/*
 * Copyright (C) 2005-2009 Alex Murray <murray.alex@gmail.com>
 *
 * 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 2 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, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */

/** Contain the functions for operating on the SensorsApplet structure
 *  (represents the applet itself, and its associated variables.
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif /* HAVE_CONFIG_H */

#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif /* HAVE_UNISTD_H */

#include <glib/gi18n.h>
#include <glib/gprintf.h>
#include <gio/gio.h>
#include "sensors-applet.h"
#include "active-sensor.h"
#include "sensors-applet-settings.h"
#include "sensors-applet-plugins.h"

#ifdef HAVE_LIBNOTIFY
#include "active-sensor-libnotify.h"
#define DEFAULT_NOTIFY_TIMEOUT 3000
#endif

#include "prefs-dialog.h"
#include "about-dialog.h"

#define SENSORS_APPLET_MENU_FILE "SensorsApplet.xml"
#define DEFAULT_APPLET_SIZE 24 /* initially set as
                                * sensors_applet->size to ensure a
                                * real value is stored */
#define COLUMN_SPACING 2
#define ROW_SPACING 0

/* callbacks for panel menu */
static void prefs_cb(GtkAction *action,
		     gpointer *data) {

        SensorsApplet *sensors_applet;
        sensors_applet = (SensorsApplet *)data;

	if (sensors_applet->prefs_dialog) {
		gtk_window_present(GTK_WINDOW(sensors_applet->prefs_dialog->dialog));
		return;
	}
	prefs_dialog_open(sensors_applet);
}

static void about_cb(GtkAction *action,
		     gpointer data) {
        SensorsApplet *sensors_applet;
        sensors_applet = (SensorsApplet *)data;

	about_dialog_open(sensors_applet);
}

static void help_cb(GtkAction *action, 
                    gpointer data) {

        GError *error = NULL;
        
        gtk_show_uri(NULL, "http://wiki.mate-desktop.org/docs:mate-sensors-applet",
		     gtk_get_current_event_time(),
		     &error);
        
        if (error) {
                g_debug("Could not open help document: %s ",error->message);
                g_error_free(error);
        }
}

static void destroy_cb(GtkWidget *widget, gpointer data) {
        SensorsApplet *sensors_applet;
        sensors_applet = (SensorsApplet *)data;

	/* destory dialogs, remove timeout and clear sensors tree and finally
         * the applet */
	if (sensors_applet->prefs_dialog != NULL) {
                // destroy's dialog too
                prefs_dialog_close(sensors_applet);
	}

	if (sensors_applet->timeout_id) {
		g_source_remove(sensors_applet->timeout_id);
	}

	if (sensors_applet->settings) {
		g_object_unref (sensors_applet->settings);
		sensors_applet->settings = NULL;
	}

        // destroy all active sensors
        g_list_foreach(sensors_applet->active_sensors,
                       (GFunc)active_sensor_destroy,
                       NULL);

	if (sensors_applet->sensors != NULL) {
		gtk_tree_store_clear(sensors_applet->sensors);
	}

	gtk_widget_destroy(GTK_WIDGET(sensors_applet->applet));

	g_free(sensors_applet);
	return;
}

#if !GTK_CHECK_VERSION (3, 0, 0)
static void change_background_cb(MatePanelApplet *applet, 
				 MatePanelAppletBackgroundType type,
				 GdkColor *color, 
				 GdkPixmap *pixmap, 
				 gpointer *data) {
	GtkRcStyle *rc_style;
	GtkStyle *style;

        g_debug("change-background occurred");

	/* reset style */
	gtk_widget_set_style(GTK_WIDGET(applet), NULL);
	rc_style = gtk_rc_style_new();
	gtk_widget_modify_style(GTK_WIDGET(applet), rc_style);
	gtk_rc_style_unref(rc_style);

	switch(type) {
	case PANEL_COLOR_BACKGROUND:
		gtk_widget_modify_bg(GTK_WIDGET(applet),
				     GTK_STATE_NORMAL, color);
		break;

	case PANEL_PIXMAP_BACKGROUND:
		style = gtk_style_copy(GTK_WIDGET(applet)->style);
		if (style->bg_pixmap[GTK_STATE_NORMAL]) {
			g_object_unref(style->bg_pixmap[GTK_STATE_NORMAL]);
		}
		style->bg_pixmap[GTK_STATE_NORMAL] = g_object_ref(pixmap);
		gtk_widget_set_style(GTK_WIDGET(applet), style);
		g_object_unref(style);
		break;

	case PANEL_NO_BACKGROUND:
		/* fall through */
	default:
		break;
	}
}
#endif

static void change_orient_cb (MatePanelApplet *applet, 
                              MatePanelAppletOrient orient, 
                              gpointer data) {
        SensorsApplet *sensors_applet;
        sensors_applet = (SensorsApplet *)data;

        sensors_applet_display_layout_changed(sensors_applet);
}

static void size_allocate_cb(MatePanelApplet *applet, 
                             GtkAllocation *allocation, 
                             gpointer data) {
        SensorsApplet *sensors_applet;
        MatePanelAppletOrient orient;

        g_debug("size-allocate occurred");
        sensors_applet = (SensorsApplet *)data;
        orient = mate_panel_applet_get_orient(sensors_applet->applet);
        
        if ((orient == MATE_PANEL_APPLET_ORIENT_LEFT) || 
            (orient == MATE_PANEL_APPLET_ORIENT_RIGHT)) {
                if (sensors_applet->size == allocation->width)
                        return;
                sensors_applet->size = allocation->width;
        } else {
                if (sensors_applet->size == allocation->height)
                        return;
            sensors_applet->size = allocation->height;
        }
        /* update if new value */
        sensors_applet_graph_size_changed(sensors_applet);
        sensors_applet_display_layout_changed(sensors_applet);
}

static void style_set_cb(GtkWidget *widget,
                         GtkStyle *old_style,
                         gpointer data) {

        /* update all icons in the sensors tree and update all active
         * sensors */
	GtkTreeIter interfaces_iter, sensors_iter;
        GtkTreePath *path;
	gboolean not_end_of_interfaces = TRUE, not_end_of_sensors = TRUE;
        IconType icon_type;
        GdkPixbuf *new_icon;
        gboolean enabled;
        SensorsApplet *sensors_applet;
        DisplayMode display_mode;

        sensors_applet = (SensorsApplet *)data;

        g_debug("set-style occurred");

        display_mode = g_settings_get_int (sensors_applet->settings, DISPLAY_MODE);
        if (sensors_applet->sensors) {
                for (gtk_tree_model_get_iter_first(GTK_TREE_MODEL(sensors_applet->sensors), &interfaces_iter); not_end_of_interfaces; not_end_of_interfaces = gtk_tree_model_iter_next(GTK_TREE_MODEL(sensors_applet->sensors), &interfaces_iter)) {
                        
