#

# Copyright (c) 2009 Nokia Corporation and/or its subsidiary(-ies).

# All rights reserved.

# This component and the accompanying materials are made available

# under the terms of "Eclipse Public License v1.0"

# which accompanies this distribution, and is available

# at the URL "http://www.eclipse.org/legal/epl-v10.html".

#

# Initial Contributors:

# Nokia Corporation - initial contribution.

#

# Contributors:

#

# Description: 

#

import zipfile,zlib, StringIO, os, logging

import datetime

import tempfile

try:

    from cElementTree import ElementTree

except ImportError:

    try:    

        from elementtree import ElementTree

    except ImportError:

        try:

            from xml.etree import cElementTree as ElementTree

        except ImportError:

            from xml.etree import ElementTree

from cone.public import api, utils, persistence, exceptions

from cone.public.api import Resource, Storage, Configuration, Folder

from cone.storage import metadata, common

from cone.confml import persistentconfml

class ZipException(exceptions.StorageException):

    def __init__(self,value):

        self.value = value

    def __str__(self):

        return repr(self.value)  

class ZipStorage(common.StorageBase):

    """

    A storage for zip file 

    """

    TEMP_FILE = '_temp_%i.zip' % os.getpid()

    def __init__(self, path ,mode, **kwargs):

        """

        Open the given filename object as a cpf zipfile

        """

        self.mode        = mode

        self.persistentmodule = persistentconfml

        self.compression = zipfile.ZIP_DEFLATED

        self.modified = False

        self.logger = logging.getLogger('cone')

        self.logger.debug("ZipStorage path %s open in mode %s" % (path,self.mode))

        try:

            # If opening the file in read/append mode check that the given file is a zipfile

            if self.get_mode(mode) != self.MODE_WRITE:

                if os.path.exists(path) and not zipfile.is_zipfile(path):

                    raise ZipException("The file %s is not a zip file!" % path) 

            self.zipfile = zipfile.ZipFile(path,self.mode,self.compression)

        except IOError,e:

            raise ZipException("ZipFile open error: %s" % e)

        super(ZipStorage, self).__init__(path)

    def _zippath(self, path):

        """

        Convert a norm path to zipfile path  

        """

        normpath = utils.resourceref.norm(path)

        return normpath.lstrip('.')

    @classmethod

    def supported_storage(cls,path):

        """

        Class method for determing if the given clas supports a storage by given path. 

        E.g. foo.zip, foo.cpd, foo/bar, http://foo.com/

        @param path:

        @return: Boolean value. True if the storage of the path is supported. False if not.  

        """

        if utils.resourceref.get_ext(path) == "zip" or \

           utils.resourceref.get_ext(path) == "cpf":

            return True

        else:

            return False

    def open_resource(self,path,mode="r"):

        strio = None

        path = utils.resourceref.remove_begin_slash(path)

        fullpath = utils.resourceref.join_refs([self.get_current_path(),path])

        try:

            if self.get_mode(mode) == self.MODE_READ:

                if not self.is_resource(fullpath):

                    raise exceptions.NotResource("Resource is not found %s" % fullpath)

                bytes = self.zipfile.read(fullpath)

                strio = StringIO.StringIO(bytes)    

            elif self.get_mode(mode) == self.MODE_APPEND:

                if not self.is_resource(fullpath):

                    raise exceptions.NotResource("Resource is not found %s" % fullpath)

                bytes = self.zipfile.read(fullpath)

                # delete the "old" resource

                self.delete_resource(fullpath)

                strio = StringIO.StringIO(bytes)

                strio.seek(0, os.SEEK_END)

            elif self.get_mode(mode) == self.MODE_WRITE:

                if self.is_resource(fullpath):

                    # delete the "old" resource

                    self.delete_resource(fullpath)

                # Create a new string buffer because the resource is overwritten

                strio = StringIO.StringIO()

            else:

                raise ZipException("Unrecognized mode %s" % mode)

            res = ZipFileResource(self,fullpath,mode,strio)

            self.__opened__(res)

            return res

        except KeyError:

            raise exceptions.NotResource(path)

    def is_resource(self,path):

        path = utils.resourceref.remove_begin_slash(path)

        files = self.zipfile.namelist()

        try:

            i = files.index(path)

            return True

        except ValueError:

            return False

    def is_dir(self,path):

