// MIT License

// Copyright (c) 2019 Erin Catto

// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:

// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.

// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.

#include "test.h"
#include "imgui/imgui.h"

class EdgeTest : public Test
{
public:

	EdgeTest()
	{
		b2Vec2 vertices[10] =
		{
			{10.0f, -4.0f},
			{10.0f, 0.0f},
			{6.0f, 0.0f},
			{4.0f, 2.0f},
			{2.0f, 0.0f},
			{-2.0f, 0.0f},
			{-6.0f, 0.0f},
			{-8.0f, -3.0f},
			{-10.0f, 0.0f},
			{-10.0f, -4.0f}
		};

		m_offset1.Set(0.0f, 8.0f);
		m_offset2.Set(0.0f, 16.0f);

		{
			b2Vec2 v1 = vertices[0] + m_offset1;
			b2Vec2 v2 = vertices[1] + m_offset1;
			b2Vec2 v3 = vertices[2] + m_offset1;
			b2Vec2 v4 = vertices[3] + m_offset1;
			b2Vec2 v5 = vertices[4] + m_offset1;
			b2Vec2 v6 = vertices[5] + m_offset1;
			b2Vec2 v7 = vertices[6] + m_offset1;
			b2Vec2 v8 = vertices[7] + m_offset1;
			b2Vec2 v9 = vertices[8] + m_offset1;
			b2Vec2 v10 = vertices[9] + m_offset1;

			b2BodyDef bd;
			b2Body* ground = m_world->CreateBody(&bd);

			b2EdgeShape shape;

			shape.SetOneSided(v10, v1, v2, v3);
			ground->CreateFixture(&shape, 0.0f);

			shape.SetOneSided(v1, v2, v3, v4);
			ground->CreateFixture(&shape, 0.0f);

			shape.SetOneSided(v2, v3, v4, v5);
			ground->CreateFixture(&shape, 0.0f);

			shape.SetOneSided(v3, v4, v5, v6);
			ground->CreateFixture(&shape, 0.0f);

			shape.SetOneSided(v4, v5, v6, v7);
			ground->CreateFixture(&shape, 0.0f);

			shape.SetOneSided(v5, v6, v7, v8);
			ground->CreateFixture(&shape, 0.0f);

			shape.SetOneSided(v6, v7, v8, v9);
			ground->CreateFixture(&shape, 0.0f);

			shape.SetOneSided(v7, v8, v9, v10);
			ground->CreateFixture(&shape, 0.0f);

			shape.SetOneSided(v8, v9, v10, v1);
			ground->CreateFixture(&shape, 0.0f);

			shape.SetOneSided(v9, v10, v1, v2);
			ground->CreateFixture(&shape, 0.0f);
		}

		{
			b2Vec2 v1 = vertices[0] + m_offset2;
			b2Vec2 v2 = vertices[1] + m_offset2;
			b2Vec2 v3 = vertices[2] + m_offset2;
			b2Vec2 v4 = vertices[3] + m_offset2;
			b2Vec2 v5 = vertices[4] + m_offset2;
			b2Vec2 v6 = vertices[5] + m_offset2;
			b2Vec2 v7 = vertices[6] + m_offset2;
			b2Vec2 v8 = vertices[7] + m_offset2;
			b2Vec2 v9 = vertices[8] + m_offset2;
			b2Vec2 v10 = vertices[9] + m_offset2;

			b2BodyDef bd;
			b2Body* ground = m_world->CreateBody(&bd);

			b2EdgeShape shape;

			shape.SetTwoSided(v1, v2);
			ground->CreateFixture(&shape, 0.0f);

			shape.SetTwoSided(v2, v3);
			ground->CreateFixture(&shape, 0.0f);

			shape.SetTwoSided(v3, v4);
			ground->CreateFixture(&shape, 0.0f);

			shape.SetTwoSided(v4, v5);
			ground->CreateFixture(&shape, 0.0f);

			shape.SetTwoSided(v5, v6);
			ground->CreateFixture(&shape, 0.0f);

			shape.SetTwoSided(v6, v7);
			ground->CreateFixture(&shape, 0.0f);

			shape.SetTwoSided(v7, v8);
			ground->CreateFixture(&shape, 0.0f);

