/*
 Copyright (c) 2013 yvt
 based on code of pysnip (c) Mathias Kaerlev 2011-2012.

 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 <algorithm>
#include <cmath>
#include <cstdlib>
#include <vector>

#include "GameMap.h"
#include <Core/AutoLocker.h>
#include <Core/Debug.h>
#include <Core/Exception.h>
#include <Core/FileManager.h>
#include <Core/IStream.h>

namespace spades {
	namespace client {

		GameMap::GameMap() {
			SPADES_MARK_FUNCTION();

			for (int x = 0; x < DefaultWidth; x++)
				for (int y = 0; y < DefaultHeight; y++) {
					solidMap[x][y] = 1; // ground only
					for (int z = 0; z < DefaultDepth; z++) {
						uint32_t col = 0x00284067;
						col ^= 0x070707 & static_cast<uint32_t>(mt_engine());
						colorMap[x][y][z] = col + (100UL * 0x1000000UL);
					}
				}
		}
		GameMap::~GameMap() { SPADES_MARK_FUNCTION(); }

		void GameMap::AddListener(spades::client::IGameMapListener *l) {
			AutoLocker guard(&listenersMutex);
			listeners.push_back(l);
		}

		void GameMap::RemoveListener(spades::client::IGameMapListener *l) {
			AutoLocker guard(&listenersMutex);
			auto it = std::find(listeners.begin(), listeners.end(), l);
			if (it != listeners.end()) {
				listeners.erase(it);
			}
		}

		bool GameMap::IsSurface(int x, int y, int z) {
			if (!IsSolid(x, y, z))
				return false;
			if (z == 0)
				return true;
			if (x > 0 && !IsSolid(x - 1, y, z))
				return true;
			if (x < Width() - 1 && !IsSolid(x + 1, y, z))
				return true;
			if (y > 0 && !IsSolid(x, y - 1, z))
				return true;
			if (y < Height() - 1 && !IsSolid(x, y + 1, z))
				return true;
			if (!IsSolid(x, y, z - 1))
				return true;
			if (z < Depth() - 1 && !IsSolid(x, y, z + 1))
				return true;
			return false;
		}

		static void WriteColor(std::vector<char> &buffer, int color) {
			buffer.push_back((char)(color >> 16));
			buffer.push_back((char)(color >> 8));
			buffer.push_back((char)(color >> 0));
			buffer.push_back((char)(color >> 24));
		}

		// base on pysnip
		void GameMap::Save(spades::IStream *stream) {
			int w = Width();
			int h = Height();
			int d = Depth();
			std::vector<char> buffer;
			buffer.reserve(10 * 1024 * 1024);
			for (int y = 0; y < h; y++) {
				for (int x = 0; x < w; x++) {
					int k = 0;
					while (k < d) {
						int z;

						int air_start;
						int top_colors_start;
						int top_colors_end; // exclusive
						int bottom_colors_start;
						int bottom_colors_end; // exclusive
						int top_colors_len;
						int bottom_colors_len;
						int colors;
						air_start = k;
						while (k < d && !IsSolid(x, y, k))
							++k;
						top_colors_start = k;
						while (k < d && IsSurface(x, y, k))
							++k;
						top_colors_end = k;

						while (k < d && IsSolid(x, y, k) && !IsSurface(x, y, k))
							++k;

						bottom_colors_start = k;

						z = k;
						while (z < d && IsSurface(x, y, z))
							++z;

						if (z != d) {
							while (IsSurface(x, y, k))
								++k;
						}
						bottom_colors_end = k;

						top_colors_len = top_colors_end - top_colors_start;
						bottom_colors_len = bottom_colors_end - bottom_colors_start;

						colors = top_colors_len + bottom_colors_len;

						if (k == d) {
							buffer.push_back(0);
						} else {
							buffer.push_back(colors + 1);
						}
						buffer.push_back(top_colors_start);
						buffer.push_back(top_colors_end - 1);
						buffer.push_back(air_start);

						for (z = 0; z < top_colors_len; ++z) {
							WriteColor(buffer, GetColor(x, y, top_colors_start + z));
						}
						for (z = 0; z < bottom_colors_len; ++z) {
							WriteColor(buffer, GetColor(x, y, bottom_colors_start + z));
						}
					}
				}
			}
			stream->Write(buffer.data(), buffer.size());
		}

		bool GameMap::ClipBox(int x, int y, int z) {
			int sz;

