# -*- coding: utf-8 -*-

"""

    rhodecode.lib.compat

    ~~~~~~~~~~~~~~~~~~~~

    Python backward compatibility functions and common libs

    :created_on: Oct 7, 2011

    :author: marcink

    :copyright: (C) 2010-2010 Marcin Kuzminski <marcin@python-works.com>

    :license: GPLv3, see COPYING for more details.

"""

# 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 3 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, see <http://www.gnu.org/licenses/>.

import os

from rhodecode import __platform__, PLATFORM_WIN, __py_version__

#==============================================================================

# json

#==============================================================================

from rhodecode.lib.ext_json import json

#==============================================================================

# izip_longest

#==============================================================================

try:

    from itertools import izip_longest

except ImportError:

    import itertools

    def izip_longest(*args, **kwds):

        fillvalue = kwds.get("fillvalue")

        def sentinel(counter=([fillvalue] * (len(args) - 1)).pop):

            yield counter()  # yields the fillvalue, or raises IndexError

        fillers = itertools.repeat(fillvalue)

        iters = [itertools.chain(it, sentinel(), fillers)

                    for it in args]

        try:

            for tup in itertools.izip(*iters):

                yield tup

        except IndexError:

            pass

#==============================================================================

# OrderedDict

#==============================================================================

# Python Software Foundation License

# XXX: it feels like using the class with "is" and "is not" instead of "==" and

# "!=" should be faster.

class _Nil(object):

    def __repr__(self):

        return "nil"

    def __eq__(self, other):

        if (isinstance(other, _Nil)):

            return True

        else:

            return NotImplemented

    def __ne__(self, other):

        if (isinstance(other, _Nil)):

            return False

        else:

            return NotImplemented

_nil = _Nil()

class _odict(object):

    """Ordered dict data structure, with O(1) complexity for dict operations

    that modify one element.

    Overwriting values doesn't change their original sequential order.

    """

    def _dict_impl(self):

        return None

    def __init__(self, data=(), **kwds):

        """This doesn't accept keyword initialization as normal dicts to avoid

        a trap - inside a function or method the keyword args are accessible

        only as a dict, without a defined order, so their original order is

        lost.

        """

        if kwds:

            raise TypeError("__init__() of ordered dict takes no keyword "

                            "arguments to avoid an ordering trap.")

        self._dict_impl().__init__(self)

        # If you give a normal dict, then the order of elements is undefined

        if hasattr(data, "iteritems"):

            for key, val in data.iteritems():

                self[key] = val

        else:

            for key, val in data:

                self[key] = val

    # Double-linked list header

    def _get_lh(self):

        dict_impl = self._dict_impl()

        if not hasattr(self, '_lh'):

            dict_impl.__setattr__(self, '_lh', _nil)

        return dict_impl.__getattribute__(self, '_lh')

    def _set_lh(self, val):

        self._dict_impl().__setattr__(self, '_lh', val)

    lh = property(_get_lh, _set_lh)

    # Double-linked list tail

    def _get_lt(self):

    def ritems(self):

        """List of the (key, value) in reversed order.

        """

        return list(self.riteritems())

    def firstkey(self):

        if self:

            return self._dict_impl().__getattribute__(self, 'lh')

        else:

            raise KeyError("'firstkey(): ordered dictionary is empty'")

    def lastkey(self):

        if self:

            return self._dict_impl().__getattribute__(self, 'lt')

        else:

            raise KeyError("'lastkey(): ordered dictionary is empty'")

    def as_dict(self):

        return self._dict_impl()(self.items())

    def _repr(self):

        """_repr(): low level repr of the whole data contained in the odict.

        Useful for debugging.

