/*
 * Copyright 2015 Javier S. Pedro <dev.git@javispedro.com>
 *
 * This file is part of MDock.
 *
 * MDock 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.
 *
 * MDock 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 General Public License
 * along with MDock.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <math.h>
#include "mdock-item.h"

#define MDOCK_ITEM_GET_PRIVATE(object)(G_TYPE_INSTANCE_GET_PRIVATE((object), MDOCK_TYPE_ITEM, MDockItemPrivate))

#define REQUISITION_ICON_SIZE 32

struct _MDockItemPrivate
{
	gboolean pinned;
	GDesktopAppInfo *appinfo;
	guint icon_size;
	GdkPixbuf *icon;
	GList *windows;
	gboolean needs_attention;
};

G_DEFINE_TYPE (MDockItem, mdock_item, GTK_TYPE_WIDGET)

enum {
	PROP_0,
	PROP_PINNED,
	PROP_DESKTOP_APP_INFO,
	PROP_N_WINDOWS,
	PROP_DISPLAY_NAME,
	PROP_NEEDS_ATTENTION,
	N_PROPERTIES
};

static GParamSpec *obj_properties[N_PROPERTIES] = { NULL };

static GdkPixbuf *mdock_item_load_icon(MDockItem *self, guint icon_size)
{
	if (self->priv->appinfo) {
		GtkIconTheme *theme = gtk_icon_theme_get_default();
		GIcon *icon = g_app_info_get_icon(G_APP_INFO(self->priv->appinfo));
		if (icon) {
			GtkIconInfo *info = gtk_icon_theme_lookup_by_gicon(theme, icon, icon_size,
			                                                   GTK_ICON_LOOKUP_GENERIC_FALLBACK | GTK_ICON_LOOKUP_FORCE_SIZE);
			GdkPixbuf *pixbuf = gtk_icon_info_load_icon(info, NULL);
			gtk_icon_info_free(info);
			if (pixbuf) {
				return pixbuf;
			}
		}
	}

	if (self->priv->windows) {
		GdkPixbuf *pixbuf = wnck_window_get_icon(self->priv->windows->data);
		if (pixbuf) {
			return gdk_pixbuf_scale_simple(pixbuf, self->priv->icon_size, icon_size, GDK_INTERP_BILINEAR);
		}
	}

	return NULL;
}

static void mdock_item_update_icon(MDockItem *self)
{
	g_clear_object(&self->priv->icon);
	self->priv->icon = mdock_item_load_icon(self, self->priv->icon_size);
	gtk_widget_queue_draw(GTK_WIDGET(self));
}

static void mdock_item_update_icon_geometry_for_window(MDockItem *self, WnckWindow *window)
{
	if (!gtk_widget_get_realized(GTK_WIDGET(self))) return;

	GdkWindow *self_window = gtk_widget_get_window(GTK_WIDGET(self));
	gint x, y, width, height;
	gdk_window_get_origin(self_window, &x, &y);
	gdk_window_get_size(self_window, &width, &height);

	wnck_window_set_icon_geometry(window, x, y, width, height);
}

static void mdock_item_update_icon_geometry(MDockItem *self)
{
	if (!gtk_widget_get_realized(GTK_WIDGET(self))) return;
	if (!self->priv->windows) return;

	GdkWindow *self_window = gtk_widget_get_window(GTK_WIDGET(self));
	gint x, y, width, height;
	gdk_window_get_origin(self_window, &x, &y);
	gdk_window_get_size(self_window, &width, &height);

	for (GList *l = self->priv->windows; l; l = g_list_next(l)) {
		WnckWindow *window = WNCK_WINDOW(l->data);
		wnck_window_set_icon_geometry(window, x, y, width, height);
	}
}

static void mdock_item_update_needs_attention(MDockItem *self)
{
	gboolean needs_it = FALSE;

	for (GList *l = self->priv->windows; l; l = g_list_next(l)) {
		WnckWindow *window = WNCK_WINDOW(l->data);
		needs_it |= wnck_window_or_transient_needs_attention(window);
	}

