/*
 * Copyright (C) 2012 - 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-field.h"

static void vn_field_param_init					(GvnParamInterface * iface);
static void vn_field_buildable_init				(GtkBuildableIface * iface);
static void vn_field_on_master_value_changed	(GvnParam * master, const GValue * value, VnField * self);

G_DEFINE_ABSTRACT_TYPE_WITH_CODE (VnField, vn_field, GTK_TYPE_EVENT_BOX,
	G_IMPLEMENT_INTERFACE (GVN_TYPE_PARAM,
		vn_field_param_init)
	G_IMPLEMENT_INTERFACE (GTK_TYPE_BUILDABLE,
		vn_field_buildable_init)
);

/**
 * VnFieldStyleFunc:
 * @self: a #VnField
 * @widget: the #GtkWidget held by the field
 * @value: (transfer none): the current value in the cell
 * 
 * Function used to modify the field depending on @value.
 **/

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

static void vn_field_set_invalid (VnField * self, const GError * err)
{
/*	GdkRGBA color = {0.95, 0.8, 0.8, 1};	
	gtk_widget_override_background_color (GTK_WIDGET (self->widget),
		GTK_STATE_FLAG_NORMAL, &color);
*/
}

static void vn_field_update_widget (VnField * self)
{
	self->lock_changed_done = TRUE;
	
	if (VN_FIELD_GET_CLASS (self)->set_value)
		VN_FIELD_GET_CLASS (self)->set_value (self, self->value);

	self->lock_changed_done = FALSE;
}

static void vn_field_changed (VnField * self)
{
	g_signal_emit_by_name (self, "value-changed", self->value);

	if (self->master && self->change_master)
	{
		GError * err = NULL;

		self->change_master = FALSE;

		if (!gvn_param_request_value (self->master, self->value, &err))
		{
			vn_field_set_invalid (self, err);
			g_error_free (err);
		}

		self->change_master = TRUE;
	}

	if (self->style_func)
		self->style_func (self, self->widget, self->value);
}

static void vn_field_value_changed (VnField * self, const GValue * value)
{
	GType type;
	gboolean changed;
	
	if (self->lock_changed_done)
		return;

	type = gvn_param_spec_get_gtype (self->spec);

	if (type != G_TYPE_NONE && !gvn_value_is_null (value))
	{
		if (G_VALUE_TYPE (self->value) != type)
		{
			g_value_unset (self->value);
			g_value_init (self->value, type);
		}
		
		g_value_transform (value, self->value);
		changed = TRUE;
	}
	else
		changed = gvn_value_ccopy (value, self->value);

	if (changed)
		vn_field_changed (self);
}

static void vn_field_spec_changed (VnField * self)
{
	gvn_param_spec_unset (self->spec);
	gvn_param_spec_merge (self->spec, self->user_spec);
	
	if (self->master)
		gvn_param_spec_merge (self->spec,
			gvn_param_get_spec (self->master));

	g_signal_emit_by_name (self, "spec-changed");
}

static void vn_field_set_value (VnField * self, const GValue * value)
{
	if (!gvn_value_ccopy (value, self->value))
		return;

	vn_field_update_widget (self);
	vn_field_changed (self);
}

static const GValue * vn_field_get_value (VnField * self)
{
	return self->value;
}

static gboolean vn_field_request_value (VnField * self, const GValue * value, GError ** err)
{
	if (gvn_param_spec_validate (self->spec, value, err))
	{
		vn_field_set_value (self, value);
		return TRUE;
	}

	return FALSE;
}

static void vn_field_on_master_value_changed (GvnParam * master, const GValue * value, VnField * self)
{
	if (self->change_master)
	{
		self->change_master = FALSE;
		vn_field_set_value (self, value);
		self->change_master = TRUE;
	}
}

static void vn_field_on_master_spec_changed (GvnParam * master, VnField * self)
{
	vn_field_spec_changed (self);
}

static void vn_field_on_master_status_changed (GvnParam * master, VnField * self)
{
	switch (gvn_param_get_status (master))
	{
		case GVN_PARAM_STATUS_OK:
			gtk_widget_set_sensitive (self->widget, TRUE);
			break;
		case GVN_PARAM_STATUS_BUSY:
			gtk_widget_set_sensitive (self->widget, FALSE);
			break;
		case GVN_PARAM_STATUS_ERROR:
//			vn_field_set_invalid (self, gvn_param_get_error (master));
			break;
	}
}

