/*
 Copyright (c) 2013 yvt

 This file is part of OpenSpades.

 OpenSpades is free software: you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
 the Free Software Foundation, either version 3 of the License, or
 (at your option) any later version.

 OpenSpades 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 General Public License for more details.

 You should have received a copy of the GNU General Public License
 along with OpenSpades.  If not, see <http://www.gnu.org/licenses/>.

 */

#include <cstdint>
#include <new>

#include <Core/AutoLocker.h>
#include <Core/Debug.h>
#include <Core/Exception.h>
#include <Core/Mutex.h>
#include "AsyncRenderer.h"
#include "IImage.h"
#include "IModel.h"

namespace spades {
	namespace client {

#pragma mark - Commands

		class Command {
		public:
			uint16_t cmdSize;

			virtual void Execute(IRenderer *) = 0;
		};

		namespace rcmds {
			class Init : public Command {
			public:
				virtual void Execute(IRenderer *r) {
					SPADES_MARK_FUNCTION();
					r->Init();
				}
			};
			class Shutdown : public Command {
			public:
				virtual void Execute(IRenderer *r) {
					SPADES_MARK_FUNCTION();
					r->Shutdown();
				}
			};
			class SetGameMap : public Command {
			public:
				GameMap *map;
				virtual void Execute(IRenderer *r) {
					SPADES_MARK_FUNCTION();
					r->SetGameMap(map);
				}
			};
			class SetFogDistance : public Command {
			public:
				float v;
				virtual void Execute(IRenderer *r) {
					SPADES_MARK_FUNCTION();
					r->SetFogDistance(v);
				}
			};
			class SetFogColor : public Command {
			public:
				Vector3 v;
				virtual void Execute(IRenderer *r) {
					SPADES_MARK_FUNCTION();
					r->SetFogColor(v);
				}
			};
			class StartScene : public Command {
			public:
				SceneDefinition def;
				virtual void Execute(IRenderer *r) {
					SPADES_MARK_FUNCTION();
					r->StartScene(def);
				}
			};
			class AddLight : public Command {
			public:
				IImage *img;
				DynamicLightParam def;
				virtual void Execute(IRenderer *r) {
					SPADES_MARK_FUNCTION();
					if (img) {
						def.image = img;
						img = NULL;
					}
					try {
						r->AddLight(def);
					} catch (...) {
						if (img)
							img->Release();
						throw;
					}
					if (img) {
						img->Release();
					}
				}
			};
			class RenderModel : public Command {
			public:
				IModel *model;
				ModelRenderParam param;
				virtual void Execute(IRenderer *r) {
					try {
						r->RenderModel(model, param);
					} catch (...) {
						model->Release();
						model = NULL;
						throw;
					}
					model->Release();
					model = NULL;
				}
			};
			class AddDebugLine : public Command {
			public:
				Vector3 a, b;
				Vector4 color;
				virtual void Execute(IRenderer *r) {
					SPADES_MARK_FUNCTION();
					r->AddDebugLine(a, b, color);
				}
			};
			class AddSprite : public Command {
			public:
				IImage *img;
				Vector3 center;
				float radius, rotation;
				virtual void Execute(IRenderer *r) {
					SPADES_MARK_FUNCTION();
					try {
						r->AddSprite(img, center, radius, rotation);
					} catch (...) {
						img->Release();
						img = NULL;
						throw;
					}
					img->Release();
					img = NULL;
				}
			};
			class AddLongSprite : public Command {
			public:
				IImage *img;
				Vector3 p1, p2;
				float radius;
				virtual void Execute(IRenderer *r) {
					SPADES_MARK_FUNCTION();
					try {
						r->AddLongSprite(img, p1, p2, radius);
					} catch (...) {
						img->Release();
						img = NULL;
						throw;
					}
					img->Release();
					img = NULL;
				}
			};
			class EndScene : public Command {
			public:
				virtual void Execute(IRenderer *r) {
					SPADES_MARK_FUNCTION();
					r->EndScene();
				}
			};
			class MultiplyScreenColor : public Command {
			public:
				Vector3 v;
				virtual void Execute(IRenderer *r) {
					SPADES_MARK_FUNCTION();
					r->MultiplyScreenColor(v);
				}
			};
			class SetColor : public Command {
			public:
				Vector4 v;
				virtual void Execute(IRenderer *r) {
					SPADES_MARK_FUNCTION();
					r->SetColor(v);
				}
			};
			class SetColorAlphaPremultiplied : public Command {
			public:
				Vector4 v;
				virtual void Execute(IRenderer *r) {
					SPADES_MARK_FUNCTION();
					r->SetColorAlphaPremultiplied(v);
				}
			};
			class DrawImage : public Command {
			public:
				IImage *img;
				Vector2 outTopLeft;
				Vector2 outTopRight;
				Vector2 outBottomLeft;
				AABB2 inRect;
				virtual void Execute(IRenderer *r) {
					SPADES_MARK_FUNCTION();
					try {
						r->DrawImage(img, outTopLeft, outTopRight, outBottomLeft, inRect);
					} catch (...) {
						if (img)
							img->Release();
						img = NULL;
						throw;
					}
					if (img)
						img->Release();
					img = NULL;
				}
			};
			class DrawFlatGameMap : public Command {
			public:
				AABB2 outRect, inRect;
				virtual void Execute(IRenderer *r) {
					SPADES_MARK_FUNCTION();
					r->DrawFlatGameMap(outRect, inRect);
				}
			};
			class FrameDone : public Command {
			public:
				AsyncRenderer *arenderer;
				virtual void Execute(IRenderer *r) {
					SPADES_MARK_FUNCTION();
					r->FrameDone();
				}
			};
			class Flip : public Command {
			public:
				virtual void Execute(IRenderer *r) {
					SPADES_MARK_FUNCTION();
					r->Flip();
				}
			};
		};

