From 7af96b27241f86e5c74b2850bd85b9a3c39f28ef Mon Sep 17 00:00:00 2001
From: Thomas Gubler <thomasgubler@gmail.com>
Date: Fri, 27 Dec 2013 12:51:30 +0100
Subject: [PATCH] sorted parameters: make search more efficient

---
 src/ui/QGCParamWidget.cc | 48 ++++++++++++++++++++++++++++++----------
 src/ui/QGCParamWidget.h  |  4 +++-
 2 files changed, 39 insertions(+), 13 deletions(-)

diff --git a/src/ui/QGCParamWidget.cc b/src/ui/QGCParamWidget.cc
index d9c8c2a7b..f241196b6 100644
--- a/src/ui/QGCParamWidget.cc
+++ b/src/ui/QGCParamWidget.cc
@@ -311,6 +311,39 @@ QTreeWidgetItem* QGCParamWidget::getParentWidgetItemForParam(int compId, const Q
     return parentItem;
 }
 
+void QGCParamWidget::insertParamAlphabetical(int indexLowerBound, int indexUpperBound, QTreeWidgetItem* parentItem, QTreeWidgetItem* paramItem)
+{
+    if (indexLowerBound >= indexUpperBound)
+    {
+        if (paramItem->text(0).compare(parentItem->child(indexLowerBound)->text(0)) < 0) {
+            parentItem->insertChild(indexLowerBound, paramItem);
+        }
+        else
+        {
+            if (indexLowerBound < parentItem->childCount() - 1) {
+                parentItem->insertChild(indexLowerBound + 1, paramItem);
+            }
+            else
+            {
+                parentItem->addChild(paramItem);
+            }
+        }
+    }
+    else
+    {
+        int midpoint = indexLowerBound + floor(indexUpperBound - indexLowerBound)/2;
+
+        if (paramItem->text(0).compare(parentItem->child(midpoint)->text(0)) < 0)
+        {
+            insertParamAlphabetical(indexLowerBound, midpoint - 1, parentItem, paramItem);
+        } else
+        {
+            insertParamAlphabetical(midpoint + 1, indexUpperBound, parentItem, paramItem);
+        }
+
+    }
+}
+
 QTreeWidgetItem* QGCParamWidget::updateParameterDisplay(int compId, QString parameterName, QVariant value)
 {
     //qDebug() << "QGCParamWidget::updateParameterDisplay" << parameterName;
@@ -344,19 +377,10 @@ QTreeWidgetItem* QGCParamWidget::updateParameterDisplay(int compId, QString para
             paramItem->setFlags(paramItem->flags() | Qt::ItemIsEditable);
 
             //Insert alphabetically
-            bool inserted = false;
-            for(int i = 0; i < parentItem->childCount(); i++) {
-                if (parameterName.compare(parentItem->child(i)->text(0)) < 0 )
-                {
-                    parentItem->insertChild(i, paramItem);
-                    inserted = true;
-                    break;
-                }
-            }
-
-            if (!inserted)
+            if (parentItem->childCount() > 0) {
+                insertParamAlphabetical(0, parentItem->childCount() - 1, parentItem, paramItem);
+            } else
             {
-                //Insert at the end
                 parentItem->addChild(paramItem);
             }
 
diff --git a/src/ui/QGCParamWidget.h b/src/ui/QGCParamWidget.h
index 83787de1d..98b5d044a 100644
--- a/src/ui/QGCParamWidget.h
+++ b/src/ui/QGCParamWidget.h
@@ -83,10 +83,12 @@ public slots:
     virtual void clearOnboardParamDisplay();
     virtual void clearPendingParamDisplay();
 
+    /** @brief Adds parameter at the correct location by a alphapetical comparison of the parameter names */
+    void insertParamAlphabetical(int indexLowerBound, int indexUpperBound, QTreeWidgetItem* parentItem, QTreeWidgetItem* paramItem);
+
     /** @brief Ensure that view of parameter matches data in the model */
     QTreeWidgetItem* updateParameterDisplay(int component, QString parameterName, QVariant value);
 
-
     /** @brief Update when user changes parameters */
     void parameterItemChanged(QTreeWidgetItem* prev, int column);
 
-- 
2.22.0