                        /* reset sensors sentinel */
                        not_end_of_sensors = TRUE;
                        
                        for (gtk_tree_model_iter_children(GTK_TREE_MODEL(sensors_applet->sensors), &sensors_iter, &interfaces_iter); not_end_of_sensors; not_end_of_sensors = gtk_tree_model_iter_next(GTK_TREE_MODEL(sensors_applet->sensors), &sensors_iter)) {
                                gtk_tree_model_get(GTK_TREE_MODEL(sensors_applet->sensors), 
                                                   &sensors_iter,
                                                   ENABLE_COLUMN, &enabled,
                                                   ICON_TYPE_COLUMN, &icon_type,
                                                   -1);
                                /* update icons */
                                new_icon = sensors_applet_load_icon(icon_type);
                                
                                gtk_tree_store_set(sensors_applet->sensors,
                                                   &sensors_iter,
                                                   ICON_PIXBUF_COLUMN, new_icon,
                                                   -1);
                                g_object_unref(new_icon);

                                /* update icons only if currently being
                                 * displayed */
                                if (enabled &&         
                                    (display_mode == DISPLAY_ICON || 
                                     display_mode == DISPLAY_ICON_WITH_VALUE)) {
                                        path = gtk_tree_model_get_path(GTK_TREE_MODEL(sensors_applet->sensors), 
                                                                       &sensors_iter);
                                        sensors_applet_icon_changed(sensors_applet,
                                                                    path);
                                        gtk_tree_path_free(path);
                                }
                        }
                }
                /* now update layout as size may have changed */
                sensors_applet_display_layout_changed(sensors_applet);
            }
            
}

static const GtkActionEntry sensors_applet_menu_actions[] = {
	{ "Preferences", GTK_STOCK_PROPERTIES, N_("_Preferences"),
		NULL, NULL,
		G_CALLBACK(prefs_cb) },
	{ "Help", GTK_STOCK_HELP, N_("_Help"),
		NULL, NULL,
		G_CALLBACK(help_cb) },
	{ "About", GTK_STOCK_ABOUT, N_("_About"),
		NULL, NULL,
		G_CALLBACK(about_cb) }
};

#ifdef HAVE_LIBNOTIFY
static void notif_closed_cb(NotifyNotification *notification,
                            SensorsApplet *sensors_applet) 
{
        g_assert(sensors_applet);
        
        sensors_applet->notification = NULL;
}
#endif // HAVE_LIBNOTIFY

void sensors_applet_notify_active_sensor(ActiveSensor *active_sensor, NotifType notif_type) {
#ifdef HAVE_LIBNOTIFY
 
        SensorsApplet *sensors_applet;
        gchar *summary, *message;
        gint timeout_msecs;
        gchar *sensor_label;
        gchar *sensor_path;
        SensorType sensor_type;
        TemperatureScale temp_scale;
        GtkTreeIter iter;
        GtkTreePath *path;
        const gchar *unit_type = NULL;
        const gchar *unit_type_title = NULL;
        const gchar *relation = NULL;
        const gchar *limit_type = NULL;
        const gchar *units = NULL;
        gdouble limit_value;
        
        sensors_applet = active_sensor->sensors_applet;

        if (!g_settings_get_boolean (sensors_applet->settings, DISPLAY_NOTIFICATIONS)) {
                g_debug("Wanted to display notification, but user has disabled them");
                return;
        }

        path = gtk_tree_row_reference_get_path(active_sensor->sensor_row);
        if (gtk_tree_model_get_iter(GTK_TREE_MODEL(sensors_applet->sensors), 
                                    &iter, path)) {
                gtk_tree_model_get(GTK_TREE_MODEL(sensors_applet->sensors), &iter,
                                   LABEL_COLUMN, &sensor_label,
                                   PATH_COLUMN, &sensor_path,
                                   SENSOR_TYPE_COLUMN, &sensor_type,
                                   -1);
        } else {
                g_warning("Error getting data from tree for notification...");
                gtk_tree_path_free(path);
                return;
        }
        gtk_tree_path_free(path);
        
        // do different stuff for different notif types
        switch (notif_type) {
        case LOW_ALARM: // fall thru
        case HIGH_ALARM:
                if (active_sensor->sensor_values[0] <= active_sensor->sensor_low_value &&
                    notif_type == LOW_ALARM) {
                        relation = _("is very low");
                        limit_type = _("lower limit");
                        limit_value = active_sensor->sensor_low_value;
                } else if (active_sensor->sensor_values[0] >= active_sensor->sensor_high_value &&
                           notif_type == HIGH_ALARM) {
                        /* assume high alarm condition */
                        relation = _("is very high");
                        limit_type = _("upper limit");
                        limit_value = active_sensor->sensor_high_value;
                } else {
                        g_warning("Alarm notify called when no alarm condition!");
                        g_free(sensor_path);
                        g_free(sensor_label);
                        return;
                }
                
                switch ((SensorType)sensor_type) {
                case TEMP_SENSOR:
                        unit_type_title = _("Temperature");
                        unit_type = _("temperature");
                        temp_scale = (TemperatureScale) g_settings_get_int (active_sensor->sensors_applet->settings, TEMPERATURE_SCALE);
                        
                        switch (temp_scale) {
                        case CELSIUS:
                                units = UNITS_CELSIUS;
                                break;
                        case FAHRENHEIT:
                                units = UNITS_FAHRENHEIT;
                                break;
                        case KELVIN:
                                units = UNITS_KELVIN;
                                break;
                        default:
                                units = NULL;
                        }
                        
                        break;
                case VOLTAGE_SENSOR:
                        unit_type_title = _("Voltage");
                        unit_type = _("voltage");
                        units = UNITS_VOLTAGE;
                break;
                case FAN_SENSOR:
                        unit_type_title = _("Fan Speed");
                        unit_type = _("fan speed");
                        units = UNITS_RPM;
                        break;
                case CURRENT_SENSOR:
                        unit_type_title = _("Current");
                        unit_type = _("current");
                        units = UNITS_CURRENT;
                        break;
                }
                
                timeout_msecs = (active_sensor->alarm_timeout ? MIN(DEFAULT_NOTIFY_TIMEOUT, (active_sensor->alarm_timeout * 1000)) : DEFAULT_NOTIFY_TIMEOUT);
                
                summary = g_strdup_printf("%s %s %s", sensor_label, unit_type_title, _("Alarm"));
                message = g_strdup_printf("%s %s %s (%s %2.0f%s)", sensor_label, unit_type, 
                                          relation, limit_type, limit_value, units);  
                break;
                
        case SENSOR_INTERFACE_ERROR:
                summary = g_strdup_printf(_("Error updating sensor %s"), sensor_label);
                message = g_strdup_printf(_("An error occurred while trying to update the value of the sensor %s located at %s."), sensor_label, sensor_path);
                timeout_msecs = g_settings_get_int (active_sensor->sensors_applet->settings, TIMEOUT);
                
                break;
                
        default:
                g_assert_not_reached();
        }
        
        active_sensor_libnotify_notify(active_sensor,
                                       notif_type,
                                       summary,
                                       message,
                                       GTK_STOCK_DIALOG_WARNING,
                                       timeout_msecs);
        
        g_free(sensor_path);
        g_free(sensor_label);
        g_free(summary);
        g_free(message);
#endif
}

void sensors_applet_notify_end(ActiveSensor *active_sensor, 
                               NotifType notif_type) {
#ifdef HAVE_LIBNOTIFY
        active_sensor_libnotify_notify_end(active_sensor, notif_type);
#endif
}

