/***************************************************************************
 *   Copyright (C) 2005-2008 by the FIFE team                              *
 *   http://www.fifengine.de                                               *
 *   This file is part of FIFE.                                            *
 *                                                                         *
 *   FIFE is free software; you can redistribute it and/or                 *
 *   modify it under the terms of the GNU Lesser General Public            *
 *   License as published by the Free Software Foundation; either          *
 *   version 2.1 of the License, or (at your option) any later version.    *
 *                                                                         *
 *   This library is distributed in the hope that it will be useful,       *
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU     *
 *   Lesser General Public License for more details.                       *
 *                                                                         *
 *   You should have received a copy of the GNU Lesser General Public      *
 *   License along with this library; if not, write to the                 *
 *   Free Software Foundation, Inc.,                                       *
 *   51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA          *
 ***************************************************************************/

// Standard C++ library includes

// 3rd party library includes

// FIFE includes
// These includes are split up in two parts, separated by one empty line
// First block: files included from the FIFE root src directory
// Second block: files included from the same folder
#include "video/renderbackend.h"
#include "video/image.h"
#include "video/sdl/sdlimage.h"
#include "video/imagepool.h"
#include "video/animation.h"
#include "video/animationpool.h"
#include "util/math/fife_math.h"
#include "util/log/logger.h"
#include "model/metamodel/grids/cellgrid.h"
#include "model/metamodel/action.h"
#include "model/structures/instance.h"
#include "model/structures/layer.h"
#include "model/structures/location.h"

#include "view/camera.h"
#include "view/visual.h"
#include "instancerenderer.h"

namespace {
	unsigned int scale(unsigned int val, double factor) {
		return static_cast<unsigned int>(ceil(static_cast<double>(val) * factor));
	}
}

namespace FIFE {
	static Logger _log(LM_VIEWVIEW);

	InstanceRenderer::OutlineInfo::OutlineInfo():
		r(0),
		g(0),
		b(0),
		width(1),
		dirty(false),
		outline(NULL),
		curimg(NULL) {
	}
	InstanceRenderer::ColoringInfo::ColoringInfo():
		r(0),
		g(0),
		b(0),
		dirty(false),
		overlay(NULL),
		curimg(NULL) {
	}

	InstanceRenderer::OutlineInfo::~OutlineInfo() {
		delete outline;
	}

	InstanceRenderer::ColoringInfo::~ColoringInfo() {
		delete overlay;
	}

	InstanceRenderer* InstanceRenderer::getInstance(IRendererContainer* cnt) {
		return dynamic_cast<InstanceRenderer*>(cnt->getRenderer("InstanceRenderer"));
	}

	InstanceRenderer::InstanceRenderer(RenderBackend* renderbackend, int position, ImagePool* imagepool, AnimationPool* animpool):
		RendererBase(renderbackend, position),
		m_imagepool(imagepool),
		m_animationpool(animpool) {
		setEnabled(true);
	}

 	InstanceRenderer::InstanceRenderer(const InstanceRenderer& old):
		RendererBase(old),
		m_imagepool(old.m_imagepool),
		m_animationpool(old.m_animationpool) {
		setEnabled(true);
	}

	RendererBase* InstanceRenderer::clone() {
		return new InstanceRenderer(*this);
	}

	InstanceRenderer::~InstanceRenderer() {
	}

	void InstanceRenderer::render(Camera* cam, Layer* layer, RenderList& instances) {
		// patch #335 by abeyer
		if (!layer->areInstancesVisible()) {
			FL_DBG(_log, "Layer instances hidden");
			return;
		}

		FL_DBG(_log, "Iterating layer...");
		CellGrid* cg = layer->getCellGrid();
		if (!cg) {
			FL_WARN(_log, "No cellgrid assigned to layer, cannot draw instances");
			return;
		}

		const bool any_effects = !(m_instance_outlines.empty() && m_instance_colorings.empty());

