path: root/src/brussel.engine/EditorUtils.cpp

#include "EditorUtils.hpp"

#define IMGUI_DEFINE_MATH_OPERATORS
#include <imgui_internal.h>

#include <backends/imgui_impl_glfw.h>
#include <cmath>
#define GLM_ENABLE_EXPERIMENTAL
#include <glm/gtc/quaternion.hpp>
#include <glm/gtx/quaternion.hpp>
#include <numbers>

const char* ImGui::GetKeyNameGlfw(int key) {
	return GetKeyName(ImGui_ImplGlfw_KeyToImGuiKey(key));
}

void ImGui::SetNextWindowSizeRelScreen(float xPercent, float yPercent, ImGuiCond cond) {
	auto vs = ImGui::GetMainViewport()->Size;
	ImGui::SetNextWindowSize({ vs.x * xPercent, vs.y * yPercent }, cond);
}

void ImGui::SetNextWindowCentered(ImGuiCond cond) {
	auto vs = ImGui::GetMainViewport()->Size;
	ImGui::SetNextWindowPos({ vs.x / 2, vs.y / 2 }, cond, { 0.5f, 0.5f });
}

void ImGui::PushDisabled() {
	ImGui::PushItemFlag(ImGuiItemFlags_Disabled, true);
	ImGui::PushStyleVar(ImGuiStyleVar_Alpha, 0.5f * ImGui::GetStyle().Alpha);
}

void ImGui::PopDisabled() {
	ImGui::PopItemFlag();
	ImGui::PopStyleVar();
}

bool ImGui::Button(const char* label, bool disabled) {
	return Button(label, ImVec2{}, disabled);
}

bool ImGui::Button(const char* label, const ImVec2& sizeArg, bool disabled) {
	if (disabled) PushDisabled();
	bool res = ImGui::Button(label, sizeArg);
	if (disabled) PopDisabled();

	return res;
}

#define EDIT_RGBA_COLOR(EditorFunction, kUsesAlpha)                        \
	float components[4];                                                   \
	components[0] = color->GetNormalizedRed();                             \
	components[1] = color->GetNormalizedGreen();                           \
	components[2] = color->GetNormalizedBlue();                            \
	if constexpr (kUsesAlpha) components[3] = color->GetNormalizedAlpha(); \
	if (EditorFunction(label, components, flags)) {                        \
		color->r = components[0] * 255;                                    \
		color->g = components[1] * 255;                                    \
		color->b = components[2] * 255;                                    \
		if constexpr (kUsesAlpha) color->a = components[3] * 255;          \
		return true;                                                       \
	} else {                                                               \
		return false;                                                      \
	}

bool ImGui::ColorEdit3(const char* label, RgbaColor* color, ImGuiColorEditFlags flags) {
	EDIT_RGBA_COLOR(ColorEdit3, false);
}

bool ImGui::ColorEdit4(const char* label, RgbaColor* color, ImGuiColorEditFlags flags) {
	EDIT_RGBA_COLOR(ColorEdit4, true);
}

bool ImGui::ColorPicker3(const char* label, RgbaColor* color, ImGuiColorEditFlags flags) {
	EDIT_RGBA_COLOR(ColorPicker3, false);
}

bool ImGui::ColorPicker4(const char* label, RgbaColor* color, ImGuiColorEditFlags flags) {
	EDIT_RGBA_COLOR(ColorPicker4, true);
}

#undef EDIT_RGBA_COLOR

struct InputTextCallbackUserData {
	std::string* str;
	ImGuiInputTextCallback chainCallback;
	void* chainCallbackUserData;
};

static int InputTextCallback(ImGuiInputTextCallbackData* data) {
	auto user_data = (InputTextCallbackUserData*)data->UserData;
	if (data->EventFlag == ImGuiInputTextFlags_CallbackResize) {
		// Resize string callback
		// If for some reason we refuse the new length (BufTextLen) and/or capacity (BufSize) we need to set them back to what we want.
		auto str = user_data->str;
		IM_ASSERT(data->Buf == str->c_str());
		str->resize(data->BufTextLen);
		data->Buf = (char*)str->c_str();
	} else if (user_data->chainCallback) {
		// Forward to user callback, if any
		data->UserData = user_data->chainCallbackUserData;
		return user_data->chainCallback(data);
	}
	return 0;
}

bool ImGui::Splitter(bool splitVertically, float thickness, float* size1, float* size2, float minSize1, float minSize2, float splitterLongAxisSize) {
	// Adapted from https://github.com/thedmd/imgui-node-editor/blob/master/examples/blueprints-example/blueprints-example.cpp
	// ::Splitter

