#include <XCEditor/Workspace/UIEditorDetachedWindowPolicy.h>

namespace XCEngine::UI::Editor {

namespace {

bool IsRootPanelVisible(
    const UIEditorWorkspaceController& controller,
    std::string_view panelId) {
    const UIEditorPanelSessionState* panelState =
        FindUIEditorPanelSessionState(controller.GetSession(), panelId);
    return panelState != nullptr && panelState->open && panelState->visible;
}

} // namespace

const UIEditorPanelDescriptor* ResolveUIEditorSingleVisibleRootPanelDescriptor(
    const UIEditorWorkspaceController& controller) {
    const UIEditorWorkspaceNode& root = controller.GetWorkspace().root;
    if (root.kind != UIEditorWorkspaceNodeKind::TabStack) {
        return nullptr;
    }

    const UIEditorPanelRegistry& panelRegistry = controller.GetPanelRegistry();
    const UIEditorPanelDescriptor* visibleDescriptor = nullptr;
    std::size_t visibleCount = 0u;
    for (const UIEditorWorkspaceNode& child : root.children) {
        if (child.kind != UIEditorWorkspaceNodeKind::Panel ||
            !IsRootPanelVisible(controller, child.panel.panelId)) {
            continue;
        }

        const UIEditorPanelDescriptor* descriptor =
            FindUIEditorPanelDescriptor(panelRegistry, child.panel.panelId);
        if (descriptor == nullptr) {
            return nullptr;
        }

        ++visibleCount;
        visibleDescriptor = descriptor;
        if (visibleCount > 1u) {
            return nullptr;
        }
    }

    return visibleCount == 1u ? visibleDescriptor : nullptr;
}

bool HasUIEditorSingleVisibleRootTab(
    const UIEditorWorkspaceController& controller) {
    return ResolveUIEditorSingleVisibleRootPanelDescriptor(controller) != nullptr;
}

std::string ResolveUIEditorDetachedWorkspaceTitle(
    const UIEditorWorkspaceController& controller,
    std::string_view fallbackTitle) {
    const std::string& activePanelId = controller.GetWorkspace().activePanelId;
    if (const UIEditorPanelDescriptor* descriptor =
            FindUIEditorPanelDescriptor(controller.GetPanelRegistry(), activePanelId);
        descriptor != nullptr &&
        !descriptor->defaultTitle.empty()) {
        return descriptor->defaultTitle;
    }

    return std::string(fallbackTitle);
}

::XCEngine::UI::UISize ResolveUIEditorDetachedWorkspaceMinimumOuterSize(
    const UIEditorWorkspaceController& controller,
    const ::XCEngine::UI::UISize& fallbackSize) {
    if (const UIEditorPanelDescriptor* descriptor =
            ResolveUIEditorSingleVisibleRootPanelDescriptor(controller);
        descriptor != nullptr &&
        descriptor->minimumDetachedWindowSize.width > 0.0f &&
        descriptor->minimumDetachedWindowSize.height > 0.0f) {
        return descriptor->minimumDetachedWindowSize;
    }

    return fallbackSize;
}

} // namespace XCEngine::UI::Editor