# -*- python -*-
# -*- coding: utf-8 -*-
#
# Gramps - a GTK+/GNOME based genealogy program
#
# Copyright (C) 2000-2005  Donald N. Allingham
# Copyright (C) 2011       Tim G L Lyons
#
# 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
#

# $Id$

"""
   This module provides management of all the drag and drop target information
   required by gramps widgets.

   Adding a new drag and drop target.
   ==================================

   To add a new target: add a new _DdType to in _DdTargets.__init__ and
   then add this new type to the list returned from either all_text_types()
   and all_text_targets() or  or all_gramps_targets() and all_gramps_types().

   Usage
   =====

   The module defines a singleton instance of _DdTargets called DdTargets.

   from DdTargets import DdTargets

   drag_dest_set(gtk.DEST_DEFAULT_ALL,
                 DdTargets.all_targets(),
                 ACTION_COPY)
   
"""

#-------------------------------------------------------------------------
#
# set up logging
#
#-------------------------------------------------------------------------
import logging
log = logging.getLogger(".DdTargets")


class _DdType:
    """Represents the fields needed by a drag and drop target."""
    
    _APP_ID_OFFSET = 40  # Starting value of app_ids
    
    def __init__(self, container, drag_type, target_flags=0, app_id=None):
        """Create a new DdType:

        drag_type: string holding the name of the type.
        target_flags: int value that will be passed to drop target.
        app_id: integer target id passed to drop target.
        """
        
        self.drag_type = drag_type
        self.target_flags = target_flags
        self.app_id = app_id or self._calculate_id()
        container.insert(self)

    def _calculate_id(self):
        """Return the next available app_id."""
        
        idval = _DdType._APP_ID_OFFSET
        _DdType._APP_ID_OFFSET += 1
        return idval

    def target(self):
        """
        Return the full target information in the format required by the 
        Gtk functions.
        
        """
        return (self.drag_type, self.target_flags, self.app_id)
        
        

class _DdTargets(object):
    """A single class that manages all the drag and drop targets."""
    
    _instance = None # Singleton instance

    def __new__(cls):
        """Ensure that we never have more than one instance."""
        
        if _DdTargets._instance:
            return _DdTargets._instance
        _DdTargets._instance = object.__new__(cls)
        return _DdTargets._instance        

    def __init__(self):
        """Set up the drag and drop targets."""
        
        self._type_map = {}
        self._app_id_map = {}
        
        self.ADDRESS            = _DdType(self, 'paddr')
        self.ATTRIBUTE          = _DdType(self, 'pattr')
        self.CHILDREF           = _DdType(self, 'childref')
        self.DATA               = _DdType(self, 'data_tuple')
        self.EVENT              = _DdType(self, 'pevent')
        self.EVENTREF           = _DdType(self, 'eventref')
        self.FAMILY_ATTRIBUTE   = _DdType(self, 'fattr')
        self.FAMILY_EVENT       = _DdType(self, 'fevent')
        self.LOCATION           = _DdType(self, 'location')
        self.MEDIAOBJ           = _DdType(self, 'mediaobj')
        self.MEDIAREF           = _DdType(self, 'mediaref')
        self.NAME               = _DdType(self, 'name')
        self.NOTE_LINK          = _DdType(self, 'note-link')
        self.PLACE_LINK         = _DdType(self, 'place-link')
        self.REPO_LINK          = _DdType(self, 'repo-link')
        self.REPOREF            = _DdType(self, 'reporef')
        self.PERSON_LINK        = _DdType(self, 'person-link')
        self.FAMILY_LINK        = _DdType(self, 'family-link')
        self.LINK_LIST          = _DdType(self, 'link-list')
        self.RAW_LIST           = _DdType(self, 'raw-list')
        self.HANDLE_LIST        = _DdType(self, 'handle-list')
        self.PERSONREF          = _DdType(self, 'personref')
        self.SOURCEREF          = _DdType(self, 'srcref')
        self.SOURCE_LINK        = _DdType(self, 'source-link')
        self.URL                = _DdType(self, 'url')
        self.SURNAME            = _DdType(self, 'surname')
        self.CITATION_LINK      = _DdType(self, 'citation-link')

        # List of all types that are used between
        # gramps widgets but should not be exported
        # to non gramps widgets.
        self._all_gramps_types = [
            self.ADDRESS, 
            self.ATTRIBUTE, 
            self.CHILDREF, 
            self.EVENT, 
            self.EVENTREF, 
            self.LOCATION, 
            self.MEDIAOBJ, 
            self.MEDIAREF, 
            self.NAME, 
            self.NOTE_LINK, 
            self.PLACE_LINK, 
            self.PERSON_LINK, 
            self.FAMILY_LINK, 
            self.LINK_LIST, 
            self.RAW_LIST, 
            self.HANDLE_LIST, 
            self.PERSONREF, 
            self.REPO_LINK, 
            self.REPOREF, 
            self.SOURCEREF, 
            self.SOURCE_LINK, 
            self.URL, 
            self.SURNAME,
            self.CITATION_LINK
        ]
        
        self.CHILD         = _DdType(self, 'child')
        self.SPOUSE        = _DdType(self, 'spouse')
        self.TEXT_MIME     = _DdType(self, 'text/plain', 0, 0)
        self.TEXT          = _DdType(self, 'TEXT', 0, 1)
        self.STRING        = _DdType(self, 'STRING', 0, 2)
        self.COMPOUND_TEXT = _DdType(self, 'COMPOUND_TEXT', 0, 3)
        self.UTF8_STRING   = _DdType(self, 'UTF8_STRING', 0, 4)
        self.URI_LIST      = _DdType(self, 'text/uri-list', 0, 5)
        self.APP_ROOT      = _DdType(self, 'application/x-rootwin-drop', 0, 6)

        # List of all the text types. These are types
        # that can be interpreted as text.
        self._all_text_types = (self.UTF8_STRING, 
                                self.TEXT, 
                                self.TEXT_MIME, 
                                self.STRING, 
                                self.COMPOUND_TEXT)

    def insert(self, dd_type):
        """
        Add a target to the lookup lists. These lists are
        used purely for performance reasons.
        """
        
        self._type_map[dd_type.drag_type] = dd_type
        self._app_id_map[dd_type.app_id] = dd_type

    def get_dd_type_from_type_name(self, type_name):
        return self._type_map.get(type_name, None)

    def get_dd_type_from_app_id(self, app_id):
        return self._app_id_map.get(app_id, None)

    def is_text_type(self, type_name):
        return type_name in self.all_text_types()

    def all_text(self):
        return self._all_text_types
        
    def all_text_types(self):
        """
        Return a list of all the type names that could be
        used as the type of a string.
        """
        
        return tuple([t.drag_type for t in self._all_text_types])
    
    def is_gramps_type(self, type_name):
        return type_name in self.all_gramps_types()

    def all_gramps_types(self):
        """Return a list of all the type names that are internal to gramps."""

        return tuple([t.drag_type for t in self._all_gramps_types])

    def all_text_targets(self):
        """Return a list of all the targets that could be used for text."""
        
        return tuple([t.target() for t in self._all_text_types])


    def all_gramps_targets(self):
        """Return a list off the internal gramps targets."""

        return tuple([t.target() for t in self._all_gramps_types])

    def all_targets(self):
        """Return a list of all the known targets."""
        return self.all_gramps_targets() + self.all_text_targets()

# Create the singleton instance.

DdTargets = _DdTargets()


#
# Below here is test code.
#
if __name__ == "__main__":

    print repr(DdTargets.all_text_types())
    print repr(DdTargets.URL)
    print DdTargets.is_gramps_type('pevent')