	ImGuiContext& g = *GImGui;
	ImGuiWindow* window = g.CurrentWindow;
	ImGuiID id = window->GetID("##Splitter");
	ImRect bb;
	bb.Min = window->DC.CursorPos + (splitVertically ? ImVec2(*size1, 0.0f) : ImVec2(0.0f, *size1));
	bb.Max = bb.Min + CalcItemSize(splitVertically ? ImVec2(thickness, splitterLongAxisSize) : ImVec2(splitterLongAxisSize, thickness), 0.0f, 0.0f);

	// Adapted from ImGui::SplitterBehavior, changes:
	// - Simplified unneeded logic (hover_extend and hover_visibility_delay)
	// - Changed clamped delta to clamping result size1 and deriving size2 from size1, allowing automatically adapting to the latest window content region width

	auto itemFlagsBackup = g.CurrentItemFlags;
	g.CurrentItemFlags |= ImGuiItemFlags_NoNav | ImGuiItemFlags_NoNavDefaultFocus;
	bool itemAdd = ItemAdd(bb, id);
	g.CurrentItemFlags = itemFlagsBackup;
	if (!itemAdd) {
		return false;
	}

	bool hovered, held;
	auto bbInteract = bb;
	ButtonBehavior(bbInteract, id, &hovered, &held, ImGuiButtonFlags_FlattenChildren | ImGuiButtonFlags_AllowItemOverlap);
	if (hovered) {
		g.LastItemData.StatusFlags |= ImGuiItemStatusFlags_HoveredRect;
	} // for IsItemHovered(), because bbInteract is larger than bb
	if (g.ActiveId != id) {
		SetItemAllowOverlap();
	}

	if (held || (hovered && g.HoveredIdPreviousFrame == id && g.HoveredIdTimer >= 0.0f)) {
		SetMouseCursor((splitVertically ? ImGuiAxis_X : ImGuiAxis_Y) == ImGuiAxis_Y ? ImGuiMouseCursor_ResizeNS : ImGuiMouseCursor_ResizeEW);
	}

	float contentSize = splitVertically ? window->ContentRegionRect.GetWidth() : window->ContentRegionRect.GetHeight();
	if (held) {
		ImVec2 mouseDelta2D = g.IO.MousePos - g.ActiveIdClickOffset - bbInteract.Min;
		float mouseDelta = ((splitVertically ? ImGuiAxis_X : ImGuiAxis_Y) == ImGuiAxis_Y) ? mouseDelta2D.y : mouseDelta2D.x;

		// Apply resize
		if (mouseDelta != 0.0f) {
			*size1 = ImClamp(*size1 + mouseDelta, minSize1, contentSize - minSize2 - thickness);
			*size2 = contentSize - *size1 - thickness;
			MarkItemEdited(id);
		}
	}

	ImU32 col;
	if (held) {
		col = GetColorU32(ImGuiCol_SeparatorActive);
	} else if (hovered && g.HoveredIdTimer >= 0.0f) {
		col = GetColorU32(ImGuiCol_SeparatorHovered);
	} else {
		col = GetColorU32(ImGuiCol_Separator);
	}
	window->DrawList->AddRectFilled(bb.Min, bb.Max, col, 0.0f);

	return held;
}

void ImGui::AddUnderLine(ImColor col) {
	auto min = ImGui::GetItemRectMin();
	auto max = ImGui::GetItemRectMax();
	min.y = max.y;
	ImGui::GetWindowDrawList()->AddLine(min, max, col, 1.0f);
}

