spatial_storage.h

/*
Multiscale Universal Interface Code Coupling Library

Copyright (C) 2017 Y. H. Tang, S. Kudo, X. Bian, Z. Li, G. E. Karniadakis

This software is jointly licensed under the Apache License, Version 2.0
and the GNU General Public License version 3, you may use it according
to either.

** Apache License, version 2.0 **

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.

** GNU General Public License, version 3 **

This program 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.

This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.

** File Details **

Filename: spatial_storage.h
Created: Apr 21, 2014
Author: S. Kudo
Description:
*/

#define SPATIAL_STORAGE_H

#include <exception>
#include <mutex>
#include "dynstorage.h"
#include "virtual_container.h"

namespace mui {

template<typename BIN, typename STORAGE, typename CONFIG>
class spatial_storage {
private: // type definitions
	using storage_t = STORAGE;
public:
	using point_type = typename CONFIG::point_type;
	using EXCEPTION = typename CONFIG::EXCEPTION;

private: // functors
	struct insert_ { 
		template<typename T> void operator()( T& t ){
			T& rhs = storage_cast<T&>(st);
			t.insert(t.end(), std::make_move_iterator(rhs.begin()), std::make_move_iterator(rhs.end()));
		}
		storage_t st;
	};
	struct construct_ {
		template<typename T> void operator()(T& t){ ::new(ptr) BIN(t); }
		void* ptr;
	};
public:
	spatial_storage() noexcept {
		is_bin_ = false;
	}
	~spatial_storage() {
		destroy_if_bin_();
	}
	spatial_storage( const spatial_storage& rhs ): data_(rhs.data_) {
		is_bin_.store(rhs.is_bin_.load());
		if( rhs.is_built() ) ::new(&bin_) BIN(rhs.bin_);
	}
	spatial_storage( spatial_storage&& rhs ) noexcept : data_(std::move(rhs.data_)) {
		is_bin_.store(rhs.is_bin_.load());
		if( rhs.is_built() ) ::new(&bin_) BIN(std::move(rhs.bin_));
		rhs.destroy_if_bin_();
	}
	spatial_storage( storage_t rhs ): data_(std::move(rhs)) {
		is_bin_ = false;
	}
	spatial_storage& operator=( spatial_storage rhs ) {
		rhs.swap(*this);
		return *this;
	}
	
	void swap( spatial_storage& rhs ) noexcept(noexcept(BIN(std::move(rhs.bin_)))) {
		data_.swap(rhs.data_);
		if( is_bin_ && rhs.is_bin_ ) bin_.swap(rhs.bin_);
		else if( is_bin_ && !rhs.is_bin_ ) {
			::new(&(rhs.bin_)) BIN(std::move(bin_));
			rhs.is_bin_ = true;
			destroy_if_bin_();
		} else if( !is_bin_ && rhs.is_bin_ ) {
			::new(&(bin_)) BIN(std::move(rhs.bin_));
			is_bin_ = true;
			rhs.destroy_if_bin_();
		}
	}
	

	// no lock internally; it's job of uniface because
	// we need more large lock if there is no rw-lock.
	template<typename REGION, typename FOCUS, typename SAMPLER, typename ... ADDITIONAL>
	typename SAMPLER::OTYPE 
	query(const REGION& reg, const FOCUS& f, const SAMPLER& s, ADDITIONAL && ... addtional) const {
		using vec = std::vector<std::pair<point_type,typename SAMPLER::ITYPE> >;
		if( data_.empty() ) 
			return s.filter( f, virtual_container<typename SAMPLER::ITYPE,CONFIG>(vec(),std::vector<bool>()), addtional... );
		if( !is_built() ) EXCEPTION(std::logic_error("spatial storage: query error. "
		                                             "Bin was not built yet. Internal data was corrupsed."));
		const vec& st = storage_cast<const vec&>(data_);
		return s.filter( f, virtual_container<typename SAMPLER::ITYPE,CONFIG>(st,bin_.query(reg)), addtional...);
	}
	/*template<typename REGION, typename FOCUS, typename SAMPLER>
	typename SAMPLER::OTYPE 
	query2(const REGION& reg, const FOCUS& f, const SAMPLER& s) const {
		using vec = std::vector<std::pair<point_type,typename SAMPLER::ITYPE> >;
		if( data_.empty() ) 
			return s.filter(f, vec());
		if( !is_built() ) EXCEPTION( std::logic_error("spatial storage: query error. "
		                                               "not builded bin. Internal data was corrupsed.") );
		const vec& st= storage_cast<const vec&>(data_);
		return s.filter(f,bin_.query2(reg,st));
	}*/
	void build() {
		if( is_built() ) EXCEPTION(std::logic_error("spatial storage: build error. cannot build twice."));
		if( !data_.empty() ){
			data_.apply_visitor(construct_{(void*)&bin_});
			is_bin_ = true;
		}
	}
	template<typename REGION, typename FOCUS, typename SAMPLER, typename ...ADDITIONAL>
	typename SAMPLER::OTYPE 
	build_and_query_ts(const REGION& reg, const FOCUS& f, const SAMPLER& s, ADDITIONAL && ... additional) {
		// this method is thread-safe. other methods are not.
		{
			std::unique_lock<std::mutex> lock(mutex_);
			if( !is_built() ) build();
		}
		return query(reg, f, s, additional...);
	}
	void insert( storage_t storage ) {
		destroy_if_bin_();
		if( !storage ) return;
		if( !data_ ) data_ = std::move(storage);
		else if( data_.which() == storage.which() ) data_.apply_visitor(insert_{storage});
		else EXCEPTION(bad_storage_id("spatial storage: insert error. Type doesn't match."));
	}
	
	bool is_built() const { return is_bin_; }
	bool empty() const { return data_.empty(); }
private:
	void destroy_if_bin_() { 
		if( is_built() ) {
			bin_.~BIN(); 
			is_bin_ = false;
		}
	}

	storage_t data_;

	std::atomic<bool> is_bin_;
	union {
		char nodata_ = '\0';
		BIN bin_;
	};
	mutable std::mutex mutex_;
};
}

#define SPATIAL_STORAGE_H