#ifdef HAVE_LIBNOTIFY
static void sensors_applet_notify_end_all_gfunc(ActiveSensor *active_sensor,
                                                gpointer data) {
        active_sensor_libnotify_notify_end(active_sensor, LOW_ALARM);
        active_sensor_libnotify_notify_end(active_sensor, HIGH_ALARM);
}
#endif

void sensors_applet_notify_end_all(SensorsApplet *sensors_applet) {
#ifdef HAVE_LIBNOTIFY
        g_list_foreach(sensors_applet->active_sensors,
                       (GFunc)sensors_applet_notify_end_all_gfunc,
                       NULL);
#endif
}

/* internal helper functions for updating display etc*/


/* should be called as a g_container_foreach at the start of
 * pack_display if ythe table already exists to remove but keep alive
 * all children of the table before repacking it */
static void sensors_applet_pack_display_empty_table_cb(GtkWidget *widget,
						   gpointer data) {
	GtkContainer *container;

        container = GTK_CONTAINER(data);

	/* ref then remove widget */
	g_object_ref(widget);
	gtk_container_remove(container, widget);
}

/* should be called as a g_container_foreach at the end of
 * pack_display to unref any of the old children that we have readdded
 * to the table to stop reference creep from the g_object_ref called
 * on each child at the start of pack labels */
static void sensors_applet_pack_display_cleanup_refs_cb(GtkWidget *widget,
							gpointer data) {
						  
	GList *old_children;

        old_children = (GList *)data;
	if (g_list_find(old_children, widget)) {
		g_object_unref(widget);
	}
}
						 
static void sensors_applet_pack_display(SensorsApplet *sensors_applet) {
	/* note the if () around each widget is to ensure we only
	 * operate on those that actually exist */
	GtkLabel *no_sensors_enabled_label = NULL;
	gint num_active_sensors = 0, num_sensors_per_group, rows, cols, i, j;
	GList *old_table_children = NULL;

	GList *current_sensor;

	DisplayMode display_mode;
        LayoutMode layout_mode;

        gboolean horizontal;
        gint label_width, icon_width, value_width;
        gint label_height, icon_height, value_height;
        
        GtkRequisition req;

        ActiveSensor *first_sensor;

        /* it is possible that there could be no active sensors so
         * handle that case first - make sure we dont do a NULL
         * pointer access first though */
        if (sensors_applet->active_sensors == NULL || 
            g_list_length(sensors_applet->active_sensors) == 0) {
                g_debug("no active sensors to pack in table");
                no_sensors_enabled_label = g_object_new(GTK_TYPE_LABEL,
                                                        "label", _("No sensors enabled!"),
                                                        NULL);

                if (sensors_applet->table == NULL) {
                        /* only need 1 row and 1 col */
                        sensors_applet->table = gtk_table_new(1, 1, FALSE);
                        gtk_table_set_col_spacings(GTK_TABLE(sensors_applet->table), COLUMN_SPACING);
                        gtk_table_set_row_spacings(GTK_TABLE(sensors_applet->table), ROW_SPACING);
                        /* add table to applet */
                        gtk_container_add(GTK_CONTAINER(sensors_applet->applet), sensors_applet->table);
                        
                } else {
                        /* destroy existing widgets - could be an
                         * existing version of no sensors label - okay
                         * to just add again though if destory fist */
                        g_debug("destorying any existing widgets in container");
                        gtk_container_foreach(GTK_CONTAINER(sensors_applet->table),
                                              (GtkCallback)gtk_widget_destroy,
                                              NULL);
                        /* make sure only 1x1 table */
                        gtk_table_resize(GTK_TABLE(sensors_applet->table),
                                         1, 1);
                }
                g_debug("packing no sensors enabled label");
                gtk_table_attach_defaults(GTK_TABLE(sensors_applet->table),
                                          GTK_WIDGET(no_sensors_enabled_label),
                                          0, 1,
                                          0, 1);
                gtk_widget_show_all(GTK_WIDGET(sensors_applet->applet));
                return;
                
	} 
        /* otherwise can acess active_sensors without any worries */
	num_active_sensors = g_list_length(sensors_applet->active_sensors);

	display_mode = (DisplayMode) g_settings_get_int (sensors_applet->settings, DISPLAY_MODE);
	layout_mode = (LayoutMode) g_settings_get_int (sensors_applet->settings, LAYOUT_MODE);


        horizontal = (((mate_panel_applet_get_orient(sensors_applet->applet) == MATE_PANEL_APPLET_ORIENT_UP) || 
                      (mate_panel_applet_get_orient(sensors_applet->applet) == MATE_PANEL_APPLET_ORIENT_DOWN)));

        /* figure out num rows / cols by how high / wide sensors
         * labels / icons are and how much size we have to put them
         * in */

        /* get the first active sensor */
        first_sensor = (ActiveSensor *)sensors_applet->active_sensors->data;


        switch (display_mode) {
        case DISPLAY_VALUE:
                gtk_widget_size_request(GTK_WIDGET(first_sensor->value),
                                        &req);
/* FIXME, this can be done better somewhere for cairo */
#if GTK_CHECK_VERSION (3, 0, 0)
                value_width = req.width + COLUMN_SPACING + 10;
                value_height = req.height + ROW_SPACING + 10;
#else
                value_width = req.width + COLUMN_SPACING;
                value_height = req.height + ROW_SPACING;
#endif