			if (x < 0 || x >= 512 || y < 0 || y >= 512)
				return true;
			else if (z < 0)
				return false;
			sz = (int)z;
			if (sz == 63)
				sz = 62;
			else if (sz >= 64)
				return true;
			return IsSolid((int)x, (int)y, sz);
		}

		bool GameMap::ClipWorld(int x, int y, int z) {
			int sz;

			if (x < 0 || x >= 512 || y < 0 || y >= 512)
				return 0;
			if (z < 0)
				return 0;
			sz = (int)z;
			if (sz == 63)
				sz = 62;
			else if (sz >= 63)
				return 1;
			else if (sz < 0)
				return 0;
			return IsSolid((int)x, (int)y, sz);
		}

		bool GameMap::ClipBox(float x, float y, float z) {
			SPAssert(!std::isnan(x));
			SPAssert(!std::isnan(y));
			SPAssert(!std::isnan(z));
			return ClipBox((int)floorf(x), (int)floorf(y), (int)floorf(z));
		}

		bool GameMap::ClipWorld(float x, float y, float z) {
			SPAssert(!std::isnan(x));
			SPAssert(!std::isnan(y));
			SPAssert(!std::isnan(z));
			return ClipWorld((int)floorf(x), (int)floorf(y), (int)floorf(z));
		}

		bool GameMap::CastRay(spades::Vector3 v0, spades::Vector3 v1, float length,
		                      spades::IntVector3 &vOut) {
			SPADES_MARK_FUNCTION_DEBUG();

			SPAssert(!std::isnan(v0.x));
			SPAssert(!std::isnan(v0.y));
			SPAssert(!std::isnan(v0.z));
			SPAssert(!std::isnan(v1.x));
			SPAssert(!std::isnan(v1.y));
			SPAssert(!std::isnan(v1.z));
			SPAssert(!std::isnan(length));

			v1 = v0 + v1 * length;

			Vector3 f, g;
			IntVector3 a, c, d, p, i;
			long cnt = 0;

			a = v0.Floor();
			c = v1.Floor();

			if (c.x < a.x) {
				d.x = -1;
				f.x = v0.x - a.x;
				g.x = (v0.x - v1.x) * 1024;
				cnt += a.x - c.x;
			} else if (c.x != a.x) {
				d.x = 1;
				f.x = a.x + 1 - v0.x;
				g.x = (v1.x - v0.x) * 1024;
				cnt += c.x - a.x;
			} else {
				d.x = 0;
				f.x = g.x = 0;
			}
			if (c.y < a.y) {
				d.y = -1;
				f.y = v0.y - a.y;
				g.y = (v0.y - v1.y) * 1024;
				cnt += a.y - c.y;
			} else if (c.y != a.y) {
				d.y = 1;
				f.y = a.y + 1 - v0.y;
				g.y = (v1.y - v0.y) * 1024;
				cnt += c.y - a.y;
			} else {
				d.y = 0;
				f.y = g.y = 0;
			}
			if (c.z < a.z) {
				d.z = -1;
				f.z = v0.z - a.z;
				g.z = (v0.z - v1.z) * 1024;
				cnt += a.z - c.z;
			} else if (c.z != a.z) {
				d.z = 1;
				f.z = a.z + 1 - v0.z;
				g.z = (v1.z - v0.z) * 1024;
				cnt += c.z - a.z;
			} else {
				d.z = 0;
				f.z = g.z = 0;
			}

			Vector3 pp =
			  MakeVector3(f.x * g.z - f.z * g.x, f.y * g.z - f.z * g.y, f.y * g.x - f.x * g.y);
			p = pp.Floor();
			i = g.Floor();

			if (cnt > (long)length)
				cnt = (long)length;

