[code] Delete specific lines in the console history with backspace.

Change-Id: I9ed4709937f35c67aea0b958fabbad145b8c0c80

apps/code/console_controller.cpp

@@ -126,6 +126,14 @@ bool ConsoleController::handleEvent(Ion::Events::Event event) {
     m_selectableTableView.reloadData();
     m_selectableTableView.selectCellAtLocation(0, m_consoleStore.numberOfLines());
     return true;
+  } else if (event == Ion::Events::Backspace) {
+    int selectedRow = m_selectableTableView.selectedRow();
+    assert(selectedRow >= 0 && selectedRow < m_consoleStore.numberOfLines());
+    m_selectableTableView.deselectTable();
+    int firstDeletedLineIndex = m_consoleStore.deleteCommandAndResultsAtIndex(selectedRow);
+    m_selectableTableView.reloadData();
+    m_selectableTableView.selectCellAtLocation(0, firstDeletedLineIndex);
+    return true;
   }
   return false;
 }

apps/code/console_store.cpp

@@ -80,6 +80,26 @@ void ConsoleStore::deleteLastLineIfEmpty() {
   }
 }
 
+int ConsoleStore::deleteCommandAndResultsAtIndex(int index) {
+  int numberOfLinesAtStart = numberOfLines();
+  assert(index >= 0 && index < numberOfLinesAtStart);
+  int indexOfLineToDelete = index;
+  while (indexOfLineToDelete < numberOfLinesAtStart - 1) {
+   if (lineAtIndex(indexOfLineToDelete + 1).isCommand()) {
+     break;
+   }
+   indexOfLineToDelete++;
+  }
+  ConsoleLine lineToDelete = lineAtIndex(indexOfLineToDelete);
+  while (indexOfLineToDelete > 0 && !lineAtIndex(indexOfLineToDelete).isCommand()) {
+    deleteLineAtIndex(indexOfLineToDelete);
+    indexOfLineToDelete--;
+    lineToDelete = lineAtIndex(indexOfLineToDelete);
+  }
+  deleteLineAtIndex(indexOfLineToDelete);
+  return indexOfLineToDelete;
+}
+
 void ConsoleStore::push(const char marker, const char * text, size_t length) {
   // TODO: Verify that the text field does not accept texts that are bigger than
   // k_historySize, or put an alert message if the command is too big.
@@ -114,6 +134,26 @@ int ConsoleStore::indexOfNullMarker() const {
   return 0;
 }
 
+void ConsoleStore::deleteLineAtIndex(int index) {
+  assert(index >=0 && index < numberOfLines());
+  int currentLineIndex = 0;
+  for (int i = 0; i < k_historySize - 1; i++) {
+    if (m_history[i] == 0) {
+      currentLineIndex++;
+      continue;
+    }
+    if (currentLineIndex == index) {
+      int nextLineStart = i;
+      while (m_history[nextLineStart] != 0 && nextLineStart < k_historySize - 2) {
+        nextLineStart++;
+      }
+      nextLineStart++;
+      memcpy(&m_history[i], &m_history[nextLineStart], (k_historySize - 1) - nextLineStart + 1);
+      return;
+    }
+  }
+}
+
 void ConsoleStore::deleteFirstLine() {
   if (m_history[0] == 0) {
     return;

apps/code/console_store.h

@@ -16,6 +16,7 @@ public:
   void pushCommand(const char * text, size_t length);
   void pushResult(const char * text, size_t length);
   void deleteLastLineIfEmpty();
+  int deleteCommandAndResultsAtIndex(int index);
 private:
   static constexpr char CurrentSessionCommandMarker = 0x01;
   static constexpr char CurrentSessionResultMarker = 0x02;
@@ -31,6 +32,7 @@ private:
   void push(const char marker, const char * text, size_t length);
   ConsoleLine::Type lineTypeForMarker(char marker) const;
   int indexOfNullMarker() const;
+  void deleteLineAtIndex(int index);
   void deleteFirstLine();
   /* When there is no room left to store a new ConsoleLine, we have to delete
    * old ConsoleLines. deleteFirstLine() deletes the first ConsoleLine of