#!/usr/bin/env python
# -*- coding: utf-8 -*-
#
# Copyright 2005-2009 Zuza Software Foundation
#
# This file is part of the Translate Toolkit.
#
# 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, see <http://www.gnu.org/licenses/>.

"""Module for handling XLIFF files for translation.

The official recommendation is to use the extention .xlf for XLIFF files.
"""

from lxml import etree

from translate.misc.multistring import multistring
from translate.misc.xml_helpers import *
from translate.storage import base, lisa
from translate.storage.lisa import getXMLspace
from translate.storage.placeables.lisa import xml_to_strelem, strelem_to_xml

# TODO: handle translation types

class xliffunit(lisa.LISAunit):
    """A single term in the xliff file."""

    rootNode = "trans-unit"
    languageNode = "source"
    textNode = ""
    namespace = 'urn:oasis:names:tc:xliff:document:1.1'

    _default_xml_space = "default"

    #TODO: id and all the trans-unit level stuff

    def __init__(self, source, empty=False, **kwargs):
        """Override the constructor to set xml:space="preserve"."""
        if empty:
            return
        super(xliffunit, self).__init__(source, empty, **kwargs)
        lisa.setXMLspace(self.xmlelement, "preserve")

    def createlanguageNode(self, lang, text, purpose):
        """Returns an xml Element setup with given parameters."""

        #TODO: for now we do source, but we have to test if it is target, perhaps 
        # with parameter. Alternatively, we can use lang, if supplied, since an xliff 
        #file has to conform to the bilingual nature promised by the header.
        assert purpose
        langset = etree.Element(self.namespaced(purpose))
        #TODO: check language
#        lisa.setXMLlang(langset, lang)

#        self.createPHnodes(langset, text)
        langset.text = text
        return langset

    def getlanguageNodes(self):
        """We override this to get source and target nodes."""
        source = None
        target = None
        nodes = []
        try:
            source = self.xmlelement.iterchildren(self.namespaced(self.languageNode)).next()
            target = self.xmlelement.iterchildren(self.namespaced('target')).next()
            nodes = [source, target]
        except StopIteration:
            if source is not None:
                nodes.append(source)
            if not target is None:
                nodes.append(target)
        return nodes

    def set_rich_source(self, value, sourcelang='en'):
        sourcelanguageNode = self.get_source_dom()
        if sourcelanguageNode is None:
            sourcelanguageNode = self.createlanguageNode(sourcelang, u'', "source")
            self.set_source_dom(sourcelanguageNode)

        # Clear sourcelanguageNode first
        for i in range(len(sourcelanguageNode)):
            del sourcelanguageNode[0]
        sourcelanguageNode.text = None

        strelem_to_xml(sourcelanguageNode, value[0])

    def get_rich_source(self):
        #rsrc = xml_to_strelem(self.source_dom)
        #logging.debug('rich source: %s' % (repr(rsrc)))
        #from dubulib.debug.misc import print_stack_funcs
        #print_stack_funcs()
        return [xml_to_strelem(self.source_dom, getXMLspace(self.xmlelement, self._default_xml_space))]
    rich_source = property(get_rich_source, set_rich_source)

    def set_rich_target(self, value, lang='xx', append=False):
        if value is None:
            self.set_target_dom(self.createlanguageNode(lang, u'', "target"))
            return

        languageNode = self.get_target_dom()
        if languageNode is None:
            languageNode = self.createlanguageNode(lang, u'', "target")
            self.set_target_dom(languageNode, append)

        # Clear languageNode first
        for i in range(len(languageNode)):
            del languageNode[0]
        languageNode.text = None

        strelem_to_xml(languageNode, value[0])

    def get_rich_target(self, lang=None):
        """retrieves the "target" text (second entry), or the entry in the
        specified language, if it exists"""
        return [xml_to_strelem(self.get_target_dom(lang), getXMLspace(self.xmlelement, self._default_xml_space))]
    rich_target = property(get_rich_target, set_rich_target)

    def addalttrans(self, txt, origin=None, lang=None, sourcetxt=None, matchquality=None):
        """Adds an alt-trans tag and alt-trans components to the unit.

