#
#  This file is part of Documancer (http://documancer.sf.net)
#
#  Copyright (C) 2002-2005 Vaclav Slavik
#
#  This program is free software; you can redistribute it and/or modify
#  it under the terms of the GNU General Public License version 2 as
#  published by the Free Software Foundation.
#
#  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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
#
#  $Id: utils.py,v 1.15 2005/01/30 18:29:31 vaclavslavik Exp $
#
#  Misc utility functions
#


import os, os.path, string, urllib, pipes, sys

def getConfigDir():
    if sys.platform == 'win32':
        import pythoncom
        from win32com.shell import shell
        from win32com.shell import shellcon
        id = shellcon.CSIDL_APPDATA
        try:
            appdata = shell.SHGetSpecialFolderPath(0, id)
        except pythoncom.com_error:
            idl = shell.SHGetSpecialFolderLocation(0, id)
            appdata = shell.SHGetPathFromIDList(idl)
        return os.path.join(appdata, 'Documancer', '')
    else:
        cdir = os.path.expanduser('~/.documancer/')
        if not os.path.isdir(cdir):
           os.mkdir(cdir)
        return cdir
    
def getBooksDir():
    bookdir = getConfigDir() + 'books'
    if not os.path.isdir(bookdir):
        os.mkdir(bookdir)
    return bookdir

def getDocumancerHome():
    return os.environ['DOCUMANCER_HOME']

def mangleBookName(name):
    return urllib.quote(name, "")

def demangleBookName(name):
    return urllib.unquote(name)
                
def bookNameToFileName(name):
    """Converts book name into a 'nice' filename."""
    x = name.lower()
    for i in ' `~@#$%^&*()\\|[]{}:;"\'<>,./?':
        # FIXME - use regex to do the substitution!
        x = x.replace(i, '-')
    return x


DEFAULT_PORT_RANGE = '49152-65535'

portsAvailable = None

def findUnusedPort():
    """Finds some currently unused port."""
    import socket, errno, utils
    import random
    global portsAvailable

    def portUsed(port):
        used = 0
        s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        try:
            s.bind(('', port))
        except socket.error, (err, desc):
            if err == errno.EADDRINUSE:
                used = 1
        s.close()
        return used

    # Find out what the allowed ports range is:
    if portsAvailable == None:
        r = utils.config().Read('/Backend/ports_range', DEFAULT_PORT_RANGE)
        portFrom = int(r.split('-')[0])
        portTo = int(r.split('-')[1])
        portsAvailable = range(portFrom, portTo+1)
    
    while 1:
        i = random.randrange(0, len(portsAvailable))
        p = portsAvailable[i]
        del portsAvailable[i]
        if not portUsed(p):
            return p

    return None

usedPorts = {}

def getServerPort(purpose = 'html_server'):
    global usedPorts
    if purpose not in usedPorts:
        usedPorts[purpose] = findUnusedPort()
    return usedPorts[purpose]


__configObject = None
def config():
    global __configObject
    if __configObject == None:
        import wxPython.wx
        if sys.platform == 'win32':
            cfg = wxPython.wx.wxConfig('Documancer', 'Vaclav Slavik')
        else:
            cfg = wxPython.wx.wxConfig('Documancer', 'Vaclav Slavik',
                           getConfigDir()+'config.ini', '/etc/documancer.conf')
        wxPython.wx.wxConfigBase_Set(cfg)
        __configObject = cfg    
    return __configObject


# --------------------------------------------------------------------------
#                         UI callback structure
# --------------------------------------------------------------------------

class __UiCallbackNoop:
    def error(self, msg): pass
    def errorPrompt(self, msg): pass #create a GUI prompt for the error
    def showBusyIndicator(self): pass
    def hideBusyIndicator(self): pass
    def setBusyText(self, text): pass

# This variable contains UI interface functions, so that UI elements can be
# used by the backend (which doesn't know which UI is being used)
uiCallback = __UiCallbackNoop()