XCEngine/editor/src/UI/Widgets.h

#pragma once

#include "Core.h"
#include "StyleTokens.h"

#include <imgui.h>
#include <string>

namespace XCEngine {
namespace Editor {
namespace UI {

struct ComponentSectionResult {
    bool open = false;
    float contentIndent = 0.0f;
};

struct AssetTileResult {
    bool clicked = false;
    bool contextRequested = false;
    bool openRequested = false;
    bool hovered = false;
    ImVec2 min = ImVec2(0.0f, 0.0f);
    ImVec2 max = ImVec2(0.0f, 0.0f);
};

struct AssetTileOptions {
    ImVec2 size = AssetTileSize();
    ImVec2 iconOffset = AssetTileIconOffset();
    ImVec2 iconSize = AssetTileIconSize();
    bool drawIdleFrame = true;
    bool drawSelectionBorder = true;
};

enum class DialogActionResult {
    None,
    Primary,
    Secondary
};

enum class MenuCommandKind {
    Action,
    Separator
};

struct MenuCommand {
    MenuCommandKind kind = MenuCommandKind::Action;
    const char* label = nullptr;
    const char* shortcut = nullptr;
    bool selected = false;
    bool enabled = true;

    static MenuCommand Action(
        const char* label,
        const char* shortcut = nullptr,
        bool selected = false,
        bool enabled = true) {
        return MenuCommand{ MenuCommandKind::Action, label, shortcut, selected, enabled };
    }

    static MenuCommand Separator() {
        return MenuCommand{ MenuCommandKind::Separator, nullptr, nullptr, false, true };
    }
};

template <typename DrawContentFn>
inline bool DrawMenuScope(const char* label, DrawContentFn&& drawContent) {
    PushPopupWindowChrome();
    if (!ImGui::BeginMenu(label)) {
        PopPopupWindowChrome();
        return false;
    }
    PopPopupWindowChrome();

    PushPopupContentChrome();
    drawContent();
    PopPopupContentChrome();
    ImGui::EndMenu();
    return true;
}

template <typename ExecuteFn>
inline bool DrawMenuCommand(const MenuCommand& command, ExecuteFn&& execute) {
    if (command.kind == MenuCommandKind::Separator) {
        ImGui::Separator();
        return false;
    }

    if (!ImGui::MenuItem(command.label, command.shortcut, command.selected, command.enabled)) {
        return false;
    }

    execute();
    return true;
}

template <size_t N, typename ExecuteFn>
inline void DrawMenuCommands(const MenuCommand (&commands)[N], ExecuteFn&& execute) {
    for (size_t i = 0; i < N; ++i) {
        DrawMenuCommand(commands[i], [&]() { execute(i); });
    }
}

inline bool ToolbarSearchField(
    const char* id,
    const char* hint,
    char* buffer,
    size_t bufferSize,
    float trailingWidth = 0.0f) {
    ImGui::PushStyleVar(ImGuiStyleVar_FramePadding, SearchFieldFramePadding());
    ImGui::PushStyleVar(ImGuiStyleVar_FrameRounding, SearchFieldFrameRounding());
    const float width = ImGui::GetContentRegionAvail().x - trailingWidth;
    ImGui::SetNextItemWidth(width > 0.0f ? width : 0.0f);
    const bool changed = ImGui::InputTextWithHint(id, hint, buffer, bufferSize);
    ImGui::PopStyleVar(2);
    return changed;
}

inline void DrawToolbarLabel(const char* text) {
    ImGui::AlignTextToFramePadding();
    ImGui::TextColored(HintTextColor(), "%s", text);
}

inline bool ToolbarToggleButton(const char* label, bool& active, ImVec2 size = ImVec2(0.0f, 0.0f)) {
    if (!ToolbarButton(label, active, size)) {
        return false;
    }

    active = !active;
    return true;
}

inline void DrawToolbarRowGap() {
    ImGui::Dummy(ImVec2(0.0f, ToolbarRowGap()));
}

inline void DrawHintText(const char* text) {
    ImGui::TextColored(HintTextColor(), "%s", text);
}

inline void DrawEmptyState(
    const char* title,
    const char* subtitle = nullptr,
    ImVec2 start = ImVec2(10.0f, 10.0f)) {
    ImGui::SetCursorPos(start);
    ImGui::TextUnformatted(title);

    if (subtitle && subtitle[0] != '\0') {
        ImGui::SetCursorPos(ImVec2(start.x, start.y + EmptyStateLineOffset()));
        ImGui::TextColored(EmptyStateSubtitleColor(), "%s", subtitle);
    }
}

