#

# 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:

#

## 

# @author Teemu Rytkonen

import getpass

import StringIO

import os

import re

import copy

import logging

import httplib

import urllib, urllib2

import simplejson

import posixpath

from cone.public import *

from cone.carbon import persistentjson, model

from cone.storage import authenticate

class WebStorage(api.Storage):

    """

    A general base class for all storage type classes

    @param path : the reference to the root of the storage.

    """

    def __init__(self, path, mode="a", **kwargs):

        api.Storage.__init__(self,path)

        self.mode = mode

        self.extapi = CarbonExtapi(path, **kwargs)

        self.persistentmodule = persistentjson

        # resource cache is a intermediate solution to create a mapping between carbon objects and Configuration project

        self._resource_cache = None

    def _create_resource(self, path, object):

        """

        Create a new resource (configuration|featurelist) to carbon storage.

        """

        # Test the path, whether it is a featurelist or configuration

        try:

            object_type = object.meta.get('type')

        except (TypeError,AttributeError):

            logging.getLogger('cone').error('Cannot dump configuration %s to webstorage without a type.' % path)

            return False

        carbonpath = persistentjson.CarbonResourceMapper().map_confml_resource(object_type, path)

        if object_type == 'featurelist':

            # Create a featurelist 

            success = self.extapi.create_featurelist(carbonpath, object)

            if success:

                self.resource_cache.add_resource_link(path, carbonpath)

            return success

        else:

            # Create a configuration

            success = self.extapi.create_configuration(carbonpath, object)

            if success:

                self.resource_cache.add_resource_link(path, carbonpath)

            return success

    @classmethod

    def supported_storage(cls,path):

        """

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

        E.g. http://foo.com/

        @param path:

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

        """

        if path.startswith('http://'):

            return True

        else:

            return False

    @property

    def resource_cache(self):

        """

        Returns a resource cache dictionary of all the resources inside the Carbon storage. Works as an intermediate 

        solution to link Configuration project concepts to Carbon storage

        """

        if not self._resource_cache: 

            self._resource_cache = ResourceCache()

            reslist = self.extapi.list_resources("/", True)

            # Append all resources to resource cache

            for res in reslist:

                self._resource_cache.add_resource(res)

#                    if isinstance(res, model.ConfigurationResource):

#                        self._resource_cache.add_configuration(res)

#                    elif isinstance(res, model.FeatureListResource):

#                        self._resource_cache.add_featurelist(res)

        return self._resource_cache

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

        """

        find the resources under certain path/path 

        @param path : reference to path where resources are searched

        @param recurse : defines whether to return resources directly under the path or does the listing recurse to subfolders. 

        Default value is False. Set to True to enable recursion.

        @param empty_folders: parameters that defined whether empty folders are included. This parameter is ignored 

        in WebStorage. 

        """

        return self.resource_cache.list_resources(path,recurse)

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

        path = utils.resourceref.remove_begin_slash(path)

        if self.resource_cache.get_resource_object(path):

            return self.resource_cache.get_resource_object(path)

        elif self.resource_cache.get_resource_link(path):

            path = self.resource_cache.get_resource_link(path)

#        path = path.replace(".confml", ".configuration")

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

        try:

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

                strio = self.extapi._get_stringio_from_path(path)

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

                strio = self.extapi._get_stringio_from_path(path)

                strio.seek(0, os.SEEK_END)

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

                strio = StringIO.StringIO()

            else:

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

            res = WebResource(self,path,mode,strio)

            self.__opened__(res)

            return res

        except KeyError:

            raise exceptions.NotResource("The given resource is not found %s" % path)

    def is_resource(self,path):

        return self.resource_cache.is_resource(path)

#        path = path.replace(".confml", ".configuration")

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

#        try:

#            query = urllib.quote(self._get_action_url('is_resource', path))

#            self.conn.request("GET", query)

#            resp = self.conn.getresponse()

#            reader = persistentjson.HasResourceReader()

#            return reader.loads(resp.read())

#        except exceptions.NotFound:

#            return False

    def save_resource(self, res):

        """

        Close resource is no-operation action with webstorage for now

        """

        return 

    def close_resource(self, path):

        """

        Close resource is no-operation action with webstorage

        """

        return 

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

        for path in paths:

            if not self.is_resource(path):

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

                continue

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

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

            wres.write(res.read())

            wres.close()

            res.close()

    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])

        print "unload %s" % path

        if not isinstance(object, api.Configuration):

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

        # Skip the unload storing to storage if the storage is opened in read mode

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

            if self.resource_cache.get_resource_link(path):

                path = self.resource_cache.get_resource_link(path)

            else:

                """ otherwise create the new resource first before update"""

                if self._create_resource(path, object):

                    path = self.resource_cache.get_resource_link(path)

                else:

                    # Creation failed

                    logging.getLogger('cone').error('Creation of %s resource failed' % path)

                    return 

            data = persistentjson.dumps(object)

            self.extapi.update_resource(path, data)

        else:

            raise exceptions.StorageException("Cannot dump object to readonly storage")

        return

    def load(self, path):

        """

        Load resource from a path.

