(*
 * Hedgewars, a free turn based strategy game
 * Copyright (c) 2004-2012 Andrey Korotaev <unC0Rr@gmail.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2 of the License
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
 *)

{$INCLUDE "options.inc"}

unit uAIMisc;
interface
uses SDLh, uConsts, uFloat, uTypes;

const MAXBONUS = 1024;

      afTrackFall  = $00000001;
      afErasesLand = $00000002;
      afSetSkip    = $00000004;


type TTarget = record
    Point: TPoint;
    Score: LongInt;
    skip: boolean;
    end;
TTargets = record
    Count: Longword;
    ar: array[0..Pred(cMaxHHs)] of TTarget;
    end;
TJumpType = (jmpNone, jmpHJump, jmpLJump);
TGoInfo = record
    Ticks: Longword;
    FallPix: Longword;
    JumpType: TJumpType;
    end;
TBonus = record
    X, Y: LongInt;
    Radius: LongInt;
    Score: LongInt;
    end;

procedure initModule;
procedure freeModule;

procedure FillTargets;
procedure FillBonuses(isAfterAttack: boolean);
procedure AwareOfExplosion(x, y, r: LongInt); inline;

function  RatePlace(Gear: PGear): LongInt;
function  TestColl(x, y, r: LongInt): boolean; inline;
function  TestCollExcludingObjects(x, y, r: LongInt): boolean; inline;
function  TestCollExcludingMe(Me: PGear; x, y, r: LongInt): boolean; inline;
function  TraceShoveFall(x, y, dX, dY: Real): LongInt;

function  RateExplosion(Me: PGear; x, y, r: LongInt): LongInt; inline;
function  RateExplosion(Me: PGear; x, y, r: LongInt; Flags: LongWord): LongInt;
function  RateShove(Me: PGear; x, y, r, power, kick: LongInt; gdX, gdY: real; Flags: LongWord): LongInt;
function  RateShotgun(Me: PGear; gdX, gdY: real; x, y: LongInt): LongInt;
function  RateHammer(Me: PGear): LongInt;

function  HHGo(Gear, AltGear: PGear; var GoInfo: TGoInfo): boolean;
function  AIrndSign(num: LongInt): LongInt;

var ThinkingHH: PGear;
    Targets: TTargets;

    bonuses: record
        Count: Longword;
        ar: array[0..Pred(MAXBONUS)] of TBonus;
        end;

implementation
uses uCollisions, uVariables, uUtils, uDebug, uLandTexture;

const KillScore = 200;

var friendlyfactor: LongInt = 300;
    KnownExplosion: record
        X, Y, Radius: LongInt
        end = (X: 0; Y: 0; Radius: 0);

procedure FillTargets;
var i, t: Longword;
    f, e: LongInt;
begin
Targets.Count:= 0;
f:= 0;
e:= 0;
for t:= 0 to Pred(TeamsCount) do
    with TeamsArray[t]^ do
        if not hasGone then
            begin
            for i:= 0 to cMaxHHIndex do
                if (Hedgehogs[i].Gear <> nil)
                and (Hedgehogs[i].Gear <> ThinkingHH) then
                    begin
                    with Targets.ar[Targets.Count], Hedgehogs[i] do
                        begin
                        skip:= false;
                        Point.X:= hwRound(Gear^.X);
                        Point.Y:= hwRound(Gear^.Y);
                        if Clan <> CurrentTeam^.Clan then
                            begin
                            Score:=  Gear^.Health;
                            inc(e)
                            end else
                            begin
                            Score:= -Gear^.Health;
                            inc(f)
                            end
                        end;
                    inc(Targets.Count)
                    end;
            end;

if e > f then friendlyfactor:= 300 + (e - f) * 30
else friendlyfactor:= max(30, 300 - f * 80 div max(1,e))
end;