        @type txt: String
        @param txt: Alternative translation of the source text.
        """

        #TODO: support adding a source tag ad match quality attribute.  At 
        # the source tag is needed to inject fuzzy matches from a TM.
        if isinstance(txt, str):
            txt = txt.decode("utf-8")
        alttrans = etree.SubElement(self.xmlelement, self.namespaced("alt-trans"))
        lisa.setXMLspace(alttrans, "preserve")
        if sourcetxt:
            if isinstance(sourcetxt, str):
                sourcetxt = sourcetxt.decode("utf-8")
            altsource = etree.SubElement(alttrans, self.namespaced("source"))
            altsource.text = sourcetxt
        alttarget = etree.SubElement(alttrans, self.namespaced("target"))
        alttarget.text = txt
        if matchquality:
            alttrans.set("match-quality", matchquality)
        if origin:
            alttrans.set("origin", origin)
        if lang:
            lisa.setXMLlang(alttrans, lang)

    def getalttrans(self, origin=None):
        """Returns <alt-trans> for the given origin as a list of units. No 
        origin means all alternatives."""
        translist = []
        for node in self.xmlelement.iterdescendants(self.namespaced("alt-trans")):
            if self.correctorigin(node, origin):
                # We build some mini units that keep the xmlelement. This 
                # makes it easier to delete it if it is passed back to us.
                newunit = base.TranslationUnit(self.source)

                # the source tag is optional
                sourcenode = node.iterdescendants(self.namespaced("source"))
                try:
                    newunit.source = lisa.getText(sourcenode.next(), getXMLspace(node, self._default_xml_space))
                except StopIteration:
                    pass

                # must have one or more targets
                targetnode = node.iterdescendants(self.namespaced("target"))
                newunit.target = lisa.getText(targetnode.next(), getXMLspace(node, self._default_xml_space))
                #TODO: support multiple targets better
                #TODO: support notes in alt-trans
                newunit.xmlelement = node

                translist.append(newunit)
        return translist

    def delalttrans(self, alternative):
        """Removes the supplied alternative from the list of alt-trans tags"""
        self.xmlelement.remove(alternative.xmlelement)

    def addnote(self, text, origin=None):
        """Add a note specifically in a "note" tag"""
        if isinstance(text, str):
            text = text.decode("utf-8")
        note = etree.SubElement(self.xmlelement, self.namespaced("note"))
        note.text = text.strip()
        if origin:
            note.set("from", origin)

    def getnotelist(self, origin=None):
        """Private method that returns the text from notes matching 'origin' or all notes."""
        notenodes = self.xmlelement.iterdescendants(self.namespaced("note"))
        # TODO: consider using xpath to construct initial_list directly
        # or to simply get the correct text from the outset (just remember to
        # check for duplication.
        initial_list = [lisa.getText(note, getXMLspace(self.xmlelement, self._default_xml_space)) for note in notenodes if self.correctorigin(note, origin)]

        # Remove duplicate entries from list:
        dictset = {}
        notelist = [dictset.setdefault(note, note) for note in initial_list if note not in dictset]

        return notelist

    def getnotes(self, origin=None):
        return '\n'.join(self.getnotelist(origin=origin))

    def removenotes(self, origin="translator"):
        """Remove all the translator notes."""
        notes = self.xmlelement.iterdescendants(self.namespaced("note"))
        for note in notes:
            if self.correctorigin(note, origin=origin):
                self.xmlelement.remove(note)

    def adderror(self, errorname, errortext):
        """Adds an error message to this unit."""
        #TODO: consider factoring out: some duplication between XLIFF and TMX
        text = errorname + ': ' + errortext
        self.addnote(text, origin="pofilter")

    def geterrors(self):
        """Get all error messages."""
        #TODO: consider factoring out: some duplication between XLIFF and TMX
        notelist = self.getnotelist(origin="pofilter")
        errordict = {}
        for note in notelist:
            errorname, errortext = note.split(': ')
            errordict[errorname] = errortext
        return errordict

    def isapproved(self):
        """States whether this unit is approved."""
        return self.xmlelement.get("approved") == "yes"

    def markapproved(self, value=True):
        """Mark this unit as approved."""
        if value:
            self.xmlelement.set("approved", "yes")
        elif self.isapproved():
            self.xmlelement.set("approved", "no")