static GvnParam * vn_field_get_master (VnField * self)
{
	return self->master;
}

void vn_field_set_master (VnField * self, GvnParam * master)
{
	if (self->master)
	{
		g_object_disconnect (self->master
			,"any_signal", vn_field_on_master_value_changed, self
			,"any_signal", vn_field_on_master_spec_changed, self
			,"any_signal", vn_field_on_master_status_changed, self
			,NULL
		);
		g_clear_object (&self->master);
	}
	if (master)
	{
		self->master = g_object_ref_sink (master);
		g_object_connect (master
			,"signal::value-changed", vn_field_on_master_value_changed, self
			,"signal::spec-changed", vn_field_on_master_spec_changed, self
			,"signal::status-changed", vn_field_on_master_status_changed, self
			,NULL
		);
		vn_field_on_master_spec_changed (master, self);
		vn_field_on_master_value_changed (master,
			gvn_param_get_value (master), self);
		vn_field_on_master_status_changed (master, self);
	}
	
/*	GFile * css = g_file_new_for_path ("vn/gui/style.css");	
	
	if (g_file_query_exists (css, NULL))
	{
		GError * err = NULL;
		GtkCssProvider * provider = gtk_css_provider_get_default ();
	
		if (gtk_css_provider_load_from_file (provider, css, &err))
		{
			GtkStyleContext * style;
			style = gtk_widget_get_style_context (GTK_WIDGET (self->widget));
			gtk_style_context_add_provider (style, GTK_STYLE_PROVIDER (provider),
				GTK_STYLE_PROVIDER_PRIORITY_USER);
			gtk_style_context_add_class (style, "invalid");
		}
		else
		{
			g_warning ("Vn: %s", err->message);
			g_error_free (err);
		}
	}
	else
		g_warning ("Vn: Can't load CSS styles");
	
	g_object_unref (css);
*/
}

static const GvnParamSpec * vn_field_get_spec (VnField * self)
{
	return self->spec;
}

static GvnParamStatus vn_field_get_status (VnField * self)
{
	return GVN_PARAM_STATUS_OK;
}

static void vn_field_make_param (VnField * self)
{
	GvnParam * param;

	if (!self->iterator || !self->column_name)
		return;

	param = db_iterator_get_param (self->iterator, self->column_name);
	vn_field_set_master (self, param);
}

static void vn_field_set_widget (VnField * self, GtkWidget * widget)
{
	self->widget = widget;
	vn_field_update_widget (self);
}

//+++++++++++++++++++++++++++++++++++++++++++++++++++ Public

/**
 * vn_field_get_gtype:
 * @self: the #VnField
 *
 * Gets the field type.
 *
 * Return value: the field type or %G_TYPE_NONE if it havent.
 **/
GType vn_field_get_gtype (VnField * self)
{
	g_return_val_if_fail (VN_IS_FIELD (self), G_TYPE_INVALID);

	return gvn_param_spec_get_gtype (self->spec);
}

/**
 * vn_field_set_gtype:
 * @self: the #VnField
 * @type: a valid #GType
 *
 * Sets the type of the field. When you set a value, it will be converted to
 * this type.
 **/
void vn_field_set_gtype (VnField * self, GType type)
{
	g_return_if_fail (VN_IS_FIELD (self));

	gvn_param_spec_set_gtype (self->user_spec, type);
	vn_field_spec_changed (self);
}

/**
 * vn_field_get_null:
 * @self: the #VnField
 *
 * If field allows values with %GVN_TYPE_NULL type.
 *
 * Return value: %TRUE if it can, %FALSE otherwise.
 **/
gboolean vn_field_get_null (VnField * self)
{
	g_return_val_if_fail (VN_IS_FIELD (self), FALSE);

	return gvn_param_spec_get_null (self->spec);
}

/**
 * vn_field_set_null:
 * @self: the #VnField
 * @null: %TRUE if field should accept NULL values
 *
 * Sets if field allows values with %GVN_TYPE_NULL type. If param property of
 * the field is set, this attribute will be merged with the same #GvnParam
 * attribute, remaining the most restrictive.
 **/
void vn_field_set_null (VnField * self, gboolean null)
{
	g_return_if_fail (VN_IS_FIELD (self));

	gvn_param_spec_set_null (self->user_spec, null);
	vn_field_spec_changed (self);
}

/**
 * vn_field_get_editable:
 * @self: the #VnField
 *
 * Gets whether the field value can be modified.
 *
 * Return value: %TRUE if field value can be edited, %FALSE otherwise.
 **/
gboolean vn_field_get_editable (VnField * self)
{
	g_return_val_if_fail (VN_IS_FIELD (self), FALSE);

	return gvn_param_spec_get_editable (self->spec);
}

/**
 * vn_field_set_editable:
 * @self: the #VnField
 * @editable: %TRUE if field can be editable
 *
 * Sets if field value can be modified. If param property of
 * the field is set, this attribute will be merged with the same #GvnParam
 * attribute, remaining the most restrictive.
 **/
void vn_field_set_editable (VnField * self, gboolean editable)
{
	g_return_if_fail (VN_IS_FIELD (self));

	gvn_param_spec_set_editable (self->user_spec, editable);
	vn_field_spec_changed (self);
}

