1 files changed, 96 insertions, 0 deletions
diff --git a/src/squelch/cursor.cc b/src/squelch/cursor.cc
new file mode 100644
index 00000000..3a3bec46
--- /dev/null
+++ b/src/squelch/cursor.cc
@@ -0,0 +1,96 @@
+#include "tome/squelch/cursor_fwd.hpp"
+#include "tome/squelch/cursor.hpp"
+
+#include <algorithm>
+#include <cassert>
+
+#include "tome/squelch/condition.hpp"
+
+namespace squelch {
+
+bool Cursor::is_selected(Condition const *condition) const
+{
+	return std::end(m_conditions) !=
+		std::find(std::begin(m_conditions),
+			  std::end(m_conditions),
+			  condition);
+}
+
+Condition *Cursor::pop()
+{
+	assert(!m_conditions.empty());
+	Condition *c = m_conditions.back();
+	m_conditions.pop_back();
+	return c;
+}
+
+Condition *Cursor::current()
+{
+	assert(!m_conditions.empty());
+	return m_conditions.back();
+}
+
+void Cursor::move_right()
+{
+	if (m_conditions.empty()) {
+		return;
+	}
+	// Go right if the currently selected condition has children.
+	std::shared_ptr<Condition> c = current()->first_child();
+	if (c)
+	{
+		push(c.get());
+	}
+}
+
+void Cursor::move_left()
+{
+	if (size() > 1)
+	{
+		pop();
+	}
+}
+
+void Cursor::move_up()
+{
+	if (size() > 1)
+	{
+		Condition *prev_top = pop();
+
+		// Find previous child
+		std::shared_ptr<Condition> prev_condition =
+			current()->previous_child(prev_top);
+
+		// Do we have a previous child?
+		if (prev_condition)
+		{
+			push(prev_condition.get());
+		}
+		else
+		{
+			push(prev_top);
+		}
+	}
+}
+
+void Cursor::move_down()
+{
+	if (size() > 1)
+	{
+		Condition *prev_top = pop();
+
+		std::shared_ptr<Condition> next_condition =
+			current()->next_child(prev_top);
+
+		if (next_condition)
+		{
+			push(next_condition.get());
+		}
+		else
+		{
+			push(prev_top);
+		}
+	}
+}
+
+} // namespace