/*
 * e-activity-bar.c
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) version 3.
 *
 * 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with the program; if not, see <http://www.gnu.org/licenses/>
 *
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include "e-activity-bar.h"

#define E_ACTIVITY_BAR_GET_PRIVATE(obj) \
	(G_TYPE_INSTANCE_GET_PRIVATE \
	((obj), E_TYPE_ACTIVITY_BAR, EActivityBarPrivate))

#define FEEDBACK_PERIOD		1 /* seconds */
#define COMPLETED_ICON_NAME	"emblem-default"

struct _EActivityBarPrivate {
	EActivity *activity;	/* weak reference */
	GtkWidget *image;	/* not referenced */
	GtkWidget *label;	/* not referenced */
	GtkWidget *cancel;	/* not referenced */
	GtkWidget *spinner;	/* not referenced */

	/* If the user clicks the Cancel button, keep the cancelled
	 * EActivity object alive for a short duration so the user
	 * gets some visual feedback that cancellation worked. */
	guint timeout_id;
};

enum {
	PROP_0,
	PROP_ACTIVITY
};

G_DEFINE_TYPE (
	EActivityBar,
	e_activity_bar,
	GTK_TYPE_INFO_BAR)

static void
activity_bar_feedback (EActivityBar *bar)
{
	EActivity *activity;
	EActivityState state;

	activity = e_activity_bar_get_activity (bar);
	g_return_if_fail (E_IS_ACTIVITY (activity));

	state = e_activity_get_state (activity);
	if (state != E_ACTIVITY_CANCELLED && state != E_ACTIVITY_COMPLETED)
		return;

	if (bar->priv->timeout_id > 0)
		g_source_remove (bar->priv->timeout_id);

	/* Hold a reference on the EActivity for a short
	 * period so the activity bar stays visible. */
	bar->priv->timeout_id = g_timeout_add_seconds_full (
		G_PRIORITY_LOW, FEEDBACK_PERIOD, (GSourceFunc) gtk_false,
		g_object_ref (activity), (GDestroyNotify) g_object_unref);
}

static void
activity_bar_update (EActivityBar *bar)
{
	EActivity *activity;
	EActivityState state;
	GCancellable *cancellable;
	const gchar *icon_name;
	gboolean sensitive;
	gboolean visible;
	gchar *description;

	activity = e_activity_bar_get_activity (bar);

	if (activity == NULL) {
		gtk_widget_hide (GTK_WIDGET (bar));
		return;
	}

	cancellable = e_activity_get_cancellable (activity);
	icon_name = e_activity_get_icon_name (activity);
	state = e_activity_get_state (activity);

	description = e_activity_describe (activity);
	gtk_label_set_text (GTK_LABEL (bar->priv->label), description);

	if (state == E_ACTIVITY_CANCELLED) {
		PangoAttribute *attr;
		PangoAttrList *attr_list;

		attr_list = pango_attr_list_new ();

		attr = pango_attr_strikethrough_new (TRUE);
		pango_attr_list_insert (attr_list, attr);

		gtk_label_set_attributes (
			GTK_LABEL (bar->priv->label), attr_list);

		pango_attr_list_unref (attr_list);
	} else
		gtk_label_set_attributes (
			GTK_LABEL (bar->priv->label), NULL);

	if (state == E_ACTIVITY_COMPLETED)
		icon_name = COMPLETED_ICON_NAME;

	if (state == E_ACTIVITY_CANCELLED) {
		gtk_image_set_from_stock (
			GTK_IMAGE (bar->priv->image),
			GTK_STOCK_CANCEL, GTK_ICON_SIZE_BUTTON);
		gtk_widget_show (bar->priv->image);
	} else if (icon_name != NULL) {
		gtk_image_set_from_icon_name (
			GTK_IMAGE (bar->priv->image),
			icon_name, GTK_ICON_SIZE_BUTTON);
		gtk_widget_show (bar->priv->image);
	} else {
		gtk_widget_hide (bar->priv->image);
	}

	visible = (cancellable != NULL);
	gtk_widget_set_visible (bar->priv->cancel, visible);

	sensitive = (state == E_ACTIVITY_RUNNING);
	gtk_widget_set_sensitive (bar->priv->cancel, sensitive);

	visible = (description != NULL && *description != '\0');
	gtk_widget_set_visible (GTK_WIDGET (bar), visible);

	g_free (description);
}

static void
activity_bar_cancel (EActivityBar *bar)
{
	EActivity *activity;

	activity = e_activity_bar_get_activity (bar);
	g_return_if_fail (E_IS_ACTIVITY (activity));

	e_activity_cancel (activity);

	activity_bar_update (bar);
}

static void
activity_bar_weak_notify_cb (EActivityBar *bar,
                             GObject *where_the_object_was)
{
	g_return_if_fail (E_IS_ACTIVITY_BAR (bar));

	bar->priv->activity = NULL;
	e_activity_bar_set_activity (bar, NULL);
}

static void
activity_bar_set_property (GObject *object,
                           guint property_id,
                           const GValue *value,
                           GParamSpec *pspec)
{
	switch (property_id) {
		case PROP_ACTIVITY:
			e_activity_bar_set_activity (
				E_ACTIVITY_BAR (object),
				g_value_get_object (value));
			return;
	}