/**
 * vn_field_get_default:
 * @self: the #VnField
 **/
const GValue * vn_field_get_default (VnField * self)
{
	g_return_val_if_fail (VN_IS_FIELD (self), NULL);

	return gvn_param_spec_get_default (self->spec);
}

/**
 * vn_field_set_default:
 * @self: the #VnField
 * @def: the default #GValue
 *
 * Sets the default value of the field.
 **/
void vn_field_set_default (VnField * self, const GValue * def)
{
	g_return_if_fail (VN_IS_FIELD (self));

	gvn_param_spec_set_default (self->user_spec, def);
	vn_field_spec_changed (self);
}

/**
 * vn_field_set_to_default:
 * @self: the #VnField
 **/
void vn_field_set_to_default (VnField * self)
{
	g_return_if_fail (VN_IS_FIELD (self));

	vn_field_set_value (self,
		gvn_param_spec_get_default (self->spec));
}

/**
 * vn_field_get_widget:
 * @self: the #VnField
 * 
 * Gets the internal widget of @self.
 * 
 * Return value: (transfer none): the widget
 **/
GtkWidget * vn_field_get_widget (VnField * self)
{
	g_return_if_fail (VN_IS_FIELD (self));

	return self->widget;
}

//+++++++++++++++++++++++++++++++++++++++++++++++++++ Buildable

static GtkBuildableIface *parent_buildable_iface;

static GObject * vn_field_buildable_get_internal_child (GtkBuildable * buildable,
	GtkBuilder * builder, const gchar * childname)
{
	if (!g_strcmp0 (childname, "widget"))
		return G_OBJECT (vn_field_get_widget (VN_FIELD (buildable)));
	return parent_buildable_iface->get_internal_child (buildable, builder, childname);
}

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

enum
{
	 PROP_VALUE = 1
	,PROP_MASTER
	,PROP_ITERATOR
	,PROP_COLUMN_NAME
	,PROP_GTYPE
	,PROP_EDITABLE
	,PROP_NULL
	,PROP_DEFAULT
	,PROP_STYLE_FUNC
};

static void vn_field_set_property (VnField * self, guint id,
	const GValue * value, GParamSpec * pspec)
{
	switch (id)
	{
		case PROP_VALUE:
			vn_field_set_value (self, g_value_get_boxed (value));
			break;
		case PROP_MASTER:
			vn_field_set_master (self, g_value_get_object (value));
			break;
		case PROP_ITERATOR:
			g_clear_object (&self->iterator);
			self->iterator = g_value_dup_object (value);
			vn_field_make_param (self);
			break;
		case PROP_COLUMN_NAME:
			g_free (self->column_name);
			self->column_name = g_value_dup_string (value);
			vn_field_make_param (self);
			break;
		case PROP_GTYPE:
			vn_field_set_gtype (self, g_value_get_gtype (value));
			break;
		case PROP_EDITABLE:
			vn_field_set_editable (self, g_value_get_boolean (value));
			break;
		case PROP_NULL:
			vn_field_set_null (self, g_value_get_boolean (value));
			break;
		case PROP_DEFAULT:
			vn_field_set_default (self, g_value_get_boxed (value));
			break;
		case PROP_STYLE_FUNC:
			self->style_func = g_value_get_pointer (value);
			break;
		default:
			G_OBJECT_WARN_INVALID_PROPERTY_ID (self, id, pspec);
	}
}

static void vn_field_get_property (VnField * self, guint id,
	GValue * value, GParamSpec * pspec)
{
	switch (id)
	{
		case PROP_VALUE:
			g_value_set_boxed (value, self->value);
			break;
		case PROP_MASTER:
			g_value_set_object (value, self->master);
			break;
		case PROP_ITERATOR:
			g_value_set_object (value, self->iterator);
			break;
		case PROP_COLUMN_NAME:
			g_value_set_string (value, self->column_name);
			break;
		case PROP_GTYPE:
			g_value_set_gtype (value, vn_field_get_gtype (self));
			break;
		case PROP_EDITABLE:
			g_value_set_boolean (value, vn_field_get_editable (self));
			break;
		case PROP_NULL:
			g_value_set_boolean (value, vn_field_get_null (self));
			break;
		case PROP_DEFAULT:
			g_value_set_boxed (value, vn_field_get_default (self));
			break;
		case PROP_STYLE_FUNC:
			g_value_set_pointer (value, self->style_func);
			break;
		default:
			G_OBJECT_WARN_INVALID_PROPERTY_ID (self, id, pspec);
	}
}