procedure AddBonus(x, y: LongInt; r: Longword; s: LongInt); inline;
begin
if(bonuses.Count < MAXBONUS) then
    begin
    bonuses.ar[bonuses.Count].x:= x;
    bonuses.ar[bonuses.Count].y:= y;
    bonuses.ar[bonuses.Count].Radius:= r;
    bonuses.ar[bonuses.Count].Score:= s;
    inc(bonuses.Count);
    end;
end;

procedure FillBonuses(isAfterAttack: boolean);
var Gear: PGear;
    MyClan: PClan;
begin
bonuses.Count:= 0;
MyClan:= ThinkingHH^.Hedgehog^.Team^.Clan;
Gear:= GearsList;
while Gear <> nil do
    begin
        case Gear^.Kind of
            gtCase:
            AddBonus(hwRound(Gear^.X), hwRound(Gear^.Y), 33, 25);
            gtFlame:
                if (Gear^.State and gsttmpFlag) <> 0 then
                    AddBonus(hwRound(Gear^.X), hwRound(Gear^.Y), 20, -50);
// avoid mines unless they are very likely to be duds, or are duds. also avoid if they are about to blow 
            gtMine:
                if ((Gear^.State and gstAttacking) = 0) and (((cMineDudPercent < 90) and (Gear^.Health <> 0))
                or (isAfterAttack and (Gear^.Health = 0) and (Gear^.Damage > 30))) then
                    AddBonus(hwRound(Gear^.X), hwRound(Gear^.Y), 50, -50)
                else if (Gear^.State and gstAttacking) <> 0 then
                    AddBonus(hwRound(Gear^.X), hwRound(Gear^.Y), 100, -50); // mine is on
                    
            gtExplosives:
            if isAfterAttack then
                AddBonus(hwRound(Gear^.X), hwRound(Gear^.Y), 75, -60 + Gear^.Health);
                
            gtSMine:
                AddBonus(hwRound(Gear^.X), hwRound(Gear^.Y), 50, -30);
                
            gtDynamite:
                AddBonus(hwRound(Gear^.X), hwRound(Gear^.Y), 150, -75);
                
            gtHedgehog:
                begin
                if Gear^.Damage >= Gear^.Health then
                    AddBonus(hwRound(Gear^.X), hwRound(Gear^.Y), 60, -25)
                else
                    if isAfterAttack and (ThinkingHH^.Hedgehog <> Gear^.Hedgehog) then
                        if (ClansCount > 2) or (MyClan = Gear^.Hedgehog^.Team^.Clan) then
                            AddBonus(hwRound(Gear^.X), hwRound(Gear^.Y), 150, -3) // hedgehog-friend
                        else
                            AddBonus(hwRound(Gear^.X), hwRound(Gear^.Y), 100, 3)
                end;
            end;
    Gear:= Gear^.NextGear
    end;
if isAfterAttack and (KnownExplosion.Radius > 0) then
    with KnownExplosion do
        AddBonus(X, Y, Radius + 10, -Radius);
end;

procedure AwareOfExplosion(x, y, r: LongInt); inline;
begin
    KnownExplosion.X:= x;
    KnownExplosion.Y:= y;
    KnownExplosion.Radius:= r
end;

function RatePlace(Gear: PGear): LongInt;
var i, r: LongInt;
    rate: LongInt;
    gX, gY: real;
begin
gX:= hwFloat2Float(Gear^.X);
gY:= hwFloat2Float(Gear^.Y);
rate:= 0;
for i:= 0 to Pred(bonuses.Count) do
    with bonuses.ar[i] do
        begin
        r:= Radius;
        if abs(gX-X)+abs(gY-Y) < Radius then
            r:= trunc(sqrt(sqr(gX - X)+sqr(gY - Y)));
        if r < 20 then
                inc(rate, Score * Radius)
        else if r < Radius then
                inc(rate, Score * (Radius - r))
        end;
    RatePlace:= rate;
end;

