#define NENT_DEPRECATED
#include "asm.h"
#include "entity.h"
#include "functions.h"
#include "player.h"
#include "room.h"

extern Entity* gUnk_020000B0;
extern Entity* (*const gUnk_080D3BE8[])(void);

extern void ReplaceMonitoredEntity(Entity*, Entity*);

Entity* sub_08049DF4(u32 arg0) {
    if (gUnk_020000B0 != NULL) {
        return gUnk_020000B0;
    }
    return gUnk_080D3BE8[arg0]();
}

Entity* sub_08049E18(void) {
    if ((gPlayerState.field_0x3c[0] == 0) && !(gPlayerState.flags & 0x22189b75)) {
        gUnk_020000B0 = &gPlayerEntity;
        return &gPlayerEntity;
    }
    return NULL;
}

Entity* sub_08049E4C(void) {
    if ((gPlayerState.field_0x3c[0] == 0) && !(gPlayerState.flags & 0x22189bf5)) {
        gUnk_020000B0 = &gPlayerEntity;
        return &gPlayerEntity;
    }
    return NULL;
}

Entity* sub_08049E80(void) {
    if ((gPlayerState.field_0x3c[0] != 0) || !(gPlayerState.flags & 0x80)) {
        return NULL;
    }
    gUnk_020000B0 = &gPlayerEntity;
    return &gPlayerEntity;
}

Entity* sub_08049EB0(void) {
    if ((gPlayerState.field_0x3c[0] == 0) && !(gPlayerState.flags & 0x80190)) {
        gUnk_020000B0 = &gPlayerEntity;
        return &gPlayerEntity;
    }
    return NULL;
}

u32 sub_08049EE4(Entity* ent) {
    GenericEntity* genEnt = (GenericEntity*)ent;

    u16 tempLO = genEnt->field_0x70.HALF.LO + 4 * genEnt->field_0x6e.HALF.LO;
    u16 tempHI = genEnt->field_0x70.HALF.HI + 4 * genEnt->field_0x6e.HALF.HI;

    return CalculateDirectionTo(genEnt->base.x.HALF.HI, genEnt->base.y.HALF.HI, tempLO, tempHI);
}

bool32 sub_08049F1C(Entity* entA, Entity* entB, s32 maxDist) {
    if ((entA->collisionLayer & entB->collisionLayer) != 0) {
        s32 xDiff = entB->x.HALF.HI - entA->x.HALF.HI;
        s32 yDiff = entB->y.HALF.HI - entA->y.HALF.HI;
        s32 maxDistSq = maxDist * maxDist;
        s32 distSq = xDiff * xDiff + yDiff * yDiff;

        if (maxDistSq >= distSq) {
            return TRUE;
        }
    }
    return FALSE;
}

bool32 PlayerInRange(Entity* ent, u32 arg1, s32 maxDist) {
    Entity* tempEnt = sub_08049DF4(arg1);
    if (tempEnt == NULL) {
        return FALSE;
    } else {
        return sub_08049F1C(ent, tempEnt, maxDist);
    }
}

u32 sub_08049F84(Entity* ent, s32 arg2) {
    Entity* target = sub_08049DF4(arg2);

    if (target == NULL) {
        return 0xFF;
    } else {
        return GetFacingDirection(ent, target);
    }
}

bool32 sub_08049FA0(Entity* ent) {
    GenericEntity* genEnt = (GenericEntity*)ent;
    u32 temp = 8 * genEnt->field_0x6e.HALF.LO;

    if (temp >= genEnt->base.x.HALF.HI - genEnt->field_0x70.HALF_U.LO) {
        temp = 8 * genEnt->field_0x6e.HALF.HI;
        if (temp >= genEnt->base.y.HALF.HI - genEnt->field_0x70.HALF_U.HI) {
            return TRUE;
        }
    }
    return FALSE;
}

bool32 sub_08049FDC(Entity* ent, u32 arg1) {
    u32 temp;
    GenericEntity* genEnt = (GenericEntity*)ent;
    GenericEntity* tempEnt = (GenericEntity*)sub_08049DF4(arg1);

