#

# 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:

#

from cone.public import exceptions, plugin

import crml_impl

from crml_model import *

def get_required_attr(elem, attrname):

    """

    Get a required attribute from an XML element or raise an exception.

    """

    attr = elem.get(attrname)

    if attr is None:

        raise exceptions.ParseError("<%s> element does not have the required '%s' attribute!" % (elem.tag, attrname))

    return attr

def convert_num(string):

    """

    Convert the given string into a number.

    - The number can be in decimal or hexadecimal format.

    - If None is passed, None is also returned.

    """

    if string in ('', None):

        return None

    try:

        return long(string)

    except ValueError:

        return long(string, 16)

class CrmlReader(plugin.ReaderBase):

    NAMESPACE = 'http://www.s60.com/xml/cenrep/1'

    FILE_EXTENSIONS = ['crml']

    @classmethod

    def read_impl(cls, resource_ref, configuration, etree):

        reader = CrmlReader()

        repository = reader.read_repository(etree)

        return crml_impl.CrmlImpl(resource_ref, configuration, repository)

    def read_repository(self, elem):

        """

        Read a CrmlRepository object from the given XML element.

        """

        # Read repository attributes

        repo = CrmlRepository(

            uid_value = elem.get('uidValue'),

            uid_name  = elem.get('uidName'),

            owner     = elem.get('owner'),

            version   = elem.get('initialisationFileVersion', '1'),

            access    = self.read_access(elem))

        if elem.get('backup') == 'true':    repo.backup = True

        if elem.get('rfs') == 'true':       repo.rfs = True

        # Read all keys

        for sub_elem in elem:

            key_obj = self.read_key(sub_elem)

            if key_obj is not None:

                # Read-only keys have always cap_wr=AlwaysFail.

                # the isinstance() check is for CT2 output compatibility

                if not isinstance(key_obj, CrmlKeyRange):

                    if key_obj.read_only:

                        key_obj.access.cap_wr = 'AlwaysFail'

                        key_obj.access.sid_wr = None

                repo.keys.append(key_obj)

        if repo.access == CrmlAccess(cap_rd='AlwaysPass') and len(repo.keys) == 0:

            repo.access.cap_rd = None

        return repo

    def read_access(self, elem):

        """

        Read a CrmlAccess object from the given XML element.

        @param elem: The element from which to parse an access definition. Should be any

            element that can contain an access definition (i.e. 'repository', 'key', or 'keyRange').

        """

        access = CrmlAccess()

        read_cap_found = False

        write_cap_found = False

        for access_elem in elem.findall('{%s}access' % self.NAMESPACE):

            type = access_elem.get('type')

            if type == 'R' and not read_cap_found:

                access.cap_rd = access_elem.get('capabilities')

                access.sid_rd = access_elem.get('sid')

                read_cap_found = True

            elif type == 'W' and not write_cap_found:

                access.cap_wr = access_elem.get('capabilities')

                access.sid_wr = access_elem.get('sid')

                write_cap_found = True

        return access

    def read_common_key_attrs(self, key_elem, key_obj):

        """

        Read common attributes into an object of class CrmlKeyBase from an XML element.

        """

        if not isinstance(key_obj, CrmlKeyBase):

            raise ValueError("Expected object of type %s" % CrmlKeyBase.__name__)

        if key_elem.get('readOnly') == 'true':  key_obj.read_only = True

        if key_elem.get('backup') == 'true':    key_obj.backup = True

        key_obj.access = self.read_access(key_elem)

        key_obj.name = key_elem.get('name')

    def read_key(self, key_elem):

        key_obj = None

        if key_elem.tag == '{%s}key' % self.NAMESPACE:

            # Determine whether the key is a normal key or a bitmask key

            # based on the presence of <bit> elements

            tags = [e.tag for e in key_elem]

            if '{%s}bit' % self.NAMESPACE in tags:

                key_obj = self.read_bitmask_key(key_elem)

            else:

                key_obj = self.read_simple_key(key_elem)

        elif key_elem.tag == '{%s}keyRange' % self.NAMESPACE:

            key_obj = self.read_key_range(key_elem)

        return key_obj

    def read_simple_key(self, key_elem):

        """

        Read a CrmlSimpleKey object from the given XML element.

        """

        expected_tag = '{%s}key' % self.NAMESPACE

        if key_elem.tag != expected_tag:

            raise RuntimeError("Incorrect XML element passed to read_simple_key(): %s, expected %s" % (key_elem.tag, expected_tag))

        key = CrmlSimpleKey(

            ref  = get_required_attr(key_elem, 'ref').replace('/', '.'),

            int  = get_required_attr(key_elem, 'int'),

            type = key_elem.get('type', 'int'))

        self.read_common_key_attrs(key_elem, key)

        return key

    def read_bitmask_key(self, key_elem):

        """

        Read a CrmlBitmaskKey object from the given XML element.

        """

        expected_tag = '{%s}key' % self.NAMESPACE

        if key_elem.tag != expected_tag:

            raise RuntimeError("Incorrect XML element passed to read_bitmask_key(): %s, expected %s" % (key_elem.tag, expected_tag))

        # Read attributes

        key = CrmlBitmaskKey(

            int  = get_required_attr(key_elem, 'int'),

            type = key_elem.get('type', 'int'))

        self.read_common_key_attrs(key_elem, key)

        # Read bits

        for bit_elem in key_elem.findall('{%s}bit' % self.NAMESPACE):

            ref = get_required_attr(bit_elem, 'ref').replace('/', '.')

            if bit_elem.get('value') == 'false':    invert = True

            else:                                   invert = False

            index = int(bit_elem.text.strip())

            key.bits.append(CrmlBit(ref=ref, index=index, type=type, invert=invert))

        return key

    def read_key_range(self, key_range_elem):

        """

        Read a CrmlKeyRange object from the given XML element.

        """

        expected_tag = '{%s}keyRange' % self.NAMESPACE

        if key_range_elem.tag != expected_tag:

            raise RuntimeError("Incorrect XML element passed to read_key_range(): %s, expected %s" % (key_range_elem.tag, expected_tag))

        # Read attributes

        ref = key_range_elem.get('ref')

        if ref is not None: ref = ref.replace('/', '.')

        key_range = CrmlKeyRange(

            ref         = ref,

            first_int   = get_required_attr(key_range_elem, "firstInt"),

            last_int    = get_required_attr(key_range_elem, "lastInt"),

            count_int   = key_range_elem.get('countInt'),

            first_index = convert_num(key_range_elem.get('firstIndex', '0')),

            index_bits  = convert_num(key_range_elem.get('indexBits')))

        self.read_common_key_attrs(key_range_elem, key_range)

        # Read sub-keys

        for subkey_elem in key_range_elem.findall('{%s}key' % self.NAMESPACE):

            ref = get_required_attr(subkey_elem, 'ref').replace('/', '.')

            int = get_required_attr(subkey_elem, 'int')

            name = subkey_elem.get('name')

            type = subkey_elem.get('type', 'int')

            key_range.subkeys.append(CrmlKeyRangeSubKey(ref=ref, int=int, name=name, type=type))

        return key_range