#pragma mark - Command Buffer

		class AsyncRenderer::CmdBufferGenerator {
		public:
			std::vector<char> buffer;

			void Clear() { buffer.clear(); }

			template <typename T> T *AllocCommand() {
				SPADES_MARK_FUNCTION();

				size_t size = sizeof(T);
				size_t pos = buffer.size();
				buffer.resize(buffer.size() + size);

				void *dat = buffer.data() + pos;
				T *cmd = new (dat) T;
				cmd->cmdSize = sizeof(T);
				return cmd;
			}
		};

		class AsyncRenderer::CmdBufferReader {
			std::vector<char> buffer;
			size_t pos;

		public:
			CmdBufferReader(const std::vector<char> &buf) : buffer(buf), pos(0) {}
			Command *NextCommand() {
				SPADES_MARK_FUNCTION();

				if (pos >= buffer.size()) {
					return NULL;
				}
				Command *cmd = reinterpret_cast<Command *>(buffer.data() + pos);
				pos += cmd->cmdSize;
				if (pos > buffer.size()) {
					SPRaise("Truncated render command buffer");
				}
				return cmd;
			}
		};

		class AsyncRenderer::RenderDispatch : public ConcurrentDispatch {
			AsyncRenderer *renderer;

		public:
			std::vector<char> buffer;

			RenderDispatch(AsyncRenderer *renderer) : renderer(renderer) {}
			virtual void Run() {
				SPADES_MARK_FUNCTION();

				CmdBufferReader reader(buffer);
				Command *cmd;
				while ((cmd = reader.NextCommand()) != NULL) {
					cmd->Execute(renderer->base);
				}
			}
		};

		AsyncRenderer::AsyncRenderer(IRenderer *base, DispatchQueue *queue)
		    : base(base), queue(queue) {
			generator = new CmdBufferGenerator();
			dispatch = new RenderDispatch(this);
		}