			shape.SetTwoSided(v8, v9);
			ground->CreateFixture(&shape, 0.0f);

			shape.SetTwoSided(v9, v10);
			ground->CreateFixture(&shape, 0.0f);

			shape.SetTwoSided(v10, v1);
			ground->CreateFixture(&shape, 0.0f);
		}

		m_body1 = nullptr;
		m_body2 = nullptr;
		CreateBoxes();
		m_boxes = true;
	}

	void CreateBoxes()
	{
		if (m_body1)
		{
			m_world->DestroyBody(m_body1);
			m_body1 = nullptr;
		}

		if (m_body2)
		{
			m_world->DestroyBody(m_body2);
			m_body2 = nullptr;
		}

		{
			b2BodyDef bd;
			bd.type = b2_dynamicBody;
			bd.position = b2Vec2(8.0f, 2.6f) + m_offset1;
			bd.allowSleep = false;
			m_body1 = m_world->CreateBody(&bd);

			b2PolygonShape shape;
			shape.SetAsBox(0.5f, 1.0f);

			m_body1->CreateFixture(&shape, 1.0f);
		}

		{
			b2BodyDef bd;
			bd.type = b2_dynamicBody;
			bd.position = b2Vec2(8.0f, 2.6f) + m_offset2;
			bd.allowSleep = false;
			m_body2 = m_world->CreateBody(&bd);

			b2PolygonShape shape;
			shape.SetAsBox(0.5f, 1.0f);

			m_body2->CreateFixture(&shape, 1.0f);
		}
	}

	void CreateCircles()
	{
		if (m_body1)
		{
			m_world->DestroyBody(m_body1);
			m_body1 = nullptr;
		}

		if (m_body2)
		{
			m_world->DestroyBody(m_body2);
			m_body2 = nullptr;
		}

		{
			b2BodyDef bd;
			bd.type = b2_dynamicBody;
			bd.position = b2Vec2(-0.5f, 0.6f) + m_offset1;
			bd.allowSleep = false;
			m_body1 = m_world->CreateBody(&bd);

			b2CircleShape shape;
			shape.m_radius = 0.5f;

			m_body1->CreateFixture(&shape, 1.0f);
		}

		{
			b2BodyDef bd;
			bd.type = b2_dynamicBody;
			bd.position = b2Vec2(-0.5f, 0.6f) + m_offset2;
			bd.allowSleep = false;
			m_body2 = m_world->CreateBody(&bd);

			b2CircleShape shape;
			shape.m_radius = 0.5f;

			m_body2->CreateFixture(&shape, 1.0f);
		}
	}

	void UpdateUI() override
	{
		ImGui::SetNextWindowPos(ImVec2(10.0f, 100.0f));
		ImGui::SetNextWindowSize(ImVec2(200.0f, 100.0f));
		ImGui::Begin("Custom Controls", nullptr, ImGuiWindowFlags_NoMove | ImGuiWindowFlags_NoResize);

		if (ImGui::RadioButton("Boxes", m_boxes == true))
		{
			CreateBoxes();
			m_boxes = true;
		}

		if (ImGui::RadioButton("Circles", m_boxes == false))
		{
			CreateCircles();
			m_boxes = false;
		}

		ImGui::End();
	}

	void Step(Settings& settings) override
	{
		if (glfwGetKey(g_mainWindow, GLFW_KEY_A) == GLFW_PRESS)
		{
			m_body1->ApplyForceToCenter(b2Vec2(-10.0f, 0.0f), true);
			m_body2->ApplyForceToCenter(b2Vec2(-10.0f, 0.0f), true);
		}

		if (glfwGetKey(g_mainWindow, GLFW_KEY_D) == GLFW_PRESS)
		{
			m_body1->ApplyForceToCenter(b2Vec2(10.0f, 0.0f), true);
			m_body2->ApplyForceToCenter(b2Vec2(10.0f, 0.0f), true);
		}

		Test::Step(settings);
	}

	static Test* Create()
	{
		return new EdgeTest;
	}

	b2Vec2 m_offset1, m_offset2;
	b2Body* m_body1;
	b2Body* m_body2;
	bool m_boxes;
};

static int testIndex = RegisterTest("Geometry", "Edge Test", EdgeTest::Create);