#include "global.h"
#include "event_data.h"
#include "task.h"
#include "field_player_avatar.h"
#include "fieldmap.h"
#include "field_camera.h"
#include "constants/metatile_labels.h"

static EWRAM_DATA u8 sEscalatorTaskId = 0;

static void SetEscalatorMetatile(u8 taskId, const s16 *metatileIds, u16 metatileMasks);
static void Task_DrawEscalator(u8 taskId);
static void Task_DrawTeleporterHousing(u8 taskId);
static void Task_DrawTeleporterCable(u8 taskId);

#define ESCALATOR_STAGES     3
#define LAST_ESCALATOR_STAGE (ESCALATOR_STAGES - 1)

static const u16 sEscalatorMetatiles_BottomNextRail[ESCALATOR_STAGES] = 
{
    METATILE_PokemonCenter_Escalator_BottomNextRail_Transition2, 
    METATILE_PokemonCenter_Escalator_BottomNextRail_Transition1, 
    METATILE_PokemonCenter_Escalator_BottomNextRail_Normal
};

static const u16 sEscalatorMetatiles_BottomRail[ESCALATOR_STAGES] = 
{
    METATILE_PokemonCenter_Escalator_BottomRail_Transition2, 
    METATILE_PokemonCenter_Escalator_BottomRail_Transition1, 
    METATILE_PokemonCenter_Escalator_BottomRail_Normal
};

static const u16 sEscalatorMetatiles_BottomNext[ESCALATOR_STAGES] = 
{
    METATILE_PokemonCenter_Escalator_BottomNext_Transition2, 
    METATILE_PokemonCenter_Escalator_BottomNext_Transition1, 
    METATILE_PokemonCenter_Escalator_BottomNext_Normal
};

static const u16 sEscalatorMetatiles_Bottom[ESCALATOR_STAGES] = 
{
    METATILE_PokemonCenter_Escalator_Bottom_Transition2, 
    METATILE_PokemonCenter_Escalator_Bottom_Transition1, 
    METATILE_PokemonCenter_Escalator_Bottom_Normal
};

static const u16 sEscalatorMetatiles_TopNext[ESCALATOR_STAGES] = 
{
    METATILE_PokemonCenter_Escalator_TopNext_Normal, 
    METATILE_PokemonCenter_Escalator_TopNext_Transition1, 
    METATILE_PokemonCenter_Escalator_TopNext_Transition2
};

static const u16 sEscalatorMetatiles_Top[ESCALATOR_STAGES] = 
{
    METATILE_PokemonCenter_Escalator_Top_Normal, 
    METATILE_PokemonCenter_Escalator_Top_Transition1, 
    METATILE_PokemonCenter_Escalator_Top_Transition2
};

static const u16 sEscalatorMetatiles_TopNextRail[ESCALATOR_STAGES] = 
{
    METATILE_PokemonCenter_Escalator_TopNextRail_Normal, 
    METATILE_PokemonCenter_Escalator_TopNextRail_Transition1, 
    METATILE_PokemonCenter_Escalator_TopNextRail_Transition2
};

#define tState            data[0]
#define tTransitionStage  data[1]
#define tGoingUp          data[2]
#define tDrawingEscalator data[3]
#define tPlayerX          data[4]
#define tPlayerY          data[5]

static void SetEscalatorMetatile(u8 taskId, const s16 *metatileIds, u16 metatileMasks)
{
    s16 x, y, transitionStage;
    s16 i, j;
    
    x = gTasks[taskId].tPlayerX - 1;
    y = gTasks[taskId].tPlayerY - 1;
    transitionStage = gTasks[taskId].tTransitionStage;
    