                /* make sure all widths and heights are non zero,
                 * otherwise will get a divide by zero exception below
                 * - is a non critical error since can happen when
                 * elements first added to list, so simply return - is
                 * not a programming error */
                if (value_width == 0 && value_height == 0) {
                        return;
                }

                num_sensors_per_group = (sensors_applet->size / 
                                         (horizontal ? value_height : 
                                          value_width));
                break;

        case DISPLAY_LABEL_WITH_VALUE:
                /* even though we end up packing the event boxes into the
                 * panel, these dont give back request sizes, so need to ask
                 * widgets directly */
                gtk_widget_size_request(GTK_WIDGET(first_sensor->value),
                                        &req);
/* FIXME, this can be done better somewhere for cairo */
#if GTK_CHECK_VERSION (3, 0, 0)
                value_width = req.width + COLUMN_SPACING + 10;
                value_height = req.height + ROW_SPACING + 10;

                gtk_widget_size_request(GTK_WIDGET(first_sensor->label),
                                        &req);
                label_width = req.width + COLUMN_SPACING + 10;
                label_height = req.height + ROW_SPACING + 10;
#else
                value_width = req.width + COLUMN_SPACING;
                value_height = req.height + ROW_SPACING;

                gtk_widget_size_request(GTK_WIDGET(first_sensor->label),
                                        &req);
                label_width = req.width + COLUMN_SPACING;
                label_height = req.height + ROW_SPACING;
#endif
        
                /* make sure all widths and heights are non zero, otherwise
                 * will get a divide by zero exception below 
                 * - is a non critical error since can happen when
                 * elements first added to list, so simply return - is
                 * not a programming error */
                if (!(label_width && label_height &&
                      value_width && value_height)) {
                        return;
                }

                switch (layout_mode) {
                case VALUE_BESIDE_LABEL:
                        num_sensors_per_group = (sensors_applet->size / 
                                                 (horizontal ? MAX(label_height, value_height) : 
                                                  (label_width + value_width)));
                        break;
                case VALUE_BELOW_LABEL:
                        num_sensors_per_group = (sensors_applet->size / 
                                                 (horizontal ? (label_height + value_height) : 
                                                  MAX(label_width, value_width)));


                        break;
                }
                break;

        case DISPLAY_ICON_WITH_VALUE:
                gtk_widget_size_request(GTK_WIDGET(first_sensor->value),
                                        &req);
/* FIXME, this can be done better somewhere for cairo */
#if GTK_CHECK_VERSION (3, 0, 0)
                value_width = req.width + COLUMN_SPACING +10;
                value_height = req.height + ROW_SPACING + 10;

                gtk_widget_size_request(GTK_WIDGET(first_sensor->icon),
                                        &req);
                icon_width = req.width + COLUMN_SPACING + 10;
                icon_height = req.height + ROW_SPACING + 10;
#else
                value_width = req.width + COLUMN_SPACING;
                value_height = req.height + ROW_SPACING;

                gtk_widget_size_request(GTK_WIDGET(first_sensor->icon),
                                        &req);
                icon_width = req.width + COLUMN_SPACING;
                icon_height = req.height + ROW_SPACING;
#endif
                
                if (!(icon_width && icon_height &&
                      value_width && value_height)) {
                        return;
                }
                
                switch (layout_mode) {
                case VALUE_BESIDE_LABEL:
                        num_sensors_per_group = (sensors_applet->size / 
                                                 (horizontal ? MAX(icon_height, value_height) : 
                                                  (icon_width + value_width)));
                        break;
                case VALUE_BELOW_LABEL:
                        num_sensors_per_group = (sensors_applet->size / 
                                                 (horizontal ? (icon_height + value_height) : 
                                                  MAX(icon_width, value_width)));


                        break;
                }
                break;

        case DISPLAY_ICON:
                gtk_widget_size_request(GTK_WIDGET(first_sensor->icon),
                                        &req);
/* FIXME, this can be done better somewhere for cairo */
#if GTK_CHECK_VERSION (3, 0, 0)
                icon_width = req.width + COLUMN_SPACING + 10;
                icon_height = req.height + ROW_SPACING + 10;
#else
                icon_width = req.width + COLUMN_SPACING;
                icon_height = req.height + ROW_SPACING;
#endif
                if (!(icon_width && icon_height)) {
                        return;
                }

                num_sensors_per_group = (sensors_applet->size / 
                                         (horizontal ? icon_height : 
                                          icon_width));
                break;

        case DISPLAY_GRAPH:
                /* only show graphs in a line like System Monitor
                 * applet */
                num_sensors_per_group = 1;
                break;
        }
        /* ensure always atleast 1 sensor per group */
        if (num_sensors_per_group < 1) {
                /* force a better layout */
                if (horizontal && layout_mode == VALUE_BELOW_LABEL) {
                        layout_mode = VALUE_BESIDE_LABEL;
                } else if (!horizontal && layout_mode == VALUE_BESIDE_LABEL) {
                        layout_mode = VALUE_BELOW_LABEL;
                }
                num_sensors_per_group = 1;
        }

	if (horizontal) {
		/* if oriented horizontally, want as many
		   sensors per column as user has defined, then
		   enough columns to hold all the widgets */
		rows = num_sensors_per_group;
		cols = num_active_sensors / num_sensors_per_group;
		while (rows * cols < num_active_sensors || cols == 0) {
			cols++;
		}
		
	} else {
		/* if oriented vertically, want as many
		   sensors per row as user has defined, then
		   enough rows to hold all the widgets*/
		cols = num_sensors_per_group;
		rows = num_active_sensors / num_sensors_per_group;
		while (rows * cols < num_active_sensors || rows == 0) {
			rows++;
		}
		
	}

	/* if displaying labels / icons and values need to modify
	   number of rows / colums to accomodate this */
	 if (display_mode == DISPLAY_LABEL_WITH_VALUE || 
             display_mode == DISPLAY_ICON_WITH_VALUE) {
		 if (layout_mode == VALUE_BESIDE_LABEL) {
			 /* to display labels next to values need twice
			    as many columns */
			 cols *= 2;
		 } else {
			 /* to display labels above values, we need
			  * twice as many rows as without */
			 rows *= 2;
		 }
	 }	 

	if (sensors_applet->table == NULL) {
		/* create table and add to applet */
		sensors_applet->table = gtk_table_new(rows, cols, FALSE);
		gtk_table_set_col_spacings(GTK_TABLE(sensors_applet->table), COLUMN_SPACING);
		gtk_table_set_row_spacings(GTK_TABLE(sensors_applet->table), ROW_SPACING);
		gtk_container_add(GTK_CONTAINER(sensors_applet->applet), sensors_applet->table);
	} else {
		/* remove all children if table already exists so we can start
		 * again */
		/* save a list of the old children for later */
		old_table_children = gtk_container_get_children(GTK_CONTAINER(sensors_applet->table));

		gtk_container_foreach(GTK_CONTAINER(sensors_applet->table),
				      sensors_applet_pack_display_empty_table_cb,
				      sensors_applet->table);

		/* then resize table */
		gtk_table_resize(GTK_TABLE(sensors_applet->table), rows, cols);
	}
              
              /* pack icons / labels and values into table */
              current_sensor = sensors_applet->active_sensors;

