/*
 * population.cpp
 *
 *  Created on: Oct 12, 2010
 *      Author: mike
 *      for use in Yale course CPSC 427a, Fall 2010
 */

#include "population.hpp"

Population::Population(Algorithm alg, int numPlayers) :
    alg(alg), numPlayers(numPlayers), numOnes(0) {
    player = new Player*[numPlayers];
    for (int k = 0; k < numPlayers; k++) {
        switch (alg) {
        case fickleAlg:
            player[k] = new FicklePlayer();
            break;
        case crowdAlg:
            player[k] = new CrowdPlayer();
            break;
        default:
            fatal("Bad value of p.alg");
        }
    }
}

Population::~Population() {
    for (int k = 0; k < numPlayers; k++) {
        delete player[k];
    }
    delete [] player;
}

void Population::reset() {
    numOnes = 0;
    for (int k = 0; k < numPlayers; k++) {
        int preference = k & 1;
        player[k]->setPreference(preference);
        if (preference == 1)
            numOnes++;
    }
}

// Performs an update for the chosen sender-receiver pair.
// Only the receiver can change its choice.
// Invariant:  numOnes == sum_k player[k].getChoice().
void Population::oneStep(int sender, int receiver) {
    int msg = player[sender]->getChoice();
    int oldChoice = player[receiver]->getChoice();
    player[receiver]->receive(msg);
    int newChoice = player[receiver]->getChoice();
    numOnes += newChoice - oldChoice;
}

ostream& Population::print(ostream& out) const {
    out << "[Population:\n";
    out << "  algorithm=" << ((alg == fickleAlg) ? "fickle" : "crowd") << endl;
    out << "  numPlayers=" << numPlayers << "\n";
    out << "  numOnes=" << numOnes << "\n";
    out << "End Population]" << endl;
    return out;
}