		AsyncRenderer::~AsyncRenderer() {
			Sync();

			delete dispatch;
			delete generator;
		}

		void AsyncRenderer::FlushCommands() {
			if (generator->buffer.empty())
				return;

			dispatch->Join();
			dispatch->buffer = std::move(generator->buffer);
			generator->Clear();
			dispatch->StartOn(queue);
		}

		void AsyncRenderer::Sync() {
			FlushCommands();
			dispatch->Join();
		}

#pragma mark - General COmmands

		IImage *AsyncRenderer::RegisterImage(const char *filename) {
			SPADES_MARK_FUNCTION();

			class RegisterImageDispatch : public ConcurrentDispatch {
				IRenderer *base;
				const char *fn;
				IImage *result;
				std::string error;

			public:
				RegisterImageDispatch(IRenderer *base, const char *fn)
				    : base(base), fn(fn), result(NULL) {}
				virtual void Run() {
					try {
						result = base->RegisterImage(fn);
					} catch (const std::exception &ex) {
						error = ex.what();
					}
				}
				IImage *GetResult() {
					if (!error.empty()) {
						SPRaise("Error while RegisterImageDispatch:\n%s", error.c_str());
					} else {
						return result;
					}
				}
			};

			std::map<std::string, IImage *>::iterator it = images.find(filename);
			if (it == images.end()) {
				FlushCommands();
				RegisterImageDispatch dispatch(base, filename);
				dispatch.StartOn(queue);
				dispatch.Join();

				IImage *img = dispatch.GetResult();
				images[filename] = img;
				img->AddRef();
				return img;
			}
			it->second->AddRef();
			return it->second;
		}

		void AsyncRenderer::Init() {
			SPADES_MARK_FUNCTION();
			generator->AllocCommand<rcmds::Init>();
		}

		void AsyncRenderer::Shutdown() {
			SPADES_MARK_FUNCTION();
			generator->AllocCommand<rcmds::Shutdown>();
		}

		IImage *AsyncRenderer::CreateImage(spades::Bitmap *bmp) {
			SPADES_MARK_FUNCTION();

			class CreateImageDispatch : public ConcurrentDispatch {
				IRenderer *base;
				Bitmap *bmp;
				IImage *result;
				std::string error;

			public:
				CreateImageDispatch(IRenderer *base, Bitmap *bmp)
				    : base(base), bmp(bmp), result(NULL) {}
				virtual void Run() {
					try {
						result = base->CreateImage(bmp);
					} catch (const std::exception &ex) {
						error = ex.what();
					}
				}
				IImage *GetResult() {
					if (!error.empty()) {
						SPRaise("Error while CreateImageDispatch:\n%s", error.c_str());
					} else {
						return result;
					}
				}
			};

			FlushCommands();
			CreateImageDispatch dispatch(base, bmp);
			dispatch.StartOn(queue);
			dispatch.Join();
			IImage *img = dispatch.GetResult();
			return img;
		}

		IModel *AsyncRenderer::RegisterModel(const char *filename) {
			SPADES_MARK_FUNCTION();

			class RegisterModelDispatch : public ConcurrentDispatch {
				IRenderer *base;
				const char *fn;
				IModel *result;
				std::string error;

			public:
				RegisterModelDispatch(IRenderer *base, const char *fn)
				    : base(base), fn(fn), result(NULL) {}
				virtual void Run() {
					try {
						result = base->RegisterModel(fn);
					} catch (const std::exception &ex) {
						error = ex.what();
					}
				}
				IModel *GetResult() {
					if (!error.empty()) {
						SPRaise("Error while RegisterImageDispatch:\n%s", error.c_str());
					} else {
						return result;
					}
				}
			};

			std::map<std::string, IModel *>::iterator it = models.find(filename);
			if (it == models.end()) {
				FlushCommands();
				RegisterModelDispatch dispatch(base, filename);
				dispatch.StartOn(queue);
				dispatch.Join();
				IModel *img = dispatch.GetResult();
				models[filename] = img;
				img->AddRef();
				return img;
			}
			it->second->AddRef();
			return it->second;
		}

		IModel *AsyncRenderer::CreateModel(spades::VoxelModel *bmp) {
			SPADES_MARK_FUNCTION();

			class CreateModelDispatch : public ConcurrentDispatch {
				IRenderer *base;
				VoxelModel *bmp;
				IModel *result;
				std::string error;

			public:
				CreateModelDispatch(IRenderer *base, VoxelModel *bmp)
				    : base(base), bmp(bmp), result(NULL) {}
				virtual void Run() {
					try {
						result = base->CreateModel(bmp);
					} catch (const std::exception &ex) {
						error = ex.what();
					}
				}
				IModel *GetResult() {
					if (!error.empty()) {
						SPRaise("Error while CreateImageDispatch:\n%s", error.c_str());
					} else {
						return result;
					}
				}
			};

