#include <sstream>

#include "Renderer.h"
#include "imgui\imgui_internal.h"


Renderer* Renderer::_instance = NULL;

Renderer::Renderer() : inFrame(false)
{

}

Renderer::~Renderer()
{

}

Renderer* Renderer::Get()
{
	if (!_instance)
	{
		_instance = new Renderer();
	}
	return _instance;
}

void Renderer::BeginScene()
{
	ImGuiIO& io = ImGui::GetIO();
	ImGui::PushStyleVar(ImGuiStyleVar_WindowBorderSize, 0.0f);
	ImGui::PushStyleVar(ImGuiStyleVar_WindowPadding, { 0.0f, 0.0f });
	ImGui::PushStyleColor(ImGuiCol_WindowBg, { 0.0f, 0.0f, 0.0f, 0.0f });
	ImGui::Begin("##Backbuffer", nullptr, ImGuiWindowFlags_NoTitleBar | ImGuiWindowFlags_NoInputs);
	ImGui::SetWindowPos(ImVec2(0, 0), ImGuiCond_Always);
	ImGui::SetWindowSize(ImVec2(io.DisplaySize.x, io.DisplaySize.y), ImGuiCond_Always);
	inFrame = true;
}

void Renderer::EndScene()
{
	ImGuiWindow* window = ImGui::GetCurrentWindow();
	window->DrawList->PushClipRectFullScreen();

	ImGui::End();
	ImGui::PopStyleColor();
	ImGui::PopStyleVar(2);
	inFrame = false;
}

void Renderer::RenderText(const std::string& text, const ImVec2& position, float size, uint32_t color, bool center)
{
	ImGuiWindow* window = ImGui::GetCurrentWindow();

	float a = (color >> 24) & 0xff;
	float r = (color >> 16) & 0xff;
	float g = (color >> 8) & 0xff;
	float b = (color) & 0xff;

	if (center)
	{
		window->DrawList->AddText(NULL, size, position, ImGui::GetColorU32({ r, g, b, a }), text.c_str());
	}
	else
	{
		window->DrawList->AddText(NULL, size, position, ImGui::GetColorU32({ r,g,b,a }), text.c_str());
	}
}

void Renderer::RenderLine(const ImVec2& from, const ImVec2& to, uint32_t color, float thickness)
{
	ImGuiWindow* window = ImGui::GetCurrentWindow();

	float a = (color >> 24) & 0xff;
	float r = (color >> 16) & 0xff;
	float g = (color >> 8) & 0xff;
	float b = (color) & 0xff;

	window->DrawList->AddLine(from, to, ImGui::GetColorU32({ r / 255.0f, g / 255.0f, b / 255.0f, a / 255.0f }), thickness);
}

void Renderer::RenderPolygon(const ImVec2* points, int pointCount, uint32_t color, float thickness)
{
	for (int i = 0; i < pointCount - 1; i++)
	{
		RenderLine(points[i], points[i + 1], color, thickness);
	}
	RenderLine(points[pointCount - 1], points[0], color, thickness);
}

void Renderer::RenderCircle(const ImVec2& position, float radius, uint32_t color, float thickness, uint32_t segments)
{
	ImGuiWindow* window = ImGui::GetCurrentWindow();

	float a = (color >> 24) & 0xff;
	float r = (color >> 16) & 0xff;
	float g = (color >> 8) & 0xff;
	float b = (color) & 0xff;

	window->DrawList->AddCircle(position, radius, ImGui::GetColorU32({ r / 255.0f, g / 255.0f, b / 255.0f, a / 255.0f }), segments, thickness);
}

void Renderer::RenderCircleFilled(const ImVec2& position, float radius, uint32_t color, uint32_t segments)
{
	ImGuiWindow* window = ImGui::GetCurrentWindow();

	float a = (color >> 24) & 0xff;
	float r = (color >> 16) & 0xff;
	float g = (color >> 8) & 0xff;
	float b = (color) & 0xff;

	window->DrawList->AddCircleFilled(position, radius, ImGui::GetColorU32({ r / 255.0f, g / 255.0f, b / 255.0f, a / 255.0f }), segments);
}

void Renderer::RenderRect(const ImVec2& from, const ImVec2& to, uint32_t color, float rounding, uint32_t roundingCornersFlags, float thickness)
{
	ImGuiWindow* window = ImGui::GetCurrentWindow();

	float a = (color >> 24) & 0xFF;
	float r = (color >> 16) & 0xFF;
	float g = (color >> 8) & 0xFF;
	float b = (color) & 0xFF;

	window->DrawList->AddRect(from, to, ImGui::GetColorU32({ r / 255.0f, g / 255.0f, b / 255.0f, a / 255.0f }), rounding, roundingCornersFlags, thickness);
}

void Renderer::RenderRect(const ImVec2& one, const ImVec2& two, const ImVec2& three, const ImVec2& four, uint32_t color, float thickness)
{
	ImGuiWindow* window = ImGui::GetCurrentWindow();

	float a = (color >> 24) & 0xFF;
	float r = (color >> 16) & 0xFF;
	float g = (color >> 8) & 0xFF;
	float b = (color) & 0xFF;

	window->DrawList->AddLine(one, two, ImGui::GetColorU32({ r / 255.0f, g / 255.0f, b / 255.0f, a / 255.0f }), thickness);
	window->DrawList->AddLine(two, three, ImGui::GetColorU32({ r / 255.0f, g / 255.0f, b / 255.0f, a / 255.0f }), thickness);
	window->DrawList->AddLine(three, four, ImGui::GetColorU32({ r / 255.0f, g / 255.0f, b / 255.0f, a / 255.0f }), thickness);
	window->DrawList->AddLine(four, one, ImGui::GetColorU32({ r / 255.0f, g / 255.0f, b / 255.0f, a / 255.0f }), thickness);
}

void Renderer::RenderRectFilled(const ImVec2& from, const ImVec2& to, uint32_t color, float rounding, uint32_t roundingCornersFlags)
{
	ImGuiWindow* window = ImGui::GetCurrentWindow();

	float a = (color >> 24) & 0xFF;
	float r = (color >> 16) & 0xFF;
	float g = (color >> 8) & 0xFF;
	float b = (color) & 0xFF;

	window->DrawList->AddRectFilled(from, to, ImGui::GetColorU32({ r / 255.0f, g / 255.0f, b / 255.0f, a / 255.0f }), rounding, roundingCornersFlags);
}

void Renderer::DrawUnitCollisionRectangle(ImVec2 screenPositionCenter, ImVec2 collision, uint32_t color)
{
	ImVec2 ivOne = ImVec2(screenPositionCenter.x - collision.x, screenPositionCenter.y - collision.y);
	ImVec2 ivTwo = ImVec2(screenPositionCenter.x + collision.x, screenPositionCenter.y - collision.y);
	ImVec2 ivThree = ImVec2(screenPositionCenter.x + collision.x, screenPositionCenter.y + collision.y);
	ImVec2 ivFour = ImVec2(screenPositionCenter.x + collision.x, screenPositionCenter.y - collision.y);

	Renderer::Get()->RenderRect(ivOne, ivTwo, ivThree, ivFour, color);
}