void ImGui::DrawIcon(ImDrawList* drawList, const ImVec2& a, const ImVec2& b, IconType type, bool filled, ImU32 color, ImU32 innerColor) {
	// Taken from https://github.com/thedmd/imgui-node-editor/blob/master/examples/blueprints-example/utilities/drawing.cpp
	// ax::NodeEditor::DrawIcon

	auto rect = ImRect(a, b);
	auto rect_x = rect.Min.x;
	auto rect_y = rect.Min.y;
	auto rect_w = rect.Max.x - rect.Min.x;
	auto rect_h = rect.Max.y - rect.Min.y;
	auto rect_center_x = (rect.Min.x + rect.Max.x) * 0.5f;
	auto rect_center_y = (rect.Min.y + rect.Max.y) * 0.5f;
	auto rect_center = ImVec2(rect_center_x, rect_center_y);
	const auto outline_scale = rect_w / 24.0f;
	const auto extra_segments = static_cast<int>(2 * outline_scale); // for full circle

	if (type == IconType::Flow) {
		const auto origin_scale = rect_w / 24.0f;

		const auto offset_x = 1.0f * origin_scale;
		const auto offset_y = 0.0f * origin_scale;
		const auto margin = 2.0f * origin_scale;
		const auto rounding = 0.1f * origin_scale;
		const auto tip_round = 0.7f; // percentage of triangle edge (for tip)
		// const auto edge_round = 0.7f; // percentage of triangle edge (for corner)
		const auto canvas = ImRect(
			rect.Min.x + margin + offset_x,
			rect.Min.y + margin + offset_y,
			rect.Max.x - margin + offset_x,
			rect.Max.y - margin + offset_y);
		const auto canvas_x = canvas.Min.x;
		const auto canvas_y = canvas.Min.y;
		const auto canvas_w = canvas.Max.x - canvas.Min.x;
		const auto canvas_h = canvas.Max.y - canvas.Min.y;

		const auto left = canvas_x + canvas_w * 0.5f * 0.3f;
		const auto right = canvas_x + canvas_w - canvas_w * 0.5f * 0.3f;
		const auto top = canvas_y + canvas_h * 0.5f * 0.2f;
		const auto bottom = canvas_y + canvas_h - canvas_h * 0.5f * 0.2f;
		const auto center_y = (top + bottom) * 0.5f;
		// const auto angle = AX_PI * 0.5f * 0.5f * 0.5f;

		const auto tip_top = ImVec2(canvas_x + canvas_w * 0.5f, top);
		const auto tip_right = ImVec2(right, center_y);
		const auto tip_bottom = ImVec2(canvas_x + canvas_w * 0.5f, bottom);

		drawList->PathLineTo(ImVec2(left, top) + ImVec2(0, rounding));
		drawList->PathBezierCubicCurveTo(
			ImVec2(left, top),
			ImVec2(left, top),
			ImVec2(left, top) + ImVec2(rounding, 0));
		drawList->PathLineTo(tip_top);
		drawList->PathLineTo(tip_top + (tip_right - tip_top) * tip_round);
		drawList->PathBezierCubicCurveTo(
			tip_right,
			tip_right,
			tip_bottom + (tip_right - tip_bottom) * tip_round);
		drawList->PathLineTo(tip_bottom);
		drawList->PathLineTo(ImVec2(left, bottom) + ImVec2(rounding, 0));
		drawList->PathBezierCubicCurveTo(
			ImVec2(left, bottom),
			ImVec2(left, bottom),
			ImVec2(left, bottom) - ImVec2(0, rounding));

		if (!filled) {
			if (innerColor & 0xFF000000) {
				drawList->AddConvexPolyFilled(drawList->_Path.Data, drawList->_Path.Size, innerColor);
			}

			drawList->PathStroke(color, true, 2.0f * outline_scale);
		} else {
			drawList->PathFillConvex(color);
		}
	} else {
		auto triangleStart = rect_center_x + 0.32f * rect_w;

		auto rect_offset = -static_cast<int>(rect_w * 0.25f * 0.25f);