        """

        Get an array of files in a folder

        """

        try:

            zinfo = self.zipfile.getinfo(utils.resourceref.add_end_slash(path))

            return True

        except KeyError:

            return False 

    def list_resources(self,path,recurse=False, empty_folders=False): 

        """

        Get an array of files in a folder  

        """

        path = utils.resourceref.remove_begin_slash(path)

        fullpath = utils.resourceref.join_refs([self.get_current_path(),path])

        fullpath = self._zippath(fullpath)

        retarray = []

        filelist = self.zipfile.namelist()

        for name in filelist:

            (filepath,filename) = os.path.split(name)

            curname = utils.resourceref.replace_dir(name, self.get_current_path(),'')

            # return directories only if specified

            if empty_folders == True or not self.is_dir(name):

                # Skip the filename if it is marked as deleted

                if self.__has_open__(name) and self.__get_open__(name)[-1].get_mode() == api.Storage.MODE_DELETE:

                    continue

                if filepath == fullpath:

                    retarray.append(curname)

                elif recurse and filepath.startswith(fullpath):

                    retarray.append(curname)

        #retarray = sorted(utils.distinct_array(retarray))

        return retarray

    def import_resources(self,paths,storage,empty_folders=False):

        for path in paths:

            if not storage.is_resource(path) and empty_folders==False:

                logging.getLogger('cone').warning("The given path is not a Resource in the storage %s! Ignoring from export!" % path)

                continue

            if storage.is_resource(path):

                wres = self.open_resource(path,'wb')

                res  = storage.open_resource(path,"rb")

                wres.write(res.read())

                wres.close()

                res.close()

            elif storage.is_folder(path) and empty_folders:

                self.create_folder(path)

    def export_resources(self,paths,storage,empty_folders=False):

        for path in paths:

            if not self.is_resource(path) and empty_folders==False:

                logging.getLogger('cone').warning("The given path is not a Resource in this storage %s! Ignoring from export!" % path)

                continue

            if  self.is_resource(path):

                wres = storage.open_resource(path,'wb')

                res  = self.open_resource(path,"rb")

                wres.write(res.read())

                wres.close()

                res.close()

            if  self.is_folder(path) and  empty_folders:

                storage.create_folder(path)

    def close_resource(self, res):

        """

        Close the given resource instance. Normally this is called by the Resource object 

        in its own close.

        @param res: the resource object to close. 

        """

        try:

            self.__closed__(res)

            if self.get_mode(self.mode) != api.Storage.MODE_READ and \

               (res.get_mode() == api.Storage.MODE_WRITE or res.get_mode() == api.Storage.MODE_APPEND):

                self.zipfile.writestr(res.path,res.getvalue())

        except KeyError,e:

            raise exceptions.StorageException("No such %s open resource! %s" % (res.path,e))

    def save_resource(self, res):

        """

        Flush the changes of a given resource instance. Normally this is called by the Resource object 

        in its own save.

        @param res: the resource to the resource to save. 

        """

        if not self.__has_resource__(res):

            raise exceptions.NotResource("No such %s open resource!" % res.path)

        else:

            self.zipfile.writestr(res.path,res.getvalue())

    def delete_resource(self,path):

        """

        Delete the given resource from storage

        @param res : Resource object to the resource 

        raises a NotSupportedException exception if delete operation is not supported by the storage

        """

        # First close all open resources

        for res in self.__get_open__(path):

            self.__closed__(res)

        self.modified = True 

        self.zipfile.filelist.remove(self.zipfile.NameToInfo[path])

        del self.zipfile.NameToInfo[path]

    def create_folder(self,path):

        """

        Create a folder entry to a path

        @param path : path to the folder

        """

        fullpath = utils.resourceref.join_refs([self.get_current_path(),path])

        fullpath = utils.resourceref.add_end_slash(self._zippath(fullpath))

        if self.is_folder(fullpath):

            # delete the "old" resource

            self.delete_resource(fullpath)

        now = datetime.datetime.now()

        zinfo = zipfile.ZipInfo(fullpath,

                                (now.year,now.month, now.day, 

                                 now.hour, now.minute, now.second)

                                )

        # set an external attribute for directory entry

        zinfo.external_attr = 0x10

        zinfo.extract_version = 10

        self.zipfile.writestr(zinfo,'') 

    def delete_folder(self,path):

        """

        Delete a folder entry from a path. The path must be empty.

