#!/usr/bin/python3
# -*- coding: utf-8 -*-

"""Wrapper for syncing CrOS code.

Actions:
  depot_tools    clone depot_tools tree
  int            switch to internal tree
  ext            switch to external tree

Operates on the repo in the cwd.
"""

import argparse
import fnmatch
import os
import subprocess
import sys


REPO_URL = 'https://chromium.googlesource.com/external/repo'
INT_MANIFEST = 'https://chrome-internal.googlesource.com/chromeos/manifest-internal'
EXT_MANIFEST = 'https://chromium.googlesource.com/chromiumos/manifest'


def run(cmd, **kwargs):
    """Run with command tracing."""
    # Python 3.6 doesn't support capture_output.
    if sys.version_info < (3, 7):
        capture_output = kwargs.pop('capture_output', None)
        if capture_output:
            assert 'stdout' not in kwargs and 'stderr' not in kwargs
            kwargs['stdout'] = subprocess.PIPE
            kwargs['stderr'] = subprocess.PIPE

    print(kwargs.get('cwd', os.getcwd()))
    print(' '.join(cmd))
    return subprocess.run(cmd, **kwargs)


def expand_branch(opts):
    """Support branch shortnames."""
    url = INT_MANIFEST if opts.action == 'int' else EXT_MANIFEST
    ret = run(['git', 'ls-remote', url, 'refs/heads/*'], capture_output=True, encoding='utf-8')
    branches = [x.split()[-1].split('/')[-1] for x in ret.stdout.splitlines()]
    ret = []
    for branch in branches:
        if branch.lower() == opts.branch.lower():
            ret = [branch]
            break
        elif fnmatch.fnmatch(branch.lower(), f'*{opts.branch.lower()}*'):
            ret.append(branch)
    if not ret:
        print(f'error: could not match branch {opts.branch}', file=sys.stderr)
        print(f'Available branches:\n{" ".join(sorted(branches))}', file=sys.stderr)
        sys.exit(1)
    if len(ret) > 1:
        print(f'error: too many branches match {opts.branch}:\n{" ".join(sorted(ret))}',
              file=sys.stderr)
        sys.exit(1)
    print(f'Expanded branch {opts.branch} into {ret[0]}')
    return ret[0]


def get_repo_topdir(opts):
    """Find the top dir of this repo client checkout."""
    topdir = os.getcwd()
    while True:
        rdir = os.path.join(topdir, '.repo')
        if os.path.exists(rdir):
            break
        topdir = os.path.dirname(topdir)
        assert topdir != '/'
    return topdir


def set_git_config(opts):
    """Set .git/config settings in all the repos."""
    topdir = get_repo_topdir(opts)
    rdir = os.path.join(topdir, '.repo')

    def gcfg(path, *args):
        cmd = ['git', f'--git-dir={path}', 'config', 'user.email'] + list(args)
        ret = run(cmd, capture_output=True, encoding='utf-8')
        return ret.stdout.strip()

    current_email = gcfg(os.path.join(rdir, 'manifests.git'))
    if current_email == opts.email:
        return

    print(f'Setting e-mail to {opts.email}')
    for root, dirs, files in os.walk(rdir):
        if root.endswith('.git') and not os.path.islink(os.path.join(root, 'config')):
            gcfg(root, opts.email)
            del dirs[:]


def init_repo(opts):
    """Initialize CrOS checkout."""
    cmd = ['repo', 'init', '-c']

    if opts.action == 'int':
        cmd += ['-u', INT_MANIFEST]
        cmd += ['--repo-url', REPO_URL]
    elif opts.action == 'ext':
        cmd += ['-u', EXT_MANIFEST]
        cmd += ['--repo-url', REPO_URL]

    if opts.ref and os.path.realpath(opts.ref) != os.path.realpath(get_repo_topdir(opts)):
        cmd += ['--reference', opts.ref]

    if opts.manifest:
        cmd += ['-m', opts.manifest]

    if opts.group:
        cmd += ['-g', opts.group]

    if opts.branch:
        branch = expand_branch(opts)
        cmd += ['-b', branch]

    ret = run(cmd)
    if ret.returncode:
        return ret.returncode

    set_git_config(opts)

    print('\ncros-repo: all done')
    return 0


def clone_depot_tools():
    """Clone depot_tools repo."""
    ret = run(['git', 'clone', 'https://chromium.googlesource.com/chromium/tools/depot_tools'])
    return ret.returncode


def get_parser():
    """Get command line parser."""
    parser = argparse.ArgumentParser(
        description=__doc__,
        formatter_class=argparse.RawDescriptionHelpFormatter)
    parser.add_argument('-b', '--branch',
                        help='Switch branches (use "main" to get to ToT)')
    parser.add_argument('-r', '--ref', '--reference', default='~/chromiumos/',
                        help='Patch to reference repo (default: %(default)s)')
    parser.add_argument('-g', '--group',
                        help='Manifest group to use (e.g. "minilayout")')
    parser.add_argument('-m', '--manifest',
                        help='Manifest file name to use (e.g. "full.xml")')
    parser.add_argument('-e', '--email', default='vapier@chromium.org',
                        help='E-mail address to force (default: %(default)s)')
    parser.add_argument('action', nargs='?',
                        choices={'depot_tools', 'dt', 'int', 'ext'},
                        help='What to do!')
    return parser


def main(argv):
    """The main func."""
    parser = get_parser()
    opts = parser.parse_args(argv)
    if opts.manifest:
        if '/' in opts.manifest:
           parser.error('manifest should be basename like "full.xml"')
        if opts.manifest.endswith('.xml'):
            opts.manifest = opts.manifest[:-4]
        opts.manifest += '.xml'
    if opts.ref:
        opts.ref = os.path.expanduser(opts.ref)

    if opts.action in {'depot_tools', 'dt'}:
        return clone_depot_tools()
    else:
        return init_repo(opts)


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