#pragma once

#include <unordered_map>
#include <vector>

#include "command.h"
#include "either.h"


using namespace std;


class KeyInputMachine{
	struct TreeNode{
		Command *cmd=nullptr;
		unordered_map<int,TreeNode*> *m=nullptr;

		~TreeNode();
	};

	TreeNode root;
	TreeNode *current=&root;

public:
	KeyInputMachine();
	KeyInputMachine(const vector<pair<vector<int>,Command>> &list);
	KeyInputMachine(const KeyInputMachine&) = delete;

	//Overwrites if already existent; ambiguous-prefix bindings not permitted
	//at the moment
	void insert(const vector<int> &keys,const Command &cmd);

	//If Left, then true indicates 'still possibilities'; false indicates 'no more
	//possible sequences left, error'
	Either<bool,Command> input(int key);

	//Cancel the current input combination
	void cancel();
};

extern KeyInputMachine global_keyinput;