XCEngine/new_editor/include/XCEditor/Collections/UIEditorTabStrip.h

#pragma once

#include <XCEngine/UI/DrawData.h>
#include <XCEngine/UI/Layout/UITabStripLayout.h>
#include <XCEngine/UI/Widgets/UITabStripModel.h>

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

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

inline constexpr std::size_t UIEditorTabStripInvalidIndex =
    ::XCEngine::UI::Widgets::UITabStripModel::InvalidIndex;

struct UIEditorTabStripItem {
    std::string tabId = {};
    std::string title = {};
    bool closable = true;
    float desiredHeaderLabelWidth = 0.0f;
};

struct UIEditorTabStripReorderState {
    ::XCEngine::UI::UIPoint pressPosition = {};
    std::size_t pressedIndex = UIEditorTabStripInvalidIndex;
    std::size_t sourceIndex = UIEditorTabStripInvalidIndex;
    std::size_t previewInsertionIndex = UIEditorTabStripInvalidIndex;
    bool armed = false;
    bool dragging = false;
};

struct UIEditorTabStripState {
    std::size_t selectedIndex = UIEditorTabStripInvalidIndex;
    std::size_t hoveredIndex = UIEditorTabStripInvalidIndex;
    std::size_t closeHoveredIndex = UIEditorTabStripInvalidIndex;
    bool focused = false;
    UIEditorTabStripReorderState reorder = {};
};

struct UIEditorTabStripMetrics {
    ::XCEngine::UI::Layout::UITabStripMetrics layoutMetrics =
        ::XCEngine::UI::Layout::UITabStripMetrics{ 22.0f, 68.0f, 8.0f, 1.0f };
    float estimatedGlyphWidth = 6.0f;
    float closeButtonExtent = 10.0f;
    float closeButtonGap = 4.0f;
    float closeInsetRight = 6.0f;
    float closeInsetY = 0.0f;
    float labelInsetX = 8.0f;
    float labelInsetY = -0.5f;
    float baseBorderThickness = 1.0f;
    float selectedBorderThickness = 1.0f;
    float focusedBorderThickness = 1.0f;
    float reorderDragThreshold = 6.0f;
    float reorderPreviewThickness = 2.0f;
    float reorderPreviewInsetY = 3.0f;
};

struct UIEditorTabStripPalette {
    ::XCEngine::UI::UIColor stripBackgroundColor =
        ::XCEngine::UI::UIColor(0.18f, 0.18f, 0.18f, 1.0f);
    ::XCEngine::UI::UIColor headerBackgroundColor =
        ::XCEngine::UI::UIColor(0.18f, 0.18f, 0.18f, 1.0f);
    ::XCEngine::UI::UIColor contentBackgroundColor =
        ::XCEngine::UI::UIColor(0.18f, 0.18f, 0.18f, 1.0f);
    ::XCEngine::UI::UIColor stripBorderColor =
        ::XCEngine::UI::UIColor(0.24f, 0.24f, 0.24f, 1.0f);
    ::XCEngine::UI::UIColor headerContentSeparatorColor =
        ::XCEngine::UI::UIColor(0.27f, 0.27f, 0.27f, 1.0f);
    ::XCEngine::UI::UIColor focusedBorderColor =
        ::XCEngine::UI::UIColor(0.36f, 0.36f, 0.36f, 1.0f);
    ::XCEngine::UI::UIColor tabColor =
        ::XCEngine::UI::UIColor(0.20f, 0.20f, 0.20f, 1.0f);
    ::XCEngine::UI::UIColor tabHoveredColor =
        ::XCEngine::UI::UIColor(0.23f, 0.23f, 0.23f, 1.0f);
    ::XCEngine::UI::UIColor tabSelectedColor =
        ::XCEngine::UI::UIColor(0.18f, 0.18f, 0.18f, 1.0f);
    ::XCEngine::UI::UIColor tabBorderColor =
        ::XCEngine::UI::UIColor(0.24f, 0.24f, 0.24f, 1.0f);
    ::XCEngine::UI::UIColor tabHoveredBorderColor =
        ::XCEngine::UI::UIColor(0.31f, 0.31f, 0.31f, 1.0f);
    ::XCEngine::UI::UIColor tabSelectedBorderColor =
        ::XCEngine::UI::UIColor(0.34f, 0.34f, 0.34f, 1.0f);
    ::XCEngine::UI::UIColor textPrimary =
        ::XCEngine::UI::UIColor(0.86f, 0.86f, 0.86f, 1.0f);
    ::XCEngine::UI::UIColor textSecondary =
        ::XCEngine::UI::UIColor(0.67f, 0.67f, 0.67f, 1.0f);
    ::XCEngine::UI::UIColor textMuted =
        ::XCEngine::UI::UIColor(0.58f, 0.58f, 0.58f, 1.0f);
    ::XCEngine::UI::UIColor closeButtonColor =
        ::XCEngine::UI::UIColor(0.20f, 0.20f, 0.20f, 1.0f);
    ::XCEngine::UI::UIColor closeButtonHoveredColor =
        ::XCEngine::UI::UIColor(0.25f, 0.25f, 0.25f, 1.0f);
    ::XCEngine::UI::UIColor closeButtonBorderColor =
        ::XCEngine::UI::UIColor(0.30f, 0.30f, 0.30f, 1.0f);
    ::XCEngine::UI::UIColor closeGlyphColor =
        ::XCEngine::UI::UIColor(0.83f, 0.83f, 0.83f, 1.0f);
    ::XCEngine::UI::UIColor reorderPreviewColor =
        ::XCEngine::UI::UIColor(0.82f, 0.82f, 0.82f, 1.0f);
};

