/*	
 * Copyright (C) 2013 - Juan Ferrer Toribio
 *
 * 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 3 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, see <http://www.gnu.org/licenses/>.
 */

#include "vn-column-combo.h"
#include "../vn-list-model.h"

static void vn_column_combo_model_holder_init (DbModelHolderInterface * iface);

G_DEFINE_TYPE_WITH_CODE (VnColumnCombo, vn_column_combo, VN_TYPE_COLUMN,
	G_IMPLEMENT_INTERFACE (DB_TYPE_MODEL_HOLDER,
		vn_column_combo_model_holder_init)
);

VnColumn * vn_column_combo_new ()
{
	return g_object_new (VN_TYPE_COLUMN_COMBO, NULL);
}

//+++++++++++++++++++++++++++++++++++++++++++++++++++ Private

static void vn_column_combo_set_value (VnColumnCombo * self, GtkTreeModel * model,
	GtkTreeIter * tree_iter, GObject * cell, const GValue * value)
{
	if (self->model && db_model_get_status (self->model) == DB_MODEL_STATUS_READY)
	{
		DbIter iter;

		if (gvn_value_is_null (value))
			g_object_set_property (cell, "text", value);
		else if (db_model_search_value (self->model, self->index_column, &iter, value))
			g_object_set_property (cell, "text",
				db_model_get_value (self->model, &iter, self->show_column, NULL));
	}
}

/*
 * Restores the focus to the tree view after its edition.
 */
static void vn_column_combo_restore_focus (VnColumnCombo * self)
{
	gtk_widget_grab_focus
		(gtk_tree_view_column_get_tree_view (GTK_TREE_VIEW_COLUMN (self)));
}

/*
 * Sets the value of the entry to an empty string if a null value is selected.
 */
static gchar * vn_column_combo_on_format_entry_text (GtkComboBox * combo,
	gchar * path, VnColumnCombo * self)
{
	gchar * str;
	GtkTreeIter iter;

	gtk_tree_model_get_iter_from_string (self->tree, &iter, path);
	gtk_tree_model_get (self->tree, &iter, self->show_column, &str, -1);

	return str ? str : g_strdup ("");
}

/*
 * Sets the autocompletion functionality to the cell being edited.
 */
static void vn_column_combo_on_editing_started (GtkCellRenderer * cell,
	GtkCellEditable * cell_editable, const gchar * path, VnColumnCombo * self)
{
	GtkEntry * entry;

	if (!GTK_IS_COMBO_BOX (cell_editable) || !self->tree)
		return;

	entry = GTK_ENTRY (gtk_bin_get_child (GTK_BIN (cell_editable)));

	// Each edition uses a new cell_editable.
	if (self->cell_editable)
	{
		g_signal_handlers_disconnect_by_func (self->cell_editable,
			vn_column_combo_on_format_entry_text, self);
		g_object_unref (self->cell_editable);
	}

	if (!self->completion_ready)
	{
		gtk_entry_completion_set_model (self->completion, self->tree);
		gtk_entry_completion_set_text_column (self->completion, self->show_column);
		gtk_entry_completion_set_minimum_key_length (self->completion, 1);
		self->completion_ready = TRUE;

		g_signal_connect_swapped (cell_editable, "editing-done",
			G_CALLBACK (vn_column_combo_restore_focus), self);
		self->cell_editable = g_object_ref (cell_editable);
	}

	gtk_entry_set_completion (entry, self->completion);

	g_signal_connect (cell_editable, "format-entry-text",
		G_CALLBACK (vn_column_combo_on_format_entry_text), self);
	self->cell_editable = g_object_ref (cell_editable);
}

