in_comment = True

        if not in_comment:
            bio.write(tok)

        idx = match.end()
        match = TOKEN.search(s, idx)

    bio.seek(0)
    return json.load(bio)


STRATEGIES = (json.loads, plistlib.loads, cson.loads, json_with_comments)


def main() -> int:
    parser = argparse.ArgumentParser()
    parser.add_argument('name')
    parser.add_argument('url')
    args = parser.parse_args()

    if '/blob/' in args.url:
        url = args.url.replace('/blob/', '/raw/')
    else:
        url = args.url

    contents = urllib.request.urlopen(url).read()

    errors = []
    for strategy in STRATEGIES:
        try:
            loaded = strategy(contents)
        except Exception as e:
            errors.append((f'{strategy.__module__}.{strategy.__name__}', e))
        else:
            break
    else:
        errors_s = '\n'.join(f'\t{name}: {error}' for name, error in errors)
        raise AssertionError(f'could not load as json/plist/cson:\n{errors_s}')

    config_dir = os.path.expanduser('~/.config/babi')
    os.makedirs(config_dir, exist_ok=True)
    dest = os.path.join(config_dir, f'{args.name}.json')
    with open(dest, 'w') as f:
        json.dump(loaded, f)

    theme_json = os.path.join(config_dir, 'theme.json')
    if os.path.lexists(theme_json):
        os.remove(theme_json)
    os.symlink(dest, theme_json)
    return 0


if __name__ == '__main__':
    exit(main())