		rect.Min.x += rect_offset;
		rect.Max.x += rect_offset;
		rect_x += rect_offset;
		rect_center_x += rect_offset * 0.5f;
		rect_center.x += rect_offset * 0.5f;

		if (type == IconType::Circle) {
			const auto c = rect_center;

			if (!filled) {
				const auto r = 0.5f * rect_w / 2.0f - 0.5f;

				if (innerColor & 0xFF000000)
					drawList->AddCircleFilled(c, r, innerColor, 12 + extra_segments);
				drawList->AddCircle(c, r, color, 12 + extra_segments, 2.0f * outline_scale);
			} else {
				drawList->AddCircleFilled(c, 0.5f * rect_w / 2.0f, color, 12 + extra_segments);
			}
		}

		if (type == IconType::Square) {
			if (filled) {
				const auto r = 0.5f * rect_w / 2.0f;
				const auto p0 = rect_center - ImVec2(r, r);
				const auto p1 = rect_center + ImVec2(r, r);

				drawList->AddRectFilled(p0, p1, color, 0, 15 + extra_segments);
			} else {
				const auto r = 0.5f * rect_w / 2.0f - 0.5f;
				const auto p0 = rect_center - ImVec2(r, r);
				const auto p1 = rect_center + ImVec2(r, r);

				if (innerColor & 0xFF000000)
					drawList->AddRectFilled(p0, p1, innerColor, 0, 15 + extra_segments);

				drawList->AddRect(p0, p1, color, 0, 15 + extra_segments, 2.0f * outline_scale);
			}
		}

		if (type == IconType::Grid) {
			const auto r = 0.5f * rect_w / 2.0f;
			const auto w = ceilf(r / 3.0f);

			const auto baseTl = ImVec2(floorf(rect_center_x - w * 2.5f), floorf(rect_center_y - w * 2.5f));
			const auto baseBr = ImVec2(floorf(baseTl.x + w), floorf(baseTl.y + w));

			auto tl = baseTl;
			auto br = baseBr;
			for (int i = 0; i < 3; ++i) {
				tl.x = baseTl.x;
				br.x = baseBr.x;
				drawList->AddRectFilled(tl, br, color);
				tl.x += w * 2;
				br.x += w * 2;
				if (i != 1 || filled)
					drawList->AddRectFilled(tl, br, color);
				tl.x += w * 2;
				br.x += w * 2;
				drawList->AddRectFilled(tl, br, color);

				tl.y += w * 2;
				br.y += w * 2;
			}

			triangleStart = br.x + w + 1.0f / 24.0f * rect_w;
		}

		if (type == IconType::RoundSquare) {
			if (filled) {
				const auto r = 0.5f * rect_w / 2.0f;
				const auto cr = r * 0.5f;
				const auto p0 = rect_center - ImVec2(r, r);
				const auto p1 = rect_center + ImVec2(r, r);

				drawList->AddRectFilled(p0, p1, color, cr, 15);
			} else {
				const auto r = 0.5f * rect_w / 2.0f - 0.5f;
				const auto cr = r * 0.5f;
				const auto p0 = rect_center - ImVec2(r, r);
				const auto p1 = rect_center + ImVec2(r, r);

				if (innerColor & 0xFF000000)
					drawList->AddRectFilled(p0, p1, innerColor, cr, 15);

				drawList->AddRect(p0, p1, color, cr, 15, 2.0f * outline_scale);
			}
		} else if (type == IconType::Diamond) {
			if (filled) {
				const auto r = 0.607f * rect_w / 2.0f;
				const auto c = rect_center;

				drawList->PathLineTo(c + ImVec2(0, -r));
				drawList->PathLineTo(c + ImVec2(r, 0));
				drawList->PathLineTo(c + ImVec2(0, r));
				drawList->PathLineTo(c + ImVec2(-r, 0));
				drawList->PathFillConvex(color);
			} else {
				const auto r = 0.607f * rect_w / 2.0f - 0.5f;
				const auto c = rect_center;

