#!/usr/bin/python3

import glob
import http.client
import json
import os
import ssl
import subprocess
import sys
import time
import urllib.request
import yaml


def check_file(filename):
    is_ok = True
    repo_name = None

    def diagnostic(file, level, msg):
        if repo_name is None:
            print('%s: %s: %s' % (level, filename, msg),
                  file=file)
        else:
            print('%s: %s: %s: %s' % (level, filename, repo_name, msg),
                  file=file)

    def error(msg):
        nonlocal is_ok
        is_ok = False
        diagnostic(sys.stderr, 'E', msg)

    def info(msg):
        diagnostic(sys.stdout, 'I', msg)

    def try_command(args, msg_prefix=''):
        result = subprocess.run(
            args,
            stdout=subprocess.DEVNULL, stderr=subprocess.PIPE,
            encoding='utf-8', errors='replace')
        if result.returncode != 0:
            error(msg_prefix + result.stderr.rstrip())
        else:
            info(msg_prefix + 'OK')

    with open(filename) as f:
        try:
            obj = yaml.safe_load(f)
        except yaml.YAMLError:
            f.seek(0)
            obj = json.load(f)

        for repo_name, upstream_def in obj.items():
            upstream_type = upstream_def['type']
            upstream_url = upstream_def.get('url')  # optional for bzr
            check_certificates = upstream_def.get('check-certificates', True)

            # Try the cheapest possible operation to verify that the
            # repository or file is present

            if upstream_type == 'bzr':
                cert_options = []
                if not check_certificates:
                    cert_options.append('-Ossl.cert_reqs=none')
                if upstream_url is None:
                    branch_urls = upstream_def['branches'].items()
                else:
                    branch_urls = [('trunk', upstream_url)]
                for branch_name, branch_url in branch_urls:
                    try_command(['bzr', 'info', '--quiet', *cert_options,
                                 branch_url],
                                msg_prefix=('%s: ' % branch_name))

            elif upstream_type == 'cvs':
                try_command(['cvs', '-d', upstream_url, '-Q', 'rls',
                             upstream_def['module']])

            elif upstream_type == 'git':
                if check_certificates:
                    os.environ.pop('GIT_SSL_NO_VERIFY', None)
                else:
                    os.environ['GIT_SSL_NO_VERIFY'] = 'true'
                try_command(['git', 'ls-remote', '--symref',
                             upstream_url, 'HEAD'])

            elif upstream_type == 'hg':
                # The hg client doesn't appear to support running any
                # kind of info/check command without a local clone.
                # Send a Mercurial capabilities request directly.
                tls_context = ssl.create_default_context()
                if not check_certificates:
                    tls_context.check_hostname = False
                    tls_context.verify_mode = ssl.CERT_NONE
                try:
                    with urllib.request.urlopen(
                            urllib.request.Request(
                                upstream_url + '?cmd=capabilities',
                                headers={
                                    'Accept': 'application/mercurial-0.1',
                                    'User-Agent': 'mercurial/proto-1.0'
                                }),
                            context=tls_context) as result:
                        if result.info().get('Content-Type') \
                           != 'application/mercurial-0.1':
                            error('no Mercurial server support detected')
                        else:
                            info('OK')
                except (urllib.error.URLError, http.client.HTTPException) as e:
                    error(str(e))

            elif upstream_type == 'svn':
                try_command(['svn', 'info', '--non-interactive', upstream_url])

            elif upstream_type in ['gzip', 'tarball', 'zip']:
                try:
                    with urllib.request.urlopen(
                            urllib.request.Request(upstream_url,
                                                   method='HEAD')) as result:
                        if result.info().get('Content-Type') == 'text/html':
                            error('Content-Type is HTML')
                        elif result.info().get('Content-Length') == '0':
                            error('file is empty')
                        else:
                            info('OK')
                except (urllib.error.URLError, http.client.HTTPException) as e:
                    error(str(e))

            # Throttle requests
            time.sleep(0.1)

    return is_ok


def main():
    all_ok = True

    if len(sys.argv) > 1:
        filenames = sys.argv[1:]
    else:
        filenames = sorted(glob.glob('*-lorries/*.lorry'))
    for filename in filenames:
        if not check_file(filename):
            all_ok = False

    sys.exit(0 if all_ok else 1)


if __name__ == '__main__':
    main()