#include "Polinom.h"

Polinom::Polinom()
{
    _poli.push_back(new Monom());
}
Polinom::Polinom(const Polinom& dreapta) {
    for (int i = 0; i < dreapta._poli.size(); ++i)
        _poli.push_back(new Monom(*dreapta._poli[i]));
}
Polinom::~Polinom() {
    for (int i = 0; i < _poli.size(); ++i)
        delete(Monom*) _poli[i];
}

int Polinom::gradPolinom() {
    return _poli[0]->grad;
}

float Polinom::evaluare(float x) {
    float sum = 0;
    for (int i = 0; i < _poli.size(); ++i)
        sum += _poli[i]->coeficient * pow(x, _poli[i]->grad);

    return sum;
}

void Polinom::stergeZero() {
    if (_poli.size() == 1)
        return;
    vector<Monom*>::iterator start = _poli.begin(), sfarsit = _poli.end() - 1;
    do {
        --sfarsit;
        if (Monom::esteZero(*sfarsit)) {
            if (start == sfarsit) {
                _poli.erase(sfarsit);
                return;
            }
            auto aux = sfarsit;
            --sfarsit;
            _poli.erase(aux);
            ++sfarsit;
        }
    } while (sfarsit != start);
}

void Polinom::add(float c, int g)
{
    Monom* deAdaugat = new Monom(c, g);
    vector<Monom*>::iterator loc = upper_bound(_poli.begin(), _poli.end(), deAdaugat, Monom::comparatie);
    if ((*loc)->grad == g) {
        (*loc)->coeficient += c;
        return;
    }

    _poli.insert(loc, deAdaugat);
}

Polinom Polinom::operator*(float scalar) {
    if (abs(scalar) < FLT_EPSILON)
        return Polinom();
    Polinom out = *this;
    for (int i = 0; i < _poli.size(); ++i)
        out._poli[i]->coeficient *= scalar;
    return out;
}

Polinom Polinom::operator+(const Polinom& dreapta) {
    Polinom out;
    int i = 0, j = 0;

    while (i < _poli.size() && j < dreapta._poli.size()) {

        if (_poli[i]->grad == dreapta._poli[j]->grad) {
            out.add(_poli[i]->coeficient + dreapta._poli[j]->coeficient, _poli[i]->grad);
            ++i;
            ++j;
            continue;
        }
        if (_poli[i]->grad < dreapta._poli[j]->grad) {
            out.add(_poli[i]->coeficient, _poli[i]->grad);
            ++i;
            continue;
        }
        out.add(dreapta._poli[j]->coeficient, dreapta._poli[j]->grad);
        ++j;
    }
    while (i < _poli.size()) {
        out.add(_poli[i]->coeficient, _poli[i]->grad);
        ++i;
    }

    while (j < dreapta._poli.size()) {
        out.add(dreapta._poli[j]->coeficient, dreapta._poli[j]->grad);
        ++j;
    }

    out.stergeZero();
    return out;
}

istream& operator>>(istream& is, Polinom& p) {
    int g;
    float c;
    int monoame;

    cout << "Numar monoame: "; is >> monoame;

    for (int i = 0; i < monoame; ++i) {
        is >> c >> g;
        p.add(c, g);
    }
    is.get();

    return is;
}

ostream& operator<<(ostream& os, Polinom& p) {
    int sfarsit = (p._poli.size() == 1) ? 1 : p._poli.size()-1;
    for (int i = 0; i < sfarsit; ++i)
        os << "(" << p._poli[i]->coeficient << " " << p._poli[i]->grad << ") ";
    os << endl;

    return os;
}