#!/usr/bin/env python2
# -*- coding: utf-8 -*-
'''
This extension strips everything which is not selected from
the current svg, saves it and
calls VisiCut on it.

Copyright (C) 2012 Thomas Oster, thomas.oster@rwth-aachen.de
Copyright (C) 2014-2018 Max Gaukler, development@maxgaukler.de

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
'''

import sys
import os
import re
import subprocess
from subprocess import Popen
import traceback
import tempfile
import unicodedata
import codecs

DEVNULL = open(os.devnull, 'w')

SINGLEINSTANCEPORT = 6543

# if on linux, add display variable to singleinstanceport
if (sys.platform == "linux"):
    d = os.environ.get("DISPLAY")
    if (d != None):
        d = d.split(':')[1].split('.')[0]
        SINGLEINSTANCEPORT += int(d)

# if on Windows with Terminal Services, choose a singleinstanceport unique for each session ID.
# note: we cannot use SESSIONNAME here because it can change when disconnecting and reconnecting a session!
#       (think of SESSIONNAME like a display that can be connected to different session IDs)
if (sys.platform == "win32"):
    d = os.environ.get("SESSIONNAME")
    if d == None:
        # no Terminal Services installed
        pass
    else:
        # get ID by parsing output of `query session`:
        # the relevant line looks like:
        # >rdp-tcp#0         Fablab                   12  Aktiv   rdpwd
        # where "12" is the ID.

        def querySession():
            query = Popen(["query", "session"], stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
            return query.communicate()[0]
        try:
            query_output = None
            query_output = querySession()
        except WindowsError:
            # as if this is not easy enough, we have to invoke some black magic to make this work with 32bit python on 64bit windows
            # (query.exe lives in Windows/System32 folder, but access to this is redirected to the Syswow64 folder for 32bit applications, where no query.exe exists!)
            # https://mail.python.org/pipermail/python-win32/2009-June/009263.html
            import ctypes
            k32 = ctypes.windll.kernel32
            wow64 = ctypes.c_long(0)
            # disable system32 redirection
            try:
                k32.Wow64DisableWow64FsRedirection(ctypes.byref(wow64))
                # do what we want
                try:
                    query_output = querySession()
                except WindowsError:
                    # in some cases query doesn't exist on windows 7 if terminal services isn't installed
                    pass
                finally:
                    # re-enable system32 redirection
                    k32.Wow64EnableWow64FsRedirection(wow64)
            except AttributeError:
                pass

        if query_output is not None:
            id = None
            for line in query_output.splitlines():
                if line.startswith(">"):  # current session
                    numbers = re.findall("[0-9]+", line)
                    id = int(numbers[-1])  # ID is the last number on the line
                    break
            assert id,  "could not parse TS session ID"
            assert 0 < id < 1000
            SINGLEINSTANCEPORT += 2 + id

# if Visicut or Inkscape cannot be found, change these lines here to VISICUTDIR="C:/Programs/Visicut" or wherever you installed it.
# please use forward slashes (/), not backslashes (\).
#
# example:
# VISICUTDIR="C:/Program Files (x86)/VisiCut/"
# INKSCAPEDIR="C:/Program Files (x86)/Inkscape/"
VISICUTDIR = ""
INKSCAPEDIR = ""

# wether to add (true) or replace (false) current visicut's content
IMPORT = "true"
# Store the IDs of selected Elements
elements = []

for arg in sys.argv[1:]:
    if arg[0] == "-":
        if len(arg) >= 5 and arg[0:5] == "--id=":
            elements += [arg[5:]]
        elif len(arg) >= 13 and arg[0:13] == "--visicutbin=":
            # unused
            pass
            # VISICUTBIN=arg[13:]
        elif len(arg) >= 9 and arg[0:9] == "--import=":
            IMPORT = arg[9:]
        else:
            arguments += [arg]
    else:
        filename = arg

# find executable in the PATH


def which(program, extraPaths=[]):
    pathlist = extraPaths + os.environ["PATH"].split(os.pathsep) + [""]
    if "nt" in os.name:  # Windows
        if not program.lower().endswith(".exe"):
            program += ".exe"
        programfiles = os.environ.get("ProgramFiles", "C:\\Program Files\\")
        programfiles86 = os.environ.get("ProgramFiles(x86)", "C:\\Program Files (x86)\\")
        # also look in %ProgramFiles%/yourProgram/yourProgram.exe
        pathlist += [programfiles + "\\" + program + "\\", programfiles86 + "\\" + program + "\\"]

    def is_exe(fpath):
        return os.path.isfile(fpath) and (os.access(fpath, os.X_OK) or fpath.endswith(".exe"))
    for path in pathlist:
        exe_file = os.path.join(path, program)
        if is_exe(exe_file):
            return exe_file
    raise Exception("Cannot find executable {0} in PATH={1}.\n\n"
                    "Please report this bug on https://github.com/t-oster/VisiCut/issues\n\n"
                    "For a quick fix: Set VISICUTDIR and INKSCAPEDIR in "
                    "{2}"
                    .format(str(program), str(pathlist), os.path.realpath(__file__)))