inline float BreadcrumbItemHeight() {
    return ImGui::GetTextLineHeight() + BreadcrumbSegmentPadding().y * 2.0f;
}

inline void DrawBreadcrumbTextItem(
    const char* label,
    const ImVec2& size,
    const ImVec4& color,
    bool clickable,
    bool* pressed = nullptr,
    bool* hovered = nullptr) {
    bool localPressed = false;
    if (clickable) {
        localPressed = ImGui::InvisibleButton("##BreadcrumbItem", size);
    } else {
        ImGui::Dummy(size);
    }
    const bool localHovered = clickable && ImGui::IsItemHovered();

    const ImVec2 itemMin = ImGui::GetItemRectMin();
    const ImVec2 itemMax = ImGui::GetItemRectMax();
    const ImVec2 textSize = ImGui::CalcTextSize(label);
    const float textX = itemMin.x + (size.x - textSize.x) * 0.5f;
    const float textY = itemMin.y + (itemMax.y - itemMin.y - textSize.y) * 0.5f;

    ImGui::GetWindowDrawList()->AddText(
        ImVec2(textX, textY),
        ImGui::GetColorU32(color),
        label);

    if (pressed) {
        *pressed = localPressed;
    }
    if (hovered) {
        *hovered = localHovered;
    }
}

inline bool DrawBreadcrumbSegment(const char* label, bool clickable, bool current = false) {
    if (!label || label[0] == '\0') {
        return false;
    }

    const ImVec2 padding = BreadcrumbSegmentPadding();
    const ImVec2 textSize = ImGui::CalcTextSize(label);
    const ImVec2 size(textSize.x + padding.x * 2.0f, BreadcrumbItemHeight());
    bool pressed = false;
    bool hovered = false;
    DrawBreadcrumbTextItem(label, size, BreadcrumbSegmentTextColor(current, hovered), clickable, &pressed, &hovered);

    if (hovered) {
        const ImVec2 itemMin = ImGui::GetItemRectMin();
        const ImVec2 itemMax = ImGui::GetItemRectMax();
        const ImVec2 textOnlySize = ImGui::CalcTextSize(label);
        const float textX = itemMin.x + (size.x - textOnlySize.x) * 0.5f;
        const float textY = itemMin.y + (itemMax.y - itemMin.y - textOnlySize.y) * 0.5f;
        ImGui::GetWindowDrawList()->AddText(
            ImVec2(textX, textY),
            ImGui::GetColorU32(BreadcrumbSegmentTextColor(current, true)),
            label);
    }

    return pressed;
}

inline void DrawBreadcrumbSeparator(const char* label = ">") {
    const ImVec2 textSize = ImGui::CalcTextSize(label);
    DrawBreadcrumbTextItem(label, ImVec2(textSize.x, BreadcrumbItemHeight()), BreadcrumbSeparatorColor(), false);
}

template <typename GetNameFn, typename NavigateFn>
inline void DrawToolbarBreadcrumbs(
    const char* rootLabel,
    size_t segmentCount,
    GetNameFn&& getName,
    NavigateFn&& navigateToSegment) {
    if (segmentCount == 0) {
        DrawBreadcrumbSegment(rootLabel, false, true);
        return;
    }

    for (size_t i = 0; i < segmentCount; ++i) {
        if (i > 0) {
            ImGui::SameLine(0.0f, BreadcrumbSegmentSpacing());
            DrawBreadcrumbSeparator();
            ImGui::SameLine(0.0f, BreadcrumbSegmentSpacing());
        }

        const std::string label = (i == 0 && rootLabel && rootLabel[0] != '\0')
            ? std::string(rootLabel)
            : getName(i);
        const bool current = (i + 1 == segmentCount);

        ImGui::PushID(static_cast<int>(i));
        if (DrawBreadcrumbSegment(label.c_str(), !current, current)) {
            navigateToSegment(i);
        }
        ImGui::PopID();
    }
}

template <typename DrawIconFn>
inline AssetTileResult DrawAssetTile(
    const char* label,
    bool selected,
    bool dimmed,
    DrawIconFn&& drawIcon,
    const AssetTileOptions& options = AssetTileOptions()) {
    const ImVec2 textSize = ImGui::CalcTextSize(label);
    ImVec2 tileSize = options.size;
    tileSize.x = std::max(tileSize.x, options.iconSize.x + AssetTileTextPadding().x * 2.0f);
    tileSize.y = std::max(
        tileSize.y,
        options.iconOffset.y +
            options.iconSize.y +
            AssetTileIconTextGap() +
            textSize.y +
            AssetTileTextPadding().y);
    ImGui::InvisibleButton("##AssetBtn", tileSize);

