#pragma once

#include "deimos/core/std.h"
#include "deimos/core/gsl.h"

#define deimos_StaticAssert(...) static_assert(__VA_ARGS__, #__VA_ARGS__)

[[noreturn]]
inline void deimos_Trap()
{
    __builtin_trap();
}

#define deimos_Panic(MSG) do { deimos_Trap(); } while (0)

#define deimos_NO_COPY(TYPE)                            \
    TYPE(const TYPE&) = delete;                         \
    TYPE& operator=(const TYPE&) = delete;

#define deimos_NO_MOVE(TYPE)                            \
    TYPE(TYPE&&) = delete;                              \
    TYPE& operator=(TYPE&&) = delete;

#define deimos_NO_COPY_MOVE(TYPE)                       \
    deimos_NO_COPY(TYPE);                               \
    deimos_NO_MOVE(TYPE);

#define deimos_DEFAULT_COPY(TYPE)                       \
    TYPE(const TYPE&) = default;                        \
    TYPE& operator=(const TYPE&) = default;

#define deimos_DEFAULT_MOVE(TYPE)                       \
    TYPE(TYPE&&) = default;                             \
    TYPE& operator=(TYPE&&) = default;

#define deimos_DEFAULT_COPY_MOVE(TYPE)                  \
    deimos_DEFAULT_COPY(TYPE);                          \
    deimos_DEFAULT_MOVE(TYPE);

namespace deimos
{

struct uint128_t
{
    uint64_t high;
    uint64_t low;

    constexpr bool operator==(const uint128_t& other) const = default;
};

struct SourceLocation
{
    gsl::czstring   file;
    int32_t         line;

    constexpr SourceLocation( // NOLINT
        gsl::czstring file_ = __builtin_FILE(),
        int32_t line_ = __builtin_LINE()) :
        file{file_},
        line{line_}
    {}
};

template<typename T> T Min(T a, T b) { return (a < b) ? a : b; }
template<typename T> T Max(T a, T b) { return (a > b) ? a : b; }

[[maybe_unused]] static constexpr int64_t Kilobytes = 1024;
[[maybe_unused]] static constexpr int64_t Megabytes = 1024 * 1024;
[[maybe_unused]] static constexpr int64_t Gigabytes = 1024 * 1024 * 1024;

constexpr int64_t AlignUp(int64_t value, int64_t align)
{
    return __builtin_align_up(value, align);
}

template<typename T>
constexpr T* OffsetBytes(T* p, int64_t offset)
{
    return std::bit_cast<T*>(std::bit_cast<uintptr_t>(p) + std::bit_cast<uintptr_t>(offset));
}

constexpr void MemoryCopy(void* dst, const void* src, int64_t size)
{
    __builtin_memcpy(dst, src, (size_t)size);
}

inline void MemoryZero(void* dst, int64_t size)
{
    __builtin_memset(dst, 0, (size_t)size);
}

template<typename T, int64_t N>
constexpr int64_t ArraySize(const T (&)[N]) { return N; }

template<typename T>
class Span
{
    T*      m_begin = nullptr;
    int64_t m_size  = 0;

public:
    constexpr Span() = default;
    ~Span() = default;

    deimos_DEFAULT_COPY_MOVE(Span);

    constexpr Span(T* begin, int64_t size) :
        m_begin{begin},
        m_size{size}
    {
        Expects(size >= 0);
    }

    constexpr Span(std::initializer_list<T> list) :
        m_begin{list.begin()},
        m_size{(int64_t)list.size()}
    {}

    template<typename U>
    requires std::convertible_to<U*, T*>
    constexpr Span(const Span<U>& other) : // NOLINT(*-explicit-conversions)
        m_begin{other.begin()},
        m_size{other.size()}
    {}

    constexpr T* data() const { return m_begin; }
    constexpr T* begin() const { return m_begin; }
    constexpr T* end() const { return m_begin + m_size; } // NOLINT
    constexpr int64_t size() const { return m_size; }
    constexpr bool empty() const { return m_size == 0; }

    constexpr T& operator[](int64_t i) const
    {
        Expects(i >= 0 && i < m_size);
        return m_begin[i]; // NOLINT
    }
};

template<typename T>
inline Span<const std::byte> AsBytes(Span<T> span)
{
    return { reinterpret_cast<const std::byte*>(span.data()), span.size() * (int64_t)sizeof(T) };
}

class StringView
{
    const char*     m_begin = nullptr;
    int64_t         m_size  = 0;

public:
    constexpr StringView() = default;

    deimos_DEFAULT_COPY_MOVE(StringView);
    ~StringView() = default;

    constexpr StringView(gsl::czstring str) : // NOLINT(*-explicit-conversions)
        m_begin{str}, m_size{(int64_t)__builtin_strlen(str)}
    {}

    constexpr StringView(const char* begin, int64_t size) :
        m_begin{begin}, m_size{size}
    {}

    constexpr const char* data() const { return m_begin; }
    constexpr int64_t size() const { return m_size; }
    constexpr bool empty() const { return m_size == 0; }
};

inline Span<const std::byte> AsBytes(StringView span)
{
    return { reinterpret_cast<const std::byte*>(span.data()), span.size() };
}

deimos_StaticAssert(std::is_trivially_destructible_v<StringView>);
deimos_StaticAssert(std::is_trivially_copyable_v<StringView>);

} // namespace deimos