#pragma once

#include "State/EditorSelectionStamp.h"
#include "State/EditorSession.h"

#include <filesystem>
#include <string>
#include <string_view>
#include <utility>

namespace XCEngine::UI::Editor::App {

class EditorSelectionService {
public:
    const EditorSelectionState& GetSelection() const {
        return m_selection;
    }

    bool HasSelection() const {
        return m_selection.kind != EditorSelectionKind::None &&
            !m_selection.itemId.empty();
    }

    bool HasSelectionKind(EditorSelectionKind kind) const {
        return m_selection.kind == kind && HasSelection();
    }

    std::uint64_t GetStamp() const {
        return m_selection.stamp;
    }

    bool SetProjectSelection(
        std::string_view itemId,
        std::string_view displayName,
        const std::filesystem::path& absolutePath,
        bool directory) {
        EditorSelectionState selection = {};
        selection.kind = EditorSelectionKind::ProjectItem;
        selection.itemId = std::string(itemId);
        selection.displayName = std::string(displayName);
        selection.absolutePath = absolutePath;
        selection.directory = directory;
        const bool changed =
            m_selection.kind != selection.kind ||
            m_selection.itemId != selection.itemId ||
            m_selection.absolutePath != selection.absolutePath ||
            m_selection.directory != selection.directory;
        ApplySelection(std::move(selection), changed);
        return changed;
    }

    bool SetHierarchySelection(
        std::string_view itemId,
        std::string_view displayName = {}) {
        EditorSelectionState selection = {};
        selection.kind = EditorSelectionKind::HierarchyNode;
        selection.itemId = std::string(itemId);
        selection.displayName = std::string(displayName);
        const bool changed =
            m_selection.kind != selection.kind ||
            m_selection.itemId != selection.itemId;
        ApplySelection(std::move(selection), changed);
        return changed;
    }

    void SetSelection(EditorSelectionState selection) {
        bool changed = true;
        switch (selection.kind) {
        case EditorSelectionKind::ProjectItem:
            changed =
                m_selection.kind != selection.kind ||
                m_selection.itemId != selection.itemId ||
                m_selection.absolutePath != selection.absolutePath ||
                m_selection.directory != selection.directory;
            break;

        case EditorSelectionKind::HierarchyNode:
            changed =
                m_selection.kind != selection.kind ||
                m_selection.itemId != selection.itemId;
            break;

        case EditorSelectionKind::None:
        default:
            ClearSelection();
            return;
        }

        ApplySelection(std::move(selection), changed);
    }

    void ClearSelection() {
        m_selection = {};
        m_selection.stamp = GenerateEditorSelectionStamp();
    }

private:
    void ApplySelection(
        EditorSelectionState selection,
        bool changed) {
        const std::uint64_t previousStamp = m_selection.stamp;
        selection.stamp = changed
            ? GenerateEditorSelectionStamp()
            : (previousStamp != 0u ? previousStamp : GenerateEditorSelectionStamp());
        m_selection = std::move(selection);
    }

    EditorSelectionState m_selection = {};
};

} // namespace XCEngine::UI::Editor::App