#include "global.h"
#include "constants/songs.h"
#include "constants/weather.h"
#include "constants/rgb.h"
#include "util.h"
#include "event_object_movement.h"
#include "field_weather.h"
#include "main.h"
#include "menu.h"
#include "palette.h"
#include "random.h"
#include "script.h"
#include "start_menu.h"
#include "sound.h"
#include "sprite.h"
#include "task.h"
#include "trig.h"
#include "gpu_regs.h"

#define MACRO1(color) ((((color) >> 1) & 0xF) | (((color) >> 2) & 0xF0) | (((color) >> 3) & 0xF00))

enum
{
    GAMMA_NONE,
    GAMMA_NORMAL,
    GAMMA_ALT,
};

struct RGBColor
{
    u16 r:5;
    u16 g:5;
    u16 b:5;
};

struct WeatherPaletteData
{
    u16 gammaShiftColors[8][0x1000]; // 0x1000 is the number of bytes that make up all palettes.
};

struct WeatherCallbacks
{
    void (*initVars)(void);
    void (*main)(void);
    void (*initAll)(void);
    bool8 (*finish)(void);
};

// This file's functions.
/*static*/ bool8 LightenSpritePaletteInFog(u8);
/*static*/ void BuildGammaShiftTables(void);
/*static*/ void UpdateWeatherGammaShift(void);
/*static*/ void ApplyGammaShift(u8 startPalIndex, u8 numPalettes, s8 gammaIndex);
/*static*/ void ApplyGammaShiftWithBlend(u8 startPalIndex, u8 numPalettes, s8 gammaIndex, u8 blendCoeff, u16 blendColor);
/*static*/ void ApplyDroughtGammaShiftWithBlend(s8 gammaIndex, u8 blendCoeff, u16 blendColor);
/*static*/ void ApplyFogBlend(u8 blendCoeff, u16 blendColor);
/*static*/ bool8 FadeInScreen_RainShowShade(void);
/*static*/ bool8 FadeInScreen_Drought(void);
/*static*/ bool8 FadeInScreen_Fog1(void);
/*static*/ void FadeInScreenWithWeather(void);
/*static*/ void DoNothing(void);
void None_Init(void);
void None_Main(void);
bool8 None_Finish(void);
void Clouds_InitVars(void);
void Clouds_Main(void);
void Clouds_InitAll(void);
bool8 Clouds_Finish(void);
void Weather2_InitVars(void);
void Weather2_Main(void);
void Weather2_InitAll(void);
bool8 Weather2_Finish(void);
void LightRain_InitVars(void);
void LightRain_Main(void);
void LightRain_InitAll(void);
bool8 LightRain_Finish(void);
void Snow_InitVars(void);
void Snow_Main(void);
void Snow_InitAll(void);
bool8 Snow_Finish(void);
void MedRain_InitVars(void);
void Rain_Main(void);
void MedRain_InitAll(void);
bool8 Rain_Finish(void);
void Fog1_InitVars(void);
void Fog1_Main(void);
void Fog1_InitAll(void);
bool8 Fog1_Finish(void);
void Ash_InitVars(void);
void Ash_Main(void);
void Ash_InitAll(void);
bool8 Ash_Finish(void);
void Sandstorm_InitVars(void);
void Sandstorm_Main(void);
void Sandstorm_InitAll(void);
bool8 Sandstorm_Finish(void);
void Fog2_InitVars(void);
void Fog2_Main(void);
void Fog2_InitAll(void);
bool8 Fog2_Finish(void);
void Fog1_InitVars(void);
void Fog1_Main(void);
void Fog1_InitAll(void);
bool8 Fog1_Finish(void);
void Shade_InitVars(void);
void Shade_Main(void);
void Shade_InitAll(void);
bool8 Shade_Finish(void);
void Drought_InitVars(void);
void Drought_Main(void);
void Drought_InitAll(void);
bool8 Drought_Finish(void);
void HeavyRain_InitVars(void);
void Rain_Main(void);
void HeavyRain_InitAll(void);
bool8 Rain_Finish(void);
void Bubbles_InitVars(void);
void Bubbles_Main(void);
void Bubbles_InitAll(void);
bool8 Bubbles_Finish(void);

// Const rom data

// This is a pointer to gWeather. All code in this file accesses gWeather directly,
// while code in other field weather files accesses gWeather through this pointer.
// This is likely the result of compiler optimization, since using the pointer in
// this file produces the same result as accessing gWeather directly.
struct Weather *const gWeatherPtr = &gWeather;