	/* if showing labels / icons and values, need to pack labels /
         * icons these first */
	if (display_mode == DISPLAY_ICON_WITH_VALUE || 
            display_mode == DISPLAY_LABEL_WITH_VALUE) {
		/* loop through columns */
		for (i = 0; current_sensor != NULL && i < cols; /* increments depends on how we lay them out - see below */) {
		
			/* loop through rows in a column */
			for (j = 0; current_sensor && j < rows; /* see bottom of for loop*/) {
				/* attach label / icon at this point */
				if (display_mode == DISPLAY_ICON_WITH_VALUE) {
					if (((ActiveSensor *)(current_sensor->data))->icon) {
						gtk_table_attach_defaults(GTK_TABLE(sensors_applet->table),
                                                                          ((ActiveSensor *)(current_sensor->data))->icon,
									  i, i + 1,
									  j, j + 1);
					}
				} else {
					if (((ActiveSensor *)(current_sensor->data))->label) {
						gtk_table_attach_defaults(GTK_TABLE(sensors_applet->table),
									  ((ActiveSensor *)(current_sensor->data))->label,
                                                                          i, i + 1,
									  j, j + 1);
					}				
				}
				/* now attach sensor value to either
				   row below or column next to */
				if (layout_mode == VALUE_BESIDE_LABEL) { 
					/* left align labels */
					if (((ActiveSensor *)(current_sensor->data))->icon) {
						gtk_misc_set_alignment(GTK_MISC(((ActiveSensor *)(current_sensor->data))->icon), 0.0, 0.5);
					}
					if (((ActiveSensor *)(current_sensor->data))->label) {
						gtk_misc_set_alignment(GTK_MISC(((ActiveSensor *)(current_sensor->data))->label), 0.0, 0.5); 	 
					}
					if (((ActiveSensor *)(current_sensor->data))->value) {
						gtk_misc_set_alignment(GTK_MISC(((ActiveSensor *)(current_sensor->data))->value), 0.0, 0.5);
					}
 

					 /* place value next to label */
					if (((ActiveSensor *)(current_sensor->data))->value) {
						gtk_table_attach_defaults(GTK_TABLE(sensors_applet->table),
									  ((ActiveSensor *)(current_sensor->data))->value,
									  i + 1, i + 2,
									  j, j + 1);
					}
					j++;
				} else { /* place value below label */
					/* center align labels */ 	 
					if (((ActiveSensor *)(current_sensor->data))->icon) {
						gtk_misc_set_alignment(GTK_MISC(((ActiveSensor *)(current_sensor->data))->icon), 0.5, 0.5);
					}
					if (((ActiveSensor *)(current_sensor->data))->label) {
						gtk_misc_set_alignment(GTK_MISC(((ActiveSensor *)(current_sensor->data))->label), 0.5, 0.5);
					}
					if (((ActiveSensor *)(current_sensor->data))->value) {
						gtk_misc_set_alignment(GTK_MISC(((ActiveSensor *)(current_sensor->data))->value), 0.5, 0.5); 	 
					}
 
					if (((ActiveSensor *)(current_sensor->data))->value) {
						gtk_table_attach_defaults(GTK_TABLE(sensors_applet->table),
									  ((ActiveSensor *)(current_sensor->data))->value,
									  i, i + 1,
									  j + 1, j + 2);
					}
					j += 2;
				}
				current_sensor = g_list_next(current_sensor);

			} /* end row loop */
			/* now increment column index as needed */
			if (layout_mode == VALUE_BESIDE_LABEL) { /* place value next to label */
				i += 2;
			} else {
				i++;
			}
			
			
		} /* end column loop	*/

		
	} else { /* not showing labels and icons with values, so just
                  * pack either only icons or values */
		for (i = 0; current_sensor != NULL && i < cols; ++i) {
			for (j = 0; current_sensor!= NULL && j < rows; ++j) {
                                if (display_mode == DISPLAY_VALUE) {
                                        
                                        if (((ActiveSensor *)(current_sensor->data))->value) {
                                                gtk_table_attach_defaults(GTK_TABLE(sensors_applet->table),
                                                                          ((ActiveSensor *)(current_sensor->data))->value,
                                                                          i, i + 1,
                                                                          j, j + 1);
                                        }
                                } else if (display_mode == DISPLAY_ICON) {
                                        if (((ActiveSensor *)(current_sensor->data))->value) {
                                                gtk_table_attach_defaults(GTK_TABLE(sensors_applet->table),
                                                                          ((ActiveSensor *)(current_sensor->data))->icon,
                                                                          i, i + 1,
                                                                          j, j + 1);
                                        }
                                } else if (display_mode == DISPLAY_GRAPH) {
                                        if (((ActiveSensor *)(current_sensor->data))->graph) {
                                                gtk_table_attach_defaults(GTK_TABLE(sensors_applet->table),
                                                                          ((ActiveSensor *)(current_sensor->data))->graph_frame,
                                                                          i, i + 1,
                                                                          j, j + 1);
                                        }
                                }


				current_sensor = g_list_next(current_sensor);
			}
		}
		
	}
	if (old_table_children != NULL) {
		gtk_container_foreach(GTK_CONTAINER(sensors_applet->table),
				      sensors_applet_pack_display_cleanup_refs_cb,
				      old_table_children);
		g_list_free(old_table_children);
	}
	gtk_widget_show_all(GTK_WIDGET(sensors_applet->applet));

} 	    

/* must unref when done with returned pixbuf */
GdkPixbuf *sensors_applet_load_icon(IconType icon_type) {
        GtkIconTheme *icon_theme;
        GdkPixbuf *icon = NULL;
        GError *error = NULL;

	/* try to load the icon */

        /* not allowed to unref or ref icon_theme once we have it */
        icon_theme = gtk_icon_theme_get_default();
        icon = gtk_icon_theme_load_icon(icon_theme,
                                        stock_icons[icon_type],
                                        DEFAULT_ICON_SIZE,
                                        GTK_ICON_LOOKUP_USE_BUILTIN,
                                        &error);
	if (error) {
                g_warning ("Could not load icon: %s", error->message);
                g_error_free(error);
                error = NULL;
                
                /* try again with default icon */
                icon = gtk_icon_theme_load_icon(icon_theme,
                                                GTK_STOCK_MISSING_IMAGE,
                                                DEFAULT_ICON_SIZE,
                                                GTK_ICON_LOOKUP_USE_BUILTIN,
                                                &error);
                if (error) {
                        /* this will quit sensors-applet but
                         * it is a pretty major error so may
                         * as well */
                        
                        g_error("Could not load GTK_STOCK_MISSING_IMAGE - major error!!!: %s", error->message);
                        