struct UIEditorTabStripInsertionPreview {
    bool visible = false;
    std::size_t insertionIndex = UIEditorTabStripInvalidIndex;
    ::XCEngine::UI::UIRect indicatorRect = {};
};

struct UIEditorTabStripLayout {
    ::XCEngine::UI::UIRect bounds = {};
    ::XCEngine::UI::UIRect headerRect = {};
    ::XCEngine::UI::UIRect contentRect = {};
    std::vector<::XCEngine::UI::UIRect> tabHeaderRects = {};
    std::vector<::XCEngine::UI::UIRect> closeButtonRects = {};
    std::vector<bool> showCloseButtons = {};
    std::size_t selectedIndex = UIEditorTabStripInvalidIndex;
    UIEditorTabStripInsertionPreview insertionPreview = {};
};

enum class UIEditorTabStripHitTargetKind : std::uint8_t {
    None = 0,
    HeaderBackground,
    Tab,
    CloseButton,
    Content
};

struct UIEditorTabStripHitTarget {
    UIEditorTabStripHitTargetKind kind = UIEditorTabStripHitTargetKind::None;
    std::size_t index = UIEditorTabStripInvalidIndex;
};

float ResolveUIEditorTabStripDesiredHeaderLabelWidth(
    const UIEditorTabStripItem& item,
    const UIEditorTabStripMetrics& metrics = {});

std::size_t ResolveUIEditorTabStripSelectedIndex(
    const std::vector<UIEditorTabStripItem>& items,
    std::string_view selectedTabId,
    std::size_t fallbackIndex = UIEditorTabStripInvalidIndex);

std::size_t ResolveUIEditorTabStripSelectedIndexAfterClose(
    std::size_t selectedIndex,
    std::size_t closedIndex,
    std::size_t itemCountBeforeClose);

UIEditorTabStripLayout BuildUIEditorTabStripLayout(
    const ::XCEngine::UI::UIRect& bounds,
    const std::vector<UIEditorTabStripItem>& items,
    const UIEditorTabStripState& state,
    const UIEditorTabStripMetrics& metrics = {});

UIEditorTabStripHitTarget HitTestUIEditorTabStrip(
    const UIEditorTabStripLayout& layout,
    const UIEditorTabStripState& state,
    const ::XCEngine::UI::UIPoint& point);

void AppendUIEditorTabStripBackground(
    ::XCEngine::UI::UIDrawList& drawList,
    const UIEditorTabStripLayout& layout,
    const UIEditorTabStripState& state,
    const UIEditorTabStripPalette& palette = {},
    const UIEditorTabStripMetrics& metrics = {});

void AppendUIEditorTabStripForeground(
    ::XCEngine::UI::UIDrawList& drawList,
    const UIEditorTabStripLayout& layout,
    const std::vector<UIEditorTabStripItem>& items,
    const UIEditorTabStripState& state,
    const UIEditorTabStripPalette& palette = {},
    const UIEditorTabStripMetrics& metrics = {});

void AppendUIEditorTabStrip(
    ::XCEngine::UI::UIDrawList& drawList,
    const ::XCEngine::UI::UIRect& bounds,
    const std::vector<UIEditorTabStripItem>& items,
    const UIEditorTabStripState& state,
    const UIEditorTabStripPalette& palette = {},
    const UIEditorTabStripMetrics& metrics = {});

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