        """

        # Check if the object is already cached or has a cached link to another resource to load

        path = utils.resourceref.remove_begin_slash(path)

        print "load %s" % path

        if self.resource_cache.get_resource_link(path):

            path = self.resource_cache.get_resource_link(path)

        elif self.resource_cache.get_mapped_resource(path):

            path = self.resource_cache.get_mapped_resource(path)

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

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

        else:

            # Add the current path in front of the given path

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

            if not self.is_resource(path):

                raise exceptions.NotResource("No such %s 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)

    def close(self):

        """ No operation in web storage close """

        pass

class WebResource(api.Resource):

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

        api.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 flush(self):

        self.storage.flush_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()

class CarbonExtapi(object):

    ACTIONS = { 'open_resource' : 'get_resource',

                'list_resources' : 'list_resources',

                'is_resource' : 'has_resource',

                'put_resource' : 'put_resource',

                'update_resource' : 'update_resource'   }

    """

    A general container for Carbon extapi action

    """

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

        self.path = path

        self.server_path = ''

        self.service_path = ''

        if path.startswith('http://'):

            path = path.replace('http://','',1)

        pathelems = path.split('/',1)

        self.server_path = pathelems[0]

        if len(pathelems) > 1: 

            self.service_path = pathelems[1]

        self._username = kwargs.get('username', None)

        self._password = kwargs.get('password', None)

        authhandler = authenticate.CarbonAuthHandler()

        authhandler.add_password(self.username, self.password)

        self.conn = urllib2.build_opener(urllib2.HTTPCookieProcessor, authhandler, urllib2.ProxyHandler({}))

    @property

    def username(self):

        if self._username == None:

            self._username = getpass.getuser()

        return self._username 

    @property

    def password(self):

        if self._password == None:

            self._password = getpass.getpass()

        return self._password

    def checklogin(self):

        """

        Checks that we are logged in by loading the main page.

        If we are not logged in it will redirect us to login page.

        """

        loginurl = "http://%(host)s/" % dict(host=self.server_path)

        loginreq = urllib2.Request(loginurl)

        print 'Checking login by opening URL %s ...' % loginurl

        try:

            resp = self.conn.open(loginreq)

        except urllib2.URLError, e:

            print str(e)

            return False

        return True

    def _get_stringio_from_path(self,path):

        """ 

        return a StringIO object containing the data under a given path.

        @return: StringIO buffer

        @raise exception.NotResource: if the resource under path is not found 

        """

        path = utils.resourceref.remove_begin_slash(path)

        action_url = self._get_action_url('open_resource', path)

        req = urllib2.Request(action_url)

        try:

            resp = self.conn.open(req)

            bytes = resp.read()

            strio = StringIO.StringIO(bytes)

            return strio

        except urllib2.HTTPError,e:

            raise exceptions.NotResource("The given path %s could not be retrived from this storage. Server returned status %s." % (path, e))

    def _get_action_url(self, action, path, **kwargs):

        path = utils.resourceref.remove_begin_slash(path)

        return "%s/%s/%s" % (self.path,self.ACTIONS[action], urllib.quote(path))

    def list_resources_for_type(self,path,type, recurse=False):

        """

        find the resources under certain path/path 

        @param path : reference to path where resources are searched

        @param type : resources for particular carbon specific type. 

        @param recurse : defines whether to return resources directly under the path or does the listing recurse to subfolders. 

        Default value is False. Set to True to enable recursion.

        """

        try:

            path = utils.resourceref.join_refs([path,'.'+type])

            path = utils.resourceref.remove_begin_slash(path)

            query = self._get_action_url('list_resources', path)

            req = urllib2.Request(query)

            resp = self.conn.open(req)

            if resp.code == httplib.OK:

                bytes = resp.read()

                reader = persistentjson.ResourceListReader()

                reslist = reader.loads(bytes)

                return reslist

            else:

                return []

        except exceptions.NotFound:

            return []

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

        """

        find the resources under certain path/path 

        @param path : reference to path where resources are searched

        @param recurse : defines whether to return resources directly under the path or does the listing recurse to subfolders. 

        Default value is False. Set to True to enable recursion.

        """

        try:

            path = utils.resourceref.remove_begin_slash(path)

            query = self._get_action_url('list_resources', path)

            req = urllib2.Request(query)

            resp = self.conn.open(req)

            if resp.code == httplib.OK:

                bytes = resp.read()

                reslist = simplejson.loads(bytes)

                return reslist.get('resources',[])

            else:

                return []

        except exceptions.NotFound:

            return []

    def update_resource(self, path, data):

        """

        Update a resource to carbon. The resource can be a CarbonConfiguration or FeatureList object.

        @param object: The object which is dumped to dict with persistentjson and then updated to server. 

