/*
 * Copyright 2014 Kai Jourdan. All rights reserved.
 * License: https://github.com/bkaradzic/bgfx#license-bsd-2-clause
 *
 */

#include "common.h"
#include "bgfx_utils.h"

#include "vectordisplay.h"
#include "imgui/imgui.h"

namespace
{

struct PosColorVertex
{
	float m_x;
	float m_y;
	float m_z;
	uint32_t m_abgr;

	static void init()
	{
		ms_layout
			.begin()
			.add(bgfx::Attrib::Position, 3, bgfx::AttribType::Float)
			.add(bgfx::Attrib::Color0, 4, bgfx::AttribType::Uint8, true)
			.end();
	}

	static bgfx::VertexLayout ms_layout;
};

bgfx::VertexLayout PosColorVertex::ms_layout;

class ExampleVectorDisplay : public entry::AppI
{
public:
	ExampleVectorDisplay(const char* _name, const char* _description, const char* _url)
		: entry::AppI(_name, _description, _url)
	{
	}

	void init(int32_t _argc, const char* const* _argv, uint32_t _width, uint32_t _height) override
	{
		Args args(_argc, _argv);
		m_width  = _width;
		m_height = _height;
		m_debug = BGFX_DEBUG_NONE;
		m_reset = BGFX_RESET_VSYNC;

		bgfx::Init init;
		init.type     = args.m_type;
		init.vendorId = args.m_pciId;
		init.resolution.width  = m_width;
		init.resolution.height = m_height;
		init.resolution.reset  = m_reset;
		bgfx::init(init);

		const bgfx::RendererType::Enum renderer = bgfx::getRendererType();
		float texelHalf = bgfx::RendererType::Direct3D9 == renderer ? 0.5f : 0.0f;
		bool originBottomLeft = bgfx::RendererType::OpenGL == renderer
		|| bgfx::RendererType::OpenGLES == renderer;
		m_vd.init(originBottomLeft, texelHalf);
		m_vd.setup(uint16_t(m_width), uint16_t(m_height) );

		// Enable debug text.
		bgfx::setDebug(m_debug);

		// Set view 0 clear state.
		bgfx::setViewClear(0, BGFX_CLEAR_COLOR | BGFX_CLEAR_DEPTH, 0x303030ff, 1.0f, 0);

		// Create vertex stream declaration.
		PosColorVertex::init();

		m_oldWidth = m_width;
		m_oldHeight = m_height;

		imguiCreate();
	}

	virtual int shutdown() override
	{
		imguiDestroy();

		// Cleanup.
		m_vd.teardown();

		// Shutdown bgfx.
		bgfx::shutdown();

		return 0;
	}

	bool update() override
	{
		if (!entry::processEvents(m_width, m_height, m_debug, m_reset, &m_mouseState) )
		{
			imguiBeginFrame(m_mouseState.m_mx
				,  m_mouseState.m_my
				, (m_mouseState.m_buttons[entry::MouseButton::Left  ] ? IMGUI_MBUT_LEFT   : 0)
				| (m_mouseState.m_buttons[entry::MouseButton::Right ] ? IMGUI_MBUT_RIGHT  : 0)
				| (m_mouseState.m_buttons[entry::MouseButton::Middle] ? IMGUI_MBUT_MIDDLE : 0)
				,  m_mouseState.m_mz
				, uint16_t(m_width)
				, uint16_t(m_height)
				);

			showExampleDialog(this);

			imguiEndFrame();

			if (m_oldWidth  != m_width
			||  m_oldHeight != m_height)
			{
				m_oldWidth  = m_width;
				m_oldHeight = m_height;
				m_vd.resize(uint16_t(m_width), uint16_t(m_height) );
			}

			const bx::Vec3 at  = { 0.0f, 0.0f,   0.0f };
			const bx::Vec3 eye = { 0.0f, 0.0f, -35.0f };

			float view[16];
			float proj[16];
			bx::mtxLookAt(view, eye, at);
			bx::mtxProj(proj, 60.0f, float(m_width) / float(m_height), 0.1f, 100.0f, bgfx::getCaps()->homogeneousDepth);
			// Set view and projection matrix for view 0.
			bgfx::setViewTransform(0, view, proj);