#if 1
			// faster version
			uint64_t lastSolidMap = solidMap[a.x & (DefaultWidth - 1)][a.y & (DefaultHeight - 1)];
			if (a.z < 0 && d.z < 0) {
				return false;
			} else if (a.z < 0) {
				while (cnt > 0 && a.z < 0) {
					if (((p.x | p.y) >= 0) && (a.z != c.z)) {
						a.z += d.z;
						p.x -= i.x;
						p.y -= i.y;
					} else if ((p.z >= 0) && (a.x != c.x)) {
						a.x += d.x;
						p.x += i.z;
						p.z -= i.y;
					} else {
						a.y += d.y;
						p.y += i.z;
						p.z += i.x;
					}
					cnt--;
				}
			} else if (a.z >= 64) {
				vOut = a;
				return true;
			}
			while (cnt > 0) {
				if (((p.x | p.y) >= 0) && (a.z != c.z)) {
					a.z += d.z;
					p.x -= i.x;
					p.y -= i.y;
					if (a.z < 0 && d.z < 0) {
						return false;
					} else if (a.z >= 64) {
						vOut = a;
						return true;
					}
				} else if ((p.z >= 0) && (a.x != c.x)) {
					a.x += d.x;
					p.x += i.z;
					p.z -= i.y;
					lastSolidMap = solidMap[a.x & (DefaultWidth - 1)][a.y & (DefaultHeight - 1)];
				} else {
					a.y += d.y;
					p.y += i.z;
					p.z += i.x;
					lastSolidMap = solidMap[a.x & (DefaultWidth - 1)][a.y & (DefaultHeight - 1)];
				}

				if ((lastSolidMap >> (uint64_t)a.z) & 1ULL) {
					vOut = a;
					return true;
				}
				cnt--;
			}
#else
			while (cnt > 0) {
				if (((p.x | p.y) >= 0) && (a.z != c.z)) {
					a.z += d.z;
					p.x -= i.x;
					p.y -= i.y;
				} else if ((p.z >= 0) && (a.x != c.x)) {
					a.x += d.x;
					p.x += i.z;
					p.z -= i.y;
				} else {
					a.y += d.y;
					p.y += i.z;
					p.z += i.x;
				}

				if (IsSolidWrapped(a.x, a.y, a.z)) {
					vOut = a;
					return true;
				}
				cnt--;
			}
#endif
			return false;
		}

		GameMap::RayCastResult GameMap::CastRay2(spades::Vector3 v0, spades::Vector3 dir,
		                                         int maxSteps) {
			SPADES_MARK_FUNCTION_DEBUG();
			GameMap::RayCastResult result;

			SPAssert(!std::isnan(v0.x));
			SPAssert(!std::isnan(v0.y));
			SPAssert(!std::isnan(v0.z));
			SPAssert(!std::isnan(dir.x));
			SPAssert(!std::isnan(dir.y));
			SPAssert(!std::isnan(dir.z));

			dir = dir.Normalize();

			spades::IntVector3 iv = v0.Floor();
			spades::Vector3 fv;
			if (IsSolidWrapped(iv.x, iv.y, iv.z)) {
				result.hit = true;
				result.startSolid = true;
				result.hitPos = v0;
				result.hitBlock = iv;
				result.normal = IntVector3::Make(0, 0, 0);
				return result;
			}

			if (dir.x > 0.f) {
				fv.x = (float)(iv.x + 1) - v0.x;
			} else {
				fv.x = v0.x - (float)iv.x;
			}
			if (dir.y > 0.f) {
				fv.y = (float)(iv.y + 1) - v0.y;
			} else {
				fv.y = v0.y - (float)iv.y;
			}
			if (dir.z > 0.f) {
				fv.z = (float)(iv.z + 1) - v0.z;
			} else {
				fv.z = v0.z - (float)iv.z;
			}

			float invX = dir.x;
			float invY = dir.y;
			float invZ = dir.z;

			if (invX != 0.f)
				invX = 1.f / fabsf(invX);
			if (invY != 0.f)
				invY = 1.f / fabsf(invY);
			if (invZ != 0.f)
				invZ = 1.f / fabsf(invZ);

			for (int i = 0; i < maxSteps; i++) {
				IntVector3 nextBlock;
				int hasNextBlock = 0;
				float nextBlockTime = 0.f;

				if (invX != 0.f) {
					nextBlock = iv;
					if (dir.x > 0.f)
						nextBlock.x++;
					else
						nextBlock.x--;
					nextBlockTime = fv.x * invX;
					hasNextBlock = 1;
				}
				if (invY != 0.f) {
					float t = fv.y * invY;
					if (!hasNextBlock || t < nextBlockTime) {
						nextBlock = iv;
						if (dir.y > 0.f)
							nextBlock.y++;
						else
							nextBlock.y--;
						nextBlockTime = t;
						hasNextBlock = 2;
					}
				}
				if (invZ != 0.f) {
					float t = fv.z * invZ;
					if (!hasNextBlock || t < nextBlockTime) {
						nextBlock = iv;
						if (dir.z > 0.f)
							nextBlock.z++;
						else
							nextBlock.z--;
						nextBlockTime = t;
						hasNextBlock = 3;
					}
				}
				SPAssert(hasNextBlock != 0);  // must hit a plane
				SPAssert(hasNextBlock == 1 || // x-plane
				         hasNextBlock == 2 || // y-plane
				         hasNextBlock == 3);  // z-plane