	if (needs_it != self->priv->needs_attention) {
		self->priv->needs_attention = needs_it;
		gtk_widget_queue_draw(GTK_WIDGET(self));
		g_object_notify_by_pspec(G_OBJECT(self),
		                         obj_properties[PROP_NEEDS_ATTENTION]);
	}
}

static void handle_window_state_changed(WnckWindow *window, WnckWindowState changed_mask, WnckWindowState new_state, MDockItem *self)
{
	if (changed_mask & (WNCK_WINDOW_STATE_DEMANDS_ATTENTION | WNCK_WINDOW_STATE_URGENT)) {
		mdock_item_update_needs_attention(self);
	}
}

static void mdock_item_realize(GtkWidget *widget)
{
	MDockItem *self = MDOCK_ITEM(widget);
	GdkWindowAttr attributes;
	guint attributes_mask;

	attributes.window_type = GDK_WINDOW_CHILD;
	attributes.x = widget->allocation.x;
	attributes.y = widget->allocation.y;
	attributes.width = widget->allocation.width;
	attributes.height = widget->allocation.height;

	attributes.wclass = GDK_INPUT_OUTPUT;
	attributes.event_mask = gtk_widget_get_events(widget) | GDK_EXPOSURE_MASK;

	attributes_mask = GDK_WA_X | GDK_WA_Y;

	widget->window = gdk_window_new(gtk_widget_get_parent_window(widget), &attributes, attributes_mask);

	gdk_window_set_back_pixmap(widget->window, NULL, TRUE);
	gdk_window_set_user_data(widget->window, widget);
	gtk_widget_set_realized(widget, TRUE);

	widget->style = gtk_style_attach(widget->style, widget->window);

	mdock_item_update_icon_geometry(self);
}

static void mdock_item_size_request(GtkWidget *widget, GtkRequisition *requisition)
{
	requisition->width = requisition->height = REQUISITION_ICON_SIZE;
}

static void mdock_item_size_allocate(GtkWidget *widget, GtkAllocation *allocation)
{
	MDockItem *self = MDOCK_ITEM(widget);
	self->priv->icon_size = MIN(allocation->width, allocation->height);
	GTK_WIDGET_CLASS(mdock_item_parent_class)->size_allocate(widget, allocation);
	mdock_item_update_icon(self);
	mdock_item_update_icon_geometry(self);
}

static gboolean mdock_item_expose(GtkWidget *widget, GdkEventExpose *event)
{
	MDockItem *self = MDOCK_ITEM(widget);
	cairo_t *cr = gdk_cairo_create(widget->window);

	if (self->priv->icon) {
		cairo_save(cr);
		gdk_cairo_set_source_pixbuf(cr, self->priv->icon, 0, 0);
		cairo_paint(cr);
		cairo_restore(cr);
	}
	if (self->priv->windows) {
		double circle_radius = self->priv->icon_size / 8.0;
		cairo_save(cr);
		if (self->priv->needs_attention) {
			cairo_set_source_rgba(cr, 0.9, 0.3, 0.3, 1.0);
		} else {
			cairo_set_source_rgba(cr, 0.4, 0.4, 0.6, 0.8);
		}
		cairo_translate(cr, self->priv->icon_size / 2.0, self->priv->icon_size - circle_radius / 2.0 - 1.0);
		cairo_arc(cr, 0, 0, circle_radius, 0, 2 * M_PI);
		cairo_fill(cr);
		cairo_restore(cr);
	}

	cairo_destroy(cr);

	return FALSE;
}

static void mdock_item_set_property(GObject        *object,
                                    guint           property_id,
                                    const GValue   *value,
                                    GParamSpec     *pspec)
{
	MDockItem *self = MDOCK_ITEM(object);
	switch (property_id) {
	case PROP_PINNED:
		self->priv->pinned = g_value_get_boolean(value);
		break;
	case PROP_DESKTOP_APP_INFO:
		self->priv->appinfo = g_value_dup_object(value);
		mdock_item_update_icon(self);
		break;
	default:
		G_OBJECT_WARN_INVALID_PROPERTY_ID(object, property_id, pspec);
		break;
	}
}