    const bool clicked = ImGui::IsItemClicked(ImGuiMouseButton_Left);
    const bool contextRequested = ImGui::IsItemClicked(ImGuiMouseButton_Right);
    const bool openRequested = ImGui::IsItemHovered() && ImGui::IsMouseDoubleClicked(0);
    const bool hovered = ImGui::IsItemHovered(ImGuiHoveredFlags_AllowWhenBlockedByActiveItem);

    const ImVec2 min = ImGui::GetItemRectMin();
    const ImVec2 max = ImVec2(min.x + tileSize.x, min.y + tileSize.y);
    ImDrawList* drawList = ImGui::GetWindowDrawList();

    if (options.drawIdleFrame) {
        drawList->AddRectFilled(min, max, ImGui::GetColorU32(AssetTileIdleFillColor()), AssetTileRounding());
        drawList->AddRect(min, max, ImGui::GetColorU32(AssetTileIdleBorderColor()), AssetTileRounding());
    }

    if (hovered || selected) {
        drawList->AddRectFilled(min, max, ImGui::GetColorU32(selected ? AssetTileSelectedFillColor() : AssetTileHoverFillColor()), AssetTileRounding());
    }
    if (selected && options.drawSelectionBorder) {
        drawList->AddRect(min, max, ImGui::GetColorU32(AssetTileSelectedBorderColor()), AssetTileRounding());
    }
    if (dimmed) {
        drawList->AddRectFilled(min, max, ImGui::GetColorU32(AssetTileDraggedOverlayColor()), 0.0f);
    }

    const ImVec2 iconMin(
        min.x + (tileSize.x - options.iconSize.x) * 0.5f,
        min.y + options.iconOffset.y);
    const ImVec2 iconMax(iconMin.x + options.iconSize.x, iconMin.y + options.iconSize.y);
    drawIcon(drawList, iconMin, iconMax);

    const ImVec2 textPadding = AssetTileTextPadding();
    const float textAreaWidth = tileSize.x - textPadding.x * 2.0f;
    const float centeredTextX = min.x + textPadding.x + std::max(0.0f, (textAreaWidth - textSize.x) * 0.5f);
    const float textY = max.y - textSize.y - AssetTileTextPadding().y;
    ImGui::PushClipRect(ImVec2(min.x + textPadding.x, min.y), ImVec2(max.x - textPadding.x, max.y), true);
    drawList->AddText(ImVec2(centeredTextX, textY), ImGui::GetColorU32(AssetTileTextColor(selected)), label);
    ImGui::PopClipRect();

    return AssetTileResult{ clicked, contextRequested, openRequested, hovered, min, max };
}

template <typename DrawMenuFn>
inline ComponentSectionResult BeginComponentSection(
    const void* id,
    const char* label,
    DrawMenuFn&& drawMenu,
    bool defaultOpen = true) {
    const ImGuiStyle& style = ImGui::GetStyle();
    const ImVec2 framePadding = InspectorSectionFramePadding();
    const float availableWidth = ImMax(ImGui::GetContentRegionAvail().x, 1.0f);
    const float arrowSlotWidth = ImGui::GetTreeNodeToLabelSpacing();
    const ImVec2 labelSize = ImGui::CalcTextSize(label ? label : "", nullptr, false);
    const float rowHeight = ImMax(labelSize.y, ImGui::GetFontSize()) + framePadding.y * 2.0f;

    ImGui::PushID(id);
    const ImGuiID openStateId = ImGui::GetID("##ComponentSectionOpen");
    ImGuiStorage* storage = ImGui::GetStateStorage();
    bool open = storage->GetBool(openStateId, defaultOpen);

    ImGui::PushStyleVar(ImGuiStyleVar_ItemSpacing, ImVec2(style.ItemSpacing.x, InspectorSectionItemSpacing().y));
    ImGui::InvisibleButton("##ComponentSectionHeader", ImVec2(availableWidth, rowHeight));
    ImGui::PopStyleVar();

    const bool hovered = ImGui::IsItemHovered(ImGuiHoveredFlags_AllowWhenBlockedByActiveItem);
    const bool held = ImGui::IsItemActive();
    if (ImGui::IsItemClicked(ImGuiMouseButton_Left)) {
        open = !open;
        storage->SetBool(openStateId, open);
    }

    const ImVec2 itemMin = ImGui::GetItemRectMin();
    const ImVec2 itemMax = ImGui::GetItemRectMax();
    const ImRect frameRect(itemMin, itemMax);
    const ImRect arrowRect(
        ImVec2(itemMin.x + framePadding.x, itemMin.y),
        ImVec2(itemMin.x + arrowSlotWidth, itemMax.y));