        """

        dict_impl = self._dict_impl()

        form = "odict low level repr lh,lt,data: %r, %r, %s"

        return form % (dict_impl.__getattribute__(self, 'lh'),

                       dict_impl.__getattribute__(self, 'lt'),

                       dict_impl.__repr__(self))

class OrderedDict(_odict, dict):

    def _dict_impl(self):

        return dict

#==============================================================================

# OrderedSet

#==============================================================================

from sqlalchemy.util import OrderedSet

#==============================================================================

# kill FUNCTIONS

#==============================================================================

if __platform__ in PLATFORM_WIN:

    import ctypes

    def kill(pid, sig):

        """kill function for Win32"""

        kernel32 = ctypes.windll.kernel32

        handle = kernel32.OpenProcess(1, 0, pid)

        return (0 != kernel32.TerminateProcess(handle, 0))

else:

    kill = os.kill

#==============================================================================

# itertools.product

#==============================================================================

try:

    from itertools import product

except ImportError:

    def product(*args, **kwds):

        # product('ABCD', 'xy') --> Ax Ay Bx By Cx Cy Dx Dy

        # product(range(2), repeat=3) --> 000 001 010 011 100 101 110 111

        pools = map(tuple, args) * kwds.get('repeat', 1)

        result = [[]]

        for pool in pools:

            result = [x + [y] for x in result for y in pool]

        for prod in result:

            yield tuple(prod)

#==============================================================================

# BytesIO

#==============================================================================

try:

    from io import BytesIO

except ImportError:

    from cStringIO import StringIO as BytesIO

#==============================================================================

# bytes

#==============================================================================

if __py_version__ >= (2, 6):

    _bytes = bytes

else:

    # in py2.6 bytes is a synonim for str

    _bytes = str

#==============================================================================

# deque

#==============================================================================

if __py_version__ >= (2, 6):

    from collections import deque

else:

    #need to implement our own deque with maxlen

    class deque(object):

        def __init__(self, iterable=(), maxlen= -1):

            if not hasattr(self, 'data'):

                self.left = self.right = 0

                self.data = {}

            self.maxlen = maxlen or -1

            self.extend(iterable)

        def append(self, x):

            self.data[self.right] = x

            self.right += 1

            if self.maxlen != -1 and len(self) > self.maxlen:

                self.popleft()

        def appendleft(self, x):

            self.left -= 1

            self.data[self.left] = x

            if self.maxlen != -1 and len(self) > self.maxlen:

                self.pop()

        def pop(self):

            if self.left == self.right:

                raise IndexError('cannot pop from empty deque')

            self.right -= 1

            elem = self.data[self.right]

            del self.data[self.right]

            return elem

        def popleft(self):

            if self.left == self.right:

                raise IndexError('cannot pop from empty deque')

            elem = self.data[self.left]

            del self.data[self.left]

            self.left += 1

            return elem

        def clear(self):

            self.data.clear()

            self.left = self.right = 0

        def extend(self, iterable):

            for elem in iterable:

                self.append(elem)

        def extendleft(self, iterable):

            for elem in iterable:

                self.appendleft(elem)

        def rotate(self, n=1):

            if self:

                n %= len(self)

                for i in xrange(n):

                    self.appendleft(self.pop())

        def __getitem__(self, i):

            if i < 0:

                i += len(self)

            try:

                return self.data[i + self.left]

            except KeyError:

                raise IndexError

        def __setitem__(self, i, value):

            if i < 0:

                i += len(self)

            try:

                self.data[i + self.left] = value

            except KeyError:

                raise IndexError

        def __delitem__(self, i):

            size = len(self)

            if not (-size <= i < size):

                raise IndexError

            data = self.data

            if i < 0:

                i += size

            for j in xrange(self.left + i, self.right - 1):

                data[j] = data[j + 1]

            self.pop()

        def __len__(self):

            return self.right - self.left

        def __cmp__(self, other):

            if type(self) != type(other):

                return cmp(type(self), type(other))

            return cmp(list(self), list(other))

        def __repr__(self, _track=[]):

            if id(self) in _track:

                return '...'

            _track.append(id(self))

            r = 'deque(%r, maxlen=%s)' % (list(self), self.maxlen)

            _track.remove(id(self))

            return r

        def __getstate__(self):

            return (tuple(self),)

        def __setstate__(self, s):

            self.__init__(s[0])

        def __hash__(self):

            raise TypeError

        def __copy__(self):

            return self.__class__(self)

        def __deepcopy__(self, memo={}):

            from copy import deepcopy

            result = self.__class__()

            memo[id(self)] = result

            result.__init__(deepcopy(tuple(self), memo))

            return result

#==============================================================================

# threading.Event

#==============================================================================

if __py_version__ >= (2, 6):

    from threading import Event, Thread

else:

    def Event(*args, **kwargs):

        return _Event(*args, **kwargs)

    class _Event(_Verbose):