/*static*/ const struct WeatherCallbacks sWeatherFuncs[] =
{
    {None_Init,          None_Main,      None_Init,         None_Finish},
    {Clouds_InitVars,    Clouds_Main,    Clouds_InitAll,    Clouds_Finish},
    {Weather2_InitVars,  Weather2_Main,  Weather2_InitAll,  Weather2_Finish},
    {LightRain_InitVars, LightRain_Main, LightRain_InitAll, LightRain_Finish},
    {Snow_InitVars,      Snow_Main,      Snow_InitAll,      Snow_Finish},
    {MedRain_InitVars,   Rain_Main,      MedRain_InitAll,   Rain_Finish},
    {Fog1_InitVars,      Fog1_Main,      Fog1_InitAll,      Fog1_Finish},
    {Ash_InitVars,       Ash_Main,       Ash_InitAll,       Ash_Finish},
    {Sandstorm_InitVars, Sandstorm_Main, Sandstorm_InitAll, Sandstorm_Finish},
    {Fog2_InitVars,      Fog2_Main,      Fog2_InitAll,      Fog2_Finish},
    {Fog1_InitVars,      Fog1_Main,      Fog1_InitAll,      Fog1_Finish},
    {Shade_InitVars,     Shade_Main,     Shade_InitAll,     Shade_Finish},
    {Drought_InitVars,   Drought_Main,   Drought_InitAll,   Drought_Finish},
    {HeavyRain_InitVars, Rain_Main,      HeavyRain_InitAll, Rain_Finish},
    {Bubbles_InitVars,   Bubbles_Main,   Bubbles_InitAll,   Bubbles_Finish},
};

void (*const gWeatherPalStateFuncs[])(void) =
{
    UpdateWeatherGammaShift, // WEATHER_PAL_STATE_CHANGING_WEATHER
    FadeInScreenWithWeather, // WEATHER_PAL_STATE_SCREEN_FADING_IN
    DoNothing,               // WEATHER_PAL_STATE_SCREEN_FADING_OUT
    DoNothing,               // WEATHER_PAL_STATE_IDLE
};

// This table specifies which of the gamma shift tables should be
// applied to each of the background and sprite palettes.
/*static*/ const u8 sBasePaletteGammaTypes[32] =
{
    // background palettes
    GAMMA_NORMAL,
    GAMMA_NORMAL,
    GAMMA_NORMAL,
    GAMMA_NORMAL,
    GAMMA_NORMAL,
    GAMMA_NORMAL,
    GAMMA_NORMAL,
    GAMMA_NORMAL,
    GAMMA_NORMAL,
    GAMMA_NORMAL,
    GAMMA_NORMAL,
    GAMMA_NORMAL,
    GAMMA_NORMAL,
    GAMMA_NORMAL,
    GAMMA_NONE,
    GAMMA_NONE,
    // sprite palettes
    GAMMA_ALT,
    GAMMA_NORMAL,
    GAMMA_ALT,
    GAMMA_ALT,
    GAMMA_ALT,
    GAMMA_ALT,
    GAMMA_NORMAL,
    GAMMA_NORMAL,
    GAMMA_NORMAL,
    GAMMA_NORMAL,
    GAMMA_ALT,
    GAMMA_NORMAL,
    GAMMA_NORMAL,
    GAMMA_NORMAL,
    GAMMA_NORMAL,
    GAMMA_NORMAL,
};


// EWRAM
EWRAM_DATA struct Weather gWeather = {0};
EWRAM_DATA u8 gFieldEffectPaletteGammaTypes[32] = {0};

// IWRAM bss
IWRAM_DATA const u8 *sPaletteGammaTypes;
IWRAM_DATA u32 filler_03000f54;

// const
extern const u16 gUnknown_083970E8[];
extern const u16 gUnknown_0854014C[][4096];

// code
void StartWeather(void)
{
    if (!FuncIsActiveTask(Task_WeatherMain))
    {
        u8 index = AllocSpritePalette(0x1200);
        CpuCopy32(gUnknown_083970E8, &gPlttBufferUnfaded[0x100 + index * 16], 32);
        BuildGammaShiftTables();
        gWeather.altGammaSpritePalIndex = index;
        gWeather.weatherPicSpritePalIndex = AllocSpritePalette(0x1201);
        gWeather.rainSpriteCount = 0;
        gWeather.unknown_6D8 = 0;
        gWeather.cloudSpritesCreated = 0;
        gWeather.snowflakeSpriteCount = 0;
        gWeather.ashSpritesCreated = 0;
        gWeather.fog1SpritesCreated = 0;
        gWeather.fog2SpritesCreated = 0;
        gWeather.sandstormSprites1Created = 0;
        gWeather.sandstormSprites2Created = 0;
        gWeather.unknown_72E = 0;
        gWeather.lightenedFogSpritePalsCount = 0;
        Weather_SetBlendCoeffs(16, 0);
        gWeather.currWeather = 0;
        gWeather.palProcessingState = WEATHER_PAL_STATE_IDLE;
        gWeather.readyForInit = FALSE;
        gWeather.weatherChangeComplete = TRUE;
        gWeather.taskId = CreateTask(Task_WeatherInit, 80);
    }
}