			// Set view 0 default viewport.
			bgfx::setViewRect(0, 0, 0, uint16_t(m_width), uint16_t(m_height) );

			// This dummy draw call is here to make sure that view 0 is cleared
			// if no other draw calls are submitted to view 0.
			bgfx::touch(0);

			m_vd.beginFrame();

			//simplex test
			m_vd.setDrawColor(0.7f, 0.7f, 1.0f);
			m_vd.drawSimplexFont(50.0f,  80.0f, 1.5f, "ABCDEFGHIJKLMNOPQRSTUVWXYZ");
			m_vd.drawSimplexFont(50.0f, 140.0f, 1.5f, "abcdefghijklmnopqrstuvwxyz");
			m_vd.drawSimplexFont(50.0f, 200.0f, 1.5f, "!@#$%^&*()-=<>/?;:'\"{}[]|\\+=-_");

			m_vd.setDrawColor(1.0f, 0.7f, 0.7f);

			//test pattern for lines
			for (int ii = 0; ii < 4; ii++)
			{
				for (int jj = 0; jj < ii; jj++) //draw more intensive lines
				{
					m_vd.drawLine(50.0f, 350.0f + 40 * ii, 200.0f, 350.0f + 40 * ii);
				}
			}

			for (int ii = 0; ii < 4; ii++)
			{
				for (int jj = 0; jj <= ii; jj++)
				{
					m_vd.drawLine(50.0f + 40 * ii, 600.0f, 50.0f + 40 * ii, 700.0f);
				}
			}

			//
			// test pattern for shapes
			//
			m_vd.setDrawColor(0.7f, 0.7f, 1.0f);
			m_vd.drawCircle(250.0f, 450.0f, 10.0f, 32.0f);
			m_vd.drawCircle(300.0f, 450.0f, 30.0f, 32.0f);
			m_vd.drawCircle(400.0f, 450.0f, 60.0f, 32.0f);
			m_vd.drawCircle(500.0f, 450.0f, 80.0f, 64.0f);

			m_vd.setDrawColor(0.7f, 1.0f, 0.7f);
			m_vd.drawBox(250.0f, 600.0f, 10.0f, 10.0f);
			m_vd.drawBox(300.0f, 600.0f, 30.0f, 30.0f);
			m_vd.drawBox(350.0f, 600.0f, 60.0f, 60.0f);
			m_vd.drawBox(450.0f, 600.0f, 80.0f, 80.0f);

			m_vd.setDrawColor(1.0f, 0.7f, 1.0f);
			m_vd.drawWheel(bx::kPi, 800.0f, 450.0f, 80.0f);
			m_vd.drawWheel(3.0f * bx::kPi / 4.0f, 95.0f, 450.0f, 60.0f);
			m_vd.drawWheel(bx::kPi / 2.0f, 1150.0f, 450.0f, 30.0f);
			m_vd.drawWheel(bx::kPi / 4.0f, 1250.0f, 450.0f, 10.0f);

			// draw moving shape
			static float counter = 0.0f;
			counter += 0.01f;

			const float posX = m_width  / 2.0f + bx::sin(counter * 3.18378f) * (m_width / 2.0f);
			const float posY = m_height / 2.0f + bx::cos(counter) * (m_height / 2.0f);
			m_vd.drawCircle(posX, posY, 5.0f, 10.0f);

			m_vd.endFrame();

			// Advance to next frame. Rendering thread will be kicked to
			// process submitted rendering primitives.
			bgfx::frame();

			return true;
		}

		return false;
	}

	entry::MouseState m_mouseState;

	uint32_t m_width;
	uint32_t m_height;
	uint32_t m_debug;
	uint32_t m_reset;
	VectorDisplay m_vd;

	uint32_t m_oldWidth;
	uint32_t m_oldHeight;
};

} // namespace

ENTRY_IMPLEMENT_MAIN(
	  ExampleVectorDisplay
	, "23-vectordisplay"
	, "Rendering lines as oldschool vectors."
	, "https://bkaradzic.github.io/bgfx/examples.html#vectordisplay"
	);