amit noob.cpp

#include "idManager.h"
#include <random>
#include <iostream>
#include <chrono>
#include "utils.h"

#define ID_BYTES    4
#define ID_LENGTH   (ID_BYTES) * 8

using namespace std;
using namespace std::chrono;

unsigned long long flipOrder(unsigned long long l) {
    unsigned long long res;

    int numOfBits = sizeof(long long) * 8;

    while (numOfBits-- > 0) {
        res <<= 1;
        res ^= l & 1;
        l >>= 1;
    }

    return res;
}

class RandomIdGenerator {
private:
    minstd_rand _engine;
    uniform_int_distribution<char> _distribution; // a byte distribution

public:

    RandomIdGenerator() : _distribution(0, 255) {
        // use current microseconds as a seed for the random generator
        chrono::microseconds ms = duration_cast<chrono::microseconds>(system_clock::now().time_since_epoch());

        unsigned long long seed = flipOrder(ms.count());
        _engine.seed(seed);
    }

    string randomId() {
        string output;

        int bytesRemaining = ID_BYTES;

        while (bytesRemaining-- > 0)
            output += _distribution(_engine);

        return output;
    }
};

RandomIdGenerator idGen;
map<string, ID*> ids = { };

bool idExists(const string& id) {
    // ids.find(id) returns ids.end() iff ids doesn't contain id
    return ids.find(id) != ids.end();
}

ID* getId(const string& id) {
    // this function gets a pointer to a given existing id
    return ids[id];
}

void registerId(const string& id) {
    // this function registers an id as a used id
    if (idExists(id)) {
        throw "Id already exists!";
    }


    ids[id] = nullptr;
}

void setId(const string& id, ID* object) {
    // this function adds an id object to the map
    ids[id] = object;
}

string nextId(const string& prefix) {
    // this function generates a new id
    string id;
    bool keep;

    do {
        id = prefix + idGen.randomId();
        keep = idExists(id);
    } while (idExists(id));

    return id;
}

BaseID::BaseID() : _id(nextId(string(""))) {
    setId(_id, this);
}

BaseID::BaseID(const type_info& type) : _id(nextId(type.name())) {
    setId(_id, this);
}

BaseID::BaseID(string& id) : _id(id) {
    setId(_id, this);
}

string BaseID::getID() {
    return _id;
}

BaseID::~BaseID() { /* empty destructor */ }

ostream& operator<<(ostream& out, ID& id) {
    printHexValue(out, id.getID());
    return out;
}