1 files changed, 105 insertions, 0 deletions
diff --git a/js/navigation.js b/js/navigation.js
new file mode 100644
index 0000000..dfad74b
--- /dev/null
+++ b/js/navigation.js
@@ -0,0 +1,105 @@
+/*
+ * Navigation allows movement using the arrow keys through the search results.
+ *
+ * When using this library you will need to set scrollIntoView to the
+ * appropriate function for your layout.  Use scrollInWindow if the container
+ * is not scrollable and scrollInElement if the container is a separate
+ * scrolling region.
+ */
+Navigation = new function() {
+  this.initNavigation = function() {
+    var _this = this;
+
+    document.addEventListener('keydown', function(e) {
+      _this.onkeydown(e);
+    });
+
+    this.navigationActive = true;
+  }
+
+  this.setNavigationActive = function(state) {
+    this.navigationActive = state;
+  }
+
+  this.onkeydown = function(e) {
+    if (!this.navigationActive) return;
+    switch(e.keyCode) {
+      case 37: //Event.KEY_LEFT:
+        if (this.moveLeft()) e.preventDefault();
+        break;
+      case 38: //Event.KEY_UP:
+        if (e.keyCode == 38 || e.ctrlKey) {
+          if (this.moveUp()) e.preventDefault();
+        }
+        break;
+      case 39: //Event.KEY_RIGHT:
+        if (this.moveRight()) e.preventDefault();
+        break;
+      case 40: //Event.KEY_DOWN:
+        if (e.keyCode == 40 || e.ctrlKey) {
+          if (this.moveDown()) e.preventDefault();
+        }
+        break;
+      case 13: //Event.KEY_RETURN:
+        if (this.current) e.preventDefault();
+        this.select(this.current);
+        break;
+    }
+    if (e.ctrlKey && e.shiftKey) this.select(this.current);
+  }
+
+  this.moveRight = function() {
+  }
+
+  this.moveLeft = function() {
+  }
+
+  this.move = function(isDown) {
+  }
+
+  this.moveUp = function() {
+    return this.move(false);
+  }
+
+  this.moveDown = function() {
+    return this.move(true);
+  }
+
+  /*
+   * Scrolls to the given element in the scrollable element view.
+   */
+  this.scrollInElement = function(element, view) {
+    var offset, viewHeight, viewScroll, height;
+    offset = element.offsetTop;
+    height = element.offsetHeight;
+    viewHeight = view.offsetHeight;
+    viewScroll = view.scrollTop;
+
+    if (offset - viewScroll + height > viewHeight) {
+      view.scrollTop = offset - viewHeight + height;
+    }
+    if (offset < viewScroll) {
+      view.scrollTop = offset;
+    }
+  }
+
+  /*
+   * Scrolls to the given element in the window.  The second argument is
+   * ignored
+   */
+  this.scrollInWindow = function(element, ignored) {
+    var offset, viewHeight, viewScroll, height;
+    offset = element.offsetTop;
+    height = element.offsetHeight;
+    viewHeight = window.innerHeight;
+    viewScroll = window.scrollY;
+
+    if (offset - viewScroll + height > viewHeight) {
+      window.scrollTo(window.scrollX, offset - viewHeight + height);
+    }
+    if (offset < viewScroll) {
+      window.scrollTo(window.scrollX, offset);
+    }
+  }
+}
+