# def removeAllButThem(element, elements):
# if element.get('id') in elements:
#  return True
# else:
#  keepSubtree = False
#  for e in element:
#   if not removeAllButThem(e, elements):
#    element.remove(e)
#   else:
#    keepSubtree = True
#  return keepSubtree
#
# Strip SVG to only contain selected elements
# LXML version
# def stripSVG_lxml(src,dest,elements):
# try:
#  from lxml import etree
#  tree = etree.parse(src)
#  if len(elements) > 0:
#   removeAllButThem(tree.getroot(), elements)
#  tree.write(dest)
# except:
#  sys.stderr.write("Python-LXML not installed. Can only send complete SVG\n")
#  import shutil
#  shutil.copyfile(src, dest)



def inkscape_version():
    """determine if Inkscape is version 0 or 1"""
    version = subprocess.check_output([INKSCAPEBIN, "--version"],  stderr=DEVNULL)
    assert version.startswith("Inkscape ")
    if version.startswith("Inkscape 0"):
        return 0
    else:
        return 1
    


# Strip SVG to only contain selected elements, convert objects to paths, unlink clones
# Inkscape version: takes care of special cases where the selected objects depend on non-selected ones.
# Examples are linked clones, flowtext limited to a shape and linked flowtext boxes (overflow into the next box).
#
# Inkscape is called with certain "verbs" (gui actions) to do the required cleanup
# The idea is similar to http://bazaar.launchpad.net/~nikitakit/inkscape/svg2sif/view/head:/share/extensions/synfig_prepare.py#L181 , but more primitive - there is no need for more complicated preprocessing here
def stripSVG_inkscape(src, dest, elements):
    version = inkscape_version()
    
    # create temporary file for opening with inkscape.
    # delete this file later so that it will disappear from the "recently opened" list.
    tmpfile = tempfile.NamedTemporaryFile(delete=False, prefix='temp-visicut-', suffix='.svg')
    tmpfile.close()
    tmpfile = tmpfile.name
    import shutil
    shutil.copyfile(src, tmpfile)


    if version == 0:
        # inkscape 0.92 long-term-support release. Will be in Linux distributions until 2025 or so
        # Selection commands: select items, invert selection, delete
        selection = []
        for el in elements:
            selection += ["--select=" + el]

        if len(elements) > 0:
            # selection += ["--verb=FitCanvasToSelection"] # TODO add a user configuration option whether to keep the page size (and by this the position relative to the page)
            selection += ["--verb=EditInvertInAllLayers", "--verb=EditDelete"]


        hidegui = ["--without-gui"]

        # currently this only works with gui because of a bug in inkscape: https://bugs.launchpad.net/inkscape/+bug/843260
        hidegui = []

        command = [INKSCAPEBIN] + hidegui + [tmpfile, "--verb=UnlockAllInAllLayers", "--verb=UnhideAllInAllLayers"] + selection + ["--verb=EditSelectAllInAllLayers", "--verb=EditUnlinkClone", "--verb=ObjectToPath", "--verb=FileSave", "--verb=FileQuit"]
    else:
        # Inkscape 1.0, to be released ca 2020
        # inkscape --select=... --verbs=...
        # (see inkscape --help, inkscape --verb-list)
        command = [INKSCAPEBIN, tmpfile, "--batch-process"]
        verbs = ["ObjectToPath", "UnlockAllInAllLayers"]
        if elements: # something is selected
            # --select=object1,object2,object3,...
            command += ["--select=" + ",".join(elements)]
        else:
            verbs += ["EditSelectAllInAllLayers"]
        verbs += ["UnhideAllInAllLayers", "EditInvertInAllLayers", "EditDelete", "EditSelectAllInAllLayers", "EditUnlinkClone", "ObjectToPath", "FileSave"]
        # --verb=action1;action2;...
        command += ["--verb=" + ";".join(verbs)]
        
