#!/usr/bin/python
import os, re


def autosign(*args, **kw):
    u""" 檢查倒數第二版有沒有 GPG 簽章，有則略過
        無則視最新版作者為誰來處理：
            最新版作者為本人(同 hgrc[ui].username)
            則自動簽章。
            非本人則視有沒有 -f 參數來處理
    """
    print('HG Push Start...\n')

    author_name = kw['ui'].username()
    public_key_id = kw['ui'].config('gpg', 'key')
    public_key_url = kw['ui'].config('gpg', 'key_url')
    key_info = os.popen('gpg --list-public-keys %s'
                        %public_key_id).read()
    public_key_uid = re.search(r'uid\s+([^\n]+)',
                        key_info).groups()[0]
    print('Author Name: %s\n'%author_name)
    print('Public Key UID: %s\n'%public_key_uid)

    check_version = os.popen('hg log -r tip^'
                        +'--template "{node|short}"'
                        ).read()
    res = os.popen('hg sigcheck %s'%check_version).read()

    if public_key_uid in res:
        print('No need to sign GPG signature!\n')
        return False
    else:
        print('Head Changeset:\n')
        res0 = os.popen('hg tip -v').read()
        for line in res0.split('\n'): print('\t%s'%line)

        if (not re.search(r'\b'+author_name+r'\b', res0)
            and "push -f" not in kw['args']):
            print('The newest changeset is not yours\n')
            return True
        else:
            version = re.search(
                r'changeset:\s+[0-9]+:([^\s]+)\s',
                                res0).groups()[0]
            key_info = ("with id:%(key_id)s %(key_url)s"
                        % {'key_id': public_key_id,
                        'key_url': public_key_url})
            r = os.popen('hg sign '+version+' -m '
                        '"Added signature('+key_info+')'
                        +' for changeset '+version+'"')

            print('Done for %s\n'%r.read())
            return False


def merge_sigcheck(*args, **kw):
    u""" 若使用者執行 hg merge -r 1234 ，
        則本函式會去驗證 1234^ (1234 的前一版)的簽章。
        若驗證成功，則 return False ，
        不成功則視有沒有傳入 -f 參數
            ($ hg merge -r 1234 -f)
            來 return False or True
    """
    type_version = kw['opts']['rev']
    merge_version = os.popen(('hg log -r %s^'
                        %type_version)
                        +' --template "{node|short}"'
                        ).read()
    res = os.popen('hg sigcheck %s'
                    %merge_version).read()
    if ' signed ' in res:
        return False
    elif ' -f' in kw['args']:
        return False
    else:
        print('changeset:"%s" has no GPG signature!\n'
                %type_version)
        return True