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

static void vn_field_init (VnField * self)
{
	GdkRGBA color = {0.0, 0.0, 0.0, 0.0};

	self->master = NULL;
	self->change_master = TRUE;
	self->lock_changed_done = FALSE;
	self->user_spec = gvn_param_spec_new ();
	self->spec = gvn_param_spec_new ();
	self->iterator = NULL;
	self->column_name = NULL;
	self->style_func = NULL;
	
	self->value = g_new0 (GValue, 1);
	g_value_init (self->value, GVN_TYPE_NULL);
	
	gtk_widget_override_background_color (GTK_WIDGET (self),
		GTK_STATE_FLAG_NORMAL, &color);
}

static void vn_field_finalize (VnField * self)
{
	gvn_param_spec_free (self->spec);
	gvn_param_spec_free (self->user_spec);
	g_clear_object (&self->iterator);
	vn_field_set_master (self, NULL);
	g_value_unset (self->value);
	g_free (self->value);
	g_free (self->column_name);
	G_OBJECT_CLASS (vn_field_parent_class)->finalize (G_OBJECT (self));
}

static void vn_field_class_init (VnFieldClass * klass)
{
	GObjectClass * k = G_OBJECT_CLASS (klass);
	k->finalize = (GObjectFinalizeFunc) vn_field_finalize;
	k->set_property = (GObjectSetPropertyFunc) vn_field_set_property;
	k->get_property = (GObjectGetPropertyFunc) vn_field_get_property;
	klass->value_changed = vn_field_value_changed;
	klass->set_widget = vn_field_set_widget;

	g_object_class_override_property (k, PROP_VALUE, "value");
	g_object_class_override_property (k, PROP_MASTER, "master");

	g_object_class_install_property (k, PROP_ITERATOR,
		g_param_spec_object ("iterator"
			,_("Iterator")
			,_("The iterator used to get the field param")
			,DB_TYPE_ITERATOR
			,G_PARAM_READWRITE
	));
	g_object_class_install_property (k, PROP_COLUMN_NAME,
		g_param_spec_string ("column-name"
			,_("Column name")
			,_("The column name on the iterator")
			,NULL
			,G_PARAM_READWRITE
	));
	g_object_class_install_property (k, PROP_GTYPE,
		g_param_spec_gtype ("gtype"
			,_("Glib Type")
			,_("The type of the value")
			,G_TYPE_NONE
			,G_PARAM_CONSTRUCT | G_PARAM_READWRITE
	));
	g_object_class_install_property (k, PROP_EDITABLE,
		g_param_spec_boolean ("editable"
			,_("Editable")
			,_("Whether the field value is user editable")
			,TRUE
			,G_PARAM_CONSTRUCT | G_PARAM_READWRITE
	));
	g_object_class_install_property (k, PROP_NULL,
		g_param_spec_boolean ("null"
			,_("Null")
			,_("Whether the field value can be of type GVN_TYPE_NULL")
			,TRUE
			,G_PARAM_CONSTRUCT | G_PARAM_READWRITE
	));
	g_object_class_install_property (k, PROP_DEFAULT,
		g_param_spec_boxed ("default"
			,_("Default Value")
			,_("The default value")
			,G_TYPE_VALUE
			,G_PARAM_READWRITE
	));
	g_object_class_install_property (k, PROP_STYLE_FUNC,
		g_param_spec_pointer ("style-func"
			,_("Style function")
			,_("A VnFieldStyleFunc to set the properties of each field "
			"depending on its value")
			,G_PARAM_CONSTRUCT | G_PARAM_READWRITE
	));
}

static void vn_field_buildable_init (GtkBuildableIface * iface)
{
	parent_buildable_iface = g_type_interface_peek_parent (iface);
	iface->get_internal_child = vn_field_buildable_get_internal_child;
}

static void vn_field_param_init (GvnParamInterface * iface)
{
	iface->get_value = (GvnParamGetValueFunc) vn_field_get_value;
	iface->request_value = (GvnParamRequestValueFunc) vn_field_request_value;
	iface->get_master = (GvnParamGetMasterFunc) vn_field_get_master;
	iface->set_master = (GvnParamSetMasterFunc) vn_field_set_master;
	iface->get_spec = (GvnParamGetSpecFunc) vn_field_get_spec;
	iface->get_status = (GvnParamGetStatusFunc) vn_field_get_status;
}