// Copyright 2015 Citra Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.

#pragma once

#include <cstddef>
#include <type_traits>
#include "common/bit_field.h"
#include "common/common_funcs.h"
#include "common/common_types.h"

#define LCD_REG_INDEX(field_name) (offsetof(LCD::Regs, field_name) / sizeof(u32))

namespace LCD {

struct Regs {

    union ColorFill {
        u32 raw;

        BitField<0, 8, u32> color_r;
        BitField<8, 8, u32> color_g;
        BitField<16, 8, u32> color_b;
        BitField<24, 1, u32> is_enabled;
    };

    INSERT_PADDING_WORDS(0x81);
    ColorFill color_fill_top;
    INSERT_PADDING_WORDS(0xE);
    u32 backlight_top;

    INSERT_PADDING_WORDS(0x1F0);

    ColorFill color_fill_bottom;
    INSERT_PADDING_WORDS(0xE);
    u32 backlight_bottom;
    INSERT_PADDING_WORDS(0x16F);

    static constexpr std::size_t NumIds() {
        return sizeof(Regs) / sizeof(u32);
    }

    const u32& operator[](int index) const {
        const u32* content = reinterpret_cast<const u32*>(this);
        return content[index];
    }

    u32& operator[](int index) {
        u32* content = reinterpret_cast<u32*>(this);
        return content[index];
    }
};
static_assert(std::is_standard_layout<Regs>::value, "Structure does not use standard layout");

// TODO: MSVC does not support using offsetof() on non-static data members even though this
//       is technically allowed since C++11. This macro should be enabled once MSVC adds
//       support for that.
#ifndef _MSC_VER
#define ASSERT_REG_POSITION(field_name, position)                                                  \
    static_assert(offsetof(Regs, field_name) == position * 4,                                      \
                  "Field " #field_name " has invalid position")

ASSERT_REG_POSITION(color_fill_top, 0x81);
ASSERT_REG_POSITION(backlight_top, 0x90);
ASSERT_REG_POSITION(color_fill_bottom, 0x281);
ASSERT_REG_POSITION(backlight_bottom, 0x290);

#undef ASSERT_REG_POSITION
#endif // !defined(_MSC_VER)

extern Regs g_regs;

template <typename T>
void Read(T& var, const u32 addr);

template <typename T>
void Write(u32 addr, const T data);

/// Initialize hardware
void Init();

/// Shutdown hardware
void Shutdown();

} // namespace LCD