#ifndef REGISTERS_H
#define REGISTERS_H

#include <QObject>
#include <cstdint>

namespace machine {

class Registers : public QObject {
    Q_OBJECT
public:
    Registers();
    Registers(const Registers&);

    std::uint32_t read_pc() const; // Return current value of program counter
    std::uint32_t pc_inc(); // Increment program counter by four bytes
    std::uint32_t pc_jmp(std::int32_t offset); // Relative jump from current location in program counter
    void pc_abs_jmp(std::uint32_t address); // Absolute jump in program counter (write to pc)
    void pc_abs_jmp_28(std::uint32_t address); // Absolute jump in current 256MB section (basically J implementation)

    std::uint32_t read_gp(std::uint8_t i) const; // Read general-purpose register
    void write_gp(std::uint8_t i, std::uint32_t value); // Write general-purpose register
    std::uint32_t read_hi_lo(bool hi) const; // true - read HI / false - read LO
    void write_hi_lo(bool hi, std::uint32_t value);

    bool operator ==(const Registers &c) const;
    bool operator !=(const Registers &c) const;

    void reset(); // Reset all values to zero (except pc)

signals:
    void pc_update(std::uint32_t val);
    void gp_update(std::uint8_t i, std::uint32_t val);
    void hi_lo_update(bool hi, std::uint32_t val);

private:
    std::uint32_t gp[31]; // general-purpose registers ($0 is intentionally skipped)
    std::uint32_t hi, lo;
    std::uint32_t pc; // program counter
};

}

Q_DECLARE_METATYPE(machine::Registers)

#endif // REGISTERS_H