                        g_error_free(error);
                        error = NULL;
                }
                         
        }
        return icon;
}

gboolean sensors_applet_add_sensor(SensorsApplet *sensors_applet,
                                   const gchar *path, 
                                   const gchar *id, 
                                   const gchar *label, 
                                   const gchar *interface, 
                                   SensorType type, 
                                   gboolean enable,
                                   gdouble low_value,
                                   gdouble high_value,
                                   gboolean alarm_enable,
                                   const gchar *low_alarm_command,
                                   const gchar *high_alarm_command,
                                   gint alarm_timeout,
                                   gdouble multiplier,
                                   gdouble offset,
                                   IconType icon_type,
                                   const gchar *graph_color) {
        
					       
	GtkTreeIter interfaces_iter, sensors_iter;
	gboolean not_empty_tree;

        gchar *node_interface;
	gboolean not_end_of_interfaces = TRUE, interface_exists = FALSE;
	gboolean not_end_of_sensors = TRUE;
	gchar *sensor_id;
        gchar *sensor_path;
        SensorType sensor_type;
	GdkPixbuf *icon;
	GtkTreePath *tree_path;

	g_assert(sensors_applet);

	/* assume tree is not empty */
	not_empty_tree = TRUE;


	if (NULL == sensors_applet->sensors) {

		sensors_applet->sensors = gtk_tree_store_new(N_COLUMNS, 
							     G_TYPE_STRING, /* path */
							     G_TYPE_STRING, /* id */
							     G_TYPE_STRING, /* label */
							     G_TYPE_STRING, /* interface */
							     G_TYPE_UINT, /* sensor
									   * type */
							     G_TYPE_BOOLEAN, /* enable */
							     G_TYPE_BOOLEAN, /* visible */
							     G_TYPE_DOUBLE, /* low value */
							     G_TYPE_DOUBLE, /* high type */
							     G_TYPE_BOOLEAN, /* alarm enable */
							     G_TYPE_STRING, /* low alarm command */ 
							     G_TYPE_STRING, /* high alarm command */ 
							     G_TYPE_UINT, /* alarm timeout */
							     G_TYPE_DOUBLE, /* multiplier */
							     G_TYPE_DOUBLE, /* offset */
							     G_TYPE_UINT, /* icon type */
							     GDK_TYPE_PIXBUF, /* icon pixbuf */
                                                             G_TYPE_STRING); /* graph color */
		      
		 
		g_debug("Sensor tree created.");

		/* we know tree is actually empty since we just created it */
		not_empty_tree = FALSE;
	}
	
	/* search sensor tree for the parent interface to place this
	 * sensor under */
	for (not_empty_tree = gtk_tree_model_get_iter_first(GTK_TREE_MODEL(sensors_applet->sensors), &interfaces_iter); not_empty_tree && not_end_of_interfaces && !interface_exists; not_end_of_interfaces = gtk_tree_model_iter_next(GTK_TREE_MODEL(sensors_applet->sensors), &interfaces_iter)) {
		gtk_tree_model_get(GTK_TREE_MODEL(sensors_applet->sensors), &interfaces_iter,
				   INTERFACE_COLUMN, &node_interface,
				   -1);
		if (g_ascii_strcasecmp(interface, node_interface) == 0) {
			/* found interface in tree */
			interface_exists = TRUE;
                        
			/* now see if this actual sensor already
			 * exists within this interface - don't want
			 * to add duplicates */
			/* see if have children */
			for (not_end_of_sensors = gtk_tree_model_iter_children(GTK_TREE_MODEL(sensors_applet->sensors), &sensors_iter,  &interfaces_iter); not_end_of_sensors; not_end_of_sensors = gtk_tree_model_iter_next(GTK_TREE_MODEL(sensors_applet->sensors), &sensors_iter)) {
				gtk_tree_model_get(GTK_TREE_MODEL(sensors_applet->sensors), &sensors_iter,
						   PATH_COLUMN, &sensor_path,
						   ID_COLUMN, &sensor_id,
						   SENSOR_TYPE_COLUMN, &sensor_type,
						   -1);
				if (g_ascii_strcasecmp(sensor_id, id) == 0 &&
                                    g_ascii_strcasecmp(sensor_path, path) == 0  &&
                                    sensor_type == type) {
					/* sensor already exists so
					 * dont add a second time */
					g_debug("sensor with path: %s, id: %s already exists in tree, not adding a second time", sensor_path, sensor_id);
					g_free(sensor_id);
					g_free(sensor_path);
                                        g_free(node_interface);
					return FALSE;
				}
				g_free(sensor_id);
                                g_free(sensor_path);
			}
                        g_free(node_interface);
			break;
		}
                g_free(node_interface);               
        }
                


	if (!interface_exists) {
                /* add to required plugins hash table so we ensure this
                   plugin stays loaded to make sure we have a get sensor
                   value function if possible */
                g_hash_table_insert(sensors_applet->required_plugins,
                                    g_strdup(interface),
                                    GINT_TO_POINTER(TRUE));
                g_debug("added interface %s to required plugins", interface);

		/* wasn't able to find interface root node so create it */
		gtk_tree_store_append(sensors_applet->sensors,
				      &interfaces_iter,
				      NULL);
		
		gtk_tree_store_set(sensors_applet->sensors,
				   &interfaces_iter,
				   ID_COLUMN, interface,
				   INTERFACE_COLUMN, interface,
				   VISIBLE_COLUMN, FALSE,
				   -1);
                g_debug("Added sensor interface %s to tree", interface);
	}

	
	/* then add sensor as a child under interface node - ie assume
	 * we either found it or created it - the inteface node that
	 * is */

	/* for now just add sensors all in a single list */
	gtk_tree_store_append(sensors_applet->sensors,
			      &sensors_iter,
			      &interfaces_iter);
	
	/* if sensor is already in settings, load values from there */
	gchar *applet_path = mate_panel_applet_get_preferences_path (sensors_applet->applet);
	gchar *settings_path = g_strdup_printf ("%s%s/",
				applet_path,
				sensors_applet_settings_get_unique_id (interface,
								       id,
								       path));
	GSettings *settings = g_settings_new_with_path ("org.mate.sensors-applet.sensor", settings_path);
	g_free (applet_path);
	g_free (settings_path);
	
	gchar *settings_id = g_settings_get_string (settings, ID);
	