		RenderList::iterator instance_it = instances.begin(); 
		for (;instance_it != instances.end(); ++instance_it) {
			FL_DBG(_log, "Iterating instances...");
			Instance* instance = (*instance_it)->instance;
			InstanceVisual* visual = instance->getVisual<InstanceVisual>();
			RenderItem& vc = **instance_it;
			unsigned char trans = visual->getTransparency();

			/**
			 *  the instance transparency value take precedence. If it's 0 use the layer trans
			 *
			 *	\todo Instances cannot be completely opaque when their layer's transparency is non zero.
			 */
			if (trans == 0) {
				unsigned char layer_trans = layer->getLayerTransparency();
				trans = layer_trans;
			}

			FL_DBG(_log, LMsg("Instance layer coordinates = ") << instance->getLocationRef().getLayerCoordinates());

			if (any_effects) {
				InstanceToOutlines_t::iterator outline_it = m_instance_outlines.find(instance);
				if (outline_it != m_instance_outlines.end()) {
					bindOutline(outline_it->second, vc, cam)->render(vc.dimensions, 255-trans);
				}

				InstanceToColoring_t::iterator coloring_it = m_instance_colorings.find(instance);
				if (coloring_it != m_instance_colorings.end()) {
					bindColoring(coloring_it->second, vc, cam)->render(vc.dimensions, 255-trans);
					continue; // Skip normal rendering after drawing overlay
				}
			}

			vc.image->render(vc.dimensions, 255-trans);
		}
	}

	Image* InstanceRenderer::bindOutline(OutlineInfo& info, RenderItem& vc, Camera* cam) {
		if (!info.dirty && info.curimg == vc.image) {
			// optimization for outline that has not changed
			return info.outline;
		} else {
			info.curimg = vc.image;
		}

		if (info.outline) {
			delete info.outline; // delete old mask
			info.outline = NULL;
		}
		SDL_Surface* surface = vc.image->getSurface();
		SDL_Surface* outline_surface = SDL_ConvertSurface(surface, surface->format, surface->flags);

		// needs to use SDLImage here, since GlImage does not support drawing primitives atm
		SDLImage* img = new SDLImage(outline_surface);

		// TODO: optimize...
		uint8_t r, g, b, a = 0;

		// vertical sweep
		for (unsigned int x = 0; x < img->getWidth(); x ++) {
			uint8_t prev_a = 0;
			for (unsigned int y = 0; y < img->getHeight(); y ++) {
				vc.image->getPixelRGBA(x, y, &r, &g, &b, &a);
				if ((a == 0 || prev_a == 0) && (a != prev_a)) {
					if (a < prev_a) {
						for (unsigned int yy = y; yy < y + info.width; yy++) {
							img->putPixel(x, yy, info.r, info.g, info.b);
						}
					} else {
						for (unsigned int yy = y - info.width; yy < y; yy++) {
							img->putPixel(x, yy, info.r, info.g, info.b);
						}
					}
				}
				prev_a = a;
			}
		}
		// horizontal sweep
		for (unsigned int y = 0; y < img->getHeight(); y ++) {
			uint8_t prev_a = 0;
			for (unsigned int x = 0; x < img->getWidth(); x ++) {
				vc.image->getPixelRGBA(x, y, &r, &g, &b, &a);
				if ((a == 0 || prev_a == 0) && (a != prev_a)) {
					if (a < prev_a) {
						for (unsigned int xx = x; xx < x + info.width; xx++) {
							img->putPixel(xx, y, info.r, info.g, info.b);
						}
					} else {
						for (unsigned int xx = x - info.width; xx < x; xx++) {
							img->putPixel(xx, y, info.r, info.g, info.b);
						}
					}
				}
				prev_a = a;
			}
		}

		// In case of OpenGL backend, SDLImage needs to be converted
		info.outline = m_renderbackend->createImage(img->detachSurface());
		delete img;

		if (info.outline) {
			// mark outline as not dirty since we created it here
			info.dirty = false;
		}

		return info.outline;
	}

	Image* InstanceRenderer::bindColoring(ColoringInfo& info, RenderItem& vc, Camera* cam) {
		if (!info.dirty && info.curimg == vc.image) {
			// optimization for coloring overlay that has not changed
			return info.overlay;
		}
		else {
			info.curimg = vc.image;
		}
		
		if (info.overlay) {
			delete info.overlay; // delete old mask
			info.overlay = NULL;
		}

