main.cpp

// main.cpp
#include "calcs/calc.hpp"
#include <queue>
#include <memory>
#include <fstream>
#include <iostream>
#include <string>
#include <vector>
#include <sstream>
#include <stack>
#include <emscripten/bind.h>

using namespace emscripten;

class chart {
public:
    double sa_points;
    std::string song_name;
    int level;
    int score;
    chart(std::string n, int s, int l) { //constructor
        song_name = n;
        level = l;
        score = s;
        sa_points = calculate_sa(level, score);
    }

    std::string formatPrint() const {
        return song_name + "\t" + std::to_string(level) + "\t" + std::to_string(score) + "\t" + std::to_string(sa_points) + "\n";
    }
};

std::vector<std::string> splitLines(const std::string& text) {
    std::vector<std::string> lines;
    std::stringstream ss(text);
    std::string line;
    while(std::getline(ss, line)) {
        lines.push_back(line);
    }
    return lines;
}


std::vector<std::string> parseCSVLine(const std::string& line) {
    std::vector<std::string> fields;
    fields.push_back(line);
    return fields;
}

struct CompareCharts {
    bool operator()(const std::shared_ptr<chart>& a,const std::shared_ptr<chart>& b) const {
        return a->sa_points > b->sa_points; // min-heap (largest sa stays)
    }
};

// This function takes the entire CSV contents as one string and returns the output
std::string process_csv_string(const std::string& csv_contents) {
    auto lines = splitLines(csv_contents);

    std::priority_queue<std::shared_ptr<chart>, std::vector<std::shared_ptr<chart>>, CompareCharts> min_heap;
    std::stack<std::shared_ptr<chart>> top30;

    bool firstline = true;
    for (const auto& line : lines) {
        std::vector<std::string> fields = parseCSVLine(line);

        for (const std::string& field : fields) {
            if (!firstline) {
                std::stringstream ss(field);
                std::string segment;
                std::vector<std::string> segments;
                while (std::getline(ss, segment, '\t')) {  // split by tab as in original
                    segments.push_back(segment);
                }

                // Defensive checks (in case CSV formatting is slightly different)
                if (segments.size() < 5) {
                    continue;
                }

                std::string name = segments[1];
                int level = 0;
                int score = 0;
                try {
                    level = std::stoi(segments[3]);
                    score = std::stoi(segments[4]);
                } catch (...) {
                    // skip bad lines
                    continue;
                }

                auto c = std::make_shared<chart>(name, score, level);

                if (min_heap.size() == 30) {
                    if (c->sa_points > min_heap.top()->sa_points) {
                        min_heap.pop();
                        min_heap.push(c);
                    }
                } else {
                    min_heap.push(c);
                }
            } else {
                firstline = false;
            }
        }
    }

    while(!min_heap.empty()) {
        top30.push(min_heap.top());
        min_heap.pop();
    }

    double sum = 0.0;
    std::ostringstream out;
    out << "Here are your top 30 songs used for SA calc: \n";
    while(!top30.empty()) {
        out << top30.top()->formatPrint();
        sum += top30.top()->sa_points;
        top30.pop();
    }

    double points = (sum / 30.0);
    out << "\n \n";
    out << "your total SA is: " << sum << ". And your avg SA in top 30 is: " << points << "\n";

    return out.str();
}

// Bindings for embind
EMSCRIPTEN_BINDINGS(sa_module) {
    emscripten::function("process_csv_string", &process_csv_string);
}