/*
 * When the text is edited using an entry, tries to set its underlying value.
 */
static void vn_column_combo_on_edited (GtkCellRendererText * renderer,
	gchar * path, gchar * new_text, VnColumnCombo * self)
{
	DbIter iter;
	GValue value = G_VALUE_INIT;

	if (!g_strcmp0 (new_text, ""))
	{
		g_value_init (&value, GVN_TYPE_NULL);
		VN_COLUMN_GET_CLASS (self)->value_changed (VN_COLUMN (self), path, &value);
	}
	else
	{
		gvn_value_new_with_content (&value, G_TYPE_STRING, new_text);

		if (db_model_search_value (self->model, self->show_column, &iter, &value))
		{
			const GValue * val;

			if ((val = db_model_get_value (self->model, &iter, self->index_column, NULL)))
				VN_COLUMN_GET_CLASS (self)->value_changed (VN_COLUMN (self), path, val);
		}
	}

	g_value_unset (&value);

	vn_column_combo_restore_focus (self);
}

static void vn_column_combo_set_editable (VnColumnCombo * self, gboolean editable)
{
	VnColumn * parent = VN_COLUMN (self);

	if (editable)
	{
		g_signal_connect (parent->cell, "editing-started",
			G_CALLBACK (vn_column_combo_on_editing_started), self);
		g_signal_connect (parent->cell, "edited",
			G_CALLBACK (vn_column_combo_on_edited), self);
		g_signal_connect_swapped (parent->cell, "editing-canceled",
			G_CALLBACK (vn_column_combo_restore_focus), self);

		if (!self->completion)
			self->completion = gtk_entry_completion_new ();
	}
	else
	{
		g_signal_handlers_disconnect_by_data (parent->cell, self);

		if (self->cell_editable)
			g_signal_handlers_disconnect_by_data (self->cell_editable, self);

		if (self->completion)
			g_clear_object (&self->completion);

		self->completion_ready = FALSE;
		self->cell_editable = NULL;
	}

	g_object_set (parent->cell, "editable", editable, NULL);
}

static void vn_column_combo_set_null (VnColumnCombo * self, gboolean null)
{
	if (vn_column_get_model (VN_COLUMN (self)) && self->model)
		vn_list_model_use_null_row (VN_LIST_MODEL (self->tree), null);
}

//+++++++++++++++++++++++++++++++++++++++++++++++++ DbModelHolder implementation

static void vn_column_combo_model_changed (VnColumnCombo * self)
{
	if (self->model)
	{
		vn_list_model_use_null_row (VN_LIST_MODEL (self->tree), VN_COLUMN (self)->null);

		if (self->sort_column >= 0)
			gtk_tree_view_column_set_sort_column_id (
				GTK_TREE_VIEW_COLUMN (self), self->sort_column);
	}
}

static void vn_column_combo_on_status_changed (DbModel * model,
	DbModelStatus status, VnColumnCombo * self)
{
	if (status == DB_MODEL_STATUS_READY)
	{
		g_object_set (VN_COLUMN (self)->cell, "model", self->tree, NULL);
		vn_list_model_use_null_row (VN_LIST_MODEL (self->tree), VN_COLUMN (self)->null);
	}
	else
		g_object_set (VN_COLUMN (self)->cell, "model", NULL, NULL);
}

static void vn_column_combo_set_model (VnColumnCombo * self, DbModel * model)
{
	g_return_if_fail (!model || DB_IS_MODEL (model));

	if (self->model)
	{
		g_signal_handlers_disconnect_by_func (self->model,
			vn_column_combo_on_status_changed, self);
		g_clear_object (&self->model);
		g_clear_object (&self->tree);

		if (self->completion_ready)
			gtk_entry_completion_set_model (self->completion, NULL);
	}

	if (model)
	{
		self->model = g_object_ref (model);
		self->tree = GTK_TREE_MODEL (vn_list_model_new (model));
		g_signal_connect (model, "status-changed",
			G_CALLBACK (vn_column_combo_on_status_changed), self);

		if (self->completion_ready)
			gtk_entry_completion_set_model (self->completion, self->tree);
	}
}

static DbModel * vn_column_combo_get_model (VnColumnCombo * self)
{
	return self->model;
}

