#include <vector>
#include <string>
#include <iostream>
#include "assignment4.h"
using std::cout;
using std::vector;
using std::string;
using std::endl;

int IntUnlimited::size() {return BFN.size();}
char IntUnlimited::at(int index) {return BFN.at(index);}
void IntUnlimited::push_back(char num) {return BFN.push_back(num);}
IntUnlimited IntUnlimited::negate() {
        if(this->BFN.at(0) == '-') {
            this->BFN.erase(0,1);
        }
        else {
            this->BFN.insert(0, "-");
        }
        return *this;
    }

IntUnlimited::IntUnlimited (const char* str) {
    string input = str;
    for(int i = 0; i < input.size(); ++i) {
        this->BFN.push_back(input.at(i));
    }

}

IntUnlimited::IntUnlimited (int num) {
    string str = To_String(num);
    for(int i = 0; i < str.size(); ++i) {
        this->BFN.push_back(str.at(i));
    }
}

IntUnlimited::IntUnlimited (const IntUnlimited &num) {
    BFN = num.BFN;
}
IntUnlimited::IntUnlimited(){

}

IntUnlimited operator+(IntUnlimited num1, IntUnlimited num2) {
    IntUnlimited output, i1, i2;
    if(num1.at(0) == '-' || num2.at(0) == '-') {
        if(num1.at(0) == '-' && num2.at(0) == '-') {
            return (num1.negate()+num2.negate()).negate();
        }
        else if(num1.at(0) == '-' && num2.at(0) != '-') {
            return (num1.negate() - num2).negate();
        }
        else {
            return (num2.negate() - num1).negate();
        }
    }
    if(num1.size() < num2.size() || ((num1.size() == num2.size())
       && (num1.at(0) < num2.at(0)))){
        i1 = num1;
        i2 = num2;
    }
    else{
        i1 = num2;
        i2 = num1;
    }

    int extra = 0;
    for(int x = 0; x < num2.size(); ++x){
        int numOut = (int)i1.at(i1.size()-1-x) + (int)i2.at(i2.size()-1-x) + extra;
        output.push_back((char)(numOut % 10));
        extra = numOut / 10;
    for(int x = num2.size(); x < num1.size(); ++x) {
        output.push_back((char)num1.at(x));
    }
    }

    return output;
}
IntUnlimited operator+(IntUnlimited num1, int num2) {
    IntUnlimited newNum2 = num2;
    return (num1+newNum2);
}
IntUnlimited operator-(IntUnlimited num1, IntUnlimited num2) {
    IntUnlimited output;
    if(num1.at(0) == '-' || num2.at(0) == '-') {
        if(num1.at(0) == '-' && num2.at(0) == '-'){
            return((num1.negate() - num2.negate()).negate());
        }
        else if(num1.at(0) == '-' && num2.at(0) != '-') {
            return(num1.negate()+num2).negate();
        }
        else if(num1.at(0) != '-' && num2.at(0) == '-') {
            return(num1 + num2.negate());
        }

    }
    if(num1.size() < num2.size() || ((num1.size() == num2.size())
    && (num1.at(0) < num2.at(0)))) {
        return ((num2-num1).negate());
    }

    int extra = 0;
    for(int i = 0; i < num2.size(); ++i) {
        int numOut = (int)num1.at(num1.size() - 1 - i) - (int)num2.at(num2.size() - 1 -i) - extra;
        if(numOut < 0) {
            output.push_back((char)(numOut*(-1)));
            extra = 1;
        }
        else {
            output.push_back((char)numOut);
        }

    }

    return output;
}
IntUnlimited operator-(IntUnlimited num1, int num2) {
    IntUnlimited newNum2 = num2;
    return (num1 - newNum2);
}

IntUnlimited operator*(IntUnlimited num1, IntUnlimited num2) {
    IntUnlimited output;
    long long int size1 = num1.size();
    long long int size2 = num2.size();
    if(num1.at(0) =='0' || num2.at(0) == '0') {
        return "0";
    }
    if(size1 < size2) {
        return num2*num1;
    }
    bool negAns = false;
    if(num1.at(0) == '-' && num2.at(0) == '-'){
        num1.negate();
        num2.negate();
    }
    else if(num1.at(0) == '-' && num2.at(0) != '-'){
        num1.negate();
        negAns = true;
    }
    else if(num1.at(0) != '-' && num2.at(0) == '-'){
        num2.negate();
        negAns = true;
    }
    int num1Index = 0;
    for (int i = size1-1; i >= 0; i--) {
        int extra = 0;
        int a = (int)num1.at(i);
        int num2Index = 0;
        for (int j = size2-1; j >= 0; j--) {
            int b = (int)num2.at(j);
            int numOut = a*b + extra;
            output.push_back((char)(numOut % 10));
            extra = numOut/10;
            num2Index++;
        }
        num1Index++;
    }
    if (negAns) {output.negate();}
    return output;
}

IntUnlimited operator*(IntUnlimited num1, int num2) {
    IntUnlimited newNum2 = num2;
    return num1 * newNum2;
}

IntUnlimited operator/(IntUnlimited num1, IntUnlimited num2) {
    IntUnlimited output;
    if(num2.at(0) == '0') {return "NaN";}
    if(num1.size() < num2.size()) {return "0";}
    bool negAns = false;
    if(num1.at(0) == '-' && num2.at(0) == '-'){
        num1.negate();
        num2.negate();
    }
    else if(num1.at(0) == '-' && num2.at(0) != '-'){
        num1.negate();
        negAns = true;
    }
    else if(num1.at(0) != '-' && num2.at(0) == '-'){
        num2.negate();
        negAns = true;
    }

    int i = 0;
    int curNum = num1.at(0);
    IntUnlimited n1 = num1;
    IntUnlimited n2 = num2;
    long long int quotient = 0;
    while(n1.at(0) != '0' || n1.at(0) != '-'){
        n1 = n1 - n2;
        quotient++;
    }
    output = quotient;
    if (negAns) {output.negate();}
    return output;
}

IntUnlimited operator/(IntUnlimited num1, int num2) {
    IntUnlimited newNum2 = num2;

    return num1 / num2;
}


string IntUnlimited::To_String(int num){
    string output;
    if(num < 0) {
        output.push_back('-');
        num = num * (-1);
    }
    if(num == 0) {
        output.push_back(0);
    }
    else{
        while(num != 0) {
            char lstDigit = (char)(num % 10);
            num = num / 10;
            output.push_back(lstDigit);
        }
    }
    return output;
}

int IntUnlimited::To_Int(string str){
    int output = 0;
    for(int i = 0; i < str.size(); ++i) {
        output = output*10 + str.at(i);
    }
    return output;
}