#include <iostream>
#include <vector>
#include <fstream>
#include <regex>

std::string readTextFromFile(const std::string& fileName) {
    std::vector<std::string> lines;
    std::ifstream file(fileName);
    if (!file) {  // Überprüft, ob die Datei geöffnet werden konnte
        std::cerr << "Fehler: Datei konnte nicht geöffnet werden: " << fileName << std::endl;
        return "";
    }
    std::string result;
    std::string s;
    while(getline(file, s)) {
       result += s;
    }
    return result;
}

std::vector<std::string> determineValidMuls(std::string& content) {
    std::vector<std::string> validMuls;

    std::regex regex(R"(mul\(\d{1,3},\d{1,3}\))");
    auto begin = std::sregex_iterator(content.begin(), content.end(), regex);
    auto end = std::sregex_iterator();

    for(auto it = begin; it != end; ++it) {
        validMuls.push_back(it->str());
    }
    return validMuls;
}


int calcMultOfMultOp(const std::string& multOp) {
    std::regex regex("\\d{1,3}");
    auto begin = std::sregex_iterator(multOp.begin(), multOp.end(), regex);
    auto end = std::sregex_iterator();

    int multResult = 1;
    for(auto it = begin; it != end; ++it) {
        multResult *= std::stoi(it->str());
    }
    return multResult;
}

int calcMultSum(std::vector<std::string>& validMuls) {
    int sum = 0;
    for(const auto& mul : validMuls) {
        sum += calcMultOfMultOp(mul);
    }
    return sum;
}

int main() {
    std::string content = readTextFromFile("../input.txt");
    std::cout << content << std::endl;

    std::vector<std::string> validMuls = determineValidMuls(content);
    for(const auto& mul : validMuls) {
        std::cout << mul << std::endl;
    }

    int result = calcMultSum(validMuls);
    std::cout << "The correct Mult Result is: " << result << std::endl;
    return 0;
}