    def isreview(self):
        """States whether this unit needs to be reviewed"""
        targetnode = self.getlanguageNode(lang=None, index=1)
        return not targetnode is None and \
                "needs-review" in targetnode.get("state", "")

    def markreviewneeded(self, needsreview=True, explanation=None):
        """Marks the unit to indicate whether it needs review. Adds an optional explanation as a note."""
        targetnode = self.getlanguageNode(lang=None, index=1)
        if not targetnode is None:
            if needsreview:
                targetnode.set("state", "needs-review-translation")
                if explanation:
                    self.addnote(explanation, origin="translator")
            else:
                del targetnode.attrib["state"]

    def isfuzzy(self):
#        targetnode = self.getlanguageNode(lang=None, index=1)
#        return not targetnode is None and \
#                (targetnode.get("state-qualifier") == "fuzzy-match" or \
#                targetnode.get("state") == "needs-review-translation")
        return not self.isapproved()

    def markfuzzy(self, value=True):
        if value:
            self.markapproved(False)
        else:
            self.markapproved(True)
        targetnode = self.getlanguageNode(lang=None, index=1)
        if not targetnode is None:
            if value:
                targetnode.set("state", "needs-review-translation")
            else:
                for attribute in ["state", "state-qualifier"]:
                    if attribute in targetnode.attrib:
                        del targetnode.attrib[attribute]

    def settarget(self, text, lang='xx', append=False):
        """Sets the target string to the given value."""
        super(xliffunit, self).settarget(text, lang, append)
        if text:
            self.marktranslated()

# This code is commented while this will almost always return false.
# This way pocount, etc. works well.
#    def istranslated(self):
#        targetnode = self.getlanguageNode(lang=None, index=1)
#        return not targetnode is None and \
#                (targetnode.get("state") == "translated")

    def istranslatable(self):
        value = self.xmlelement.get("translate")
        if value and value.lower() == 'no':
            return False
        return True

    def marktranslated(self):
        targetnode = self.getlanguageNode(lang=None, index=1)
        if targetnode is None:
            return
        if self.isfuzzy() and "state-qualifier" in targetnode.attrib:
            #TODO: consider
            del targetnode.attrib["state-qualifier"]
        targetnode.set("state", "translated")

    def setid(self, id):
        self.xmlelement.set("id", id)

    def getid(self):
        return self.xmlelement.get("id") or ""

    def addlocation(self, location):
        self.setid(location)

    def getlocations(self):
        return [self.getid()]

    def createcontextgroup(self, name, contexts=None, purpose=None):
        """Add the context group to the trans-unit with contexts a list with
        (type, text) tuples describing each context."""
        assert contexts
        group = etree.Element(self.namespaced("context-group"))
        # context-group tags must appear at the start within <group>
        # tags. Otherwise it must be appended to the end of a group
        # of tags.
        if self.xmlelement.tag == self.namespaced("group"):
            self.xmlelement.insert(0, group)
        else:
            self.xmlelement.append(group)
        group.set("name", name)
        if purpose:
            group.set("purpose", purpose)
        for type, text in contexts:
            if isinstance(text, str):
                text = text.decode("utf-8")
            context = etree.SubElement(group, self.namespaced("context"))
            context.text = text
            context.set("context-type", type)

    def getcontextgroups(self, name):
        """Returns the contexts in the context groups with the specified name"""
        groups = []
        grouptags = self.xmlelement.iterdescendants(self.namespaced("context-group"))
        #TODO: conbine name in query
        for group in grouptags:
            if group.get("name") == name:
                contexts = group.iterdescendants(self.namespaced("context"))
                pairs = []
                for context in contexts:
                    pairs.append((context.get("context-type"), lisa.getText(context, getXMLspace(self.xmlelement, self._default_xml_space))))
                groups.append(pairs) #not extend
        return groups

    def getrestype(self):
        """returns the restype attribute in the trans-unit tag"""
        return self.xmlelement.get("restype")

    def merge(self, otherunit, overwrite=False, comments=True, authoritative=False):
        #TODO: consider other attributes like "approved"
        super(xliffunit, self).merge(otherunit, overwrite, comments)
        if self.target:
            self.marktranslated()
            if otherunit.isfuzzy():
                self.markfuzzy()
            elif otherunit.source == self.source:
                self.markfuzzy(False)
        if comments:
            self.addnote(otherunit.getnotes())