static void mdock_item_get_property(GObject        *object,
                                    guint           property_id,
                                    GValue         *value,
                                    GParamSpec     *pspec)
{
	MDockItem *self = MDOCK_ITEM(object);
	switch (property_id) {
	case PROP_PINNED:
		g_value_set_boolean(value, self->priv->pinned);
		break;
	case PROP_DESKTOP_APP_INFO:
		g_value_set_object(value, self->priv->appinfo);
		break;
	case PROP_N_WINDOWS:
		g_value_set_uint(value, g_list_length(self->priv->windows));
		break;
	case PROP_DISPLAY_NAME:
		g_value_set_string(value, mdock_item_get_display_name(self));
		break;
	case PROP_NEEDS_ATTENTION:
		g_value_set_boolean(value, self->priv->needs_attention);
		break;
	default:
		G_OBJECT_WARN_INVALID_PROPERTY_ID(object, property_id, pspec);
		break;
	}
}

static void mdock_item_dispose(GObject *object)
{
	MDockItem *self = MDOCK_ITEM(object);
	g_clear_object(&self->priv->appinfo);
	g_clear_object(&self->priv->icon);
	G_OBJECT_CLASS(mdock_item_parent_class)->dispose(object);
}

static void mdock_item_finalize(GObject *object)
{
	MDockItem *self = MDOCK_ITEM(object);
	g_list_free(self->priv->windows);
	G_OBJECT_CLASS(mdock_item_parent_class)->finalize(object);
}

static void mdock_item_init(MDockItem *self)
{
	self->priv = MDOCK_ITEM_GET_PRIVATE (self);
	self->priv->pinned = FALSE;
	self->priv->icon_size = REQUISITION_ICON_SIZE;
	self->priv->needs_attention = FALSE;

	gtk_widget_add_events(GTK_WIDGET(self),
	                      GDK_BUTTON_PRESS_MASK | GDK_ENTER_NOTIFY_MASK | GDK_LEAVE_NOTIFY_MASK);
}

static void
mdock_item_class_init(MDockItemClass *klass)
{
	GObjectClass *obj_class = G_OBJECT_CLASS (klass);
	obj_class->set_property = mdock_item_set_property;
	obj_class->get_property = mdock_item_get_property;
	obj_class->dispose = mdock_item_dispose;
	obj_class->finalize = mdock_item_finalize;

	GtkWidgetClass *widget_class = GTK_WIDGET_CLASS(klass);
	widget_class->realize = mdock_item_realize;
	widget_class->size_request = mdock_item_size_request;
	widget_class->size_allocate = mdock_item_size_allocate;
	widget_class->expose_event = mdock_item_expose;

	obj_properties[PROP_PINNED] = g_param_spec_boolean("pinned",
	                                                   "Pinned launcher",
	                                                   "Set whether this launcher is pinned",
	                                                   FALSE,
	                                                   G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS);

	obj_properties[PROP_DESKTOP_APP_INFO] = g_param_spec_object("desktop-app-info",
	                                                            "The GDesktopAppInfo this application or launcher refers to",
	                                                            "Set the GDesktopAppInfo this application or launcher refers to",
	                                                            G_TYPE_DESKTOP_APP_INFO,
	                                                            G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS);

	obj_properties[PROP_N_WINDOWS] = g_param_spec_uint("n-windows",
	                                                   "Number of windows",
	                                                   "Reads the current number of windows under this item",
	                                                   0, G_MAXINT32,
	                                                   0,
	                                                   G_PARAM_READABLE | G_PARAM_STATIC_STRINGS);

	obj_properties[PROP_DISPLAY_NAME] = g_param_spec_string("display-name",
	                                                        "Name of this item",
	                                                        "Reads the current name of this item",
	                                                        "",
	                                                        G_PARAM_READABLE | G_PARAM_STATIC_STRINGS);