				if (hasNextBlock == 1) {
					fv.x = 1.f;
				} else {
					fv.x -= fabsf(dir.x) * nextBlockTime;
				}
				if (hasNextBlock == 2) {
					fv.y = 1.f;
				} else {
					fv.y -= fabsf(dir.y) * nextBlockTime;
				}
				if (hasNextBlock == 3) {
					fv.z = 1.f;
				} else {
					fv.z -= fabsf(dir.z) * nextBlockTime;
				}

				result.hitBlock = nextBlock;
				result.normal = iv - nextBlock;

				if (IsSolidWrapped(nextBlock.x, nextBlock.y, nextBlock.z)) {
					// hit.
					Vector3 hitPos;
					if (dir.x > 0.f) {
						hitPos.x = (float)(nextBlock.x + 1) - fv.x;
					} else {
						hitPos.x = (float)nextBlock.x + fv.x;
					}
					if (dir.y > 0.f) {
						hitPos.y = (float)(nextBlock.y + 1) - fv.y;
					} else {
						hitPos.y = (float)nextBlock.y + fv.y;
					}
					if (dir.z > 0.f) {
						hitPos.z = (float)(nextBlock.z + 1) - fv.z;
					} else {
						hitPos.z = (float)nextBlock.z + fv.z;
					}

					result.hit = true;
					result.startSolid = false;
					result.hitPos = hitPos;
					return result;
				} else {
					iv = nextBlock;
				}
			}

			result.hit = false;
			result.startSolid = false;
			result.hitPos = v0;
			return result;
		}

		static uint32_t swapColor(uint32_t col) {
			union {
				uint8_t bytes[4];
				uint32_t c;
			} u;
			u.c = col;
			std::swap(u.bytes[0], u.bytes[2]);
			return (u.c & 0xffffff) | (100UL * 0x1000000);
		}

		GameMap *GameMap::Load(spades::IStream *stream) {
			SPADES_MARK_FUNCTION();

			std::string bytes = stream->ReadAllBytes();
			size_t len = bytes.size();
			size_t pos = 0;

			GameMap *map = new GameMap();
			try {
				for (int y = 0; y < 512; y++) {
					for (int x = 0; x < 512; x++) {
						map->solidMap[x][y] = 0xffffffffffffffffULL;

						if (pos + 2 >= len) {
							SPRaise("File truncated");
						}

						int z = 0;
						for (;;) {
							int i;
							uint32_t *color;
							int number_4byte_chunks = bytes[pos];
							int top_color_start = bytes[pos + 1];
							int top_color_end = bytes[pos + 2];
							int bottom_color_start;
							int bottom_color_end;
							int len_top;
							int len_bottom;

							for (i = z; i < top_color_start; i++)
								map->Set(x, y, i, false, 0, true);

							if (pos + 4 + top_color_end - top_color_start + 3 >= len) {
								SPRaise("File truncated");
							}

							color = (uint32_t *)(bytes.data() + pos + 4);
							for (z = top_color_start; z <= top_color_end; z++)
								map->Set(x, y, z, true, swapColor(*(color++)), true);

							if (top_color_end == 62) {
								map->Set(x, y, 63, true, map->GetColor(x, y, 62), true);
							}

							len_bottom = top_color_end - top_color_start + 1;

							if (number_4byte_chunks == 0) {
								pos += 4 * (len_bottom + 1);
								break;
							}

							len_top = (number_4byte_chunks - 1) - len_bottom;

							pos += (int)bytes[pos] * 4;

							if (pos + 3 >= len) {
								SPRaise("File truncated");
							}

							bottom_color_end = bytes[pos + 3];
							bottom_color_start = bottom_color_end - len_top;

							for (z = bottom_color_start; z < bottom_color_end; z++) {
								uint32_t col = swapColor(*(color++));
								map->Set(x, y, z, true, col, true);
							}
							if (bottom_color_end == 63) {
								map->Set(x, y, 63, true, map->GetColor(x, y, 62), true);
							}
						}
					}
				}

				return map;
			} catch (...) {
				delete map;
				throw;
			}
		}
	}
}