logik/solver.hpp

#pragma once
#include "gamestate.hpp"

class Solver {
	Game known;
	int N, M;
	vector<Historic_guess> history = {};
public:
	Solver(int p_N, int p_M) : N(p_N), M(p_M), known({p_N, p_M}) {}

	// Guessing
	vector<int> guess() {
		// TODO
		return {};
	}

	// Utility functions
	// Prints what the solver deduced
	void print() {
		known.print();
	}
	// Clean guess and response from info we know
	Historic_guess clean(Historic_guess hist) {
		// The in-place colors we know
		for(int n = 0; n < N; n++) {
			if(known.final_color(n) == hist.guess[n]) {
				hist.guess[n] = -1;
				hist.response[1] -= 1;
			}
		}

		// The out-of-place colors we know
		for(int n = 0; n < N; n++) {
			if(hist.guess[n] == -1)
				continue;
			for(int i = 0; i < N; i++) {
				if(i == n)
					continue;
				if(known.final_color(i) == hist.guess[n]) {
					hist.guess[n] = -1;
					hist.response[0] -= 1;
				}
			}
		}

		return hist;
	}
	// For each color, get where it was guessed
	vector<vector<int>> get_positions_of_colors(vector<int> guess) {
		auto positions_of_colors = vector<vector<int>>(M, vector<int>(0));
		for(int n = 0; n < N; n++)
			if(guess[n] > -1)
				positions_of_colors[guess[n]].push_back(n);
		return positions_of_colors;
	}

	// Specific reactions
	void if_not_here_then_nowhere(vector<int> guess) {
		auto positions_of_colors = get_positions_of_colors(guess);

		// If color isn't here, it can't be in the sequence
		for(int col = 0; col < M; col++) {
			int possible_count = 0;
			for(int n : positions_of_colors[col])
				if(known.can(n, col))
					possible_count++;
			if(possible_count == 0 && positions_of_colors[col].size() > 0)
				known.empty_color(col);
		}
	}
	void here(vector<int> guess) {
		for(int n = 0; n < N; n++)
			if(guess[n] > -1 && known.can(n, guess[n]))
				known.must_be(n, guess[n]);
	}
	void not_here(vector<int> guess) {
		for(int n = 0; n < N; n++)
			if(guess[n] > -1)
				known.cannot_be(n, guess[n]);
	}
	void empty(vector<int> guess) {
		for(int col : guess)
			if(col > -1)
				known.empty_color(col);
	}
	void all_are_here(vector<int> guess) {
		auto positions_of_colors = get_positions_of_colors(guess);

		for(int col = 0; col < M; col++) {
			if(!positions_of_colors[col].size())
				known.empty_color(col);
		}
	}

	bool extract_info(Historic_guess hist) {
		bool something_to_learn = true;

		// A bit of cleaning
		auto cleaned = clean(hist);
		auto guess = cleaned.guess;
		auto response = cleaned.response;

		// Get number of colors, that can be on their positions
		int possible_count = 0;
		for(int n = 0; n < N; n++)
			if(guess[n] > -1 && known.can(n, guess[n]))
				possible_count++;

		// None of these colors are there
		if(response[0] == 0 && response[1] == 0) {
			empty(guess);
			something_to_learn = false;
		}

		// None at the right spot
		else if(response[1] == 0)
			not_here(guess);

		// At least only on the right spot
		else if(response[0] == 0) {
			// Only colors that can be on these positions are left
			if(response[1] == possible_count) {
				here(guess);
				something_to_learn = false;
			}
			else
				if_not_here_then_nowhere(guess);
		}

		// Nonzero / nonzero
		else {
			// Only colors that can be on these positions are left
			if(response[1] == possible_count)
				here(guess);
		}

		// All guessed colors are in the sequence
		if(response[0] + response[1] == N)
			all_are_here(guess);

		return something_to_learn;
	}
	void learn(vector<int> p_guess, vector<int> p_response) {
		// Write to history
		history.push_back({p_guess, p_response});

		// Repeat multiple times, if new information turned out
		for(auto _ : history)
			// Learn from previous guesses
			for(int i = 0; i < history.size(); i++)
				if(!extract_info(history[i])) {
					// If there is nothing left to learn from the guess
					history.erase(history.begin()+i);
					i--;
				}
	}
};