			FlushCommands();
			CreateModelDispatch dispatch(base, bmp);
			dispatch.StartOn(queue);
			dispatch.Join();
			IModel *img = dispatch.GetResult();
			return img;
		}

		void AsyncRenderer::SetGameMap(GameMap *gm) {
			SPADES_MARK_FUNCTION();
			rcmds::SetGameMap *cmd = generator->AllocCommand<rcmds::SetGameMap>();
			cmd->map = gm;
			Sync();
		}

		void AsyncRenderer::SetFogDistance(float distance) {
			SPADES_MARK_FUNCTION();
			rcmds::SetFogDistance *cmd = generator->AllocCommand<rcmds::SetFogDistance>();
			cmd->v = distance;
		}
		void AsyncRenderer::SetFogColor(Vector3 v) {
			SPADES_MARK_FUNCTION();
			rcmds::SetFogColor *cmd = generator->AllocCommand<rcmds::SetFogColor>();
			cmd->v = v;
		}

		void AsyncRenderer::StartScene(const SceneDefinition &def) {
			SPADES_MARK_FUNCTION();
			rcmds::StartScene *cmd = generator->AllocCommand<rcmds::StartScene>();
			cmd->def = def;
		}

		void AsyncRenderer::AddLight(const client::DynamicLightParam &light) {
			SPADES_MARK_FUNCTION();
			rcmds::AddLight *cmd = generator->AllocCommand<rcmds::AddLight>();
			if (light.image) {
				cmd->img = light.image;
				cmd->img->AddRef();
			} else {
				cmd->img = NULL;
			}
			cmd->def = light;
		}

		void AsyncRenderer::RenderModel(IModel *m, const ModelRenderParam &p) {
			SPADES_MARK_FUNCTION();
			rcmds::RenderModel *cmd = generator->AllocCommand<rcmds::RenderModel>();
			cmd->model = m;
			m->AddRef();
			cmd->param = p;
		}

		void AsyncRenderer::AddDebugLine(Vector3 a, Vector3 b, Vector4 color) {
			SPADES_MARK_FUNCTION();
			rcmds::AddDebugLine *cmd = generator->AllocCommand<rcmds::AddDebugLine>();
			cmd->a = a;
			cmd->b = b;
			cmd->color = color;
		}

		void AsyncRenderer::AddSprite(IImage *img, Vector3 center, float radius, float rotation) {
			SPADES_MARK_FUNCTION();
			rcmds::AddSprite *cmd = generator->AllocCommand<rcmds::AddSprite>();
			cmd->img = img;
			img->AddRef();
			cmd->center = center;
			cmd->radius = radius;
			cmd->rotation = rotation;
		}

		void AsyncRenderer::AddLongSprite(IImage *img, Vector3 p1, Vector3 p2, float radius) {
			SPADES_MARK_FUNCTION();
			rcmds::AddLongSprite *cmd = generator->AllocCommand<rcmds::AddLongSprite>();
			cmd->img = img;
			img->AddRef();
			cmd->p1 = p1;
			cmd->p2 = p2;
			cmd->radius = radius;
		}

		void AsyncRenderer::EndScene() {
			SPADES_MARK_FUNCTION();
			generator->AllocCommand<rcmds::EndScene>();
		}

		void AsyncRenderer::MultiplyScreenColor(Vector3 v) {
			SPADES_MARK_FUNCTION();
			rcmds::MultiplyScreenColor *cmd = generator->AllocCommand<rcmds::MultiplyScreenColor>();
			cmd->v = v;
		}

		void AsyncRenderer::SetColor(Vector4 c) {
			SPADES_MARK_FUNCTION();
			rcmds::SetColor *cmd = generator->AllocCommand<rcmds::SetColor>();
			cmd->v = c;
		}

		void AsyncRenderer::SetColorAlphaPremultiplied(Vector4 c) {
			SPADES_MARK_FUNCTION();
			rcmds::SetColorAlphaPremultiplied *cmd =
			  generator->AllocCommand<rcmds::SetColorAlphaPremultiplied>();
			cmd->v = c;
		}

		void AsyncRenderer::DrawImage(client::IImage *image, const spades::Vector2 &outTopLeft) {
			SPADES_MARK_FUNCTION();

