From 8cc3154c72442160f57e6e5eb400b05bdb8cd3a9 Mon Sep 17 00:00:00 2001
From: Martin Kleusberg <mkleusberg@gmail.com>
Date: Sun, 14 May 2017 21:37:11 +0200
Subject: [PATCH] Add button for adding expression columns in Edit Index dialog

Add a button for adding new expression columns to the Edit Index dialog.

Allow the user to edit the 'name' of existing expression columns in the
Edit Index dialog.
---
 src/EditIndexDialog.cpp | 49 ++++++++++++++++++++++++++++++++++++-----
 src/EditIndexDialog.h   |  1 +
 src/EditIndexDialog.ui  | 34 +++++++++++++++++++++++++---
 3 files changed, 76 insertions(+), 8 deletions(-)

diff --git a/src/EditIndexDialog.cpp b/src/EditIndexDialog.cpp
index 608654e5..1397c6b9 100644
--- a/src/EditIndexDialog.cpp
+++ b/src/EditIndexDialog.cpp
@@ -54,6 +54,14 @@ EditIndexDialog::EditIndexDialog(DBBrowserDB& db, const QString& indexName, bool
         tableChanged(ui->comboTableName->currentText(), false);
     }
 
+    // Add event handler for index column name changes. These are only allowed for expression columns, though.
+    connect(ui->tableIndexColumns, static_cast<void(QTableWidget::*)(QTableWidgetItem*)>(&QTableWidget::itemChanged),
+            [=](QTableWidgetItem* item)
+    {
+        index.columns().at(item->row())->setName(item->text());
+        updateSqlText();
+    });
+
     // Create a savepoint to revert back to
     pdb.setSavepoint(m_sRestorePointName);
 }
@@ -115,13 +123,17 @@ void EditIndexDialog::updateColumnLists()
 
     // Fill the index column list. This is done separately from the table column to include expression columns (these are not found in the original
     // table) and to preserve the order of the index columns
-    sqlb::FieldInfoList indexFields = index.fieldInformation();
+    auto indexFields = index.columns();
+    ui->tableIndexColumns->blockSignals(true);
     ui->tableIndexColumns->setRowCount(indexFields.size());
     for(int i=0;i<indexFields.size();++i)
     {
         // Put the name of the field in the first column
-        QTableWidgetItem* name = new QTableWidgetItem(indexFields.at(i).name);
-        name->setFlags(Qt::ItemIsSelectable | Qt::ItemIsEnabled);
+        QTableWidgetItem* name = new QTableWidgetItem(indexFields.at(i)->name());
+        Qt::ItemFlags flags = Qt::ItemIsSelectable | Qt::ItemIsEnabled;
+        if(indexFields.at(i)->expression())
+            flags |= Qt::ItemIsEditable;
+        name->setFlags(flags);
         ui->tableIndexColumns->setItem(i, 0, name);
 
         // And put a combobox to select the order in which to index the field in the last column
@@ -129,12 +141,12 @@ void EditIndexDialog::updateColumnLists()
         order->addItem("");
         order->addItem("ASC");
         order->addItem("DESC");
-        order->setCurrentText(indexFields.at(i).type.toUpper());
+        order->setCurrentText(indexFields.at(i)->order().toUpper());
         ui->tableIndexColumns->setCellWidget(i, 1, order);
         connect(order, static_cast<void(QComboBox::*)(const QString&)>(&QComboBox::currentTextChanged),
                 [=](QString new_order)
         {
-            int colnum = index.findColumn(indexFields.at(i).name);
+            int colnum = index.findColumn(indexFields.at(i)->name());
             if(colnum != -1)
             {
                 index.column(colnum)->setOrder(new_order);
@@ -142,6 +154,7 @@ void EditIndexDialog::updateColumnLists()
             }
         });
     }
+    ui->tableIndexColumns->blockSignals(false);
 