    def correctorigin(self, node, origin):
        """Check against node tag's origin (e.g note or alt-trans)"""
        if origin == None:
            return True
        elif origin in node.get("from", ""):
            return True
        elif origin in node.get("origin", ""):
            return True
        else:
            return False

    def multistring_to_rich(self, mstr):
        """Override L{TranslationUnit.multistring_to_rich} which is used by the
            C{rich_source} and C{rich_target} properties."""
        strings = mstr
        if isinstance(mstr, multistring):
            strings = mstr.strings
        elif isinstance(mstr, basestring):
            strings = [mstr]

        return [xml_to_strelem(s) for s in strings]
    multistring_to_rich = classmethod(multistring_to_rich)

    def rich_to_multistring(self, elem_list):
        """Override L{TranslationUnit.rich_to_multistring} which is used by the
            C{rich_source} and C{rich_target} properties."""
        return multistring([unicode(elem) for elem in elem_list])
    rich_to_multistring = classmethod(rich_to_multistring)


class xlifffile(lisa.LISAfile):
    """Class representing a XLIFF file store."""
    UnitClass = xliffunit
    Name = _("XLIFF Translation File")
    Mimetypes  = ["application/x-xliff", "application/x-xliff+xml"]
    Extensions = ["xlf", "xliff"]
    rootNode = "xliff"
    bodyNode = "body"
    XMLskeleton = '''<?xml version="1.0" ?>
<xliff version='1.1' xmlns='urn:oasis:names:tc:xliff:document:1.1'>
<file original='NoName' source-language='en' datatype='plaintext'>
<body>
</body>
</file>
</xliff>'''
    namespace = 'urn:oasis:names:tc:xliff:document:1.1'
    suggestions_in_format = True
    """xliff units have alttrans tags which can be used to store suggestions"""

    def __init__(self, *args, **kwargs):
        self._filename = None
        lisa.LISAfile.__init__(self, *args, **kwargs)
        self._messagenum = 0


    def initbody(self):
        self.namespace = self.document.getroot().nsmap.get(None, None)

        if self._filename:
            self.body = self.getcontextnode(self._filename)
        else:
            self.body = self.document.getroot()

        filenode = self.document.getroot().iterchildren(self.namespaced('file')).next()
        sourcelanguage = filenode.get('source-language')
        if sourcelanguage:
            self.setsourcelanguage(sourcelanguage)
        targetlanguage = filenode.get('target-language')
        if targetlanguage:
            self.settargetlanguage(targetlanguage)

    def addheader(self):
        """Initialise the file header."""
        filenode = self.document.getroot().iterchildren(self.namespaced("file")).next()
        filenode.set("source-language", self.sourcelanguage)
        if self.targetlanguage:
            filenode.set("target-language", self.targetlanguage)

    def createfilenode(self, filename, sourcelanguage=None, targetlanguage=None, datatype='plaintext'):
        """creates a filenode with the given filename. All parameters are needed
        for XLIFF compliance."""
        self.removedefaultfile()
        if sourcelanguage is None:
            sourcelanguage = self.sourcelanguage
        if targetlanguage is None:
            targetlanguage = self.targetlanguage
        filenode = etree.Element(self.namespaced("file"))
        filenode.set("original", filename)
        filenode.set("source-language", sourcelanguage)
        if targetlanguage:
            filenode.set("target-language", targetlanguage)
        filenode.set("datatype", datatype)
        bodyNode = etree.SubElement(filenode, self.namespaced(self.bodyNode))
        return filenode

    def getfilename(self, filenode):
        """returns the name of the given file"""
        return filenode.get("original")

    def setfilename(self, filenode, filename):
        """set the name of the given file"""
        return filenode.set("original", filename)

    def getfilenames(self):
        """returns all filenames in this XLIFF file"""
        filenodes = self.document.getroot().iterchildren(self.namespaced("file"))
        filenames = [self.getfilename(filenode) for filenode in filenodes]
        filenames = filter(None, filenames)
        if len(filenames) == 1 and filenames[0] == '':
            filenames = []
        return filenames

    def getfilenode(self, filename):
        """finds the filenode with the given name"""
        filenodes = self.document.getroot().iterchildren(self.namespaced("file"))
        for filenode in filenodes:
            if self.getfilename(filenode) == filename:
                return filenode
        return None