	if (settings_id != NULL && settings_id[0] != '\0') {
		enable = g_settings_get_boolean (settings, ENABLED);
		icon = sensors_applet_load_icon(g_settings_get_int (settings, ICON_TYPE));
		gtk_tree_store_set(sensors_applet->sensors,
				   &sensors_iter,
				   PATH_COLUMN, g_settings_get_string (settings, PATH),
				   ID_COLUMN, settings_id,
				   LABEL_COLUMN, g_settings_get_string (settings, LABEL),
				   INTERFACE_COLUMN, g_settings_get_string (settings, INTERFACE),
				   SENSOR_TYPE_COLUMN, g_settings_get_int (settings, SENSOR_TYPE),
				   ENABLE_COLUMN, enable,
				   VISIBLE_COLUMN, TRUE,
				   LOW_VALUE_COLUMN, g_settings_get_double (settings, LOW_VALUE),
				   HIGH_VALUE_COLUMN, g_settings_get_double (settings, HIGH_VALUE),
				   ALARM_ENABLE_COLUMN, g_settings_get_boolean (settings, ALARM_ENABLED),
				   ALARM_TIMEOUT_COLUMN, g_settings_get_int (settings, ALARM_TIMEOUT),
				   LOW_ALARM_COMMAND_COLUMN, g_settings_get_string (settings, LOW_ALARM_COMMAND),
				   HIGH_ALARM_COMMAND_COLUMN, g_settings_get_string (settings, HIGH_ALARM_COMMAND),
				   MULTIPLIER_COLUMN, g_settings_get_double (settings, MULTIPLIER),
				   OFFSET_COLUMN, g_settings_get_double (settings, OFFSET),
				   ICON_TYPE_COLUMN, g_settings_get_int (settings, ICON_TYPE),
				   ICON_PIXBUF_COLUMN, icon,
				   GRAPH_COLOR_COLUMN, g_settings_get_string (settings, GRAPH_COLOR),
				   -1);
		g_free (settings_id);
	}
	else {
		icon = sensors_applet_load_icon(icon_type);
		gtk_tree_store_set(sensors_applet->sensors,
				   &sensors_iter,
				   PATH_COLUMN, path,
				   ID_COLUMN, id,
				   LABEL_COLUMN, label,
				   INTERFACE_COLUMN, interface,
				   SENSOR_TYPE_COLUMN, type,
				   ENABLE_COLUMN, enable,
				   VISIBLE_COLUMN, TRUE,
				   LOW_VALUE_COLUMN, low_value,
				   HIGH_VALUE_COLUMN, high_value,
				   ALARM_ENABLE_COLUMN, alarm_enable,
				   ALARM_TIMEOUT_COLUMN, alarm_timeout,
				   LOW_ALARM_COMMAND_COLUMN, low_alarm_command,
				   HIGH_ALARM_COMMAND_COLUMN, high_alarm_command,
				   MULTIPLIER_COLUMN, multiplier,
				   OFFSET_COLUMN, offset,
				   ICON_TYPE_COLUMN, icon_type,
				   ICON_PIXBUF_COLUMN, icon,
				   GRAPH_COLOR_COLUMN, graph_color,
				   -1);
	}
	g_object_unref (settings);
	g_debug("added sensor %s to tree", path);

	/* remove reference to icon as tree now has ref */
	g_object_unref(icon);

	/* create the active sensor */
	if (enable) {
		tree_path = gtk_tree_model_get_path(GTK_TREE_MODEL(sensors_applet->sensors), &sensors_iter);
		sensors_applet_sensor_enabled(sensors_applet, tree_path);
		gtk_tree_path_free(tree_path);
	}
        return TRUE;
}	


static ActiveSensor *sensors_applet_find_active_sensor(SensorsApplet *sensors_applet,
                                                       GtkTreePath *path) {
	GtkTreePath *sensor_tree_path;
	GList *current_sensor;
	
	for (current_sensor = sensors_applet->active_sensors; current_sensor != NULL; current_sensor = g_list_next(current_sensor)) {
		sensor_tree_path = gtk_tree_row_reference_get_path(((ActiveSensor *)(current_sensor->data))->sensor_row);

		if (gtk_tree_path_compare(path, sensor_tree_path) == 0) {
                        gtk_tree_path_free(sensor_tree_path);
			return ((ActiveSensor *)(current_sensor->data));
		}
                gtk_tree_path_free(sensor_tree_path);
	}
	return NULL;
}
	
	
/* path should be the full path to a file representing the sensor (eg
 * /dev/hda or /sys/devices/platform/i2c-0/0-0290/temp1_input) */
	
void sensors_applet_display_layout_changed(SensorsApplet *sensors_applet) {
        /* update sensors since will need to update icons / graphs etc
         * if weren't displayed before */
        GList *list = NULL;
        for (list = sensors_applet->active_sensors;
             list != NULL;
             list = list->next) {
                ActiveSensor *as = (ActiveSensor *)list->data;
                as->updated = FALSE;
        }
        sensors_applet_update_active_sensors(sensors_applet);
	sensors_applet_pack_display(sensors_applet);
}

void sensors_applet_alarm_off(SensorsApplet *sensors_applet,
                              GtkTreePath *path,
                              NotifType notif_type) {
	ActiveSensor *active_sensor;

	if ((active_sensor = sensors_applet_find_active_sensor(sensors_applet,
                                                               path)) != NULL) {
		active_sensor_alarm_off(active_sensor, notif_type);
	}
}
				
void sensors_applet_all_alarms_off(SensorsApplet *sensors_applet,
                                   GtkTreePath *path) {
        sensors_applet_alarm_off(sensors_applet, path, LOW_ALARM);
        sensors_applet_alarm_off(sensors_applet, path, HIGH_ALARM);
}


void sensors_applet_sensor_enabled(SensorsApplet *sensors_applet,
                                   GtkTreePath *path) {
	ActiveSensor *active_sensor;

	g_assert(sensors_applet);
	g_assert(path);

        active_sensor = active_sensor_new(sensors_applet,
                                          gtk_tree_row_reference_new(GTK_TREE_MODEL(sensors_applet->sensors), path));
        
        active_sensor_update(active_sensor, sensors_applet);
                                                                     
        /* keep list sorted */
	sensors_applet->active_sensors = g_list_insert_sorted(sensors_applet->active_sensors, 
                                                              active_sensor, 
                                                              (GCompareFunc)active_sensor_compare);
	
        sensors_applet_pack_display(sensors_applet);
}

void sensors_applet_reorder_sensors(SensorsApplet *sensors_applet) {
        sensors_applet->active_sensors = g_list_sort(sensors_applet->active_sensors, (GCompareFunc)active_sensor_compare);

	sensors_applet_pack_display(sensors_applet);
}
                                                     
void sensors_applet_sensor_disabled(SensorsApplet *sensors_applet,
                                    GtkTreePath *path) {