     checkInput();
 }
@@ -275,3 +288,29 @@ void EditIndexDialog::moveCurrentColumn(bool down)
     // Select old row at new position
     ui->tableIndexColumns->selectRow(newRow);
 }
+
+void EditIndexDialog::addExpressionColumn()
+{
+    // Check if there already is an empty expression column
+    int row = index.findColumn("");
+    if(row == -1)
+    {
+        // There is no empty expression column yet, so add one.
+
+        // Add new expression column to the index
+        index.addColumn(sqlb::IndexedColumnPtr(new sqlb::IndexedColumn(
+                                                   "",                          // Column name
+                                                   true,                        // Is expression
+                                                   "")));                       // Order
+
+        // Update UI
+        updateColumnLists();
+
+        // Get row number of new column
+        row = ui->tableIndexColumns->rowCount() - 1;
+    }
+
+    // Now we should have the row number of the empty expression column, no matter if it was newly added or it already existed.
+    // Select the row for editing
+    ui->tableIndexColumns->editItem(ui->tableIndexColumns->item(row, 0));
+}
diff --git a/src/EditIndexDialog.h b/src/EditIndexDialog.h
index 2b2ee4ca..ba967b90 100644
--- a/src/EditIndexDialog.h
+++ b/src/EditIndexDialog.h
@@ -30,6 +30,7 @@ private slots:
     void removeFromIndex(const QModelIndex& idx = QModelIndex());
     void moveColumnUp();
     void moveColumnDown();
+    void addExpressionColumn();
 
 private:
     DBBrowserDB& pdb;
diff --git a/src/EditIndexDialog.ui b/src/EditIndexDialog.ui
index bb3a2cab..4477fbcf 100644
--- a/src/EditIndexDialog.ui
+++ b/src/EditIndexDialog.ui
@@ -166,6 +166,17 @@
              </property>
             </widget>
            </item>
+           <item>
+            <widget class="QToolButton" name="buttonAddExpressionColumn">
+             <property name="toolTip">
+              <string>Add a new expression column to the index. Expression columns contain SQL expression rather than column names.</string>
+             </property>
+             <property name="icon">
+              <iconset resource="icons/icons.qrc">
+               <normaloff>:/icons/cog_go.png</normaloff>:/icons/cog_go.png</iconset>
+             </property>
+            </widget>
+           </item>
            <item>
             <spacer name="verticalSpacer_2">
              <property name="orientation">
@@ -196,7 +207,7 @@
             </size>
            </property>
            <property name="editTriggers">
-            <set>QAbstractItemView::NoEditTriggers</set>
+            <set>QAbstractItemView::AnyKeyPressed|QAbstractItemView::EditKeyPressed|QAbstractItemView::SelectedClicked</set>
            </property>
            <property name="showDropIndicator" stdset="0">
             <bool>false</bool>
@@ -427,7 +438,7 @@
    <hints>
     <hint type="sourcelabel">
      <x>406</x>
-     <y>266</y>
+     <y>247</y>
     </hint>
     <hint type="destinationlabel">
      <x>385</x>
@@ -443,7 +454,7 @@
    <hints>
     <hint type="sourcelabel">
      <x>406</x>
-     <y>304</y>
+     <y>285</y>
     </hint>
     <hint type="destinationlabel">
      <x>350</x>
@@ -531,6 +542,22 @@
     </hint>
    </hints>
   </connection>
+  <connection>
+   <sender>buttonAddExpressionColumn</sender>
+   <signal>clicked()</signal>
+   <receiver>EditIndexDialog</receiver>
+   <slot>addExpressionColumn()</slot>
+   <hints>
+    <hint type="sourcelabel">
+     <x>398</x>
+     <y>311</y>
+    </hint>
+    <hint type="destinationlabel">
+     <x>379</x>
+     <y>500</y>
+    </hint>
+   </hints>
+  </connection>
  </connections>
  <slots>
   <slot>tableChanged(QString)</slot>
@@ -541,5 +568,6 @@
   <slot>removeFromIndex(QModelIndex)</slot>
   <slot>moveColumnUp()</slot>
   <slot>moveColumnDown()</slot>
+  <slot>addExpressionColumn()</slot>
  </slots>
 </ui>