1 files changed, 56 insertions, 0 deletions
diff --git a/src/search/updatablestateinterface.h b/src/search/updatablestateinterface.h
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+++ b/src/search/updatablestateinterface.h
@@ -0,0 +1,56 @@
+/*
+    SPDX-FileCopyrightText: 2024 Felix Ernst <[email protected]>
+
+    SPDX-License-Identifier: LGPL-2.1-only OR LGPL-3.0-only OR LicenseRef-KDE-Accepted-LGPL
+*/
+
+#ifndef UPDATABLESTATEINTERFACE_H
+#define UPDATABLESTATEINTERFACE_H
+
+#include <QtAssert>
+
+#include <memory>
+
+namespace Search
+{
+class DolphinQuery;
+
+class UpdatableStateInterface
+{
+public:
+    inline explicit UpdatableStateInterface(std::shared_ptr<const DolphinQuery> dolphinQuery)
+        : m_searchConfiguration{std::move(dolphinQuery)} {};
+
+    virtual ~UpdatableStateInterface(){};
+
+    /**
+     * Updates this object and its child widgets so their states are correctly described by the @p dolphinQuery.
+     * This method is always initially called on the Search::Bar which in turn calls this method on its child widgets. That is because the Search::Bar is the
+     * ancestor widget of all classes implementing UpdatableStateInterface, and from Search::Bar::updateStateToMatch() the changed state represented by the
+     * @p dolphinQuery is propagated to all other UpdatableStateInterfaces through UpdatableStateInterface::updateState() calls.
+     */
+    inline void updateStateToMatch(std::shared_ptr<const DolphinQuery> dolphinQuery)
+    {
+        Q_ASSERT_X(m_searchConfiguration, "UpdatableStateInterface::updateStateToMatch()", "An UpdatableStateInterface should always have a consistent state.");
+        updateState(dolphinQuery);
+        m_searchConfiguration = std::move(dolphinQuery);
+        Q_ASSERT_X(m_searchConfiguration, "UpdatableStateInterface::updateStateToMatch()", "An UpdatableStateInterface should always have a consistent state.");
+    };
+
+private:
+    /**
+     * Implementations of this method initialize the state of this object and its child widgets to represent the state of the @p dolphinQuery.
+     * This method is only ever called from UpdatableStateInterface::updateStateToMatch().
+     */
+    virtual void updateState(const std::shared_ptr<const DolphinQuery> &dolphinQuery) = 0;
+
+protected:
+    /**
+     * The DolphinQuery that was used to initialize this object's state.
+     */
+    std::shared_ptr<const DolphinQuery> m_searchConfiguration;
+};
+
+}
+
+#endif // UPDATABLESTATEINTERFACE_H