// Wrapper to test various approaches.  If it works reasonably, will just replace.
// Right now, converting to hwFloat is a tad inefficient since the x/y were hwFloat to begin with...
function TestCollExcludingMe(Me: PGear; x, y, r: LongInt): boolean; inline;
var MeX, MeY: LongInt;
begin
    if ((x and LAND_WIDTH_MASK) = 0) and ((y and LAND_HEIGHT_MASK) = 0) then
    begin
        MeX:= hwRound(Me^.X);
        MeY:= hwRound(Me^.Y);
        // We are still inside the hog. Skip radius test
        if ((((x-MeX)*(x-MeX)) + ((y-MeY)*(y-MeY))) < 256) and ((Land[y, x] and $FF00) = 0) then
            exit(false);
    end;
    TestCollExcludingMe:= TestColl(x, y, r)
end;

function TestCollExcludingObjects(x, y, r: LongInt): boolean; inline;
var b: boolean;
begin
    b:= (((x-r) and LAND_WIDTH_MASK) = 0) and (((y-r) and LAND_HEIGHT_MASK) = 0) and (Land[y-r, x-r] and $FF00 <> 0);
    if b then
        exit(true);
    
    b:= (((x-r) and LAND_WIDTH_MASK) = 0) and (((y+r) and LAND_HEIGHT_MASK) = 0) and (Land[y+r, x-r] and $FF00 <> 0);
    if b then
        exit(true);
    
    b:= (((x+r) and LAND_WIDTH_MASK) = 0) and (((y-r) and LAND_HEIGHT_MASK) = 0) and (Land[y-r, x+r] and $FF00 <> 0);
    if b then
        exit(true);
    
    b:= (((x+r) and LAND_WIDTH_MASK) = 0) and (((y+r) and LAND_HEIGHT_MASK) = 0) and (Land[y+r, x+r] and $FF00 <> 0);
    if b then
        exit(true);
    
    TestCollExcludingObjects:= false;
end;

function TestColl(x, y, r: LongInt): boolean; inline;
var b: boolean;
begin
    b:= (((x-r) and LAND_WIDTH_MASK) = 0) and (((y-r) and LAND_HEIGHT_MASK) = 0) and (Land[y-r, x-r] <> 0);
    if b then
        exit(true);
    
    b:= (((x-r) and LAND_WIDTH_MASK) = 0) and (((y+r) and LAND_HEIGHT_MASK) = 0) and (Land[y+r, x-r] <> 0);
    if b then
        exit(true);
    
    b:= (((x+r) and LAND_WIDTH_MASK) = 0) and (((y-r) and LAND_HEIGHT_MASK) = 0) and (Land[y-r, x+r] <> 0);
    if b then
        exit(true);
    
    b:= (((x+r) and LAND_WIDTH_MASK) = 0) and (((y+r) and LAND_HEIGHT_MASK) = 0) and (Land[y+r, x+r] <> 0);
    if b then
        exit(true);
    
    TestColl:= false;
end;

function TestCollWithLand(x, y, r: LongInt): boolean; inline;
var b: boolean;
begin
    b:= (((x-r) and LAND_WIDTH_MASK) = 0) and (((y-r) and LAND_HEIGHT_MASK) = 0) and (Land[y-r, x-r] > 255);
    if b then
        exit(true);
        
    b:= (((x-r) and LAND_WIDTH_MASK) = 0) and (((y+r) and LAND_HEIGHT_MASK) = 0) and (Land[y+r, x-r] > 255);
    if b then
        exit(true);
        
    b:= (((x+r) and LAND_WIDTH_MASK) = 0) and (((y-r) and LAND_HEIGHT_MASK) = 0) and (Land[y-r, x+r] > 255);
    if b then
        exit(true);
        
    b:= (((x+r) and LAND_WIDTH_MASK) = 0) and (((y+r) and LAND_HEIGHT_MASK) = 0) and (Land[y+r, x+r] > 255);
    if b then
        exit(true);