	obj_properties[PROP_NEEDS_ATTENTION] = g_param_spec_boolean("needs-attention",
	                                                            "Needs attention",
	                                                            "Whether any of the windows in this item requires attention",
	                                                            FALSE,
	                                                            G_PARAM_READABLE | G_PARAM_STATIC_STRINGS);

	g_object_class_install_properties(obj_class, N_PROPERTIES, obj_properties);

	g_type_class_add_private (obj_class, sizeof (MDockItemPrivate));
}

MDockItem *mdock_item_new()
{
	return g_object_new(MDOCK_TYPE_ITEM, NULL);
}

gboolean mdock_item_get_pinned(MDockItem *self)
{
	return self->priv->pinned;
}

void mdock_item_set_pinned(MDockItem *self, gboolean pinned)
{
	g_object_set(self, "pinned", pinned, NULL);
}

void mdock_item_toggle_pinned(MDockItem *self)
{
	mdock_item_set_pinned(self, !self->priv->pinned);
}

GDesktopAppInfo *mdock_item_get_desktop_app_info(MDockItem *self)
{
	return self->priv->appinfo;
}

void mdock_item_set_desktop_app_info(MDockItem *self, GDesktopAppInfo *app_info)
{
	g_object_set(self, "desktop-app-info", app_info, NULL);
}

void mdock_item_launch_files(MDockItem *self, GList *files)
{
	g_return_if_fail(self->priv->appinfo);
	GAppInfo *appinfo = G_APP_INFO(self->priv->appinfo);
	GdkAppLaunchContext *launch_context = gdk_app_launch_context_new();
	GError *error = NULL;

	gdk_app_launch_context_set_display(launch_context, gtk_widget_get_display(GTK_WIDGET(self)));
	gdk_app_launch_context_set_timestamp(launch_context, gtk_get_current_event_time());

	g_debug("Launching '%s'", g_app_info_get_commandline(appinfo));

	if (!g_app_info_launch(appinfo, files, G_APP_LAUNCH_CONTEXT(launch_context), &error)) {
		GtkWidget *msg;

		g_warning("Cannot launch '%s': %s",
		          g_app_info_get_display_name(appinfo),
                  error->message);

		msg = gtk_message_dialog_new(GTK_WINDOW(gtk_widget_get_toplevel(GTK_WIDGET(self))),
		                             GTK_DIALOG_DESTROY_WITH_PARENT,
		                             GTK_MESSAGE_WARNING,
		                             GTK_BUTTONS_OK,
		                             "Cannot launch '%s': %s",
		                             g_app_info_get_display_name(appinfo),
		                             error->message);

		g_signal_connect_swapped(msg, "response",
		                         G_CALLBACK(gtk_widget_destroy), msg);

		gtk_widget_show_all(msg);
		g_error_free(error);
	}


}

void mdock_item_launch_file(MDockItem *self, GFile *file)
{
	GList *files = g_list_append(NULL, file);
	mdock_item_launch_files(self, files);
	g_list_free(files);
}

void mdock_item_launch(MDockItem *self)
{
	mdock_item_launch_files(self, NULL);
}

const gchar *mdock_item_get_display_name(MDockItem *self)
{
	if (self->priv->appinfo) {
		return g_app_info_get_display_name(G_APP_INFO(self->priv->appinfo));
	} else if (self->priv->windows) {
		WnckApplication *app = wnck_window_get_application(self->priv->windows->data);
		return wnck_application_get_name(app);
	} else {
		return NULL;
	}
}

GdkPixbuf *mdock_item_get_icon_pixbuf(MDockItem *self)
{
	return self->priv->icon;
}

gboolean mdock_item_needs_attention(MDockItem *self)
{
	return self->priv->needs_attention;
}

void mdock_item_add_window(MDockItem *self, WnckWindow *window)
{
	if (!self->priv->windows) {
		// If there were no windows before adding this one,
		// we want to redraw in order to get the "active" indicator.
		gtk_widget_queue_draw(GTK_WIDGET(self));
	}
	self->priv->windows = g_list_append(self->priv->windows, window);
	if (!self->priv->icon) {
		mdock_item_update_icon(self);
	}
	mdock_item_update_icon_geometry_for_window(self, window);
	if (wnck_window_or_transient_needs_attention(window)) {
		mdock_item_update_needs_attention(self);
	}
	g_signal_connect_object(window, "state-changed",
	                        G_CALLBACK(handle_window_state_changed), self, 0);
	g_object_notify_by_pspec(G_OBJECT(self), obj_properties[PROP_N_WINDOWS]);
}

