#
# Gramps - a GTK+/GNOME based genealogy program
#
# Copyright (C) 2000-2006  Donald N. Allingham
# Copyright (C) 2010       Michiel D. Nauta
#
# 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
#

# $Id$

"""
MediaBase class for GRAMPS.
"""

#-------------------------------------------------------------------------
#
# GRAMPS modules
#
#-------------------------------------------------------------------------
from .mediaref import MediaRef
from .const import IDENTICAL, EQUAL, DIFFERENT

#-------------------------------------------------------------------------
#
# MediaBase class
#
#-------------------------------------------------------------------------
class MediaBase(object):
    """
    Base class for storing media references.
    """
    
    def __init__(self, source=None):
        """
        Create a new MediaBase, copying from source if not None.
        
        :param source: Object used to initialize the new object
        :type source: MediaBase
        """
        self.media_list = list(map(MediaRef, source.media_list)) if source else []

    def serialize(self):
        """
        Convert the object to a serialized tuple of data.
        """
        return [mref.serialize() for mref in self.media_list]

    def to_struct(self):
        """
        Convert the data held in this object to a structure (eg,
        struct) that represents all the data elements.
        
        This method is used to recursively convert the object into a
        self-documenting form that can easily be used for various
        purposes, including diffs and queries.

        These structures may be primitive Python types (string,
        integer, boolean, etc.) or complex Python types (lists,
        tuples, or dicts). If the return type is a dict, then the keys
        of the dict match the fieldname of the object. If the return
        struct (or value of a dict key) is a list, then it is a list
        of structs. Otherwise, the struct is just the value of the
        attribute.

        :returns: Returns a struct containing the data of the object.
        :rtype: list
        """
        return [mref.to_struct() for mref in self.media_list]

    def unserialize(self, data):
        """
        Convert a serialized tuple of data to an object.
        """
        self.media_list = [MediaRef().unserialize(item) for item in data]
        return self

    def add_media_reference(self, media_ref):
        """
        Add a :class:`~gen.lib.mediaref.MediaRef` instance to the object's media list.

        :param media_ref: :class:`~gen.lib.mediaref.MediaRef` instance to be added to the object's
            media list.
        :type media_ref: :class:`~gen.lib.mediaref.MediaRef`
        """
        self.media_list.append(media_ref)

    def get_media_list(self):
        """
        Return the list of :class:`~gen.lib.mediaref.MediaRef` instances associated with the object.

        :returns: list of :class:`~gen.lib.mediaref.MediaRef` instances associated with the object
        :rtype: list
        """
        return self.media_list

    def set_media_list(self, media_ref_list):
        """
        Set the list of :class:`~gen.lib.mediaref.MediaRef` instances associated with the object.
        It replaces the previous list.

        :param media_ref_list: list of :class:`~gen.lib.mediaref.MediaRef` instances to be assigned
            to the object.
        :type media_ref_list: list
        """
        self.media_list = media_ref_list

    def _merge_media_list(self, acquisition):
        """
        Merge the list of media references from acquisition with our own.

        :param acquisition: the media list of this object will be merged with
            the current media reference list.
        :rtype acquisition: MediaBase
        """
        media_list = self.media_list[:]
        for addendum in acquisition.get_media_list():
            for obj in media_list:
                equi = obj.is_equivalent(addendum)
                if equi == IDENTICAL:
                    break
                elif equi == EQUAL:
                    obj.merge(addendum)
                    break
            else:
                self.media_list.append(addendum)

    def has_media_reference(self, obj_handle) :
        """
        Return True if the object or any of it's child objects has reference
        to this media object handle.

        :param obj_handle: The media handle to be checked.
        :type obj_handle: str
        :returns: Returns whether the object or any of it's child objects has 
                reference to this media handle.
        :rtype: bool
        """
        return obj_handle in [media_ref.ref for media_ref in self.media_list]

    def remove_media_references(self, obj_handle_list):
        """
        Remove references to all media handles in the list.

        :param obj_handle_list: The list of media handles to be removed.
        :type obj_handle_list: list
        """
        new_media_list = [media_ref for media_ref in self.media_list
                            if media_ref.ref not in obj_handle_list]
        self.media_list = new_media_list

    def replace_media_references(self, old_handle, new_handle):
        """
        Replace all references to old media handle with the new handle and
        merge equivalent entries.

        :param old_handle: The media handle to be replaced.
        :type old_handle: str
        :param new_handle: The media handle to replace the old one with.
        :type new_handle: str
        """
        refs_list = [ media_ref.ref for media_ref in self.media_list ]
        new_ref = None
        if new_handle in refs_list:
            new_ref = self.media_list[refs_list.index(new_handle)]
        n_replace = refs_list.count(old_handle)
        for ix_replace in range(n_replace):
            idx = refs_list.index(old_handle)
            self.media_list[idx].ref = new_handle
            refs_list[idx] = new_handle
            if new_ref:
                media_ref = self.media_list[idx]
                equi = new_ref.is_equivalent(media_ref)
                if equi != DIFFERENT:
                    if equi == EQUAL:
                        new_ref.merge(media_ref)
                    self.media_list.pop(idx)
                    refs_list.pop(idx)
