#pragma once

#include <XCEngine/UI/DrawData.h>
#include <XCEngine/UI/Widgets/UIExpansionModel.h>
#include <XCEngine/UI/Widgets/UISelectionModel.h>

#include <cstddef>
#include <cstdint>
#include <string>
#include <string_view>
#include <vector>

namespace XCEngine::UI::Editor::Widgets {

inline constexpr std::size_t UIEditorTreeViewInvalidIndex = static_cast<std::size_t>(-1);

enum class UIEditorTreeViewHitTargetKind : std::uint8_t {
    None = 0,
    Row,
    Disclosure
};

struct UIEditorTreeViewItem {
    std::string itemId = {};
    std::string label = {};
    std::uint32_t depth = 0u;
    bool forceLeaf = false;
    float desiredHeight = 0.0f;
};

struct UIEditorTreeViewState {
    std::string hoveredItemId = {};
    bool focused = false;
};

struct UIEditorTreeViewMetrics {
    float rowHeight = 28.0f;
    float rowGap = 2.0f;
    float horizontalPadding = 8.0f;
    float indentWidth = 18.0f;
    float disclosureExtent = 12.0f;
    float disclosureLabelGap = 6.0f;
    float labelInsetY = 6.0f;
    float cornerRounding = 6.0f;
    float borderThickness = 1.0f;
    float focusedBorderThickness = 2.0f;
};

struct UIEditorTreeViewPalette {
    ::XCEngine::UI::UIColor surfaceColor =
        ::XCEngine::UI::UIColor(0.14f, 0.14f, 0.14f, 1.0f);
    ::XCEngine::UI::UIColor borderColor =
        ::XCEngine::UI::UIColor(0.29f, 0.29f, 0.29f, 1.0f);
    ::XCEngine::UI::UIColor focusedBorderColor =
        ::XCEngine::UI::UIColor(0.84f, 0.84f, 0.84f, 1.0f);
    ::XCEngine::UI::UIColor rowHoverColor =
        ::XCEngine::UI::UIColor(0.24f, 0.24f, 0.24f, 1.0f);
    ::XCEngine::UI::UIColor rowSelectedColor =
        ::XCEngine::UI::UIColor(0.32f, 0.32f, 0.32f, 1.0f);
    ::XCEngine::UI::UIColor rowSelectedFocusedColor =
        ::XCEngine::UI::UIColor(0.40f, 0.40f, 0.40f, 1.0f);
    ::XCEngine::UI::UIColor disclosureColor =
        ::XCEngine::UI::UIColor(0.74f, 0.74f, 0.74f, 1.0f);
    ::XCEngine::UI::UIColor textColor =
        ::XCEngine::UI::UIColor(0.94f, 0.94f, 0.94f, 1.0f);
};

struct UIEditorTreeViewLayout {
    ::XCEngine::UI::UIRect bounds = {};
    std::vector<std::size_t> visibleItemIndices = {};
    std::vector<::XCEngine::UI::UIRect> rowRects = {};
    std::vector<::XCEngine::UI::UIRect> disclosureRects = {};
    std::vector<::XCEngine::UI::UIRect> labelRects = {};
    std::vector<bool> itemHasChildren = {};
    std::vector<bool> itemExpanded = {};
};

struct UIEditorTreeViewHitTarget {
    UIEditorTreeViewHitTargetKind kind = UIEditorTreeViewHitTargetKind::None;
    std::size_t visibleIndex = UIEditorTreeViewInvalidIndex;
    std::size_t itemIndex = UIEditorTreeViewInvalidIndex;
};

bool IsUIEditorTreeViewPointInside(
    const ::XCEngine::UI::UIRect& rect,
    const ::XCEngine::UI::UIPoint& point);

bool DoesUIEditorTreeViewItemHaveChildren(
    const std::vector<UIEditorTreeViewItem>& items,
    std::size_t itemIndex);

std::size_t FindUIEditorTreeViewItemIndex(
    const std::vector<UIEditorTreeViewItem>& items,
    std::string_view itemId);

std::size_t FindUIEditorTreeViewParentItemIndex(
    const std::vector<UIEditorTreeViewItem>& items,
    std::size_t itemIndex);

std::vector<std::size_t> CollectUIEditorTreeViewVisibleItemIndices(
    const std::vector<UIEditorTreeViewItem>& items,
    const ::XCEngine::UI::Widgets::UIExpansionModel& expansionModel);

std::size_t FindUIEditorTreeViewFirstVisibleChildItemIndex(
    const std::vector<UIEditorTreeViewItem>& items,
    const ::XCEngine::UI::Widgets::UIExpansionModel& expansionModel,
    std::size_t itemIndex);

UIEditorTreeViewLayout BuildUIEditorTreeViewLayout(
    const ::XCEngine::UI::UIRect& bounds,
    const std::vector<UIEditorTreeViewItem>& items,
    const ::XCEngine::UI::Widgets::UIExpansionModel& expansionModel,
    const UIEditorTreeViewMetrics& metrics = {});

UIEditorTreeViewHitTarget HitTestUIEditorTreeView(
    const UIEditorTreeViewLayout& layout,
    const ::XCEngine::UI::UIPoint& point);

void AppendUIEditorTreeViewBackground(
    ::XCEngine::UI::UIDrawList& drawList,
    const UIEditorTreeViewLayout& layout,
    const std::vector<UIEditorTreeViewItem>& items,
    const ::XCEngine::UI::Widgets::UISelectionModel& selectionModel,
    const UIEditorTreeViewState& state,
    const UIEditorTreeViewPalette& palette = {},
    const UIEditorTreeViewMetrics& metrics = {});

void AppendUIEditorTreeViewForeground(
    ::XCEngine::UI::UIDrawList& drawList,
    const UIEditorTreeViewLayout& layout,
    const std::vector<UIEditorTreeViewItem>& items,
    const UIEditorTreeViewPalette& palette = {},
    const UIEditorTreeViewMetrics& metrics = {});

void AppendUIEditorTreeView(
    ::XCEngine::UI::UIDrawList& drawList,
    const ::XCEngine::UI::UIRect& bounds,
    const std::vector<UIEditorTreeViewItem>& items,
    const ::XCEngine::UI::Widgets::UISelectionModel& selectionModel,
    const ::XCEngine::UI::Widgets::UIExpansionModel& expansionModel,
    const UIEditorTreeViewState& state,
    const UIEditorTreeViewPalette& palette = {},
    const UIEditorTreeViewMetrics& metrics = {});

} // namespace XCEngine::UI::Editor::Widgets