void ChangeWeather(u8 weather)
{
    if (weather != WEATHER_RAIN_LIGHT && weather != WEATHER_RAIN_MED && weather != WEATHER_RAIN_HEAVY)
    {
        PlayRainSoundEffect();
    }

    if (gWeather.nextWeather != weather && gWeather.currWeather == weather)
    {
        sWeatherFuncs[weather].initVars();
    }

    gWeather.weatherChangeComplete = FALSE;
    gWeather.nextWeather = weather;
    gWeather.finishStep = 0;
}

void sub_80AB104(u8 weather)
{
    PlayRainSoundEffect();
    gWeather.currWeather = weather;
    gWeather.nextWeather = weather;
}

void sub_80AB130(u8 weather)
{
    PlayRainSoundEffect();
    gWeather.currWeather = weather;
    gWeather.nextWeather = weather;
    gWeather.readyForInit = TRUE;
}

void Task_WeatherInit(u8 taskId)
{
    // Waits until it's ok to initialize weather.
    // When the screen fades in, this is set to TRUE.
    if (gWeather.readyForInit)
    {
        sWeatherFuncs[gWeather.currWeather].initAll();
        gTasks[taskId].func = Task_WeatherMain;
    }
}

void Task_WeatherMain(u8 taskId)
{
    if (gWeather.currWeather != gWeather.nextWeather)
    {
        if (!sWeatherFuncs[gWeather.currWeather].finish() && gWeather.palProcessingState != WEATHER_PAL_STATE_SCREEN_FADING_OUT)
        {
            // Finished cleaning up previous weather. Now transition to next weather.
            sWeatherFuncs[gWeather.nextWeather].initVars();
            gWeather.gammaStepFrameCounter = 0;
            gWeather.palProcessingState = WEATHER_PAL_STATE_CHANGING_WEATHER;
            gWeather.currWeather = gWeather.nextWeather;
            gWeather.weatherChangeComplete = TRUE;
        }
    }
    else
    {
        sWeatherFuncs[gWeather.currWeather].main();
    }

    gWeatherPalStateFuncs[gWeather.palProcessingState]();
}

void None_Init(void)
{
    gWeather.gammaTargetIndex = 0;
    gWeather.gammaStepDelay = 0;
}

void None_Main(void)
{
}

u8 None_Finish(void)
{
    return 0;
}

// Builds two tables that contain gamma shifts for palette colors.
// It's unclear why the two tables aren't declared as const arrays, since
// this function always builds the same two tables.
/*static*/ void BuildGammaShiftTables(void)
{
    u16 v0;
    u8 (*v1)[32];
    u16 v2;
    u16 v4;
    u16 v5;
    u16 v6;
    u16 v9;
    u32 v10;
    u16 v11;
    s16 dunno;

    sPaletteGammaTypes = sBasePaletteGammaTypes;
    for (v0 = 0; v0 <= 1; v0++)
    {
        if (v0 == 0)
            v1 = gWeather.gammaShifts;
        else
            v1 = gWeather.altGammaShifts;

        for (v2 = 0; v2 < 32; v2++)
        {
            v4 = v2 << 8;
            if (v0 == 0)
                v5 = (v2 << 8) / 16;
            else
                v5 = 0;
            for (v6 = 0; v6 <= 2; v6++)
            {
                v4 = (v4 - v5);
                v1[v6][v2] = v4 >> 8;
            }
            v9 = v4;
            v10 = 0x1f00 - v4;
            if ((0x1f00 - v4) < 0)
            {
                v10 += 0xf;
            }
            v11 = v10 >> 4;
            if (v2 < 12)
            {
                for (; v6 < 19; v6++)
                {
                    v4 += v11;
                    dunno = v4 - v9;
                    if (dunno > 0)
                        v4 -= (dunno + ((u16)dunno >> 15)) >> 1;
                    v1[v6][v2] = v4 >> 8;
                    if (v1[v6][v2] > 0x1f)
                        v1[v6][v2] = 0x1f;
                }
            }
            else
            {
                for (; v6 < 19; v6++)
                {
                    v4 += v11;
                    v1[v6][v2] = v4 >> 8;
                    if (v1[v6][v2] > 0x1f)
                        v1[v6][v2] = 0x1f;
                }
            }
        }
    }
}

// When the weather is changing, it gradually updates the palettes
// towards the desired gamma shift.
/*static*/ void UpdateWeatherGammaShift(void)
{
    if (gWeather.palProcessingState != WEATHER_PAL_STATE_SCREEN_FADING_OUT)
    {
        if (gWeather.gammaIndex == gWeather.gammaTargetIndex)
        {
            gWeather.palProcessingState = WEATHER_PAL_STATE_IDLE;
        }
        else
        {
            if (++gWeather.gammaStepFrameCounter >= gWeather.gammaStepDelay)
            {
                gWeather.gammaStepFrameCounter = 0;
                if (gWeather.gammaIndex < gWeather.gammaTargetIndex)
                    gWeather.gammaIndex++;
                else
                    gWeather.gammaIndex--;