    TestCollWithLand:= false;
end;

function TraceFall(eX, eY: LongInt; x, y, dX, dY: Real; r: LongWord): LongInt;
var skipLandCheck: boolean;
    rCorner: real;
    dmg: LongInt;
begin
    skipLandCheck:= true;
    if x - eX < 0 then dX:= -dX;
    if y - eY < 0 then dY:= -dY;
    // ok. attempt approximate search for an unbroken trajectory into water.  if it continues far enough, assume out of map
    rCorner:= r * 0.75;
    while true do
    begin
        x:= x + dX;
        y:= y + dY;
        dY:= dY + cGravityf;
        skipLandCheck:= skipLandCheck and (r <> 0) and (abs(eX-x) + abs(eY-y) < r) and ((abs(eX-x) < rCorner) or (abs(eY-y) < rCorner));
        if not skipLandCheck and TestCollWithLand(trunc(x), trunc(y), cHHRadius) then
        begin
            if 0.4 < dY then
            begin
                dmg := 1 + trunc((abs(dY) - 0.4) * 70);
                if dmg >= 1 then
                    exit(dmg);
            end;
            exit(0)
        end;
        if (y > cWaterLine) or (x > 4096) or (x < 0) then
            exit(-1);
    end;
end;

function TraceShoveFall(x, y, dX, dY: Real): LongInt;
var dmg, v: LongInt;
begin
v:= random($FFFFFFFF);
    while true do
    begin
        x:= x + dX;
        y:= y + dY;
        dY:= dY + cGravityf;
(*
        if ((trunc(y) and LAND_HEIGHT_MASK) = 0) and ((trunc(x) and LAND_WIDTH_MASK) = 0) then 
            begin
            LandPixels[trunc(y), trunc(x)]:= v;
            UpdateLandTexture(trunc(X), 1, trunc(Y), 1, true);
            end;
*)

        // consider adding dX/dY calc here for fall damage
        if TestCollExcludingObjects(trunc(x), trunc(y), cHHRadius) then
        begin
            if 0.4 < dY then
            begin
                dmg := 1 + trunc((abs(dY) - 0.4) * 70);
                if dmg >= 1 then
                    exit(dmg);
            end;
            exit(0)
        end;
        if (y > cWaterLine) or (x > 4096) or (x < 0) then
            // returning -1 for drowning so it can be considered in the Rate routine
            exit(-1)
    end;
end;

function RateExplosion(Me: PGear; x, y, r: LongInt): LongInt;
begin
    RateExplosion:= RateExplosion(Me, x, y, r, 0);
end;

function RateExplosion(Me: PGear; x, y, r: LongInt; Flags: LongWord): LongInt;
var i, fallDmg, dmg, dmgBase, rate, erasure: LongInt;
    dX, dY, dmgMod: real;
begin
fallDmg:= 0;
dmgMod:= 0.01 * hwFloat2Float(cDamageModifier) * cDamagePercent;
rate:= 0;
// add our virtual position
with Targets.ar[Targets.Count] do
    begin
    Point.x:= hwRound(Me^.X);
    Point.y:= hwRound(Me^.Y);
    Score:= - ThinkingHH^.Health
    end;
// rate explosion
dmgBase:= r + cHHRadius div 2;
if (Flags and afErasesLand <> 0) and (GameFlags and gfSolidLand = 0) then erasure:= r
else erasure:= 0;
for i:= 0 to Targets.Count do
    with Targets.ar[i] do
        begin
        dmg:= 0;
        if abs(Point.x - x) + abs(Point.y - y) < dmgBase then
            dmg:= trunc(dmgMod * min((dmgBase - trunc(sqrt(sqr(Point.x - x)+sqr(Point.y - y)))) div 2, r));