    // Check all the escalator sections and only progress the selected one to the next stage
    if (!gTasks[taskId].tGoingUp)
    {
        for (i = 0; i < 3; i++)
        {
            for (j = 0; j < 3; j++)
            {
                s32 id = MapGridGetMetatileIdAt(x + j, y + i);
                
                if (metatileIds[transitionStage] == (s16)id)
                {
                    if (transitionStage != LAST_ESCALATOR_STAGE)
                        MapGridSetMetatileIdAt(x + j, y + i, metatileMasks | metatileIds[transitionStage + 1]);
                    else
                        MapGridSetMetatileIdAt(x + j, y + i, metatileMasks | metatileIds[0]);
                }
            }
        }
    }
    else
    {
        for (i = 0; i < 3; i++)
        {
            for (j = 0; j < 3; j++)
            {
                s32 id = MapGridGetMetatileIdAt(x + j, y + i);

                if (metatileIds[LAST_ESCALATOR_STAGE - transitionStage] == (s16)id)
                {
                    if (transitionStage != LAST_ESCALATOR_STAGE)
                        MapGridSetMetatileIdAt(x + j, y + i, metatileMasks | metatileIds[1 - transitionStage]);
                    else
                        MapGridSetMetatileIdAt(x + j, y + i, metatileMasks | metatileIds[LAST_ESCALATOR_STAGE]);
                }
            }
        }
    }
}

static void Task_DrawEscalator(u8 taskId)
{
    s16 *data = gTasks[taskId].data;
    u16 state;
    
    tDrawingEscalator = TRUE;

    // Set tile for each section of the escalator in sequence for current transition stage
    switch (tState)
    {
    case 0:
        SetEscalatorMetatile(taskId, sEscalatorMetatiles_BottomNextRail, 0);
        break;
    case 1:
        SetEscalatorMetatile(taskId, sEscalatorMetatiles_BottomRail, 0);
        break;
    case 2:
        SetEscalatorMetatile(taskId, sEscalatorMetatiles_BottomNext, METATILE_COLLISION_MASK);
        break;
    case 3:
        SetEscalatorMetatile(taskId, sEscalatorMetatiles_Bottom, 0);
        break;
    case 4:
        SetEscalatorMetatile(taskId, sEscalatorMetatiles_TopNext, METATILE_COLLISION_MASK);
        break;
    case 5:
        SetEscalatorMetatile(taskId, sEscalatorMetatiles_Top, 0);
        break;
    case 6:
        SetEscalatorMetatile(taskId, sEscalatorMetatiles_TopNextRail, 0);
    default:
        break;
    }
    
    tState = (tState + 1) & 7;
    state = tState & 7;

    // If all sections of the escalator have been set, draw map and progress to next stage
    if (state == 0)
    {
        DrawWholeMapView();
        tTransitionStage = (tTransitionStage + 1) % ESCALATOR_STAGES;
        tDrawingEscalator = FALSE;
    }
}

static u8 CreateEscalatorTask(bool16 goingUp)
{
    u8 taskId;
    s16 *data;

    taskId = CreateTask(Task_DrawEscalator, 0);
    data = gTasks[taskId].data;
    PlayerGetDestCoords(&tPlayerX, &tPlayerY);
    tState = 0;
    tTransitionStage = 0;
    tGoingUp = goingUp;
    Task_DrawEscalator(taskId);
    return taskId;
}

void StartEscalator(bool8 goingUp)
{
    u8 taskId;
    
    taskId = CreateEscalatorTask(goingUp);
    sEscalatorTaskId = taskId;
}

void StopEscalator(void)
{
    DestroyTask(sEscalatorTaskId);
}

bool8 IsEscalatorMoving(void)
{    
    if (gTasks[sEscalatorTaskId].tDrawingEscalator == FALSE)
    {
        if (gTasks[sEscalatorTaskId].tTransitionStage != LAST_ESCALATOR_STAGE)
            return TRUE;
        return FALSE;
    }
    else
    {
        return TRUE;
    }
}

#undef tState
#undef tTransitionStage
#undef tGoingUp
#undef tDrawingEscalator
#undef tPlayerX
#undef tPlayerY

#define tTimer data[0]
#define tState data[1]
#define tX     data[2]
#define tY     data[3]

void AnimateTeleporterHousing(void)
{
    u8 taskId;
    s16 *data;
    
    taskId = CreateTask(Task_DrawTeleporterHousing, 0);
    gTasks[taskId].tTimer = 0;
    gTasks[taskId].tState = 0;
    data = gTasks[taskId].data;
    PlayerGetDestCoords(&tX, &tY);

