1 files changed, 77 insertions, 0 deletions
diff --git a/js/ui/edgeDragAction.js b/js/ui/edgeDragAction.js
new file mode 100644
index 0000000..8502170
--- /dev/null
+++ b/js/ui/edgeDragAction.js
@@ -0,0 +1,77 @@
+// -*- mode: js; js-indent-level: 4; indent-tabs-mode: nil -*-
+/* exported EdgeDragAction */
+
+const { Clutter, GObject, Meta, St } = imports.gi;
+
+const Main = imports.ui.main;
+
+var EDGE_THRESHOLD = 20;
+var DRAG_DISTANCE = 80;
+
+var EdgeDragAction = GObject.registerClass({
+    Signals: { 'activated': {} },
+}, class EdgeDragAction extends Clutter.GestureAction {
+    _init(side, allowedModes) {
+        super._init();
+        this._side = side;
+        this._allowedModes = allowedModes;
+        this.set_n_touch_points(1);
+
+        global.display.connect('grab-op-begin', () => this.cancel());
+    }
+
+    _getMonitorRect(x, y) {
+        let rect = new Meta.Rectangle({ x: x - 1, y: y - 1, width: 1, height: 1 });
+        let monitorIndex = global.display.get_monitor_index_for_rect(rect);
+
+        return global.display.get_monitor_geometry(monitorIndex);
+    }
+
+    vfunc_gesture_prepare(_actor) {
+        if (this.get_n_current_points() == 0)
+            return false;
+
+        if (!(this._allowedModes & Main.actionMode))
+            return false;
+
+        let [x, y] = this.get_press_coords(0);
+        let monitorRect = this._getMonitorRect(x, y);
+
+        return (this._side == St.Side.LEFT && x < monitorRect.x + EDGE_THRESHOLD) ||
+                (this._side == St.Side.RIGHT && x > monitorRect.x + monitorRect.width - EDGE_THRESHOLD) ||
+                (this._side == St.Side.TOP && y < monitorRect.y + EDGE_THRESHOLD) ||
+                (this._side == St.Side.BOTTOM && y > monitorRect.y + monitorRect.height - EDGE_THRESHOLD);
+    }
+
+    vfunc_gesture_progress(_actor) {
+        let [startX, startY] = this.get_press_coords(0);
+        let [x, y] = this.get_motion_coords(0);
+        let offsetX = Math.abs(x - startX);
+        let offsetY = Math.abs(y - startY);
+
+        if (offsetX < EDGE_THRESHOLD && offsetY < EDGE_THRESHOLD)
+            return true;
+
+        if ((offsetX > offsetY &&
+             (this._side == St.Side.TOP || this._side == St.Side.BOTTOM)) ||
+            (offsetY > offsetX &&
+             (this._side == St.Side.LEFT || this._side == St.Side.RIGHT))) {
+            this.cancel();
+            return false;
+        }
+
+        return true;
+    }
+
+    vfunc_gesture_end(_actor) {
+        let [startX, startY] = this.get_press_coords(0);
+        let [x, y] = this.get_motion_coords(0);
+        let monitorRect = this._getMonitorRect(startX, startY);
+
+        if ((this._side == St.Side.TOP && y > monitorRect.y + DRAG_DISTANCE) ||
+            (this._side == St.Side.BOTTOM && y < monitorRect.y + monitorRect.height - DRAG_DISTANCE) ||
+            (this._side == St.Side.LEFT && x > monitorRect.x + DRAG_DISTANCE) ||
+            (this._side == St.Side.RIGHT && x < monitorRect.x + monitorRect.width - DRAG_DISTANCE))
+            this.emit('activated');
+    }
+});