    if (tempEnt != NULL) {
        temp = 8 * genEnt->field_0x6e.HALF.LO;
        if (temp >= tempEnt->base.x.HALF.HI - genEnt->field_0x70.HALF_U.LO) {
            temp = 8 * genEnt->field_0x6e.HALF.HI;
            if (temp >= tempEnt->base.y.HALF.HI - genEnt->field_0x70.HALF_U.HI) {
                return TRUE;
            }
        }
    }
    return FALSE;
}

u32 sub_0804A024(Entity* ent, u32 arg1, u32 arg2) {
    Entity* tempEnt = sub_08049DF4(arg1);
    if (tempEnt == NULL) {
        return 0xFF;
    } else {
        return sub_0804A044(ent, tempEnt, arg2);
    }
}

u32 sub_0804A168(Entity*, Entity*, LayerStruct*);
u32 sub_0804A318(Entity*, Entity*, LayerStruct*);

u32 sub_0804A044(Entity* entA, Entity* entB, u32 arg2) {
    LayerStruct* layer;
    s32 ret;
    s32 yDiff;
    s32 xDiff;
    s32 flags;

    if ((entB->collisionLayer & entA->collisionLayer) != 0) {
        flags = 0;
        xDiff = entB->x.HALF.HI + entB->hitbox->offset_x - entA->x.HALF.HI - entA->hitbox->offset_x;

        if (arg2 >= xDiff + (arg2 >> 1)) {
            flags |= 1;
        }
        if (arg2 << 1 >= xDiff + arg2) {
            flags |= 2;
        }

        yDiff = entB->y.HALF.HI + entB->hitbox->offset_y - entA->y.HALF.HI - entA->hitbox->offset_y;
        if (arg2 >= yDiff + (arg2 >> 1)) {
            flags |= 4;
        }
        if (arg2 << 1 >= yDiff + arg2) {
            flags |= 8;
        }

        if (flags && ((flags & 5) != 0xA)) {
            layer = GetLayerByIndex(entA->collisionLayer);
            if (xDiff < 0) {
                xDiff = -xDiff;
            }
            if (yDiff < 0) {
                yDiff = -yDiff;
            }
            if (xDiff < yDiff) {
                if (flags & 1) {
                    ret = sub_0804A168(entA, entB, layer);
                    if (ret != 0xFF) {
                        return ret;
                    }
                }
                if (!(flags & 4)) {
                    return 0xFF;
                }
                ret = sub_0804A318(entA, entB, layer);
            } else {
                if (flags & 4) {
                    ret = sub_0804A318(entA, entB, layer);
                    if (ret != 0xFF) {
                        return ret;
                    }
                }
                if (!(flags & 1)) {
                    return 0xFF;
                }
                ret = sub_0804A168(entA, entB, layer);
            }
            if (ret != 0xFF) {
                return ret;
            }
        }
    }
    return 0xFF;
}

bool32 sub_0804A4BC(u8* arg0, u8* arg1, s32 arg2, u32 arg3);

u32 sub_0804A168(Entity* entA, Entity* entB, LayerStruct* layer) {
    u32 uVar2;
    u32 uVar3;
    u32 tile1;
    u32 tile2;

    if (entB->y.HALF.HI > entA->y.HALF.HI) {
        uVar2 = entA->x.HALF.HI - 4;
        uVar3 = ((uVar2 & 0xF) < 8) ? 10 : 5;
        tile1 = TILE(uVar2, entA->y.HALF.HI + 10);
        tile2 = TILE(uVar2, entB->y.HALF.HI);

        if (sub_0804A4BC(layer->collisionData + tile1, layer->collisionData + tile2, 0x40, uVar3)) {
            uVar2 = entA->x.HALF.HI + 4;
            uVar3 ^= 0xF;
            tile1 = TILE(uVar2, entA->y.HALF.HI + 10);
            tile2 = TILE(uVar2, entB->y.HALF.HI);

            if (sub_0804A4BC(layer->collisionData + tile1, layer->collisionData + tile2, 0x40, uVar3)) {
                return 0x10;
            }
        }
    } else {
        uVar2 = entA->x.HALF.HI - 4;
        uVar3 = ((uVar2 & 0xF) < 8) ? 10 : 5;
        tile1 = TILE(uVar2, entA->y.HALF.HI - 10);
        tile2 = TILE(uVar2, entB->y.HALF.HI);