        # After Tim Peters' event class (without is_posted())

        def __init__(self, verbose=None):

            _Verbose.__init__(self, verbose)

            self.__cond = Condition(Lock())

            self.__flag = False

        def isSet(self):

            return self.__flag

        is_set = isSet

        def set(self):

            self.__cond.acquire()

            try:

                self.__flag = True

                self.__cond.notify_all()

            finally:

                self.__cond.release()

        def clear(self):

            self.__cond.acquire()

            try:

                self.__flag = False

            finally:

                self.__cond.release()

        def wait(self, timeout=None):

            self.__cond.acquire()

            try:

                if not self.__flag:

                    self.__cond.wait(timeout)

            finally:

                self.__cond.release()

'''

Module provides a class allowing to wrap communication over subprocess.Popen

input, output, error streams into a meaningfull, non-blocking, concurrent

stream processor exposing the output data as an iterator fitting to be a

return value passed by a WSGI applicaiton to a WSGI server per PEP 3333.

Copyright (c) 2011  Daniel Dotsenko <dotsa@hotmail.com>

This file is part of git_http_backend.py Project.

git_http_backend.py Project is free software: you can redistribute it and/or

modify it under the terms of the GNU Lesser General Public License as

published by the Free Software Foundation, either version 2.1 of the License,

or (at your option) any later version.

git_http_backend.py Project 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 Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License

along with git_http_backend.py Project.

If not, see <http://www.gnu.org/licenses/>.

'''

import os

import subprocess

class StreamFeeder(Thread):

    """

    Normal writing into pipe-like is blocking once the buffer is filled.

    This thread allows a thread to seep data from a file-like into a pipe

    without blocking the main thread.

    We close inpipe once the end of the source stream is reached.

    """

    def __init__(self, source):

        super(StreamFeeder, self).__init__()

        self.daemon = True

        filelike = False

        self.bytes = _bytes()

            self.bytes = _bytes(source)

        else:  # can be either file pointer or file-like

            if type(source) in (int, long):  # file pointer it is

                ## converting file descriptor (int) stdin into file-like

                try:

                    source = os.fdopen(source, 'rb', 16384)

                except Exception:

                    pass

            # let's see if source is file-like by now

            try:

                filelike = source.read

            except Exception:

                pass

        if not filelike and not self.bytes:

            raise TypeError("StreamFeeder's source object must be a readable "

                            "file-like, a file descriptor, or a string-like.")

        self.source = source

        self.readiface, self.writeiface = os.pipe()

    def run(self):

        t = self.writeiface

        if self.bytes:

            os.write(t, self.bytes)

        else:

            s = self.source

            b = s.read(4096)

            while b:

                os.write(t, b)

                b = s.read(4096)

        os.close(t)

    @property

    def output(self):

        return self.readiface

class InputStreamChunker(Thread):

    def __init__(self, source, target, buffer_size, chunk_size):

        super(InputStreamChunker, self).__init__()

        self.daemon = True  # die die die.

        self.source = source

        self.target = target

        self.chunk_count_max = int(buffer_size / chunk_size) + 1

        self.chunk_size = chunk_size

        self.data_added = Event()

        self.data_added.clear()

        self.keep_reading = Event()

        self.keep_reading.set()

        self.EOF = Event()

        self.EOF.clear()

        self.go = Event()

        self.go.set()

    def stop(self):

        self.go.clear()

        self.EOF.set()

        try:

            # this is not proper, but is done to force the reader thread let

            # go of the input because, if successful, .close() will send EOF

            # down the pipe.

            self.source.close()

        except:

            pass

    def run(self):

        s = self.source

        t = self.target

        cs = self.chunk_size

        ccm = self.chunk_count_max

        kr = self.keep_reading

        da = self.data_added

        go = self.go

        b = s.read(cs)

        while b and go.is_set():

            if len(t) > ccm:

                kr.clear()

                kr.wait(2)

#                # this only works on 2.7.x and up

#                if not kr.wait(10):

#                    raise Exception("Timed out while waiting for input to be read.")

                # instead we'll use this

                if len(t) > ccm + 3:

                    raise IOError("Timed out while waiting for input from subprocess.")

            t.append(b)

            da.set()

            b = s.read(cs)

        self.EOF.set()

        da.set()  # for cases when done but there was no input.