		SDL_Surface* surface = vc.image->getSurface();
		SDL_Surface* overlay_surface = SDL_ConvertSurface(surface, surface->format, surface->flags);

		// needs to use SDLImage here, since GlImage does not support drawing primitives atm
		SDLImage* img = new SDLImage(overlay_surface);

		uint8_t r, g, b, a = 0;

		for (unsigned int x = 0; x < img->getWidth(); x ++) {
			for (unsigned int y = 0; y < img->getHeight(); y ++) {
				vc.image->getPixelRGBA(x, y, &r, &g, &b, &a);
				if (a > 0) {
					img->putPixel(x, y, (r + info.r) >> 1, (g + info.g) >> 1, (b + info.b) >> 1);
				}
			}
		}

		// In case of OpenGL backend, SDLImage needs to be converted
		info.overlay = m_renderbackend->createImage(img->detachSurface());
		delete img;

		if (info.overlay) {
			// mark overlay coloring as not dirty since we created it here
			info.dirty = false;
		}

		return info.overlay;
	}

	void InstanceRenderer::addOutlined(Instance* instance, int r, int g, int b, int width) {
		OutlineInfo newinfo;
		newinfo.r = r;
		newinfo.g = g;
		newinfo.b = b;
		newinfo.width = width;
		newinfo.dirty = true;

		// attempts to insert the element into the outline map
		// will return false in the second value of the pair if the instance already exists 
		// in the map and the first value of the pair will then be an iterator to the 
		// existing data for the instance
		std::pair<InstanceToOutlines_t::iterator, bool> insertiter = m_instance_outlines.insert(std::make_pair(instance, newinfo));

		if (insertiter.second == false) {
			// the insertion did not happen because the instance 
			// already exists in the map so lets just update its outline info
			OutlineInfo& info = insertiter.first->second;

			if (info.r != r || info.g != g || info.b != b || info.width != width) {
				// only update the outline info if its changed since the last call
				// flag the outline info as dirty so it will get processed during rendering
				info.r = r;
				info.b = b;
				info.g = g;
				info.width = width;
				info.dirty = true;
			}
		}
	}

	void InstanceRenderer::addColored(Instance* instance, int r, int g, int b) {
		ColoringInfo newinfo;
		newinfo.r = r;
		newinfo.g = g;
		newinfo.b = b;
		newinfo.dirty = true;

		// attempts to insert the element into the coloring map
		// will return false in the second value of the pair if the instance already exists 
		// in the map and the first value of the pair will then be an iterator to the 
		// existing data for the instance
		std::pair<InstanceToColoring_t::iterator, bool> insertiter = m_instance_colorings.insert(std::make_pair(instance, newinfo));

		if (insertiter.second == false) {
			// the insertion did not happen because the instance 
			// already exists in the map so lets just update its coloring info
			ColoringInfo& info = insertiter.first->second;

			if (info.r != r || info.g != g || info.b != b) {
				// only update the coloring info if its changed since the last call
				// flag the coloring info as dirty so it will get processed during rendering
				info.r = r;
				info.b = b;
				info.g = g;
				info.dirty = true;
			}
		}
	}

	void InstanceRenderer::removeOutlined(Instance* instance) {
		m_instance_outlines.erase(instance);
	}

	void InstanceRenderer::removeColored(Instance* instance) {
		m_instance_colorings.erase(instance);
	}

	void InstanceRenderer::removeAllOutlines() {
		m_instance_outlines.clear();
	}

	void InstanceRenderer::removeAllColored() {
		m_instance_colorings.clear();
	}

	void InstanceRenderer::reset() {
		removeAllOutlines();
		removeAllColored();
	}

}