void mdock_item_remove_window(MDockItem *self, WnckWindow *window)
{
	self->priv->windows = g_list_remove(self->priv->windows, window);
	if (!self->priv->windows) {
		// If there are no windows left,
		// we want to redraw in order to remove the "active" indicator.
		gtk_widget_queue_draw(GTK_WIDGET(self));
	}
	if (wnck_window_or_transient_needs_attention(window)) {
		mdock_item_update_needs_attention(self);
	}
	g_signal_handlers_disconnect_by_data(window, self);
	g_object_notify_by_pspec(G_OBJECT(self), obj_properties[PROP_N_WINDOWS]);
}

void mdock_item_set_last_active_window(MDockItem *self, WnckWindow *window)
{
	g_return_if_fail(self->priv->windows);
	if (self->priv->windows->data == window) {
		return; // Nothing to do
	}

	// Move the last active window to the head of the window list.
	GList *l = g_list_find(self->priv->windows, window);
	g_return_if_fail(l);

	self->priv->windows = g_list_remove_link(self->priv->windows, l);
	self->priv->windows = g_list_concat(l, self->priv->windows);
}

gint mdock_item_get_num_windows(MDockItem *self)
{
	return g_list_length(self->priv->windows);
}

gboolean mdock_item_has_windows(MDockItem *self)
{
	return self->priv->windows ? TRUE : FALSE;
}

void mdock_item_close_all_windows(MDockItem *self)
{
	for (GList *l = self->priv->windows; l; l = g_list_next(l)) {
		WnckWindow *window = WNCK_WINDOW(l->data);
		wnck_window_close(window, GDK_CURRENT_TIME);
	}
}

void mdock_item_update_background(MDockItem *self)
{
	GtkWidget *widget = GTK_WIDGET(self);
	GdkWindow *window = gtk_widget_get_window(widget);
	g_return_if_fail(window);
	gdk_window_set_back_pixmap(window, NULL, TRUE);
	gtk_widget_queue_draw(widget);
}

void mdock_item_activate(MDockItem *self)
{
	if (self->priv->windows) {
		// This item has one window at least
		if (self->priv->windows->next) {
			// There is more than one window
			gboolean found_window = FALSE;
			for (GList *l = self->priv->windows; l; l = g_list_next(l)) {
				WnckWindow *window = WNCK_WINDOW(l->data);
				if (wnck_window_is_most_recently_activated(window)
				        || wnck_window_transient_is_most_recently_activated(window)) {
					// This is the currently focused window, let's focus the next in the list
					GList *n = l->next ? g_list_next(l) : self->priv->windows;
					window = WNCK_WINDOW(n->data);
					wnck_window_activate_transient(window, gtk_get_current_event_time());
					found_window = TRUE;
					break;
				}
			}
			if (!found_window) {
				WnckWindow *window = WNCK_WINDOW(self->priv->windows->data);
				wnck_window_activate_transient(window, gtk_get_current_event_time());
			}
		} else {
			// There is only one window in this group
			WnckWindow *window = WNCK_WINDOW(self->priv->windows->data);
			if (wnck_window_is_minimized(window)) {
				wnck_window_unminimize(window, gtk_get_current_event_time());
			} else if (wnck_window_is_most_recently_activated(window)
			           || wnck_window_transient_is_most_recently_activated(window)) {
				wnck_window_minimize(window);
			} else {
				wnck_window_activate_transient(window, gtk_get_current_event_time());
			}
		}
	} else if (self->priv->appinfo) {
		// No windows, but we have an application to launch!
		mdock_item_launch(self);
	} else {
		g_warning("A MDockItem has no windows and no appinfo to launch");
	}
}