	G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
}

static void
activity_bar_get_property (GObject *object,
                           guint property_id,
                           GValue *value,
                           GParamSpec *pspec)
{
	switch (property_id) {
		case PROP_ACTIVITY:
			g_value_set_object (
				value, e_activity_bar_get_activity (
				E_ACTIVITY_BAR (object)));
			return;
	}

	G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
}

static void
activity_bar_dispose (GObject *object)
{
	EActivityBarPrivate *priv;

	priv = E_ACTIVITY_BAR_GET_PRIVATE (object);

	if (priv->timeout_id > 0) {
		g_source_remove (priv->timeout_id);
		priv->timeout_id = 0;
	}

	if (priv->activity != NULL) {
		g_signal_handlers_disconnect_matched (
			priv->activity, G_SIGNAL_MATCH_DATA,
			0, 0, NULL, NULL, object);
		g_object_weak_unref (
			G_OBJECT (priv->activity), (GWeakNotify)
			activity_bar_weak_notify_cb, object);
		priv->activity = NULL;
	}

	/* Chain up to parent's dispose() method. */
	G_OBJECT_CLASS (e_activity_bar_parent_class)->dispose (object);
}

static void
e_activity_bar_class_init (EActivityBarClass *class)
{
	GObjectClass *object_class;

	g_type_class_add_private (class, sizeof (EActivityBarPrivate));

	object_class = G_OBJECT_CLASS (class);
	object_class->set_property = activity_bar_set_property;
	object_class->get_property = activity_bar_get_property;
	object_class->dispose = activity_bar_dispose;

	g_object_class_install_property (
		object_class,
		PROP_ACTIVITY,
		g_param_spec_object (
			"activity",
			NULL,
			NULL,
			E_TYPE_ACTIVITY,
			G_PARAM_READWRITE |
			G_PARAM_CONSTRUCT));
}

static void
e_activity_bar_init (EActivityBar *bar)
{
	GtkWidget *container;
	GtkWidget *widget;

	bar->priv = E_ACTIVITY_BAR_GET_PRIVATE (bar);

	container = gtk_info_bar_get_content_area (GTK_INFO_BAR (bar));

	widget = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 12);
	gtk_container_add (GTK_CONTAINER (container), widget);
	gtk_widget_show (widget);

	container = widget;

	widget = gtk_image_new ();
	gtk_box_pack_start (GTK_BOX (container), widget, FALSE, FALSE, 0);
	bar->priv->image = widget;

	widget = gtk_spinner_new ();
	gtk_spinner_start (GTK_SPINNER (widget));
	gtk_box_pack_start (GTK_BOX (container), widget, FALSE, FALSE, 0);
	bar->priv->spinner = widget;

	/* The spinner is only visible when the image is not. */
	g_object_bind_property (
		bar->priv->image, "visible",
		bar->priv->spinner, "visible",
		G_BINDING_BIDIRECTIONAL |
		G_BINDING_SYNC_CREATE |
		G_BINDING_INVERT_BOOLEAN);

	widget = gtk_label_new (NULL);
	gtk_misc_set_alignment (GTK_MISC (widget), 0.0, 0.5);
	gtk_label_set_ellipsize (GTK_LABEL (widget), PANGO_ELLIPSIZE_END);
	gtk_box_pack_start (GTK_BOX (container), widget, TRUE, TRUE, 0);
	bar->priv->label = widget;
	gtk_widget_show (widget);

	/* This is only shown if the EActivity has a GCancellable. */
	widget = gtk_button_new_from_stock (GTK_STOCK_CANCEL);
	gtk_info_bar_add_action_widget (
		GTK_INFO_BAR (bar), widget, GTK_RESPONSE_CANCEL);
	bar->priv->cancel = widget;
	gtk_widget_hide (widget);

	g_signal_connect_swapped (
		widget, "clicked",
		G_CALLBACK (activity_bar_cancel), bar);
}

GtkWidget *
e_activity_bar_new (void)
{
	return g_object_new (E_TYPE_ACTIVITY_BAR, NULL);
}

EActivity *
e_activity_bar_get_activity (EActivityBar *bar)
{
	g_return_val_if_fail (E_IS_ACTIVITY_BAR (bar), NULL);

	return bar->priv->activity;
}

void
e_activity_bar_set_activity (EActivityBar *bar,
                             EActivity *activity)
{
	g_return_if_fail (E_IS_ACTIVITY_BAR (bar));

	if (activity != NULL)
		g_return_if_fail (E_IS_ACTIVITY (activity));

	if (bar->priv->timeout_id > 0) {
		g_source_remove (bar->priv->timeout_id);
		bar->priv->timeout_id = 0;
	}

	if (bar->priv->activity != NULL) {
		g_signal_handlers_disconnect_matched (
			bar->priv->activity, G_SIGNAL_MATCH_DATA,
			0, 0, NULL, NULL, bar);
		g_object_weak_unref (
			G_OBJECT (bar->priv->activity),
			(GWeakNotify) activity_bar_weak_notify_cb, bar);
	}

	bar->priv->activity = activity;

	if (activity != NULL) {
		g_object_weak_ref (
			G_OBJECT (activity), (GWeakNotify)
			activity_bar_weak_notify_cb, bar);

		g_signal_connect_swapped (
			activity, "notify::state",
			G_CALLBACK (activity_bar_feedback), bar);

		g_signal_connect_swapped (
			activity, "notify",
			G_CALLBACK (activity_bar_update), bar);
	}

	activity_bar_update (bar);

	g_object_notify (G_OBJECT (bar), "activity");
}