//+++++++++++++++++++++++++++++++++++++++++++++++++++ Properties

enum
{
	 PROP_INDEX_COLUMN = 1
	,PROP_SHOW_COLUMN
	,PROP_SORT_COLUMN
	,PROP_MODEL
};

static void vn_column_combo_set_property (VnColumnCombo * self, guint id,
	const GValue * value, GParamSpec * pspec)
{
	switch (id)
	{
		case PROP_INDEX_COLUMN:
			self->index_column = g_value_get_uint (value);
			break;
		case PROP_SHOW_COLUMN:
			self->show_column = g_value_get_uint (value);
			g_object_set (VN_COLUMN (self)->cell, "text-column", self->show_column,
				NULL);
			break;
		case PROP_SORT_COLUMN:
			self->sort_column = g_value_get_int (value);
			break;
		case PROP_MODEL:
			vn_column_combo_set_model (self, g_value_get_object (value));
			break;
		default:
			G_OBJECT_WARN_INVALID_PROPERTY_ID (self, id, pspec);
	}
}

static void vn_column_combo_get_property (VnColumnCombo * self, guint id,
	GValue * value, GParamSpec * pspec)
{
	switch (id)
	{
		case PROP_INDEX_COLUMN:
			g_value_set_uint (value, self->index_column);
			break;
		case PROP_SHOW_COLUMN:
			g_value_set_uint (value, self->show_column);
			break;
		case PROP_SORT_COLUMN:
			g_value_set_int (value, self->sort_column);
			break;
		case PROP_MODEL:
			g_value_set_object (value, self->model);
			break;
		default:
			G_OBJECT_WARN_INVALID_PROPERTY_ID (self, id, pspec);
	}
}

//+++++++++++++++++++++++++++++++++++++++++++++++++++ Class

static void vn_column_combo_init (VnColumnCombo * self)
{
	GtkCellRenderer * cell = gtk_cell_renderer_combo_new ();
	self->model = NULL;
	self->tree = NULL;
	self->completion = NULL;
	self->completion_ready = FALSE;
	self->cell_editable = NULL;

	VN_COLUMN_GET_CLASS (self)->set_renderer (VN_COLUMN (self), cell);
}

static void vn_column_combo_finalize (VnColumnCombo * self)
{
	vn_column_combo_set_model (self, NULL);

	if (self->completion)
		g_object_unref (self->completion);

	G_OBJECT_CLASS (vn_column_combo_parent_class)->finalize (G_OBJECT (self));
}

static void vn_column_combo_class_init (VnColumnComboClass * klass)
{
	GObjectClass * k = G_OBJECT_CLASS (klass);
	k->finalize = (GObjectFinalizeFunc) vn_column_combo_finalize;
	k->set_property = (GObjectSetPropertyFunc) vn_column_combo_set_property;
	k->get_property = (GObjectGetPropertyFunc) vn_column_combo_get_property;
	VN_COLUMN_CLASS (klass)->set_value = (VnColumnSetValueFunc) vn_column_combo_set_value;
	VN_COLUMN_CLASS (klass)->set_editable = (VnColumnSetEditableFunc) vn_column_combo_set_editable;
	VN_COLUMN_CLASS (klass)->set_null = (VnColumnSetNullFunc) vn_column_combo_set_null;
	VN_COLUMN_CLASS (klass)->model_changed = (VnColumnModelChangedFunc) vn_column_combo_model_changed;

	g_object_class_override_property (k, PROP_MODEL, "data-model");

	g_object_class_install_property (k, PROP_INDEX_COLUMN,
		g_param_spec_uint ("index-column"
			,_("Index column")
			,_("The column index of the model")
			,0, 255, 0
			,G_PARAM_CONSTRUCT | G_PARAM_READWRITE
	));
	g_object_class_install_property (k, PROP_SHOW_COLUMN,
		g_param_spec_uint ("show-column"
			,_("Show column")
			,_("The column of the model shown by combo")
			,0, 255, 1
			,G_PARAM_CONSTRUCT | G_PARAM_READWRITE
	));
	g_object_class_install_property (k, PROP_SORT_COLUMN,
		g_param_spec_int ("sort-column"
			,_("Sort column")
			,_("The field number of the Grid model used to sort the column")
			,-1, 255, -1
			,G_PARAM_CONSTRUCT | G_PARAM_READWRITE
	));
}

static void vn_column_combo_model_holder_init (DbModelHolderInterface * iface)
{
	iface->get_model = (DbModelHolderGetModelFunc) vn_column_combo_get_model;
	iface->set_model = (DbModelHolderSetModelFunc) vn_column_combo_set_model;
}