    def getdatatype(self, filename=None):
        """Returns the datatype of the stored file. If no filename is given,
        the datatype of the first file is given."""
        if filename:
            node = self.getfilenode(filename)
            if not node is None:
                return node.get("datatype")
        else:
            filenames = self.getfilenames()
            if len(filenames) > 0 and filenames[0] != "NoName":
                return self.getdatatype(filenames[0])
        return ""

    def getdate(self, filename=None):
        """Returns the date attribute for the file. If no filename is given,
        the date of the first file is given. If the date attribute is not
        specified, None is returned."""
        if filename:
            node = self.getfilenode(filename)
            if not node is None:
                return node.get("date")
        else:
            filenames = self.getfilenames()
            if len(filenames) > 0 and filenames[0] != "NoName":
                return self.getdate(filenames[0])
        return None

    def removedefaultfile(self):
        """We want to remove the default file-tag as soon as possible if we 
        know if still present and empty."""
        filenodes = list(self.document.getroot().iterchildren(self.namespaced("file")))
        if len(filenodes) > 1:
            for filenode in filenodes:
                if filenode.get("original") == "NoName" and \
                        not list(filenode.iterdescendants(self.namespaced(self.UnitClass.rootNode))):
                    self.document.getroot().remove(filenode)
                break

    def getheadernode(self, filenode, createifmissing=False):
        """finds the header node for the given filenode"""
        # TODO: Deprecated?
        headernode = filenode.iterchildren(self.namespaced("header"))
        try:
            return headernode.next()
        except StopIteration:
            pass
        if not createifmissing:
            return None
        headernode = etree.SubElement(filenode, self.namespaced("header"))
        return headernode

    def getbodynode(self, filenode, createifmissing=False):
        """finds the body node for the given filenode"""
        bodynode = filenode.iterchildren(self.namespaced("body"))
        try:
            return bodynode.next()
        except StopIteration:
            pass
        if not createifmissing:
            return None
        bodynode = etree.SubElement(filenode, self.namespaced("body"))
        return bodynode

    def addsourceunit(self, source, filename="NoName", createifmissing=False):
        """adds the given trans-unit to the last used body node if the filename has changed it uses the slow method instead (will create the nodes required if asked). Returns success"""
        if self._filename != filename:
            if not self.switchfile(filename, createifmissing):
                return None
        unit = super(xlifffile, self).addsourceunit(source)
        self._messagenum += 1
        unit.setid("%d" % self._messagenum)
        return unit

    def switchfile(self, filename, createifmissing=False):
        """adds the given trans-unit (will create the nodes required if asked). Returns success"""
        self._filename = filename
        filenode = self.getfilenode(filename)
        if filenode is None:
            if not createifmissing:
                return False
            filenode = self.createfilenode(filename)
            self.document.getroot().append(filenode)

        self.body = self.getbodynode(filenode, createifmissing=createifmissing)
        if self.body is None:
            return False
        self._messagenum = len(list(self.body.iterdescendants(self.namespaced("trans-unit"))))
        #TODO: was 0 based before - consider
    #    messagenum = len(self.units)
        #TODO: we want to number them consecutively inside a body/file tag
        #instead of globally in the whole XLIFF file, but using len(self.units)
        #will be much faster
        return True

    def creategroup(self, filename="NoName", createifmissing=False, restype=None):
        """adds a group tag into the specified file"""
        if self._filename != filename:
            if not self.switchfile(filename, createifmissing):
                return None
        group = etree.SubElement(self.body, self.namespaced("group"))
        if restype:
            group.set("restype", restype)
        return group

    def __str__(self):
        self.removedefaultfile()
        return super(xlifffile, self).__str__()

    def parsestring(cls, storestring):
        """Parses the string to return the correct file object"""
        xliff = super(xlifffile, cls).parsestring(storestring)
        if xliff.units:
            header = xliff.units[0]
            if ("gettext-domain-header" in (header.getrestype() or "") \
                    or xliff.getdatatype() == "po") \
                    and cls.__name__.lower() != "poxlifffile":
                import poxliff
                xliff = poxliff.PoXliffFile.parsestring(storestring)
        return xliff
    parsestring = classmethod(parsestring)