# Copyright (c) 2003-2007 LOGILAB S.A. (Paris, FRANCE).
# http://www.logilab.fr/ -- mailto:contact@logilab.fr

# 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; either version 2 of the License, or (at your option) any later
# version.

# 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.
"""
Some shell/term utilities, useful to write some python scripts instead of shell
scripts
"""

import os        
import glob
import shutil
import sys
import tempfile
import time
from os.path import exists, isdir, islink, basename, join, walk

from logilab.common import STD_BLACKLIST

def mv(source, destination, _action=shutil.move):
    """a shell like mv, supporting wildcards
    """
    sources = glob.glob(source)
    if len(sources) > 1:
        assert isdir(destination)
        for filename in sources:
            _action(filename, join(destination, basename(filename)))
    else:
        try:
            source = sources[0]
        except IndexError:
            raise OSError('No file matching %s' % source)
        if isdir(destination) and exists(destination):
            destination = join(destination, basename(source))
        try:
            _action(source, destination)
        except OSError, ex:
            raise OSError('Unable to move %r to %r (%s)' % (
                source, destination, ex))
        
def rm(*files):
    """a shell like rm, supporting wildcards
    """
    for wfile in files:
        for filename in glob.glob(wfile):
            if islink(filename):
                os.remove(filename)
            elif isdir(filename):
                shutil.rmtree(filename)
            else:
                os.remove(filename)
    
def cp(source, destination):
    """a shell like cp, supporting wildcards
    """
    mv(source, destination, _action=shutil.copy)


def find(directory, exts, exclude=False, blacklist=STD_BLACKLIST):
    """recursivly find files ending with the given extensions from the directory

    :type directory: str
    :param directory:
      directory where the search should start

    :type exts: basestring or list or tuple
    :param exts:
      extensions or lists or extensions to search

    :type exclude: boolean
    :param exts:
      if this argument is True, returning files NOT ending with the given
      extensions

    :type blacklist: list or tuple
    :param blacklist:
      optional list of files or directory to ignore, default to the value of
      `logilab.common.STD_BLACKLIST`

    :rtype: list
    :return:
      the list of all matching files
    """
    if isinstance(exts, basestring):
        exts = (exts,)
    if exclude:
        def match(filename, exts):
            for ext in exts:
                if filename.endswith(ext):
                    return False
            return True
    else:
        def match(filename, exts):
            for ext in exts:
                if filename.endswith(ext):
                    return True
            return False
    def func(files, directory, fnames):
        """walk handler"""
        # remove files/directories in the black list
        for norecurs in blacklist:
            try:
                fnames.remove(norecurs)
            except ValueError:
                continue
        for filename in fnames:
            src = join(directory, filename)
            if isdir(src):
                continue
            if match(filename, exts):
                files.append(src)
    files = []
    walk(directory, func, files)
    return files


class Execute:
    """This is a deadlock safe version of popen2 (no stdin), that returns
    an object with errorlevel, out and err
    """
    
    def __init__(self, command):
        outfile = tempfile.mktemp()
        errfile = tempfile.mktemp()
        self.status = os.system("( %s ) >%s 2>%s" %
                                (command, outfile, errfile)) >> 8
        self.out = open(outfile,"r").read()
        self.err = open(errfile,"r").read()
        os.remove(outfile)
        os.remove(errfile)


def acquire_lock(lock_file, max_try=10, delay=10):
    """acquire a lock represented by a file on the file system"""
    count = 0
    while max_try <= 0 or count < max_try:
        if not exists(lock_file):
            break
        count += 1
        time.sleep(delay)
    else:
        raise Exception('Unable to acquire %s' % lock_file)
    stream = open(lock_file, 'w')
    stream.write(str(os.getpid()))
    stream.close()
    
def release_lock(lock_file):
    """release a lock represented by a file on the file system"""
    os.remove(lock_file)


class ProgressBar(object):
    """a simple text progression bar"""
    
    def __init__(self, nbops, size=20., stream=sys.stdout):
        self._dotevery = max(nbops / size, 1)
        self._fstr = '\r[%-20s]'
        self._dotcount, self._dots = 1, []
        self._stream = stream

    def update(self):
        """update the progression bar"""
        self._dotcount += 1
        if self._dotcount >= self._dotevery:
            self._dotcount = 1
            self._dots.append('.')
            self._stream.write(self._fstr % ''.join(self._dots))
            self._stream.flush()