        
        DEBUG = False
        if DEBUG:
            # Inkscape sometimes silently ignores wrong verbs, so we need to double-check that everything's right
            for verb in verbs:
                verb_list = [line.split(":")[0] for line in subprocess.check_output([INKSCAPEBIN, "--verb-list"], stderr=DEVNULL).split("\n")]
                if verb not in verb_list:
                    sys.stderr.write("Inkscape does not have the verb '{}'. Please report this as a VisiCut bug.".format(verb))
        
    inkscape_output = "(not yet run)"
    try:
        #sys.stderr.write(" ".join(command))
        # run inkscape, buffer output
        inkscape = subprocess.Popen(command, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
        inkscape_output = inkscape.communicate()[0]
        if inkscape.returncode != 0:
            sys.stderr.write("Error: cleaning the document with inkscape failed. Something might still be shown in visicut, but it could be incorrect.\nInkscape's output was:\n" + inkscape_output)
    except:
        sys.stderr.write("Error: cleaning the document with inkscape failed. Something might still be shown in visicut, but it could be incorrect. Exception information: \n" + str(sys.exc_info()[0]) + "Inkscape's output was:\n" + inkscape_output)

    # move output to the intended destination filename
    os.rename(tmpfile, dest)


"""
Get document name (original filename) from Inkscape SVG

Inkscape saves the file to a random temporary name.
However, the original filename is stored inside the SVG.
"""


def get_original_filename(filename):
    docname = None

    # parse SVG for docname tag
    with codecs.open(filename, "r", encoding='utf-8') as f:
        for line in f:
            if 'sodipodi:docname="' in line:
                matches = re.search('sodipodi:docname="(.*).svg"', line)
                if not matches:
                    break
                try:
                    docname = matches.group(1)
                except IndexError:
                    # something is wrong with this line
                    break
                # unescape XML string
                docname = docname.replace('&lt;', '<')
                docname = docname.replace('&gt;', '>')
                docname = docname.replace('&quot;', '"')
                docname = docname.replace('&amp;', '&')

                # normalize accented characters (äöü -> aou)
                docname = unicodedata.normalize('NFKD', docname).encode('ASCII', 'ignore')
                break

    if not docname:
        # failed to read filename from SVG, return original one
        docname = os.path.basename(filename)
        if str.endswith(docname, ".svg"):
            docname = docname[:-4]
        if str.startswith(docname, "ink_ext_"):
            # inkscape temporary file, the name is useless
            docname = "new"

    # sanitize the filename:
    # filter out special characters (@/\& ...)
    docname = "".join(x for x in docname if (x.isalnum() or x in "._- "))
    docname = docname + ".svg"
    return docname

# find executable paths
import platform
if platform.system() == 'Darwin':
    VISICUTBIN = which("VisiCut.MacOS", [VISICUTDIR])
elif "nt" in os.name:  # Windows
    VISICUTBIN = which("VisiCut.exe", [VISICUTDIR])
else:
    VISICUTBIN = which("VisiCut.Linux", [VISICUTDIR, "/usr/share/visicut"])
INKSCAPEBIN = which("inkscape", [INKSCAPEDIR])

tmpdir = tempfile.mkdtemp(prefix='temp-visicut-')
dest_filename = os.path.join(tmpdir, get_original_filename(filename))

# remove all non-selected elements and convert inkscape-specific elements (text-to-path etc.)
stripSVG_inkscape(src=filename, dest=dest_filename, elements=elements)

# Try to connect to running VisiCut instance
try:
    import socket
    s = socket.socket()
    s.connect(("localhost", SINGLEINSTANCEPORT))
    if (IMPORT == "true" or IMPORT == true or IMPORT == "\"true\""):
        s.send("@" + dest_filename + "\n")
    else:
        s.send(dest_filename + "\n")
    s.close()
    sys.exit(0)
except SystemExit, e:
    sys.exit(e)
except:
    pass

# Try to start own VisiCut instance
try:
    arguments = ["--singleinstanceport", str(SINGLEINSTANCEPORT)]

    creationflags = 0
    close_fds = False
    if os.name == "nt":
        DETACHED_PROCESS = 8  # start as "daemon"
        creationflags = DETACHED_PROCESS
        close_fds = True
    else:
        try:
            import fablabchemnitz_daemonize
            daemonize.createDaemon()
        except:
            sys.stderr.write("Could not daemonize. Sorry, but Inkscape was blocked until VisiCut is closed")
    cmd = [VISICUTBIN] + arguments + [dest_filename]
    Popen(cmd, creationflags=creationflags, close_fds=close_fds)
except:
    sys.stderr.write("Can not start VisiCut (" + str(sys.exc_info()[0]) + "). Please start manually or change the VISICUTDIR variable in the Inkscape-Extension script\n")

# TODO (complicated, probably WONTFIX): cleanup temporary directories -- this is really difficult because we need to make sure that visicut no longer needs the file, even for reloading!