                ApplyGammaShift(0, 32, gWeather.gammaIndex);
            }
        }
    }
}

/*static*/ void FadeInScreenWithWeather(void)
{
    if (++gWeather.unknown_6CB > 1)
        gWeather.unknown_6CA = 0;

    switch (gWeather.currWeather)
    {
    case WEATHER_RAIN_LIGHT:
    case WEATHER_RAIN_MED:
    case WEATHER_RAIN_HEAVY:
    case WEATHER_SNOW:
    case WEATHER_SHADE:
        if (FadeInScreen_RainShowShade() == FALSE)
        {
            gWeather.gammaIndex = 3;
            gWeather.palProcessingState = WEATHER_PAL_STATE_IDLE;
        }
        break;
    case WEATHER_DROUGHT:
        if (FadeInScreen_Drought() == FALSE)
        {
            gWeather.gammaIndex = -6;
            gWeather.palProcessingState = WEATHER_PAL_STATE_IDLE;
        }
        break;
    case WEATHER_FOG_1:
        if (FadeInScreen_Fog1() == FALSE)
        {
            gWeather.gammaIndex = 0;
            gWeather.palProcessingState = WEATHER_PAL_STATE_IDLE;
        }
        break;
    case WEATHER_ASH:
    case WEATHER_SANDSTORM:
    case WEATHER_FOG_2:
    case WEATHER_FOG_3:
    default:
        if (!gPaletteFade.active)
        {
            gWeather.gammaIndex = gWeather.gammaTargetIndex;
            gWeather.palProcessingState = WEATHER_PAL_STATE_IDLE;
        }
        break;
    }
}

bool8 FadeInScreen_RainShowShade(void)
{
    if (gWeather.fadeScreenCounter == 16)
        return FALSE;

    if (++gWeather.fadeScreenCounter >= 16)
    {
        ApplyGammaShift(0, 32, 3);
        gWeather.fadeScreenCounter = 16;
        return FALSE;
    }

    ApplyGammaShiftWithBlend(0, 32, 3, 16 - gWeather.fadeScreenCounter, gWeather.fadeDestColor);
    return TRUE;
}

bool8 FadeInScreen_Drought(void)
{
    if (gWeather.fadeScreenCounter == 16)
        return FALSE;

    if (++gWeather.fadeScreenCounter >= 16)
    {
        ApplyGammaShift(0, 32, -6);
        gWeather.fadeScreenCounter = 16;
        return FALSE;
    }

    ApplyDroughtGammaShiftWithBlend(-6, 16 - gWeather.fadeScreenCounter, gWeather.fadeDestColor);
    return TRUE;
}

bool8 FadeInScreen_Fog1(void)
{
    if (gWeather.fadeScreenCounter == 16)
        return FALSE;

    gWeather.fadeScreenCounter++;
    ApplyFogBlend(16 - gWeather.fadeScreenCounter, gWeather.fadeDestColor);
    return TRUE;
}

/*static*/ void DoNothing(void)
{ }

/*static*/ void ApplyGammaShift(u8 startPalIndex, u8 numPalettes, s8 gammaIndex)
{
    u16 curPalIndex;
    u16 palOffset;
    u8 *gammaTable;
    u16 i;

    if (gammaIndex > 0)
    {
        gammaIndex--;
        palOffset = startPalIndex * 16;
        numPalettes += startPalIndex;
        curPalIndex = startPalIndex;

        // Loop through the speficied palette range and apply necessary gamma shifts to the colors.
        while (curPalIndex < numPalettes)
        {
            if (sPaletteGammaTypes[curPalIndex] == GAMMA_NONE)
            {
                // No palette change.
                CpuFastCopy(gPlttBufferUnfaded + palOffset, gPlttBufferFaded + palOffset, 16 * sizeof(u16));
                palOffset += 16;
            }
            else
            {
                u8 r, g, b;

                if (sPaletteGammaTypes[curPalIndex] == GAMMA_ALT || curPalIndex - 16 == gWeather.altGammaSpritePalIndex)
                    gammaTable = gWeather.altGammaShifts[gammaIndex];
                else
                    gammaTable = gWeather.gammaShifts[gammaIndex];

                for (i = 0; i < 16; i++)
                {
                    // Apply gamma shift to the original color.
                    struct RGBColor baseColor = *(struct RGBColor *)&gPlttBufferUnfaded[palOffset];
                    r = gammaTable[baseColor.r];
                    g = gammaTable[baseColor.g];
                    b = gammaTable[baseColor.b];
                    gPlttBufferFaded[palOffset++] = (b << 10) | (g << 5) | r;
                }
            }

            curPalIndex++;
        }
    }
    else if (gammaIndex < 0)
    {
        // A negative gammIndex value means that the blending will come from the special Drought weather's palette tables.
        gammaIndex = -gammaIndex - 1;
        palOffset = startPalIndex * 16;
        numPalettes += startPalIndex;
        curPalIndex = startPalIndex;