    // Set the coords of whichever teleporter is being animated
    // 0 for the right teleporter, 1 for the left teleporter
    if (gSpecialVar_0x8004 == 0)
    {
        gTasks[taskId].tX += 6;
        gTasks[taskId].tY -= 5;
    }
    else
    {
        gTasks[taskId].tX -= 1;
        gTasks[taskId].tY -= 5;
    }    
}

static void Task_DrawTeleporterHousing(u8 taskId)
{
    s16 *data = gTasks[taskId].data;
    
    if (tTimer == 0)
    {
        // Alternate the teleporter light / brightness of the teleporter door
        if ((tState & 1) == 0)
        {
            MapGridSetMetatileIdAt(tX, tY, METATILE_SeaCottage_Teleporter_Light_Yellow | METATILE_COLLISION_MASK);
            MapGridSetMetatileIdAt(tX, tY + 2, METATILE_SeaCottage_Teleporter_Door_HalfGlowing | METATILE_COLLISION_MASK);
        }
        else
        {
            MapGridSetMetatileIdAt(tX, tY, METATILE_SeaCottage_Teleporter_Light_Red | METATILE_COLLISION_MASK);
            MapGridSetMetatileIdAt(tX, tY + 2, METATILE_SeaCottage_Teleporter_Door_FullGlowing | METATILE_COLLISION_MASK);
        }
        CurrentMapDrawMetatileAt(tX, tY);
        CurrentMapDrawMetatileAt(tX, tY + 2);
    }
    
    tTimer++;
    if (tTimer != 16)
        return;
    
    tTimer = 0;
    tState++;
    if (tState != 13)
        return;
    
    MapGridSetMetatileIdAt(tX, tY, METATILE_SeaCottage_Teleporter_Light_Green | METATILE_COLLISION_MASK);
    MapGridSetMetatileIdAt(tX, tY + 2, METATILE_SeaCottage_Teleporter_Door | METATILE_COLLISION_MASK);
    CurrentMapDrawMetatileAt(tX, tY);
    CurrentMapDrawMetatileAt(tX, tY + 2);
    DestroyTask(taskId);
}

void AnimateTeleporterCable(void)
{
    u8 taskId;
    s16 *data;
    
    taskId = CreateTask(Task_DrawTeleporterCable, 0);
    gTasks[taskId].tTimer = 0;
    gTasks[taskId].tState = 0;
    data = gTasks[taskId].data;
    PlayerGetDestCoords(&tX, &tY);
    gTasks[taskId].tX += 4;
    gTasks[taskId].tY -= 5;
}

static void Task_DrawTeleporterCable(u8 taskId)
{
    s16 *data = gTasks[taskId].data;
    
    if (tTimer == 0)
    {
        if (tState != 0)
        {
            // Set default cable tiles to clear the ball
            MapGridSetMetatileIdAt(tX, tY, METATILE_SeaCottage_Teleporter_Cable_Top | METATILE_COLLISION_MASK);
            MapGridSetMetatileIdAt(tX, tY + 1, METATILE_SeaCottage_Teleporter_Cable_Bottom | METATILE_COLLISION_MASK);
            CurrentMapDrawMetatileAt(tX, tY);
            CurrentMapDrawMetatileAt(tX, tY + 1);

            // End after drawing 4 times (length of the cable)
            if (tState == 4)
            {
                DestroyTask(taskId);
                return;
            }
            
            tX--;
        }

        // Draw the cable ball
        MapGridSetMetatileIdAt(tX, tY, METATILE_SeaCottage_Teleporter_CableBall_Top | METATILE_COLLISION_MASK);
        MapGridSetMetatileIdAt(tX, tY + 1, METATILE_SeaCottage_Teleporter_CableBall_Bottom | METATILE_COLLISION_MASK);
        CurrentMapDrawMetatileAt(tX, tY);
        CurrentMapDrawMetatileAt(tX, tY + 1);
    }
    
    tTimer++;
    if (tTimer == 4)
    {
        tTimer = 0;
        tState++;
    }
}

#undef tTimer
#undef tState
#undef tX
#undef tY