/*
 * RandomizeAutomaton.h
 *
 *  Created on: 9. 2. 2017
 *	  Author: Jan Travnicek
 */

#ifndef AUTOMATON_RANDOMIZE_H_
#define AUTOMATON_RANDOMIZE_H_

#include <core/multipleDispatch.hpp>

#include <automaton/Automaton.h>
#include <automaton/FSM/EpsilonNFA.h>
#include <automaton/FSM/MultiInitialStateNFA.h>
#include <automaton/FSM/NFA.h>
#include <automaton/FSM/DFA.h>

#include <algorithm>
#include <foreach>

namespace automaton {

namespace generate {

class RandomizeAutomaton : public std::SingleDispatch < RandomizeAutomaton, automaton::Automaton, const automaton::AutomatonBase & > {

	template < class T >
	static std::map < T, T > permutationMap ( const std::set < T > & data ) {
		std::vector < T > dataVector ( data.begin ( ), data.end ( ) );

		std::shuffle ( dataVector.begin ( ), dataVector.end ( ), std::random_devices::semirandom );
		std::map < T, T > permutation;
		for ( const std::tuple < const T &, const T & > & fromToPair : std::make_tuple_foreach ( data, dataVector ) ) {
			permutation.insert ( std::make_pair ( std::get < 0 > ( fromToPair ), std::get < 1 > ( fromToPair ) ) );
		}

		if(common::GlobalData::verbose)
			std::clog << "permutation map: " << permutation << std::endl;

		return permutation;
	}

public:
	static automaton::Automaton randomize ( const automaton::Automaton & automaton );

	template < class SymbolType, class EpsilonType, class StateType >
	static automaton::EpsilonNFA < SymbolType, EpsilonType, StateType > randomize( const automaton::EpsilonNFA < SymbolType, EpsilonType, StateType > & fsm );
	template < class SymbolType, class StateType >
	static automaton::MultiInitialStateNFA < SymbolType, StateType > randomize( const automaton::MultiInitialStateNFA < SymbolType, StateType > & fsm );
	template < class SymbolType, class StateType >
	static automaton::NFA < SymbolType, StateType > randomize( const automaton::NFA < SymbolType, StateType > & fsm );
	template < class SymbolType, class StateType >
	static automaton::DFA < SymbolType, StateType > randomize( const automaton::DFA < SymbolType, StateType > & fsm );
};

template < class SymbolType, class StateType >
automaton::DFA < SymbolType, StateType > RandomizeAutomaton::randomize(const automaton::DFA < SymbolType, StateType > & origFSM) {
	std::map < StateType, StateType > statePermutationMap = permutationMap ( origFSM.getStates ( ) );

	automaton::DFA < SymbolType, StateType > res ( statePermutationMap.find ( origFSM.getInitialState ( ) )->second );

	res.setStates ( origFSM.getStates ( ) );
	res.setInputAlphabet ( origFSM.getInputAlphabet ( ) );

	for ( const StateType & finalState : origFSM.getFinalStates ( ) )
		res.addFinalState ( statePermutationMap.find ( finalState )->second );

	for ( const std::pair < std::pair < StateType, SymbolType >, SymbolType > & transition : origFSM.getTransitions ( ) )
		res.addTransition ( statePermutationMap.find ( transition.first.first )->second, transition.first.second, statePermutationMap.find ( transition.second )->second );

	return res;
}

template < class SymbolType, class StateType >
automaton::MultiInitialStateNFA < SymbolType, StateType > RandomizeAutomaton::randomize(const automaton::MultiInitialStateNFA < SymbolType, StateType > & origFSM) {
	std::map < StateType, StateType > statePermutationMap = permutationMap ( origFSM.getStates ( ) );

	automaton::MultiInitialStateNFA < SymbolType, StateType > res;

	res.setStates ( origFSM.getStates ( ) );
	res.setInputAlphabet ( origFSM.getInputAlphabet ( ) );
	
	for ( const StateType & initialState : origFSM.getInitialStates ( ) )
		res.addInitialState ( statePermutationMap.find ( initialState )->second );

	for ( const StateType & finalState : origFSM.getFinalStates ( ) )
		res.addFinalState ( statePermutationMap.find ( finalState )->second );

	for ( const std::pair < std::pair < StateType, SymbolType >, std::set < SymbolType > > & transition : origFSM.getTransitions ( ) )
		for ( const StateType & target : transition.second )
			res.addTransition ( statePermutationMap.find ( transition.first.first )->second, transition.first.second, statePermutationMap.find ( target )->second );

	return res;
}

template < class SymbolType, class StateType >
automaton::NFA < SymbolType, StateType > RandomizeAutomaton::randomize(const automaton::NFA < SymbolType, StateType > & origFSM) {
	std::map < StateType, StateType > statePermutationMap = permutationMap ( origFSM.getStates ( ) );

	automaton::NFA < SymbolType, StateType > res ( statePermutationMap.find ( origFSM.getInitialState ( ) )->second );

	res.setStates ( origFSM.getStates ( ) );
	res.setInputAlphabet ( origFSM.getInputAlphabet ( ) );

	for ( const StateType & finalState : origFSM.getFinalStates ( ) )
		res.addFinalState ( statePermutationMap.find ( finalState )->second );

	for ( const std::pair < std::pair < StateType, SymbolType >, std::set < SymbolType > > & transition : origFSM.getTransitions ( ) )
		for ( const StateType & target : transition.second )
			res.addTransition ( statePermutationMap.find ( transition.first.first )->second, transition.first.second, statePermutationMap.find ( target )->second );

	return res;
}

template < class SymbolType, class EpsilonType, class StateType >
automaton::EpsilonNFA < SymbolType, EpsilonType, StateType > RandomizeAutomaton::randomize( const automaton::EpsilonNFA < SymbolType, EpsilonType, StateType > & origFSM ) {
	std::map < StateType, StateType > statePermutationMap = permutationMap ( origFSM.getStates ( ) );

	automaton::EpsilonNFA < SymbolType, EpsilonType, StateType > res ( statePermutationMap.find ( origFSM.getInitialState ( ) )->second );

	res.setStates ( origFSM.getStates ( ) );
	res.setInputAlphabet ( origFSM.getInputAlphabet ( ) );

	for ( const StateType & finalState : origFSM.getFinalStates ( ) )
		res.addFinalState ( statePermutationMap.find ( finalState )->second );

	for ( const std::pair < std::pair < StateType, std::variant < EpsilonType, SymbolType > >, std::set < SymbolType > > & transition : origFSM.getTransitions ( ) )
		for ( const StateType & target : transition.second )
			res.addTransition ( statePermutationMap.find ( transition.first.first )->second, transition.first.second, statePermutationMap.find ( target )->second );

	return res;
}

} /* namespace generate */

} /* namespace automaton */

#endif /* AUTOMATON_RANDOMIZE_H_ */