        while (curPalIndex < numPalettes)
        {
            if (sPaletteGammaTypes[curPalIndex] == GAMMA_NONE)
            {
                // No palette change.
                CpuFastCopy(gPlttBufferUnfaded + palOffset, gPlttBufferFaded + palOffset, 16 * sizeof(u16));
                palOffset += 16;
            }
            else
            {
                for (i = 0; i < 16; i++)
                {
                    gPlttBufferFaded[palOffset] = gUnknown_0854014C[gammaIndex][MACRO1(gPlttBufferUnfaded[palOffset])];
                    palOffset++;
                }
            }

            curPalIndex++;
        }
    }
    else
    {
        // No palette blending.
        CpuFastCopy(gPlttBufferUnfaded + startPalIndex * 16, gPlttBufferFaded + startPalIndex * 16, numPalettes * 16 * sizeof(u16));
    }
}

/*static*/ void ApplyGammaShiftWithBlend(u8 startPalIndex, u8 numPalettes, s8 gammaIndex, u8 blendCoeff, u16 blendColor)
{
    u16 palOffset;
    u16 curPalIndex;
    u16 i;
    struct RGBColor color = *(struct RGBColor *)&blendColor;
    u8 rBlend = color.r;
    u8 gBlend = color.g;
    u8 bBlend = color.b;

    palOffset = startPalIndex * 16;
    numPalettes += startPalIndex;
    gammaIndex--;
    curPalIndex = startPalIndex;

    while (curPalIndex < numPalettes)
    {
        if (sPaletteGammaTypes[curPalIndex] == GAMMA_NONE)
        {
            // No gamma shift. Simply blend the colors.
            BlendPalette(palOffset, 16, blendCoeff, blendColor);
            palOffset += 16;
        }
        else
        {
            u8 *gammaTable;

            if (sPaletteGammaTypes[curPalIndex] == GAMMA_NORMAL)
                gammaTable = gWeather.gammaShifts[gammaIndex];
            else
                gammaTable = gWeather.altGammaShifts[gammaIndex];

            for (i = 0; i < 16; i++)
            {
                struct RGBColor baseColor = *(struct RGBColor *)&gPlttBufferUnfaded[palOffset];
                u8 r = gammaTable[baseColor.r];
                u8 g = gammaTable[baseColor.g];
                u8 b = gammaTable[baseColor.b];

                // Apply gamma shift and target blend color to the original color.
                r += ((rBlend - r) * blendCoeff) >> 4;
                g += ((gBlend - g) * blendCoeff) >> 4;
                b += ((bBlend - b) * blendCoeff) >> 4;
                gPlttBufferFaded[palOffset++] = (b << 10) | (g << 5) | r;
            }
        }

        curPalIndex++;
    }
}

void ApplyDroughtGammaShiftWithBlend(s8 gammaIndex, u8 blendCoeff, u16 blendColor)
{
    struct RGBColor color;
    u8 rBlend;
    u8 gBlend;
    u8 bBlend;
    u16 curPalIndex;
    u16 palOffset;
    u16 i;

    gammaIndex = -gammaIndex - 1;
    color = *(struct RGBColor *)&blendColor;
    rBlend = color.r;
    gBlend = color.g;
    bBlend = color.b;
    palOffset = 0;
    for (curPalIndex = 0; curPalIndex < 32; curPalIndex++)
    {
        if (sPaletteGammaTypes[curPalIndex] == GAMMA_NONE)
        {
            // No gamma shift. Simply blend the colors.
            BlendPalette(palOffset, 16, blendCoeff, blendColor);
            palOffset += 16;
        }
        else
        {
            for (i = 0; i < 16; i++)
            {
                u32 offset;
                struct RGBColor color1;
                struct RGBColor color2;
                u8 r1, g1, b1;
                u8 r2, g2, b2;

                color1 = *(struct RGBColor *)&gPlttBufferUnfaded[palOffset];
                r1 = color1.r;
                g1 = color1.g;
                b1 = color1.b;

                offset = ((b1 & 0x1E) << 7) | ((g1 & 0x1E) << 3) | ((r1 & 0x1E) >> 1);
                color2 = *(struct RGBColor *)&gUnknown_0854014C[gammaIndex][offset];
                r2 = color2.r;
                g2 = color2.g;
                b2 = color2.b;

                r2 += ((rBlend - r2) * blendCoeff) >> 4;
                g2 += ((gBlend - g2) * blendCoeff) >> 4;
                b2 += ((bBlend - b2) * blendCoeff) >> 4;

                gPlttBufferFaded[palOffset++] = (b2 << 10) | (g2 << 5) | r2;
            }
        }
    }
}

void ApplyFogBlend(u8 blendCoeff, u16 blendColor)
{
    struct RGBColor color;
    u8 rBlend;
    u8 gBlend;
    u8 bBlend;
    u16 curPalIndex;

