#!/usr/bin/env python
# encoding: UTF-8

# SPDX-FileCopyrightText: Chris Pressey, the original author of this work, has dedicated it to the public domain.
# For more information, please refer to <https://unlicense.org/>
# SPDX-License-Identifier: Unlicense

"""stars2links {options} username

Convert a user's list of starred repositories on Github to a Markdown
document containing links to all the repositories, with their descriptions
and homepages.

Useful if you've been a little too star-happy lately.  Starring is a great
quick way to bookmark Github projects, but it can get out of hand; sometimes
you just want to remember that a project exists.

Requires `requests`.

Example:

  pip install --user requests
  stars2links --login=yourgithublogin catseye --output=stars.md
  pandoc --from=markdown --to=html5 --standalone <stars.md >stars.html
  firefox stars.html

"""

import codecs
import getpass
import optparse
import re
import sys

import requests


def each_api_thing(username, url_template, auth=None,
                   api_prefix='https://api.github.com'):
    url = (api_prefix + url_template) % username

    done = False
    while not done:
        response = requests.get(url, auth=auth)
        data = response.json()
        if 'message' in data:
            raise ValueError(data)
        for item in data:
            yield item
        link = response.headers.get('Link', None)
        if link is None:
            done = True
        else:
            match = re.match(r'^.*\<(.*?)\>\s*\;\s*rel\s*=\s*\"next\"', link)
            if not match:
                done = True
            else:
                url = match.group(1)
                assert '>' not in url, (link, url)


def each_user_star(username, auth=None):
    for item in each_api_thing(username, '/users/%s/starred', auth=auth):
        yield item


def main(args):
    parser = optparse.OptionParser(__doc__)
    parser.add_option("--login",
                      default=None, metavar='USERNAME',
                      help="username to login with when using the "
                           "Github API")
    parser.add_option("--output",
                      default=None, metavar='FILENAME',
                      help="redirect output to a file (UTF-8 sound)")
    parser.add_option("--generate-clone-script", action='store_true',
                      help="generate commands to git clone the repos")
    (options, args) = parser.parse_args(args)
    try:
        username = args[0]
    except IndexError:
        print "Usage: stars2links {options} username"
        print "Run 'stars2links --help' for full usage."
        sys.exit(1)

    auth = None
    if options.login is not None:
        password = getpass.getpass('Password: ')
        auth = (options.login, password)

    stars = {}
    for star in each_user_star(username, auth=auth):
        stars[star['full_name']] = star

    output_file = sys.stdout
    if options.output:
        output_file = codecs.open(options.output, 'w', 'utf-8')

    for star_key in sorted(stars):
        star = stars[star_key]
        if options.generate_clone_script:
            output_file.write("git clone {} {}\n".format(star['html_url'], star['full_name'].replace('/', '__')))
            continue
        output_file.write(u"""
### [%s](%s)

%s""" % (star['full_name'], star['html_url'], star['description']))
        if star['homepage']:
            homepage = star['homepage']
            if not homepage.startswith(('http://', 'https://')):
                homepage = 'http://' + homepage
            output_file.write(u" — [%s](%s)" % (
                star['homepage'], star['homepage'])
            )
        output_file.write(u"\n")


if __name__ == '__main__':
    main(sys.argv[1:])