#include <iostream>
#include <Ogre.h>
#include <OgreMeshLodGenerator.h>
#include <OgreCompositorManager.h>
#include <OgreMaterialManager.h>
#include "water.h"

static const uint32_t SUBMERGED_MASK = 0x0F0;
static const uint32_t SURFACE_MASK = 0x00F;
static const uint32_t WATER_MASK = 0xF00;
Water::Water()
	: RenderTargetListener()
	, mWaterNode(nullptr)
	, mScnMgr(nullptr)
	, mWindow(nullptr)
	, mCameraNode(nullptr)
	, mWaterPlane(Ogre::Vector3::UNIT_Y, 0)
	, mReflectionPlane(Ogre::Vector3(0.0, 1.0, 0.0), 0.0f /* water height */)
	, mReflectionClipPlaneAbove(Ogre::Vector3(0.0, 1.0, 0.0), 0.0f /* water height */ - 2.0f)
	, mReflectionClipPlaneBelow(Ogre::Vector3(0.0, -1.0, 0.0), -(0.0f /* water height */ + 2.0))
	, mRefractionClipPlaneAbove(Ogre::Vector3(0.0, -1.0, 0.0), -(0.0f /* water height */ + 2.0))
	, mRefractionClipPlaneBelow(Ogre::Vector3(0.0, 1.0, 0.0), 0.0f /* water height */ - 2.0)
	, mAbove(true)
{
}

Water::~Water()
{
	if (mWaterNode)
		mScnMgr->destroySceneNode(mWaterNode);
	if(mReflectionTexture)
		mReflectionTexture->removeAllListeners();
#if 0
	if(mRefractionTexture)
		mRefractionTexture->removeAllListeners();
#endif
}

void Water::create_cameras()
{
	mReflectionTexture->addListener(this);
	mReflectionCamera = mScnMgr->createCamera("ReflectionCamera");
	mCamera->getParentSceneNode()->attachObject(mReflectionCamera);
	mReflectionCamera->setAspectRatio(mCamera->getAspectRatio());
	mReflectionCamera->setNearClipDistance(mCamera->getNearClipDistance());
	mReflectionCamera->setFarClipDistance(mCamera->getFarClipDistance());
	mReflectionCamera->enableCustomNearClipPlane(mReflectionClipPlaneAbove);
	mReflectionCamera->enableReflection(mReflectionPlane);

	Ogre::Viewport * reflectionViewport = mReflectionTexture->addViewport(mReflectionCamera, 0, 0, 0, 0.5f, 1.0f);
	reflectionViewport->setClearEveryFrame(true);
	reflectionViewport->setBackgroundColour(Ogre::ColourValue(0.0, 0.0, 1.0, 1.0));
	reflectionViewport->setOverlaysEnabled(false);
	reflectionViewport->setSkiesEnabled(true);
	reflectionViewport->setAutoUpdated(false);
	mViewports.push_back(reflectionViewport);

	// mRefractionTexture->addListener(this);
#if 1
	mRefractionCamera = mScnMgr->createCamera("RefractionCamera");
	mCamera->getParentSceneNode()->attachObject(mRefractionCamera);
	mRefractionCamera->setAspectRatio(mCamera->getAspectRatio());
	mRefractionCamera->setNearClipDistance(mCamera->getNearClipDistance());
	mRefractionCamera->setFarClipDistance(mCamera->getFarClipDistance());
	mRefractionCamera->enableCustomNearClipPlane(mRefractionClipPlaneAbove);

	Ogre::Viewport * refractionViewport = mReflectionTexture->addViewport(mRefractionCamera, 1, 0.5, 0, 0.5f, 1.0f);
	refractionViewport->setClearEveryFrame(true);
	refractionViewport->setBackgroundColour(Ogre::ColourValue(0.0, 0.5, 1.0, 1.0));
	refractionViewport->setOverlaysEnabled(false);
	refractionViewport->setSkiesEnabled(false);
	refractionViewport->setAutoUpdated(false);
	mViewports.push_back(refractionViewport);
#endif
}

void Water::create_textures()
{
	Ogre::TexturePtr reflectionTexture = Ogre::TextureManager::getSingleton().createManual(
		"ReflectionRefractionTexture",
		Ogre::ResourceGroupManager::DEFAULT_RESOURCE_GROUP_NAME,
		Ogre::TEX_TYPE_2D, 512, 512,
		0,
		Ogre::PF_R8G8B8A8,
		Ogre::TU_RENDERTARGET);

	mReflectionTexture = reflectionTexture->getBuffer()->getRenderTarget();
	mReflectionTexture->setAutoUpdated(false);
#if 0
	Ogre::TexturePtr refractionTexture = Ogre::TextureManager::getSingleton().createManual(
		"RefractionTexture",
		Ogre::ResourceGroupManager::DEFAULT_RESOURCE_GROUP_NAME,
		Ogre::TEX_TYPE_2D, 512, 512,
		0,
		Ogre::PF_R8G8B8A8,
		Ogre::TU_RENDERTARGET);

	mRefractionTexture = refractionTexture->getBuffer()->getRenderTarget();
#endif
}

void Water::init()
{
	int i;
	float w = 1000.0f;
	// mWindow->addListener(this);
	create_cameras();
	Ogre::MeshPtr water_plane =
		Ogre::MeshManager::getSingleton().createPlane(
			"water",
			Ogre::ResourceGroupManager::DEFAULT_RESOURCE_GROUP_NAME,
			mWaterPlane, w, w, 100, 100, true, 1, 100, 100,
			Ogre::Vector3::UNIT_Z);
	if (!Ogre::MeshLodGenerator::getSingletonPtr())
		new Ogre::MeshLodGenerator();