			DrawImage(image, AABB2(outTopLeft.x, outTopLeft.y, image ? image->GetWidth() : 0,
			                       image ? image->GetHeight() : 0),
			          AABB2(0, 0, image ? image->GetWidth() : 0, image ? image->GetHeight() : 0));
		}

		void AsyncRenderer::DrawImage(client::IImage *image, const spades::AABB2 &outRect) {
			SPADES_MARK_FUNCTION();

			DrawImage(image, outRect,
			          AABB2(0, 0, image ? image->GetWidth() : 0, image ? image->GetHeight() : 0));
		}

		void AsyncRenderer::DrawImage(client::IImage *image, const spades::Vector2 &outTopLeft,
		                              const spades::AABB2 &inRect) {
			SPADES_MARK_FUNCTION();

			DrawImage(image,
			          AABB2(outTopLeft.x, outTopLeft.y, inRect.GetWidth(), inRect.GetHeight()),
			          inRect);
		}

		void AsyncRenderer::DrawImage(client::IImage *image, const spades::AABB2 &outRect,
		                              const spades::AABB2 &inRect) {
			SPADES_MARK_FUNCTION();

			DrawImage(image, Vector2::Make(outRect.GetMinX(), outRect.GetMinY()),
			          Vector2::Make(outRect.GetMaxX(), outRect.GetMinY()),
			          Vector2::Make(outRect.GetMinX(), outRect.GetMaxY()), inRect);
		}

		void AsyncRenderer::DrawImage(client::IImage *image, const spades::Vector2 &outTopLeft,
		                              const spades::Vector2 &outTopRight,
		                              const spades::Vector2 &outBottomLeft,
		                              const spades::AABB2 &inRect) {
			SPADES_MARK_FUNCTION();

			rcmds::DrawImage *cmd = generator->AllocCommand<rcmds::DrawImage>();
			cmd->img = image;
			if (image)
				image->AddRef();
			cmd->outTopLeft = outTopLeft;
			cmd->outTopRight = outTopRight;
			cmd->outBottomLeft = outBottomLeft;
			cmd->inRect = inRect;
		}

		void AsyncRenderer::DrawFlatGameMap(const spades::AABB2 &outRect,
		                                    const spades::AABB2 &inRect) {
			SPADES_MARK_FUNCTION();
			rcmds::DrawFlatGameMap *cmd = generator->AllocCommand<rcmds::DrawFlatGameMap>();
			cmd->outRect = outRect;
			cmd->inRect = inRect;
		}

		void AsyncRenderer::FrameDone() {
			generator->AllocCommand<rcmds::FrameDone>()->arenderer = this;
		}

		void AsyncRenderer::Flip() {
			generator->AllocCommand<rcmds::Flip>();
			FlushCommands();
		}

		Bitmap *AsyncRenderer::ReadBitmap() {
			FlushCommands();

			class ReadBitmapDispatch : public ConcurrentDispatch {
				IRenderer *base;
				Bitmap *result;
				std::string error;

			public:
				ReadBitmapDispatch(IRenderer *base) : base(base), result(NULL) {}
				virtual void Run() {
					try {
						result = base->ReadBitmap();
					} catch (const std::exception &ex) {
						error = ex.what();
					}
				}
				Bitmap *GetResult() {
					if (!error.empty()) {
						SPRaise("Error while CreateImageDispatch:\n%s", error.c_str());
					} else {
						return result;
					}
				}
			};

			ReadBitmapDispatch disp(base);
			disp.StartOn(queue);
			disp.Join();
			return disp.GetResult();
		}

		float AsyncRenderer::ScreenWidth() { return base->ScreenWidth(); }

		float AsyncRenderer::ScreenHeight() { return base->ScreenHeight(); }
	}
}