	ActiveSensor *active_sensor;

	g_assert(sensors_applet);
	g_assert(path);

	if ((active_sensor = sensors_applet_find_active_sensor(sensors_applet,
                                                               path)) != NULL) {
		g_debug("Destroying active sensor...");
		
		g_debug("-- removing from list...");
		sensors_applet->active_sensors = g_list_remove(sensors_applet->active_sensors,
			      active_sensor);
		g_debug("-- repacking display....");
		sensors_applet_pack_display(sensors_applet);
                
                active_sensor_destroy(active_sensor);
	}
}


void sensors_applet_update_sensor(SensorsApplet *sensors_applet,
                                  GtkTreePath *path) {
	ActiveSensor *active_sensor;

	g_assert(sensors_applet);
	g_assert(path);

	if ((active_sensor = sensors_applet_find_active_sensor(sensors_applet,
                                                               path)) != NULL) {
		active_sensor_update(active_sensor, 
				     sensors_applet);
	}
}
 
void sensors_applet_icon_changed(SensorsApplet *sensors_applet,
                                 GtkTreePath *path) {
	ActiveSensor *active_sensor;
	
	g_assert(sensors_applet);
	g_assert(path);
	
	if ((active_sensor = sensors_applet_find_active_sensor(sensors_applet,
                                                               path)) != NULL) {
		active_sensor_icon_changed(active_sensor,
					   sensors_applet);
	}
}

/**
 * Cycle thru ActiveSensors and update them all
 */
gboolean sensors_applet_update_active_sensors(SensorsApplet *sensors_applet) {
	g_assert(sensors_applet);
        
        if (sensors_applet->active_sensors) {
                g_list_foreach(sensors_applet->active_sensors,
                               (GFunc)active_sensor_update,
                               sensors_applet);
                return TRUE;
        }
        return FALSE;
}

/**
 * Cycle thru ActiveSensors and set new graph dimensions
 */
void sensors_applet_graph_size_changed(SensorsApplet *sensors_applet) {
	gint dimensions[2];
        gint graph_size;
	g_assert(sensors_applet);

        if (sensors_applet->active_sensors) {
                
                graph_size = g_settings_get_int (sensors_applet->settings, GRAPH_SIZE);
                if (mate_panel_applet_get_orient(sensors_applet->applet) == 
                    MATE_PANEL_APPLET_ORIENT_UP ||
                    mate_panel_applet_get_orient(sensors_applet->applet) == 
                    MATE_PANEL_APPLET_ORIENT_DOWN) {
                        /* is horizontal so set graph_size as width */
                        dimensions[0] = graph_size;
                        dimensions[1] = sensors_applet->size;
                } else {
                        dimensions[0] = sensors_applet->size;
                        dimensions[1] = graph_size;
                }                        

                g_list_foreach(sensors_applet->active_sensors,
                               (GFunc)active_sensor_update_graph_dimensions,
                               &dimensions);
        }
        
}

gdouble sensors_applet_convert_temperature(gdouble value, 
                                           TemperatureScale old, 
                                           TemperatureScale new) {

        switch (old) {
        case KELVIN:
                switch (new) {
                case CELSIUS:
                        value = value - 273.0;
                        break;
                case FAHRENHEIT:
                        value = (9.0 * (value - 273) / 5.0) + 32.0;
                        break;
                case KELVIN:
                        break;
                }
                break;
        case CELSIUS:
                switch (new) {
                case FAHRENHEIT:
                        value = (9.0 * value / 5.0) + 32.0;
                        break;
                case KELVIN:
                        value = value + 273.0;
                        break;
                case CELSIUS:
                        break;
                }
                break;

        case FAHRENHEIT:
                switch (new) {
                case CELSIUS: 
                        value = (5.0 * (value - 32.0) / 9.0);
                        break;
                case KELVIN:
                        value = (5.0 * (value - 32.0) / 9.0) + 273.0;
                        break;
                case FAHRENHEIT:
                        break;
                }
                break;
        }
        return value;
}

void sensors_applet_init(SensorsApplet *sensors_applet) {
	
        g_assert(sensors_applet);
	g_assert(sensors_applet->applet);

	GtkActionGroup *action_group;
	gchar *ui_path;

        /* plugin functions are stored as name -> get_value_function pairs so
         * use standard string functions on hash table */
        sensors_applet->plugins = g_hash_table_new(g_str_hash,
                                                      g_str_equal);

        sensors_applet->required_plugins = g_hash_table_new_full(g_str_hash,
                                                                 g_str_equal,
                                                                 g_free,
                                                                 NULL);
        
        /* initialise size */
        sensors_applet->size = DEFAULT_APPLET_SIZE;

        mate_panel_applet_set_flags(sensors_applet->applet, 
                               MATE_PANEL_APPLET_EXPAND_MINOR);

	g_signal_connect(sensors_applet->applet, "destroy",
			 G_CALLBACK(destroy_cb),
			 sensors_applet);

	/* init gsettings */
	sensors_applet->settings = mate_panel_applet_settings_new (sensors_applet->applet,
								   "org.mate.sensors-applet");

	/* now do any setup needed manually */
        sensors_applet_plugins_load_all(sensors_applet);        

        /* should have created sensors tree above, but if have
	   not was because we couldn't find any sensors */
	if (NULL == sensors_applet->sensors) {
		GtkWidget *label;	
		label = gtk_label_new(_("No sensors found!"));
		gtk_container_add(GTK_CONTAINER(sensors_applet->applet), label);
		gtk_widget_show_all(GTK_WIDGET(sensors_applet->applet));
		return;
	}
	
        /* only do menu and signal connections if sensors are found */
	action_group = gtk_action_group_new ("Sensors Applet Actions");
	gtk_action_group_set_translation_domain (action_group, GETTEXT_PACKAGE);
	gtk_action_group_add_actions (action_group,
		sensors_applet_menu_actions,
		G_N_ELEMENTS (sensors_applet_menu_actions),
		sensors_applet);
	ui_path = g_build_filename (UIDIR, SENSORS_APPLET_MENU_FILE, NULL);
	mate_panel_applet_setup_menu_from_file (sensors_applet->applet, ui_path, action_group);
	g_free (ui_path);
	g_object_unref (action_group);

	g_signal_connect(sensors_applet->applet, "style-set",
			 G_CALLBACK(style_set_cb),
			 sensors_applet);

#if !GTK_CHECK_VERSION (3, 0, 0)
	g_signal_connect(sensors_applet->applet, "change_background",
			 G_CALLBACK(change_background_cb), 
			 sensors_applet);
#endif

        g_signal_connect(G_OBJECT(sensors_applet->applet), "change_orient",
                          G_CALLBACK(change_orient_cb), 
                          sensors_applet);

        g_signal_connect(G_OBJECT(sensors_applet->applet), "size_allocate",
                          G_CALLBACK(size_allocate_cb), 
                          sensors_applet);



	sensors_applet_update_active_sensors(sensors_applet);
	sensors_applet_pack_display(sensors_applet);

	sensors_applet->timeout_id = g_timeout_add_seconds(g_settings_get_int(sensors_applet->settings, TIMEOUT) / 1000, 
                                                           (GSourceFunc)sensors_applet_update_active_sensors, 
                                                           sensors_applet);
	gtk_widget_show_all(GTK_WIDGET(sensors_applet->applet));
}