	Ogre::LodConfig lod_config(water_plane);
	lod_config.createGeneratedLodLevel(w, 0.5f);
	lod_config.createGeneratedLodLevel(w * 2.0, 0.25f);
	Ogre::MeshLodGenerator::getSingleton().generateLodLevels(lod_config);

	Ogre::Vector3 positions[] = { { 0, 0, 0 },  { 0, 0, -1 }, { 0, 0, 1 },
				      { -1, 0, 0 }, { 1, 0, 0 },  { -1, 0, -1 },
				      { -1, 0, 1 }, { 1, 0, -1 }, { 1, 0, 1 } };
	mWaterNode = mScnMgr->getRootSceneNode()->createChildSceneNode("Water");

	auto mat = Ogre::MaterialManager::getSingleton().getByName("Water/Above");
	mat->load();
	mat->setReceiveShadows(false);
#if 0
	mat->getTechnique(0)
		->getPass(0)
		->getTextureUnitState(0)
		->setProjectiveTexturing(true, mCamera);
#endif
	auto mat2 = Ogre::MaterialManager::getSingleton().getByName("Water/Below");
	mat2->load();
	mat2->setReceiveShadows(false);
#if 0
	mat2->getTechnique(0)
		->getPass(0)
		->getTextureUnitState(0)
		->setProjectiveTexturing(true, mCamera);
#endif

	for (i = 0; i < (int)sizeof(positions) / (int)sizeof(positions[0]);
	     i++) {
		Ogre::Entity *water_lod1 = mScnMgr->createEntity(
			"Water" + Ogre::StringConverter::toString(i), "water");
		water_lod1->setVisibilityFlags(WATER_MASK);
		water_lod1->setCastShadows(true);
		water_lod1->setMaterialName("Water/Above");
		water_lod1->setMaterial(mat);
		Ogre::SceneNode *node_w = mWaterNode->createChildSceneNode(
			"Water" + Ogre::StringConverter::toString(i),
			positions[i] * w, Ogre::Quaternion::IDENTITY);
		node_w->attachObject(water_lod1);
		water_lod1->setVisibilityFlags(WATER_MASK);
		mWaterMeshes.push_back(water_lod1);
	}
	/*
	Ogre::Root::getSingleton().addFrameListener(this);
	*/
}

void Water::createWater(Ogre::RenderWindow * window, Ogre::Camera *camera)
{
	int i;
	mCamera = camera;
	mScnMgr = camera->getSceneManager();
	mCameraNode = camera->getParentSceneNode();
	Ogre::Viewport *viewport = camera->getViewport();
	mWindow = window;
	mCameraPosition = mCameraNode->getPosition();
	create_textures();
}

void Water::updateWater(float delta)
{
	int i;
	if (mCameraPosition.squaredDistance(mCameraNode->getPosition()) >
	    200.0f * 200.0f) {
		mCameraPosition = mCameraNode->getPosition();
		Ogre::Vector3 waterPosition = mCameraPosition;
		waterPosition.y = 0;
		mWaterNode->setPosition(waterPosition);
	}
	if (mAbove) {
		if (mCameraNode->getPosition().y < 0) {
			mAbove = false;
			for (i = 0; i < mWaterMeshes.size(); i++)
				mWaterMeshes[i]->setMaterialName("Water/Below");
		}
	} else {
		if (mCameraNode->getPosition().y > 0) {
			mAbove = true;
			for (i = 0; i < mWaterMeshes.size(); i++)
				mWaterMeshes[i]->setMaterialName("Water/Above");
		}
	}
	for (i = 0; i < mWaterMeshes.size(); i++)
		mWaterMeshes[i]->setVisible(false);
	for (i = 0; i < mViewports.size(); i++)
		mViewports[i]->update();
//	mReflectionTexture->update();
	for (i = 0; i < mWaterMeshes.size(); i++)
		mWaterMeshes[i]->setVisible(true);
}

/*
bool Water::frameEnded(const Ogre::FrameEvent &evt)
{
	updateWater(evt.timeSinceLastFrame);
	return true;
}
bool Water::frameRenderingQueued(const Ogre::FrameEvent &evt)
{
	return FrameListener::frameRenderingQueued(evt);
}
*/

void Water::preRenderTargetUpdate(const Ogre::RenderTargetEvent &evt)
{
	int i;
	if (evt.source == mReflectionTexture /*|| evt.source == mRefractionTexture */) {
		for (i = 0; i < mWaterMeshes.size(); i++)
			mWaterMeshes[i]->setVisible(false);
		if (evt.source == mReflectionTexture)
			mInRefTexUpdate = true;
	} else {
		for (i = 0; i < mWaterMeshes.size(); i++)
			mWaterMeshes[i]->setVisible(true);
		mInRefTexUpdate = false;
	}
}

void Water::postRenderTargetUpdate(const Ogre::RenderTargetEvent &evt)
{
	int i;
	for (i = 0; i < mWaterMeshes.size(); i++)
		mWaterMeshes[i]->setVisible(true);
	mInRefTexUpdate = false;
}

void Water::add_submerged_entity(Ogre::Entity *ent)
{
	ent->setVisibilityFlags(SUBMERGED_MASK);
}

void Water::add_surface_entity(Ogre::Entity *ent)
{
	ent->setVisibilityFlags(SURFACE_MASK);
}
void Water::dump_textures()
{
	mReflectionTexture->writeContentsToFile("Reflection.png");
	// mRefractionTexture->writeContentsToFile("Refraction.png");
}