    BlendPalette(0, 256, blendCoeff, blendColor);
    color = *(struct RGBColor *)&blendColor;
    rBlend = color.r;
    gBlend = color.g;
    bBlend = color.b;

    for (curPalIndex = 16; curPalIndex < 32; curPalIndex++)
    {
        if (LightenSpritePaletteInFog(curPalIndex))
        {
            u16 palEnd = (curPalIndex + 1) * 16;
            u16 palOffset = curPalIndex * 16;

            while (palOffset < palEnd)
            {
                struct RGBColor color = *(struct RGBColor *)&gPlttBufferUnfaded[palOffset];
                u8 r = color.r;
                u8 g = color.g;
                u8 b = color.b;

                r += ((28 - r) * 3) >> 2;
                g += ((31 - g) * 3) >> 2;
                b += ((28 - b) * 3) >> 2;

                r += ((rBlend - r) * blendCoeff) >> 4;
                g += ((gBlend - g) * blendCoeff) >> 4;
                b += ((bBlend - b) * blendCoeff) >> 4;

                gPlttBufferFaded[palOffset] = (b << 10) | (g << 5) | r;
                palOffset++;
            }
        }
        else
        {
            BlendPalette(curPalIndex * 16, 16, blendCoeff, blendColor);
        }
    }
}

/*static*/ void MarkFogSpritePalToLighten(u8 paletteIndex)
{
    if (gWeather.lightenedFogSpritePalsCount < 6)
    {
        gWeather.lightenedFogSpritePals[gWeather.lightenedFogSpritePalsCount] = paletteIndex;
        gWeather.lightenedFogSpritePalsCount++;
    }
}

/*static*/ bool8 LightenSpritePaletteInFog(u8 paletteIndex)
{
    u16 i;

    for (i = 0; i < gWeather.lightenedFogSpritePalsCount; i++)
    {
        if (gWeather.lightenedFogSpritePals[i] == paletteIndex)
            return TRUE;
    }

    return FALSE;
}

void sub_80ABC48(s8 gammaIndex)
{
    if (gWeather.palProcessingState == WEATHER_PAL_STATE_IDLE)
    {
        ApplyGammaShift(0, 32, gammaIndex);
        gWeather.gammaIndex = gammaIndex;
    }
}

void sub_80ABC7C(u8 gammaIndex, u8 gammaTargetIndex, u8 gammaStepDelay)
{
    if (gWeather.palProcessingState == WEATHER_PAL_STATE_IDLE)
    {
        gWeather.palProcessingState = WEATHER_PAL_STATE_CHANGING_WEATHER;
        gWeather.gammaIndex = gammaIndex;
        gWeather.gammaTargetIndex = gammaTargetIndex;
        gWeather.gammaStepFrameCounter = 0;
        gWeather.gammaStepDelay = gammaStepDelay;
        sub_80ABC48(gammaIndex);
    }
}

void FadeScreen(u8 mode, s8 delay)
{
    u32 fadeColor;
    bool8 fadeOut;
    bool8 useWeatherPal;

    switch (mode)
    {
    case FADE_FROM_BLACK:
        fadeColor = 0;
        fadeOut = FALSE;
        break;
    case FADE_FROM_WHITE:
        fadeColor = 0xFFFF;
        fadeOut = FALSE;
        break;
    case FADE_TO_BLACK:
        fadeColor = 0;
        fadeOut = TRUE;
        break;
    case FADE_TO_WHITE:
        fadeColor = 0xFFFF;
        fadeOut = TRUE;
        break;
    default:
        return;
    }

    switch (gWeather.currWeather)
    {
    case WEATHER_RAIN_LIGHT:
    case WEATHER_RAIN_MED:
    case WEATHER_RAIN_HEAVY:
    case WEATHER_SNOW:
    case WEATHER_FOG_1:
    case WEATHER_SHADE:
    case WEATHER_DROUGHT:
        useWeatherPal = TRUE;
        break;
    default:
        useWeatherPal = FALSE;
        break;
    }

    if (fadeOut)
    {
        if (useWeatherPal)
            CpuFastCopy(gPlttBufferFaded, gPlttBufferUnfaded, 0x400);

