Add editor panel host lifecycle contract

new_editor/include/XCEditor/Core/UIEditorPanelHostLifecycle.h

@@ -0,0 +1,68 @@
+#pragma once
+
+#include <XCEditor/Core/UIEditorPanelRegistry.h>
+#include <XCEditor/Core/UIEditorWorkspaceSession.h>
+
+#include <cstdint>
+#include <string>
+#include <string_view>
+#include <vector>
+
+namespace XCEngine::UI::Editor {
+
+enum class UIEditorPanelHostLifecycleEventKind : std::uint8_t {
+    Attached = 0,
+    Detached,
+    Shown,
+    Hidden,
+    Activated,
+    Deactivated,
+    FocusGained,
+    FocusLost
+};
+
+std::string_view GetUIEditorPanelHostLifecycleEventKindName(
+    UIEditorPanelHostLifecycleEventKind kind);
+
+struct UIEditorPanelHostState {
+    std::string panelId = {};
+    bool attached = false;
+    bool visible = false;
+    bool active = false;
+    bool focused = false;
+};
+
+struct UIEditorPanelHostLifecycleEvent {
+    UIEditorPanelHostLifecycleEventKind kind = UIEditorPanelHostLifecycleEventKind::Attached;
+    std::string panelId = {};
+};
+
+struct UIEditorPanelHostLifecycleState {
+    std::vector<UIEditorPanelHostState> panelStates = {};
+};
+
+struct UIEditorPanelHostLifecycleRequest {
+    std::string focusedPanelId = {};
+};
+
+struct UIEditorPanelHostLifecycleFrame {
+    std::vector<UIEditorPanelHostState> panelStates = {};
+    std::vector<UIEditorPanelHostLifecycleEvent> events = {};
+};
+
+const UIEditorPanelHostState* FindUIEditorPanelHostState(
+    const UIEditorPanelHostLifecycleState& state,
+    std::string_view panelId);
+
+const UIEditorPanelHostState* FindUIEditorPanelHostState(
+    const UIEditorPanelHostLifecycleFrame& frame,
+    std::string_view panelId);
+
+UIEditorPanelHostLifecycleFrame UpdateUIEditorPanelHostLifecycle(
+    UIEditorPanelHostLifecycleState& state,
+    const UIEditorPanelRegistry& panelRegistry,
+    const UIEditorWorkspaceModel& workspace,
+    const UIEditorWorkspaceSession& session,
+    const UIEditorPanelHostLifecycleRequest& request = {});
+
+} // namespace XCEngine::UI::Editor