#ifndef MATADOR_UUID_HPP
#define MATADOR_UUID_HPP

#include <array>
#include <string>
#include <cstdint>

namespace matador::utils {

class uuid {
public:
    using uuid_array = std::array<uint32_t, 4>;

    // Default constructor initializes to zero
    uuid() = default;

    // Static UUID v4 generator
    static uuid generate();

    // Returns UUID as a string
    [[nodiscard]] std::string str() const;

    // Access to internal data
    [[nodiscard]] const uuid_array& data() const;

    // Reset UUID to zero
    void clear() { _data.fill(0); }

    // Comparisons
    friend bool operator==(const uuid& lhs, const uuid& rhs);
    friend bool operator!=(const uuid& lhs, const uuid& rhs);
    friend bool operator<(const uuid& lhs, const uuid& rhs);

private:
    uuid_array _data{0, 0, 0, 0};
};
}

// Hash specialization to allow use in unordered containers
template <>
struct std::hash<matador::utils::uuid> {
    std::size_t operator()(const matador::utils::uuid& u) const noexcept {
        std::size_t h = 0;
        for (uint32_t val : u.data()) {
            h ^= std::hash<uint32_t>{}(val) + 0x9e3779b9 + (h << 6) + (h >> 2);
        }
        return h;
    }
};

#endif //MATADOR_UUID_HPP