				drawList->PathLineTo(c + ImVec2(0, -r));
				drawList->PathLineTo(c + ImVec2(r, 0));
				drawList->PathLineTo(c + ImVec2(0, r));
				drawList->PathLineTo(c + ImVec2(-r, 0));

				if (innerColor & 0xFF000000)
					drawList->AddConvexPolyFilled(drawList->_Path.Data, drawList->_Path.Size, innerColor);

				drawList->PathStroke(color, true, 2.0f * outline_scale);
			}
		} else {
			const auto triangleTip = triangleStart + rect_w * (0.45f - 0.32f);

			drawList->AddTriangleFilled(
				ImVec2(ceilf(triangleTip), rect_y + rect_h * 0.5f),
				ImVec2(triangleStart, rect_center_y + 0.15f * rect_h),
				ImVec2(triangleStart, rect_center_y - 0.15f * rect_h),
				color);
		}
	}
}

void ImGui::Icon(const ImVec2& size, IconType type, bool filled, const ImVec4& color, const ImVec4& innerColor) {
	// Taken from https://github.com/thedmd/imgui-node-editor/blob/master/examples/blueprints-example/utilities/widgets.cpp
	// ax::NodeEditor::Icon

	if (ImGui::IsRectVisible(size)) {
		auto cursorPos = ImGui::GetCursorScreenPos();
		auto drawList = ImGui::GetWindowDrawList();
		DrawIcon(drawList, cursorPos, cursorPos + size, type, filled, ImColor(color), ImColor(innerColor));
	}

	ImGui::Dummy(size);
}

void ImGui::DrawArrow(ImDrawList* drawList, ImVec2 from, ImVec2 to, ImU32 color, float lineThickness) {
	// Adapted from https://stackoverflow.com/a/6333775

	using namespace std::numbers;
	constexpr float kHeadLength = 10;

	auto angle = std::atan2(to.y - from.y, to.x - from.x);
	drawList->AddLine(from, to, color, lineThickness);
	drawList->AddLine(to, ImVec2(to.x - kHeadLength * std::cos(angle - pi / 6), to.y - kHeadLength * std::sin(angle - pi / 6)), color, lineThickness);
	drawList->AddLine(to, ImVec2(to.x - kHeadLength * std::cos(angle + pi / 6), to.y - kHeadLength * std::sin(angle + pi / 6)), color, lineThickness);
}

struct DialogObject {
	std::string message;
	std::function<void(int)> callback;
};

static DialogObject gConfirmationDialog{};

void ImGui::DialogConfirmation(std::string message, std::function<void(bool)> callback) {
	gConfirmationDialog.message = std::move(message);
	// TODO is converting void(bool) to void(int) fine?
	gConfirmationDialog.callback = std::move(callback);
}

void ImGui::ShowDialogs() {
	if (gConfirmationDialog.callback) {
		if (ImGui::BeginPopupModal("Confirmation")) {
			ImGui::Text("%s", gConfirmationDialog.message.c_str());
			if (ImGui::Button("Cancel")) {
				gConfirmationDialog.callback(false);
				gConfirmationDialog.callback = {};
				ImGui::CloseCurrentPopup();
			}
			ImGui::SameLine();
			if (ImGui::Button("Confirm")) {
				gConfirmationDialog.callback(true);
				gConfirmationDialog.callback = {};
				ImGui::CloseCurrentPopup();
			}
			ImGui::EndPopup();
		}
	}
}

float Utils::CalcImageHeight(glm::vec2 original, int targetWidth) {
	// Xorig / Yorig = Xnew / Ynew
	//          Ynew = Xnew * Yorig / Xorig
	return targetWidth * original.y / original.x;
}

float Utils::CalcImageWidth(glm::vec2 original, float targetHeight) {
	// Xorig / Yorig = Xnew / Ynew
	//          Xnew = Xorig / Yorig * Ynew
	return original.x / original.y * targetHeight;
}

ImVec2 Utils::FitImage(glm::vec2 original) {
	float newWidth = ImGui::GetContentRegionAvail().x;
	return ImVec2(newWidth, CalcImageHeight(original, newWidth));
}