    ImDrawList* drawList = ImGui::GetWindowDrawList();
    const ImU32 bgColor = ImGui::GetColorU32(
        (held && hovered) ? ImGuiCol_HeaderActive :
        hovered ? ImGuiCol_HeaderHovered :
        ImGuiCol_Header);
    drawList->AddRectFilled(frameRect.Min, frameRect.Max, bgColor, style.FrameRounding);
    if (style.FrameBorderSize > 0.0f) {
        drawList->AddRect(
            frameRect.Min,
            frameRect.Max,
            ImGui::GetColorU32(ImGuiCol_Border),
            style.FrameRounding,
            0,
            style.FrameBorderSize);
    }

    DrawDisclosureArrow(drawList, arrowRect.Min, arrowRect.Max, open, ImGui::GetColorU32(ImGuiCol_Text));

    if (label && label[0] != '\0') {
        const float textX = itemMin.x + arrowSlotWidth;
        const float textY = itemMin.y + ((itemMax.y - itemMin.y) - labelSize.y) * 0.5f;
        drawList->PushClipRect(ImVec2(textX, itemMin.y), itemMax, true);
        drawList->AddText(ImVec2(textX, textY), ImGui::GetColorU32(ImGuiCol_Text), label);
        drawList->PopClipRect();
    }

    if (BeginPopupContextItem("##ComponentSettings")) {
        drawMenu();
        EndPopup();
    }

    ImGui::PopID();
    return ComponentSectionResult{ open, InspectorSectionContentIndent() };
}

inline ComponentSectionResult BeginComponentSection(
    const void* id,
    const char* label,
    bool defaultOpen = true) {
    return BeginComponentSection(id, label, []() {}, defaultOpen);
}

inline void EndComponentSection(const ComponentSectionResult& section) {
    if (section.open && section.contentIndent > 0.0f) {
        ImGui::Unindent(section.contentIndent);
    }
}

inline bool InspectorActionButton(const char* label, ImVec2 size = ImVec2(-1.0f, 0.0f)) {
    ImGui::PushStyleVar(ImGuiStyleVar_FramePadding, InspectorActionButtonPadding());
    const bool pressed = ImGui::Button(label, size);
    ImGui::PopStyleVar();
    return pressed;
}

inline bool BeginTitledPopup(const char* id, const char* title) {
    const bool open = BeginPopup(id);
    if (!open) {
        return false;
    }

    if (title && title[0] != '\0') {
        ImGui::TextUnformatted(title);
        ImGui::Separator();
    }

    return true;
}

inline void EndTitledPopup() {
    EndPopup();
}

inline DialogActionResult DrawDialogActionRow(
    const char* primaryLabel,
    const char* secondaryLabel,
    bool primaryEnabled = true,
    bool secondaryEnabled = true) {
    DialogActionResult result = DialogActionResult::None;

    ImGui::BeginDisabled(!primaryEnabled);
    if (ImGui::Button(primaryLabel, DialogActionButtonSize())) {
        result = DialogActionResult::Primary;
    }
    ImGui::EndDisabled();

    ImGui::SameLine();

    ImGui::BeginDisabled(!secondaryEnabled);
    if (ImGui::Button(secondaryLabel, DialogActionButtonSize())) {
        result = DialogActionResult::Secondary;
    }
    ImGui::EndDisabled();

    return result;
}

inline void DrawRightAlignedText(const char* text, const ImVec4& color, float rightPadding = MenuBarStatusRightPadding()) {
    const ImVec2 textSize = ImGui::CalcTextSize(text);
    const float targetX = ImGui::GetWindowWidth() - textSize.x - rightPadding;
    if (targetX > ImGui::GetCursorPosX()) {
        ImGui::SetCursorPosX(targetX);
    }
    ImGui::TextColored(color, "%s", text);
}

inline void BeginTitledTooltip(const char* title) {
    ImGui::BeginTooltip();
    if (title && title[0] != '\0') {
        ImGui::TextUnformatted(title);
        ImGui::Separator();
    }
}

inline void EndTitledTooltip() {
    ImGui::EndTooltip();
}

inline bool DrawConsoleLogRow(const char* text) {
    ImGui::TextUnformatted(text);

    if (ImGui::IsItemHovered()) {
        ImDrawList* drawList = ImGui::GetWindowDrawList();
        drawList->AddRectFilled(ImGui::GetItemRectMin(), ImGui::GetItemRectMax(), ImGui::GetColorU32(ConsoleRowHoverFillColor()));
    }

    return ImGui::IsItemClicked();
}

}
}
}