# -*- coding: utf-8 -*-
# Copyright © 2007 Lateef Alabi-Oki
#
# This file is part of Scribes.
#
# Scribes 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.
#
# Scribes 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 Scribes; if not, write to the Free Software
# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301
# USA

"""
This module documents a class that loads template dictionaries from a
database.

@author: Lateef Alabi-Oki
@organization: The Scribes Project
@copyright: Copyright © 2007 Lateef Alabi-Oki
@license: GNU GPLv2 or Later
@contact: mystilleef@gmail.com
"""

class TemplateLoader(object):
	"""
	This class creates an object that loads templates from a database.
	"""

	def __init__(self, manager, editor):
		"""
		Initialize object.

		@param self: Reference to the TemplateLoader instance.
		@type self: A TemplateLoader object.

		@param manager: Reference to the TemplateManager instance.
		@type manager: A TemplateManager object.

		@param editor: Reference to the text editor.
		@type editor: An Editor object.
		"""
		self.__init_attributes(manager, editor)
		self.__signal_id_1 = manager.connect("destroy", self.__destroy_cb)
		self.__signal_id_2 = editor.connect("loaded-document", self.__loaded_document_cb)
		self.__signal_id_3 = editor.connect("renamed-document", self.__loaded_document_cb)
		# Monitor database for changes.
		from gnomevfs import monitor_add, MONITOR_FILE
		self.__monitor_id = monitor_add(self.__database_uri, MONITOR_FILE,
					self.__database_changed_cb)
		self.__load_templates()

	def __init_attributes(self, manager, editor):
		"""
		Initialize data attributes.

		@param self: Reference to the TemplateLoader instance.
		@type self: A TemplateLoader object.

		@param manager: Reference to the TemplateManager instance.
		@type manager: A TemplateManager object.

		@param editor: Reference to the text editor.
		@type editor: An Editor object.
		"""
		self.__editor = editor
		self.__manager = manager
		# Path to the templates database.
		from SCRIBES.info import metadata_folder
		database_path = metadata_folder + "templates.gdb"
		from gnomevfs import get_uri_from_local_path
		self.__database_uri = get_uri_from_local_path(database_path)
		self.__monitor_id = None
		self.__signal_id_1 = self.__signal_id_2 = self.__signal_id_3 = None
		return

	def __load_general_templates(self):
		"""
		Load generic templates into the text editor.

		This templates are always loaded.

		@param self: Reference to the TemplateLoader instance.
		@type self: A TemplateLoader object.
		"""
		from Metadata import open_template_database, close_template_database
		database = open_template_database()
		general = {}
		for elements in database.keys():
			if elements.startswith("General"):
				general[elements] = database[elements][1]
		self.__manager.emit("loaded-general-templates", general)
		close_template_database(database)
		return

	def __load_language_templates(self):
		"""
		Load language templates into the text editor.

		@param self: Reference to the TemplateLoader instance.
		@type self: A TemplateLoader object.
		"""
		self.__manager.emit("loaded-language-templates", {})
		if self.__editor.uri is None: return
		from SCRIBES.utils import get_language
		language = get_language(self.__editor.uri)
		if not language: return
		language_id = language.get_id()
		from Metadata import open_template_database, close_template_database
		database = open_template_database()
		language = {}
		for elements in database.keys():
			if elements.startswith(language_id):
				language[elements] = database[elements][1]
		self.__manager.emit("loaded-language-templates", language)
		close_template_database(database)
		return

	def __load_templates(self):
		"""
		Load all templates from database.

		@param self: Reference to the TemplateLoader instance.
		@type self: A TemplateLoader object.
		"""
		self.__load_general_templates()
		self.__load_language_templates()
		return

	def __destroy_cb(self, manager):
		"""
		Destroy instance of this object.

		@param self: Reference to the TemplatesManager instance.
		@type self: A TemplatesManager object.

		@param manager: Reference to the TemplatesManager instance.
		@type manager: A TemplatesManager object.
		"""
		from SCRIBES.utils import delete_attributes, disconnect_signal
		if self.__monitor_id:
			from gnomevfs import monitor_cancel
			monitor_cancel(self.__monitor_id)
		disconnect_signal(self.__signal_id_1, manager)
		disconnect_signal(self.__signal_id_2, self.__editor)
		disconnect_signal(self.__signal_id_3, self.__editor)
		delete_attributes(self)
		self = None
		del self
		return

	def __loaded_document_cb(self, editor, uri):
		"""
		Handles callback when the "loaded-document" signal is emitted.

		@param self: Reference to the TemplateLoader instance.
		@type self: A TemplateLoader object.

		@param editor: Reference to the text editor.
		@type editor: An Editor object.
		"""
		self.__load_language_templates()
		return

	def __database_changed_cb(self, monitor_uri, info_uri, event_type):
		"""
		Handles callback when the abbreviation database is modified.

		@param self: Reference to the TemplateLoader instance.
		@type self: An TemplateLoader object.

		@param monitor_uri: The uri that is monitored.
		@type monitor_uri: A String object.

		@param info_uri: The uri that is monitored.
		@type info_uri: A String object.

		@param event_type: The type of modification that occured.
		@type event_type: A gnomevfs.MONITOR_EVENT* object.
		"""
		from gnomevfs import MONITOR_EVENT_DELETED
		from gnomevfs import MONITOR_EVENT_CREATED
		from gnomevfs import MONITOR_EVENT_CHANGED
		from operator import contains
		events = [MONITOR_EVENT_CHANGED, MONITOR_EVENT_DELETED, MONITOR_EVENT_CREATED]
		if contains(events, event_type):
			self.__load_templates()
		return