/*
 * =====================================================================================
 *
 *  OpenMiner
 *
 *  Copyright (C) 2018-2020 Unarelith, Quentin Bazin <openminer@unarelith.net>
 *  Copyright (C) 2019-2020 the OpenMiner contributors (see CONTRIBUTORS.md)
 *
 *  This file is part of OpenMiner.
 *
 *  OpenMiner 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.
 *
 *  OpenMiner 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 OpenMiner; if not, write to the Free Software Foundation, Inc.,
 *  51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA
 *
 * =====================================================================================
 */
#include <gk/core/GameClock.hpp>

#include "EngineConfig.hpp"
#include "Network.hpp"
#include "Server.hpp"
#include "ServerCommandHandler.hpp"
#include "ServerPlayer.hpp"
#include "ServerWorld.hpp"

void ServerWorld::update() {
	if (m_lastTick < gk::GameClock::getTicks() / 50) {
		m_lastTick = gk::GameClock::getTicks() / 50;

		for (auto &it : m_chunks) {
			it.second->tick(*this, *m_server);

			if (it.second->areAllNeighboursLoaded())
				it.second->updateLights();

			if (it.second->isInitialized() && !it.second->isSent()) {
				for (auto &client : m_server->server().info().clients())
					sendChunkData(client, it.second.get());

				// DEBUG("Chunk updated at", it.second->x(), it.second->y(), it.second->z());
			}
		}
	}
}

void ServerWorld::createChunkNeighbours(ServerChunk *chunk) {
	gk::Vector3i surroundingChunks[6] = {
		{chunk->x() - 1, chunk->y(),     chunk->z()},
		{chunk->x() + 1, chunk->y(),     chunk->z()},
		{chunk->x(),     chunk->y() - 1, chunk->z()},
		{chunk->x(),     chunk->y() + 1, chunk->z()},
		{chunk->x(),     chunk->y(),     chunk->z() - 1},
		{chunk->x(),     chunk->y(),     chunk->z() + 1},
	};

	for (u8 i = 0 ; i < 6 ; ++i) {
		// Check if this neighbour already exists, if yes then skip it
		ServerChunk *neighbour = (ServerChunk *)getChunk(surroundingChunks[i].x, surroundingChunks[i].y, surroundingChunks[i].z);
		if (neighbour) {
			// Assign surrounding chunk pointers
			chunk->setSurroundingChunk(i, neighbour);
			neighbour->setSurroundingChunk((i % 2 == 0) ? i + 1 : i - 1, chunk);

			continue;
		}

		// Create our neighbour
		auto it = m_chunks.emplace(
			gk::Vector3i{
				surroundingChunks[i].x,
				surroundingChunks[i].y,
				surroundingChunks[i].z
			},
			new ServerChunk{
				surroundingChunks[i].x,
				surroundingChunks[i].y,
				surroundingChunks[i].z,
				*this
			}
		);

		// Get the created neighbour
		neighbour = it.first->second.get();

		// Assign surrounding chunk pointers
		chunk->setSurroundingChunk(i, neighbour);
		neighbour->setSurroundingChunk((i % 2 == 0) ? i + 1 : i - 1, chunk);
	}
}

void ServerWorld::sendChunkData(const ClientInfo &client, ServerChunk *chunk) {
	sf::Packet packet;
	packet << Network::Command::ChunkData;
	packet << chunk->x() << chunk->y() << chunk->z();
	for (u16 z = 0 ; z < CHUNK_HEIGHT ; ++z) {
		for (u16 y = 0 ; y < CHUNK_DEPTH ; ++y) {
			for (u16 x = 0 ; x < CHUNK_WIDTH ; ++x) {
				packet << chunk->data()[z][y][x];
				packet << chunk->lightmap().getLightData(x, y, z);

				BlockData *blockData = chunk->getBlockData(x, y, z);
				if (blockData) {
					s32 globalX = x + chunk->x() * CHUNK_WIDTH;
					s32 globalY = y + chunk->y() * CHUNK_DEPTH;
					s32 globalZ = z + chunk->z() * CHUNK_HEIGHT;

					m_server->sendBlockDataUpdate(globalX, globalY, globalZ, blockData, &client);
					m_server->sendBlockInvUpdate(globalX, globalY, globalZ, blockData->inventory, &client);
				}
			}
		}
	}

	client.tcpSocket->send(packet);
	chunk->setSent(true);
	chunk->setChanged(false);

	// std::cout << "Chunk at (" << chunk->x() << ", " << chunk->y() << ", " << chunk->z() << ") sent to client" << std::endl;
}

void ServerWorld::sendRequestedData(ClientInfo &client, int cx, int cy, int cz) {
	ServerChunk *chunk = (ServerChunk *)getChunk(cx, cy, cz);
	if (!chunk) {
		auto it = m_chunks.emplace(gk::Vector3i{cx, cy, cz}, new ServerChunk(cx, cy, cz, *this));
		chunk = it.first->second.get();
	}

	// Create our neighbours so that we can generate and process lights correctly
	createChunkNeighbours(chunk);

	// Generate our chunk
	if (!chunk->isInitialized()) {
		m_terrainGenerator.generate(*chunk);

		chunk->setInitialized(true);
	}

	chunk->updateLights();

	sendChunkData(client, chunk);
}

Chunk *ServerWorld::getChunk(int cx, int cy, int cz) const {
	auto it = m_chunks.find({cx, cy, cz});
	if (it == m_chunks.end())
		return nullptr;

	return it->second.get();
}