#!/usr/bin/python
# -*- coding: utf-8 -*-
#
# Copyright (C) 2011 Sebastien Helleu <flashcode@flashtux.org>
#
# This file is part of QWeeChat, a Qt remote GUI for WeeChat.
#
# QWeeChat 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; either version 3 of the License, or
# (at your option) any later version.
#
# QWeeChat 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 QWeeChat.  If not, see <http://www.gnu.org/licenses/>.
#

#
# Decode binary messages received from WeeChat/relay.
#
# For info about protocol and format of messages, please read document "WeeChat Relay Protocol",
# available at:  http://www.weechat.org/doc/
#
# History:
#
# 2011-11-23, Sebastien Helleu <flashcode@flashtux.org>:
#     start dev
#

import struct, zlib

class WeechatObject:
    def __init__(self, objtype, value):
        self.objtype = objtype;
        self.value = value

    def _str_value(self, v):
        if type(v) is str and not v is None:
            return '\'%s\'' % v
        return str(v)

    def _str_value_hdata(self):
        lines = ['',
                 '  keys: %s' % str(self.value['keys']),
                 '  path: %s' % str(self.value['path'])]
        for i, item in enumerate(self.value['items']):
            lines.append('  item %d:' % (i + 1))
            lines.append('\n'.join(['    %s: %s' % (key, self._str_value(value)) for key, value in iter(sorted(item.iteritems()))]))
        return '\n'.join(lines)

    def _str_value_infolist(self):
        lines = ['', '  name: %s' % self.value['name']]
        for i, item in enumerate(self.value['items']):
            lines.append('  item %d:' % (i + 1))
            lines.append('\n'.join(['    %s: %s' % (key, self._str_value(value)) for key, value in iter(sorted(item.iteritems()))]))
        return '\n'.join(lines)

    def _str_value_other(self):
        return self._str_value(self.value)

    def __str__(self):
        self._obj_cb = {'hda': self._str_value_hdata,
                        'lis': self._str_value_infolist,
                        }
        return '%s: %s' % (self.objtype, self._obj_cb.get(self.objtype, self._str_value_other)())


class WeechatObjects(list):
    def __str__(self):
        return '\n'.join([str(obj) for obj in self])


class WeechatMessage:
    def __init__(self, size, size_uncompressed, compression, uncompressed, msgid, objects):
        self.size = size
        self.size_uncompressed = size_uncompressed
        self.compression = compression
        self.uncompressed = uncompressed
        self.msgid = msgid
        self.objects = objects

    def __str__(self):
        if self.compression != 0:
            return 'size: %d/%d (%d%%), id=\'%s\', objects:\n%s' % (
                self.size, self.size_uncompressed,
                100 - ((self.size * 100) / self.size_uncompressed),
                self.msgid, self.objects)
        else:
            return 'size: %d, id=\'%s\', objects:\n%s' % (self.size, self.msgid, self.objects)


class Protocol:
    """Decode binary message received from WeeChat/relay."""

    def __init__(self):
        self._obj_cb = {'chr': self._obj_char,
                        'int': self._obj_int,
                        'lon': self._obj_long,
                        'str': self._obj_str,
                        'buf': self._obj_buffer,
                        'ptr': self._obj_ptr,
                        'tim': self._obj_time,
                        'hda': self._obj_hdata,
                        'inf': self._obj_info,
                        'lis': self._obj_infolist,
                        }

    def _obj_len_data(self, length_size):
        """Read length (1 or 4 bytes), then value with this length."""
        if len(self.data) < length_size:
            self.data = ''
            return None
        if length_size == 1:
            length = struct.unpack('B', self.data[0:1])[0]
            self.data = self.data[1:]
        else:
            length = self._obj_int()
        if length < 0:
            return None
        if length > 0:
            value = self.data[0:length]
            self.data = self.data[length:]
        else:
            value = ''
        return value

    def _obj_char(self):
        """Read a char in data."""
        if len(self.data) < 1:
            return 0
        value = struct.unpack('b', self.data[0:1])[0]
        self.data = self.data[1:]
        return value

    def _obj_int(self):
        """Read an integer in data (4 bytes)."""
        if len(self.data) < 4:
            self.data = ''
            return 0
        value = struct.unpack('>i', self.data[0:4])[0]
        self.data = self.data[4:]
        return value

