#ifndef LOADER_H
#define LOADER_H

#include <memory>
#include <string>
#include <vector>
#include "file_reader.h"
#include <stdexcept>

class Machine;

using std::shared_ptr;
using std::string;


class Loader {
public:
    Loader( shared_ptr<Machine> machine, string filename) : _machine(machine), _filename(filename) {
        _file_reader = std::make_shared<FileReader>(filename, std::ios::in);
        if (!_file_reader->good()) {
            throw std::runtime_error("Loader: failed to open file: " + filename);
        }
    }
    ~Loader();


    enum class RecordType {
        HEADER,
        TEXT,
        END,
        UNKNOWN
    };

    struct HeaderMetadata {
        string program_name;
        int start_address;
        int length;
    };
    struct TextRecord {
        int start_address;
        std::vector<uint8_t> data;
    };
    struct EndRecord {
        int execution_start_address;
    };

    void load();

private :

    static RecordType parseRecordType(char c);


    shared_ptr<Machine> _machine;
    string _filename;
    shared_ptr<FileReader> _file_reader;
    HeaderMetadata readHeader();
    TextRecord readTextRecord();
    EndRecord readEndRecord();
    bool load_into_memory(int start_address, const std::vector<uint8_t>& data);

};





#endif // LOADER_H