        BeginNormalPaletteFade(0xFFFFFFFF, delay, 0, 16, fadeColor);
        gWeather.palProcessingState = WEATHER_PAL_STATE_SCREEN_FADING_OUT;
    }
    else
    {
        gWeather.fadeDestColor = fadeColor;
        if (useWeatherPal)
            gWeather.fadeScreenCounter = 0;
        else
            BeginNormalPaletteFade(0xFFFFFFFF, delay, 16, 0, fadeColor);

        gWeather.palProcessingState = WEATHER_PAL_STATE_SCREEN_FADING_IN;
        gWeather.unknown_6CA = 1;
        gWeather.unknown_6CB = 0;
        Weather_SetBlendCoeffs(gWeather.currBlendEVA, gWeather.currBlendEVB);
        gWeather.readyForInit = TRUE;
    }
}

bool8 IsWeatherNotFadingIn(void)
{
    return (gWeather.palProcessingState != WEATHER_PAL_STATE_SCREEN_FADING_IN);
}

void UpdateSpritePaletteWithWeather(u8 spritePaletteIndex)
{
    u16 paletteIndex = 16 + spritePaletteIndex;
    u16 i;

    switch (gWeather.palProcessingState)
    {
    case WEATHER_PAL_STATE_SCREEN_FADING_IN:
        if (gWeather.unknown_6CA != 0)
        {
            if (gWeather.currWeather == WEATHER_FOG_1)
                MarkFogSpritePalToLighten(paletteIndex);
            paletteIndex *= 16;
            for (i = 0; i < 16; i++)
                gPlttBufferFaded[paletteIndex + i] = gWeather.fadeDestColor;
        }
        break;
    case WEATHER_PAL_STATE_SCREEN_FADING_OUT:
        paletteIndex *= 16;
        CpuFastCopy(gPlttBufferFaded + paletteIndex, gPlttBufferUnfaded + paletteIndex, 32);
        BlendPalette(paletteIndex, 16, gPaletteFade.y, gPaletteFade.blendColor);
        break;
    // WEATHER_PAL_STATE_CHANGING_WEATHER
    // WEATHER_PAL_STATE_CHANGING_IDLE
    default:
        if (gWeather.currWeather != WEATHER_FOG_1)
        {
            ApplyGammaShift(paletteIndex, 1, gWeather.gammaIndex);
        }
        else
        {
            paletteIndex *= 16;
            BlendPalette(paletteIndex, 16, 12, RGB(28, 31, 28));
        }
        break;
    }
}

void ApplyWeatherGammaShiftToPal(u8 paletteIndex)
{
    ApplyGammaShift(paletteIndex, 1, gWeather.gammaIndex);
}

u8 sub_80ABF20(void)
{
    if (gWeather.palProcessingState == WEATHER_PAL_STATE_SCREEN_FADING_IN)
        return gWeather.unknown_6CA;
    else
        return 0;
}

void LoadCustomWeatherSpritePalette(const u16 *palette)
{
    LoadPalette(palette, 0x100 + gWeather.weatherPicSpritePalIndex * 16, 32);
    UpdateSpritePaletteWithWeather(gWeather.weatherPicSpritePalIndex);
}

void LoadDroughtWeatherPalette(u8 *gammaIndexPtr, u8 *a1)
{
    *gammaIndexPtr = 0x20;
    *a1 = 0x20;
}

void ResetDroughtWeatherPaletteLoading(void)
{
    gWeather.loadDroughtPalsIndex = 1;
    gWeather.loadDroughtPalsOffset = 1;
}

bool8 LoadDroughtWeatherPalettes(void)
{
    if (gWeather.loadDroughtPalsIndex < 32)
    {
        LoadDroughtWeatherPalette(&gWeather.loadDroughtPalsIndex, &gWeather.loadDroughtPalsOffset);
        if (gWeather.loadDroughtPalsIndex < 32)
            return TRUE;
    }
    return FALSE;
}

void sub_80ABFE0(s8 gammaIndex)
{
    sub_80ABC48(-gammaIndex - 1);
}

void sub_80ABFF0(void)
{
    gWeather.unknown_73C = 0;
    gWeather.unknown_740 = 0;
    gWeather.unknown_742 = 0;
    gWeather.unknown_73E = 0;
}

void sub_80AC01C(void)
{
    switch (gWeather.unknown_742)
    {
    case 0:
        if (++gWeather.unknown_740 > 5)
        {
            gWeather.unknown_740 = 0;
            sub_80ABFE0(gWeather.unknown_73C++);
            if (gWeather.unknown_73C > 5)
            {
                gWeather.unknown_73E = gWeather.unknown_73C;
                gWeather.unknown_742 = 1;
                gWeather.unknown_740 = 0x3C;
            }
        }
        break;
    case 1:
        gWeather.unknown_740 = (gWeather.unknown_740 + 3) & 0x7F;
        gWeather.unknown_73C = ((gSineTable[gWeather.unknown_740] - 1) >> 6) + 2;
        if (gWeather.unknown_73C != gWeather.unknown_73E)
            sub_80ABFE0(gWeather.unknown_73C);
        gWeather.unknown_73E = gWeather.unknown_73C;
        break;
    case 2:
        if (++gWeather.unknown_740 > 5)
        {
            gWeather.unknown_740 = 0;
            sub_80ABFE0(--gWeather.unknown_73C);
            if (gWeather.unknown_73C == 3)
                gWeather.unknown_742 = 0;
        }
        break;
    }
}