        """

        try:

            path = utils.resourceref.remove_begin_slash(path)

            query = self._get_action_url('update_resource', path)

            jsondata = simplejson.dumps(data)

            encdata = urllib.urlencode({'data' : jsondata})

            req = urllib2.Request(query, encdata)

            resp = self.conn.open(req)

            if resp.code == httplib.OK:

                bytes = resp.read()

                respdata = simplejson.loads(bytes)

                success = respdata.get('success') == True

                if success:

                    logging.getLogger('cone').info('Carbon update succeeds to path %s.' % (respdata.get('path')))

                else:

                    logging.getLogger('cone').error('Carbon update %s failed %s' % (path,respdata.get('errors')))

                return success

            else:

                logging.getLogger('cone').error('Carbon update %s failed %s: %s' % (path,resp.code, resp))

                return False

        except urllib2.HTTPError,e:

            utils.log_exception(logging.getLogger('cone'), "HTTPError in %s, %s" % (query,e))

            return False

    def create_feature(self,path, feature, parent=None):

        """

        Create new Carbon feature based on Feature object.

        @param path: The path to the featurelist where the feature is created. 

        @param feature: The feature object 

        @param parent: A possible parent feature ref

        """

        try:

            path = utils.resourceref.remove_begin_slash(path)

            query = self._get_action_url('put_resource', path)

            data = persistentjson.dumps(feature)

            if parent:

                data['parent'] = parent

            jsondata = simplejson.dumps(data)

            encdata = urllib.urlencode({'data' : jsondata})

            req = urllib2.Request(query, encdata)

            resp = self.conn.open(req)

            if resp.code == httplib.OK:

                bytes = resp.read()

                respdata = simplejson.loads(bytes)

                success = respdata.get('success') == True

                if success:

                    logging.getLogger('cone').info('New Carbon feature created to path %s.' % (respdata.get('path')))

                else:

                    logging.getLogger('cone').error('Feature %s creation failed %s' % (feature.fqr,respdata.get('errors')))

                return success

            else:

                logging.getLogger('cone').error('Feature %s creation failed %s: %s' % (feature.fqr,resp.code, resp))

                return False

        except urllib2.HTTPError,e:

            utils.log_exception(logging.getLogger('cone'), "HTTPError in %s, %s" % (query,e))

            return False

    def create_featurelist(self, path, featurelist):

        """

        Create new Carbon featurelist to carbon.

        @param featurelist: The FeatureList object which is created. 

        @return: tuple (success, created_path) where success indicates the success of the operation

        and created_path is the newly created featurelist path on success.

        """

        try:

            path = utils.resourceref.remove_begin_slash(path)

            query = self._get_action_url('put_resource', path)

            data = persistentjson.FeatureListCreateWriter().dumps(featurelist)

            jsondata = simplejson.dumps(data)

            encdata = urllib.urlencode({'data' : jsondata})

            req = urllib2.Request(query, encdata)

            resp = self.conn.open(req)

            if resp.code == httplib.OK:

                bytes = resp.read()

                respdata = simplejson.loads(bytes)

                success = respdata.get('success') == True

                newpath = respdata.get('path')

                if success:

                    logging.getLogger('cone').info('New Carbon featurelist created to path %s.' % (newpath))

                else:

                    logging.getLogger('cone').error('FeatureList %s creation failed %s' % (featurelist.path,respdata.get('errors')))

                return (success, newpath)

            else:

                logging.getLogger('cone').error('FeatureList %s creation failed %s: %s' % (featurelist.path,resp.code, resp))

                return (False,'')

        except urllib2.HTTPError,e:

            utils.log_exception(logging.getLogger('cone'), "HTTPError in %s, %s" % (query,e))

            return (False,'')

    def create_configuration(self, path, configuration):

        """

        Create new Carbon configuration to carbon.

        @param path: The path to the configuration 

        @param configuration: The CarbonConfiguration object

        @return: tuple (success, created_path) where success indicates the success of the operation

        and created_path is the newly created configuration path on success.

        """

        try:

            path = utils.resourceref.remove_begin_slash(path)

            query = self._get_action_url('put_resource', path)

            data = persistentjson.ConfigurationCreateWriter().dumps(configuration)

            jsondata = simplejson.dumps(data)

            encdata = urllib.urlencode({'data' : jsondata})

            req = urllib2.Request(query, encdata)

            resp = self.conn.open(req)

            if resp.code == httplib.OK:

                bytes = resp.read()

                respdata = simplejson.loads(bytes)

                success = respdata.get('success') == True

                newpath = respdata.get('path')

                if success:

                    logging.getLogger('cone').info('New Carbon configuration created to path %s.' % (newpath))

                else:

                    logging.getLogger('cone').error('CarbonConfiguration %s creation failed %s' % (configuration.path,respdata.get('errors')))

                return (success, newpath)

            else:

                logging.getLogger('cone').error('CarbonConfiguration %s creation failed %s: %s' % (configuration.path,resp.code, resp))

                return (False,'')

        except urllib2.HTTPError,e:

            utils.log_exception(logging.getLogger('cone'), "HTTPError in %s, %s" % (query,e))

            return (False,'')