# Copyright (C) 2009 Canonical
#
# Authors:
#  Michael Vogt
#
# This program is free software; you can redistribute it and/or modify it under
# the terms of the GNU General Public License as published by the Free Software
# Foundation; version 3.
#
# This program is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
# FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
# details.
#
# You should have received a copy of the GNU General Public License along with
# this program; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

import apt
import apt_pkg
import logging
import re
import time
import xml.sax.saxutils

# define additional entities for the unescape method, needed
# because only '&', '<', and '>' are included by default
ESCAPE_ENTITIES = {"'":"'",
                   '"':'"'}

class ExecutionTime(object):
    """
    Helper that can be used in with statements to have a simple
    measure of the timming of a particular block of code, e.g.
    with ExecutinTime("db flush"):
        db.flush()
    """
    def __init__(self, info=""):
        self.info = info
    def __enter__(self):
        self.now = time.time()
    def __exit__(self, type, value, stack):
        print "%s: %s" % (self.info, time.time() - self.now)

def htmlize_package_desc(desc):
    def _is_bullet(line):
        return re.match("^(\s*[-*])", line)
    inside_p = False
    inside_li = False
    indent_len = None
    for line in desc.splitlines():
        stripped_line = line.strip()
        if (not inside_p and 
            not inside_li and 
            not _is_bullet(line) and
            stripped_line):
            yield '<p tabindex="0">'
            inside_p = True
        if stripped_line:
            match = re.match("^(\s*[-*])", line)
            if match:
                if inside_li:
                    yield "</li>"
                yield "<li>"
                inside_li = True
                indent_len = len(match.group(1))
                stripped_line = line[indent_len:].strip()
                yield stripped_line
            elif inside_li:
                if not line.startswith(" " * indent_len):
                    yield "</li>"
                    inside_li = False
                yield stripped_line
            else:
                yield stripped_line
        else:
            if inside_li:
                yield "</li>"
                inside_li = False
            if inside_p:
                yield "</p>"
                inside_p = False
    if inside_li:
        yield "</li>"
    if inside_p:
        yield "</p>"

def get_http_proxy_string_from_gconf():
    """Helper that gets the http proxy from gconf

    Returns: string with http://auth:pw@proxy:port/ or None
    """
    try:
        import gconf, glib
        client = gconf.client_get_default()
        if client.get_bool("/system/http_proxy/use_http_proxy"):
            authentication = ""
            if client.get_bool("/system/http_proxy/use_authentication"):
                user = client.get_string("/system/http_proxy/authentication_user")
                password = client.get_string("/system/http_proxy/authentication_password")
                authentication = "%s:%s@" % (user, password)
            host = client.get_string("/system/http_proxy/host")
            port = client.get_int("/system/http_proxy/port")
            http_proxy = "http://%s%s:%s/" %  (authentication, host, port)
            return http_proxy
    except Exception:
        logging.exception("failed to get proxy from gconf")
    return None

def encode_for_xml(unicode_data, encoding="ascii"):
    """ encode a given string for xml """
    return unicode_data.encode(encoding, 'xmlcharrefreplace')

def decode_xml_char_reference(s):
    """ takes a string like 
        'Search&#x2026;' 
        and converts it to
        'Search...'
    """
    import re
    p = re.compile("\&\#x(\d\d\d\d);")
    return p.sub(r"\u\1", s).decode("unicode-escape")
    
def unescape(text):
    """
    unescapes the given text
    """
    return xml.sax.saxutils.unescape(text, ESCAPE_ENTITIES)

def get_current_arch():
    return apt_pkg.config.find("Apt::Architecture")

if __name__ == "__main__":
    s = decode_xml_char_reference('Search&#x2026;')
    print s
    print type(s)
    print unicode(s)