        if (sub_0804A4BC(layer->collisionData + tile1, layer->collisionData + tile2, -0x40, uVar3)) {
            uVar2 = entA->x.HALF.HI + 4;
            uVar3 ^= 0xF;
            tile1 = TILE(uVar2, entA->y.HALF.HI - 10);
            tile2 = TILE(uVar2, entB->y.HALF.HI);

            if (sub_0804A4BC(layer->collisionData + tile1, layer->collisionData + tile2, -0x40, uVar3)) {
                return 0;
            }
        }
    }
    return 0xFF;
}

u32 sub_0804A318(Entity* entA, Entity* entB, LayerStruct* layer) {
    u32 uVar2;
    u32 uVar3;
    u32 tile1;
    u32 tile2;

    if (entB->x.HALF.HI > entA->x.HALF.HI) {
        uVar2 = entA->y.HALF.HI - 4;
        uVar3 = ((uVar2 & 0xF) < 8) ? 0xC : 3;
        tile1 = TILE(entA->x.HALF.HI + 10, uVar2);
        tile2 = TILE(entB->x.HALF.HI, uVar2);

        if (sub_0804A4BC(layer->collisionData + tile1, layer->collisionData + tile2, 1, uVar3)) {
            uVar2 = entA->y.HALF.HI + 4;
            uVar3 ^= 0xF;
            tile1 = TILE(entA->x.HALF.HI + 10, uVar2);
            tile2 = TILE(entB->x.HALF.HI, uVar2);

            if (sub_0804A4BC(layer->collisionData + tile1, layer->collisionData + tile2, 1, uVar3)) {
                return 8;
            }
        }
    } else {
        uVar2 = entA->y.HALF.HI - 4;
        uVar3 = ((uVar2 & 0xF) < 8) ? 0xC : 3;
        tile1 = TILE(entA->x.HALF.HI - 10, uVar2);
        tile2 = TILE(entB->x.HALF.HI, uVar2);

        if (sub_0804A4BC(layer->collisionData + tile1, layer->collisionData + tile2, -1, uVar3)) {
            uVar2 = entA->y.HALF.HI + 4;
            uVar3 ^= 0xF;
            tile1 = TILE(entA->x.HALF.HI - 10, uVar2);
            tile2 = TILE(entB->x.HALF.HI, uVar2);
            if (sub_0804A4BC(layer->collisionData + tile1, layer->collisionData + tile2, -1, uVar3)) {
                return 0x18;
            }
        }
    }
    return 0xFF;
}

bool32 sub_0804A4BC(u8* arg0, u8* arg1, s32 arg2, u32 arg3) {
    while (arg0 != arg1) {
        u8 r0 = *arg0;

        if (r0 != 0) {
            if (r0 > 0xF) {
                return FALSE;
            }

            r0 &= arg3;
            if (r0 != 0) {
                return FALSE;
            }
        }
        arg0 += arg2;
    }

    return TRUE;
}

void sub_0804A4E4(Entity* entA, Entity* entB) {
    GenericEntity* r5 = (GenericEntity*)entA;
    GenericEntity* r6 = (GenericEntity*)entB;

    r6->field_0x6c.HALF.HI = (r5->field_0x6c.HALF.HI & 0x40) | 4;
    r6->field_0x6c.HALF.LO = r5->field_0x6c.HALF.LO;
    r6->field_0x70.HALF.LO = r5->field_0x70.HALF.LO;
    r6->field_0x70.HALF.HI = r5->field_0x70.HALF.HI;
    r6->field_0x6e.HALF.LO = r5->field_0x6e.HALF.LO;
    r6->field_0x6e.HALF.HI = r5->field_0x6e.HALF.HI;

    CopyPositionAndSpriteOffset(&r5->base, &r6->base);

    if (r5->field_0x6c.HALF.HI & 0x40) {
        ReplaceMonitoredEntity(&r5->base, &r6->base);
    }
}