        if dmg > 0 then
            begin
            if Flags and afTrackFall <> 0 then
                begin
                dX:= 0.005 * dmg + 0.01;
                dY:= dX;
                fallDmg:= trunc(TraceFall(x, y, Point.x, Point.y, dX, dY, erasure) * dmgMod);
                end;
            if fallDmg < 0 then // drowning. score healthier hogs higher, since their death is more likely to benefit the AI
                if Score > 0 then
                    inc(rate, KillScore + Score div 10)   // Add a bit of a bonus for bigger hog drownings
                else
                    dec(rate, KillScore * friendlyfactor div 100 - Score div 10) // and more of a punishment for drowning bigger friendly hogs
            else if (dmg+fallDmg) >= abs(Score) then
                if Score > 0 then
                    inc(rate, KillScore)
                else
                    dec(rate, KillScore * friendlyfactor div 100)
            else
                if Score > 0 then
                    inc(rate, dmg+fallDmg)
                else dec(rate, (dmg+fallDmg) * friendlyfactor div 100)
            end;
        end;
RateExplosion:= rate * 1024;
end;

function RateShove(Me: PGear; x, y, r, power, kick: LongInt; gdX, gdY: real; Flags: LongWord): LongInt;
var i, fallDmg, dmg, rate: LongInt;
    dX, dY, dmgMod: real;
begin
fallDmg:= 0;
dX:= gdX * 0.01 * kick;
dY:= gdY * 0.01 * kick;
dmgMod:= 0.01 * hwFloat2Float(cDamageModifier) * cDamagePercent;
rate:= 0;
for i:= 0 to Pred(Targets.Count) do
    with Targets.ar[i] do
      if skip then 
        if (Flags and afSetSkip = 0) then skip:= false else {still skip}
      else  
        begin
        dmg:= 0;
        if abs(Point.x - x) + abs(Point.y - y) < r then
            dmg:= r - trunc(sqrt(sqr(Point.x - x)+sqr(Point.y - y)));

        if dmg > 0 then
            begin
            if (Flags and afSetSkip <> 0) then skip:= true;
            if (Flags and afTrackFall <> 0) and (Score > 0) then 
                fallDmg:= trunc(TraceShoveFall(Point.x, Point.y - 2, dX, dY) * dmgMod);
            if fallDmg < 0 then // drowning. score healthier hogs higher, since their death is more likely to benefit the AI
                if Score > 0 then
                    inc(rate, KillScore + Score div 10)   // Add a bit of a bonus for bigger hog drownings
                else
                    dec(rate, KillScore * friendlyfactor div 100 - Score div 10) // and more of a punishment for drowning bigger friendly hogs
            else if power+fallDmg >= abs(Score) then
                if Score > 0 then
                    inc(rate, KillScore)
                else
                    dec(rate, KillScore * friendlyfactor div 100)
            else
                if Score > 0 then
                    inc(rate, power+fallDmg)
                else
                    dec(rate, (power+fallDmg) * friendlyfactor div 100)
            end;
        end;
RateShove:= rate * 1024
end;

