wacom: Implement g-c-c calibration functionality

Adds and handles callback from the "Calibrate" button.
When clicked, we get the current calibration and feed
it in to the calibration utility. After it completes
we get back a modified calibration and an indication
of success. If it was successful we apply the changes,
if not, we ignore the modifed calibration.

https://bugzilla.gnome.org/show_bug.cgi?id=657423

panels/wacom/calibrator/gui_gtk.c

@@ -408,4 +408,3 @@ run_gui(struct Calib *c,
 
    return success;
 }
-

panels/wacom/cc-wacom-page.c

@@ -24,6 +24,7 @@
 
 #include "cc-wacom-page.h"
 #include "cc-wacom-nav-button.h"
+#include "gui_gtk.h"
 #include <gtk/gtk.h>
 
 #include <string.h>
@@ -113,6 +114,114 @@ eraser_feel_value_changed_cb (GtkRange *range, gpointer user_data)
     set_pressurecurve (range, CC_WACOM_PAGE(user_data)->priv->eraser_settings);
 }
 
+static void
+get_calibration (gint      ** cal,
+                 gsize      * ncal,
+                 GSettings  * settings)
+{
+	GVariant *current = g_settings_get_value (settings, "area");
+	*cal = g_variant_get_fixed_array (current, ncal, sizeof (gint32));
+}
+
+static void
+set_calibration (gint      *cal,
+                 gsize      ncal,
+                 GSettings *settings)
+{
+	GVariant    *current; /* current calibration */
+	GVariant    *array;   /* new calibration */
+	GVariant   **tmp;
+	gsize        nvalues;
+	const gint  *values;
+	int          i;
+
+	current = g_settings_get_value (settings, "area");
+	values = g_variant_get_fixed_array (current, &nvalues, sizeof (gint32));
+	if ((ncal != 4) || (nvalues != 4))
+	{
+		g_warning("Unable set set device calibration property. Got %d items to put in %d slots; expected %d items.\n", ncal, nvalues, 4);
+		return;
+	}
+
+	tmp = g_malloc (nvalues * sizeof (GVariant*));
+	for (i = 0; i < ncal; i++)
+		tmp[i] = g_variant_new_int32 (cal[i]);
+
+	array = g_variant_new_array (G_VARIANT_TYPE_INT32, tmp, nvalues);
+	g_settings_set_value (settings, "area", array);
+
+	g_free (tmp);
+	g_variant_unref (array);
+}
+
+static gboolean
+run_calibration (gint  *cal,
+                 gsize  ncal)
+{
+	gboolean success = FALSE;
+	XYinfo axys;
+	bool swap_xy;
+	struct Calib calibrator;
+
+	if (ncal != 4)
+	{
+		g_warning("Unable to run calibration. Got %d items; expected %d.\n", ncal, 4);
+		goto quit_calibration;
+	}
+
+	calibrator.threshold_misclick = 15;
+	calibrator.threshold_doubleclick = 7;
+	calibrator.geometry = NULL;
+	calibrator.old_axys.x_min = cal[0];
+	calibrator.old_axys.y_min = cal[1];
+	calibrator.old_axys.x_max = cal[2];
+	calibrator.old_axys.y_max = cal[3];
+
+	/* !!NOTE!! This call blocks on the calibration
+         * !!NOTE!! process. It will be several seconds
+         * !!NOTE!! before this returns.
+         */
+	if(run_gui(&calibrator, &axys, &swap_xy))
+		success = TRUE;
+
+quit_calibration:
+	if (success)
+	{
+		cal[0] = axys.x_min;
+		cal[1] = axys.y_min;
+		cal[2] = axys.x_max;
+		cal[3] = axys.y_max;
+	}
+
+	return success;
+}
+
+static void
+calibrate_button_clicked_cb (GtkButton *button, gpointer user_data)
+{
+    GSettings *tablet = CC_WACOM_PAGE(user_data)->priv->wacom_settings;
+    gint i, calibration[4];
+    gint *current;
+    gsize s;
+
+    get_calibration (&current, &s, tablet);
+    if (s != 4)
+    {
+        g_warning("Device calibration property has wrong length. Got %d items; expected %d.\n", s, 4);
+        return;
+    }
+
+    for (i = 0; i < 4; i++)
+        calibration[i] = current[i];
+
+    if (calibration[0] == -1 && calibration[1] == -1 && calibration[2] == -1 && calibration[3] == -1)
+        gsd_wacom_device_get_area(CC_WACOM_PAGE(user_data)->priv->stylus, &calibration);
+
+    if (run_calibration(calibration, 4))
+        set_calibration(calibration, 4, tablet);
+}
+
+
 static void
 set_feel_from_gsettings (GtkAdjustment *adjustment, GSettings *settings)
 {
@@ -391,6 +500,9 @@ cc_wacom_page_init (CcWacomPage *self)
 			  G_CALLBACK (tip_feel_value_changed_cb), self);
 	g_signal_connect (WID ("scale-eraser-feel"), "value-changed",
 			  G_CALLBACK (eraser_feel_value_changed_cb), self);
+	g_signal_connect (WID ("button-calibrate"), "clicked",
+			  G_CALLBACK (calibrate_button_clicked_cb), self);
+
 