    def _obj_long(self):
        """Read a long integer in data (length on 1 byte + value as string)."""
        value = self._obj_len_data(1)
        if value is None:
            return None
        return int(str(value))

    def _obj_str(self):
        """Read a string in data (length on 4 bytes + content)."""
        value = self._obj_len_data(4)
        if value is None:
            return None
        return str(value)

    def _obj_buffer(self):
        """Read a buffer in data (length on 4 bytes + data)."""
        return self._obj_len_data(4)

    def _obj_ptr(self):
        """Read a pointer in data (length on 1 byte + value as string)."""
        value = self._obj_len_data(1)
        if value is None:
            return None
        return '0x%s' % str(value)

    def _obj_time(self):
        """Read a time in data (length on 1 byte + value as string)."""
        value = self._obj_len_data(1)
        if value is None:
            return None
        return str(value)

    def _obj_hdata(self):
        """Read a hdata in data."""
        path = self._obj_str()
        keys = self._obj_str()
        count = self._obj_int()
        list_path = path.split('/')
        list_keys = keys.split(',')
        keys_types = []
        dict_keys = {}
        for key in list_keys:
            items = key.split(':')
            keys_types.append(items)
            dict_keys[items[0]] = items[1]
        items = []
        for i in xrange(0, count):
            item = {}
            pointers = []
            for p in xrange(0, len(list_path)):
                pointers.append(self._obj_ptr())
            for key, objtype in keys_types:
                item[key] = self._obj_cb[objtype]()
            item['__path'] = pointers
            items.append(item)
        return {'path': list_path,
                'keys': dict_keys,
                'count': count,
                'items': items,
                }

    def _obj_info(self):
        """Read an info in data."""
        name = self._obj_str()
        value = self._obj_str()
        return (name, value)

    def _obj_infolist(self):
        """Read an infolist in data."""
        name = self._obj_str()
        count_items = self._obj_int()
        items = []
        for i in xrange(0, count_items):
            count_vars = self._obj_int()
            variables = {}
            for v in xrange(0, count_vars):
                var_name = self._obj_str()
                var_type = self._obj_type()
                var_value = self._obj_cb[var_type]()
                variables[var_name] = var_value
            items.append(variables)
        return {'name': name, 'items': items}

    def _obj_type(self):
        """Read type in data (3 chars)."""
        if len(self.data) < 3:
            self.data = ''
            return ''
        objtype = str(self.data[0:3])
        self.data = self.data[3:]
        return objtype

    def decode(self, data):
        """Decode binary data and return list of objects."""
        self.data = data
        size = len(self.data)
        size_uncompressed = size
        uncompressed = None
        # uncompress data (if it is compressed)
        compression = struct.unpack('b', self.data[4:5])[0]
        if compression:
            uncompressed = zlib.decompress(self.data[5:])
            size_uncompressed = len(uncompressed) + 5
            uncompressed = '%s%s%s' % (struct.pack('>i', size_uncompressed), struct.pack('b', 0), uncompressed)
            self.data = uncompressed
        # skip length and compression flag
        self.data = self.data[5:]
        # read id
        msgid = self._obj_str()
        if msgid is None:
            msgid = ''
        # read objects
        objects = WeechatObjects()
        while len(self.data) > 0:
            objtype = self._obj_type()
            value = self._obj_cb[objtype]()
            objects.append(WeechatObject(objtype, value))
        return WeechatMessage(size, size_uncompressed, compression, uncompressed, msgid, objects)


def hex_and_ascii(data, bytes_per_line=10):
    """Convert a QByteArray to hex + ascii output."""
    num_lines = ((len(data) - 1) / bytes_per_line) + 1
    if num_lines == 0:
        return ''
    lines = []
    for i in xrange(0, num_lines):
        str_hex = []
        str_ascii = []
        for char in data[i*bytes_per_line:(i*bytes_per_line)+bytes_per_line]:
            byte = struct.unpack('B', char)[0]
            str_hex.append('%02X' % int(byte))
            if byte >= 32 and byte <= 127:
                str_ascii.append(char)
            else:
                str_ascii.append('.')
        fmt = '%%-%ds %%s' % ((bytes_per_line * 3) - 1)
        lines.append(fmt % (' '.join(str_hex), ''.join(str_ascii)))
    return '\n'.join(lines)