void Weather_SetBlendCoeffs(u8 eva, u8 evb)
{
    gWeather.currBlendEVA = eva;
    gWeather.currBlendEVB = evb;
    gWeather.targetBlendEVA = eva;
    gWeather.targetBlendEVB = evb;
    SetGpuReg(REG_OFFSET_BLDALPHA, BLDALPHA_BLEND(eva, evb));
}

void Weather_SetTargetBlendCoeffs(u8 eva, u8 evb, int delay)
{
    gWeather.targetBlendEVA = eva;
    gWeather.targetBlendEVB = evb;
    gWeather.blendDelay = delay;
    gWeather.blendFrameCounter = 0;
    gWeather.blendUpdateCounter = 0;
}

bool8 Weather_UpdateBlend(void)
{
    if (gWeather.currBlendEVA == gWeather.targetBlendEVA
     && gWeather.currBlendEVB == gWeather.targetBlendEVB)
        return TRUE;

    if (++gWeather.blendFrameCounter > gWeather.blendDelay)
    {
        gWeather.blendFrameCounter = 0;
        gWeather.blendUpdateCounter++;

        // Update currBlendEVA and currBlendEVB on alternate frames
        if (gWeather.blendUpdateCounter & 1)
        {
            if (gWeather.currBlendEVA < gWeather.targetBlendEVA)
                gWeather.currBlendEVA++;
            else if (gWeather.currBlendEVA > gWeather.targetBlendEVA)
                gWeather.currBlendEVA--;
        }
        else
        {
            if (gWeather.currBlendEVB < gWeather.targetBlendEVB)
                gWeather.currBlendEVB++;
            else if (gWeather.currBlendEVB > gWeather.targetBlendEVB)
                gWeather.currBlendEVB--;
        }
    }

    SetGpuReg(REG_OFFSET_BLDALPHA, BLDALPHA_BLEND(gWeather.currBlendEVA, gWeather.currBlendEVB));

    if (gWeather.currBlendEVA == gWeather.targetBlendEVA
     && gWeather.currBlendEVB == gWeather.targetBlendEVB)
        return TRUE;

    return FALSE;
}

void sub_80AC274(u8 a)
{
    switch (a)
    {
    case 1:
        SetWeather(WEATHER_CLOUDS);
        break;
    case 2:
        SetWeather(WEATHER_SUNNY);
        break;
    case 3:
        SetWeather(WEATHER_RAIN_LIGHT);
        break;
    case 4:
        SetWeather(WEATHER_SNOW);
        break;
    case 5:
        SetWeather(WEATHER_RAIN_MED);
        break;
    case 6:
        SetWeather(WEATHER_FOG_1);
        break;
    case 7:
        SetWeather(WEATHER_FOG_2);
        break;
    case 8:
        SetWeather(WEATHER_ASH);
        break;
    case 9:
        SetWeather(WEATHER_SANDSTORM);
        break;
    case 10:
        SetWeather(WEATHER_SHADE);
        break;
    }
}

u8 GetCurrentWeather(void)
{
    return gWeather.currWeather;
}

void SetRainStrengthFromSoundEffect(u16 soundEffect)
{
    if (gWeather.palProcessingState != WEATHER_PAL_STATE_SCREEN_FADING_OUT)
    {
        switch (soundEffect)
        {
        case SE_T_KOAME:
            gWeather.rainStrength = 0;
            break;
        case SE_T_OOAME:
            gWeather.rainStrength = 1;
            break;
        case SE_T_AME:
            gWeather.rainStrength = 2;
            break;
        default:
            return;
        }

        PlaySE(soundEffect);
    }
}

void PlayRainSoundEffect(void)
{
    if (IsSpecialSEPlaying())
    {
        switch (gWeather.rainStrength)
        {
        case 0:
            PlaySE(SE_T_KOAME_E);
            break;
        case 1:
            PlaySE(SE_T_OOAME_E);
            break;
        case 2:
        default:
            PlaySE(SE_T_AME_E);
            break;
        }
    }
}

u8 IsWeatherChangeComplete(void)
{
    return gWeather.weatherChangeComplete;
}

void SetWeatherScreenFadeOut(void)
{
    gWeather.palProcessingState = WEATHER_PAL_STATE_SCREEN_FADING_OUT;
}

void sub_80AC3E4(void)
{
    gWeather.palProcessingState = WEATHER_PAL_STATE_IDLE;
}

void PreservePaletteInWeather(u8 preservedPalIndex)
{
    CpuCopy16(sBasePaletteGammaTypes, gFieldEffectPaletteGammaTypes, 32);
    gFieldEffectPaletteGammaTypes[preservedPalIndex] = GAMMA_NONE;
    sPaletteGammaTypes = gFieldEffectPaletteGammaTypes;
}

void ResetPreservedPalettesInWeather(void)
{
    sPaletteGammaTypes = sBasePaletteGammaTypes;
}