 	combo = GTK_COMBO_BOX (WID ("combo-topbutton"));
 	combobox_text_cellrenderer (combo, BUTTONNAME_COLUMN);

panels/wacom/gsd-wacom-device.c

@@ -734,6 +734,42 @@ gsd_wacom_device_get_device_type (GsdWacomDevice *device)
 	return device->priv->type;
 }
 
+gboolean
+gsd_wacom_device_get_area (GsdWacomDevice *dev, gint *device_area)
+{
+        int i, id;
+        XDevice *device;
+        Atom area, realtype;
+        int rc, realformat;
+        unsigned long nitems, bytes_after;
+        unsigned char *data = NULL;
+
+        g_object_get (dev->priv->gdk_device, "device-id", &id, NULL);
+
+        area = XInternAtom (GDK_DISPLAY_XDISPLAY (gdk_display_get_default ()), "Wacom Tablet Area", False);
+
+        gdk_error_trap_push ();
+        device = XOpenDevice (GDK_DISPLAY_XDISPLAY (gdk_display_get_default ()), id);
+        if (gdk_error_trap_pop () || (device == NULL))
+                return FALSE;
+
+        gdk_error_trap_push ();
+        rc = XGetDeviceProperty (GDK_DISPLAY_XDISPLAY (gdk_display_get_default ()),
+                                 device, area, 0, 4, False,
+                                 XA_INTEGER, &realtype, &realformat, &nitems,
+                                 &bytes_after, &data);
+        if (gdk_error_trap_pop () || rc != Success || realtype == None || bytes_after != 0 || nitems != 4) {
+                XCloseDevice (GDK_DISPLAY_XDISPLAY (gdk_display_get_default ()), device);
+                return FALSE;
+        }
+
+        for (i = 0; i < nitems; i++)
+                device_area[i] = ((long*)data)[i];
+
+        XFree (data);
+        return TRUE;
+}
+
 const char *
 gsd_wacom_device_type_to_string (GsdWacomDeviceType type)
 {

panels/wacom/gsd-wacom-device.h

@@ -96,6 +96,8 @@ void             gsd_wacom_device_set_current_stylus (GsdWacomDevice *device,
 						      int             stylus_id);
 
 GsdWacomDeviceType gsd_wacom_device_get_device_type (GsdWacomDevice *device);
+gboolean         gsd_wacom_device_get_area         (GsdWacomDevice *dev,
+                                                    int *device_area);
 const char     * gsd_wacom_device_type_to_string   (GsdWacomDeviceType type);
 
 /* Helper and debug functions */