        @param path : path to the folder

        """

        pass

    def is_folder(self,path):

        """

        Check if the given path is an existing folder in the storage

        @param path : path to the folder

        """

        fullpath = utils.resourceref.join_refs([self.get_current_path(),path])

        folderpath = self._zippath(fullpath)

        return self.is_dir(folderpath)

    def close(self):

        if self.zipfile:

            super(ZipStorage,self).close()

            self.zipfile.close()

            # Recreate the zip file if the zip has been modified to make a zip without 

            # duplicate local file entries

            if self.modified:

                oldfile = None

                newzipfile = None

                tmp_path = os.path.join(tempfile.gettempdir(), self.TEMP_FILE)

                os.rename(self.path, tmp_path)

                oldfile = zipfile.ZipFile(tmp_path,"r")

                newzipfile = zipfile.ZipFile(self.path,"w",self.compression)

                for fileinfo in oldfile.infolist():

                    newzipfile.writestr(fileinfo, oldfile.read(fileinfo.filename))

                if oldfile: oldfile.close()

                if newzipfile: newzipfile.close()

                os.unlink(tmp_path)

            self.zipfile = None

        else:

            raise exceptions.StorageException('Storage %s has been already closed!' % self.path)

    def unload(self, path, object):

        """

        Dump a given object to the storage (reference is fetched from the object)

        @param object: The object to dump to the storage, which is expected to be an instance 

        of Base class.

        """

        # Add the current path in front of the given path

        path = utils.resourceref.join_refs([self.get_current_path(), path])

        if not isinstance(object, api.Configuration):

            raise exceptions.StorageException("Cannot dump object type %s" % object.__class__)

        if self.get_mode(self.mode) != api.Storage.MODE_READ:

            res = self.open_resource(path,"wb")

            data = "%s" % self.persistentmodule.dumps(object)

            res.write(data)

            res.close()

        return

    def load(self, path):

        """

        Load an from a reference.

        """

        # Add the current path in front of the given path

        path = utils.resourceref.join_refs([self.get_current_path(), path])

        if not utils.resourceref.get_ext(path) == "confml":

            raise exceptions.StorageException("Cannot load reference type %s" % utils.resourceref.get_ext(path))

        if self.is_resource(path):

            res = self.open_resource(path,"r")

            # read the resource with persistentmodule

            try:

                obj = self.persistentmodule.loads(res.read())

                obj.set_path(path)

                res.close()

                return obj

            except exceptions.ParseError,e:

                logging.getLogger('cone').error("Resource %s parsing failed with exception: %s" % (path,e))

                # returning an empty config in case of xml parsing failure.

                return api.Configuration(path)

        else:

            raise exceptions.NotResource("No such %s resource!" % path)

class ZipFileResource(Resource):

    def __init__(self,storage,path,mode,handle):

        Resource.__init__(self,storage,path,mode)

        self.handle = handle

    def read(self,bytes=0):

        if bytes == 0:

            return self.handle.read()

        else:

            return self.handle.read(bytes)

    def write(self,string):

        if self.get_mode() == api.Storage.MODE_READ:

            raise exceptions.StorageException("Writing attempted to %s in read-only mode." % self.path)

        else:

            self.handle.write(string)

    def truncate(self,size=0):

        raise exceptions.NotSupportedException()

    def save(self):

        self.storage.save_resource(self)

    def close(self):

        self.storage.close_resource(self)

        self.handle.close()

    def get_size(self):

        if self.get_mode() == api.Storage.MODE_WRITE:

            raise exceptions.StorageException("Reading resource size attempted to %s in write-only mode." % self.path)

        return len(self.handle.getvalue())

    def getvalue(self):

        return self.handle.getvalue()

    def get_content_info(self):

        if self.content_info == None:

            self.content_info = utils.make_content_info(self, self.handle.getvalue())

        return self.content_info