function RateShotgun(Me: PGear; gdX, gdY: real; x, y: LongInt): LongInt;
var i, dmg, fallDmg, baseDmg, rate, erasure: LongInt;
    dX, dY, dmgMod: real;
begin
dmgMod:= 0.01 * hwFloat2Float(cDamageModifier) * cDamagePercent;
rate:= 0;
gdX:= gdX * 0.01;
gdY:= gdX * 0.01;
// add our virtual position
with Targets.ar[Targets.Count] do
    begin
    Point.x:= hwRound(Me^.X);
    Point.y:= hwRound(Me^.Y);
    Score:= - ThinkingHH^.Health
    end;
// rate shot
baseDmg:= cHHRadius + cShotgunRadius + 4;
if GameFlags and gfSolidLand = 0 then erasure:= cShotgunRadius
else erasure:= 0;
for i:= 0 to Targets.Count do
    with Targets.ar[i] do
        begin
        dmg:= 0;
        if abs(Point.x - x) + abs(Point.y - y) < baseDmg then
            begin
            dmg:= min(baseDmg - trunc(sqrt(sqr(Point.x - x)+sqr(Point.y - y))), 25);
            dmg:= trunc(dmg * dmgMod);
            end;
        if dmg > 0 then
            begin
            dX:= gdX * dmg;
            dY:= gdY * dmg;
            if dX < 0 then dX:= dX - 0.01
            else dX:= dX + 0.01;
            fallDmg:= trunc(TraceFall(x, y, Point.x, Point.y, dX, dY, erasure) * dmgMod);
            if fallDmg < 0 then // drowning. score healthier hogs higher, since their death is more likely to benefit the AI
                if Score > 0 then
                    inc(rate, KillScore + Score div 10)   // Add a bit of a bonus for bigger hog drownings
                else
                    dec(rate, KillScore * friendlyfactor div 100 - Score div 10) // and more of a punishment for drowning bigger friendly hogs
            else if (dmg+fallDmg) >= abs(Score) then
                if Score > 0 then
                    inc(rate, KillScore)
                else
                    dec(rate, KillScore * friendlyfactor div 100)
            else
                if Score > 0 then
                    inc(rate, dmg+fallDmg)
            else
                dec(rate, (dmg+fallDmg) * friendlyfactor div 100)
            end;
        end;        
RateShotgun:= rate * 1024;
end;

function RateHammer(Me: PGear): LongInt;
var x, y, i, r, rate: LongInt;
begin
// hammer hit shift against attecker hog is 10
x:= hwRound(Me^.X) + hwSign(Me^.dX) * 10;
y:= hwRound(Me^.Y);
rate:= 0;

for i:= 0 to Pred(Targets.Count) do
    with Targets.ar[i] do
        begin
         // hammer hit radius is 8, shift is 10
        if abs(Point.x - x) + abs(Point.y - y) < 18 then
            r:= trunc(sqrt(sqr(Point.x - x)+sqr(Point.y - y)));

        if r <= 18 then
            if Score > 0 then 
                inc(rate, Score div 3)
            else 
                inc(rate, Score div 3 * friendlyfactor div 100)
        end;
RateHammer:= rate * 1024;
end;

function HHJump(Gear: PGear; JumpType: TJumpType; var GoInfo: TGoInfo): boolean;
var bX, bY: LongInt;
begin
HHJump:= false;
GoInfo.Ticks:= 0;
GoInfo.JumpType:= jmpNone;
bX:= hwRound(Gear^.X);
bY:= hwRound(Gear^.Y);
case JumpType of
    jmpNone: exit(false);
    
    jmpHJump:
        if TestCollisionYwithGear(Gear, -1) = 0 then
        begin
            Gear^.dY:= -_0_2;
            SetLittle(Gear^.dX);
            Gear^.State:= Gear^.State or gstMoving or gstHHJumping;
        end
    else
        exit(false);
        
    jmpLJump:
        begin
            if TestCollisionYwithGear(Gear, -1) <> 0 then
                if not TestCollisionXwithXYShift(Gear, _0, -2, hwSign(Gear^.dX)) then
                    Gear^.Y:= Gear^.Y - int2hwFloat(2)
                else
                    if not TestCollisionXwithXYShift(Gear, _0, -1, hwSign(Gear^.dX)) then
                        Gear^.Y:= Gear^.Y - _1;
            if not (TestCollisionXwithGear(Gear, hwSign(Gear^.dX)) or
               (TestCollisionYwithGear(Gear, -1) <> 0)) then
            begin
                Gear^.dY:= -_0_15;
                Gear^.dX:= SignAs(_0_15, Gear^.dX);
                Gear^.State:= Gear^.State or gstMoving or gstHHJumping
            end
        else
            exit(false)
        end
end;

repeat
    if not (hwRound(Gear^.Y) + cHHRadius < cWaterLine) then
        exit(false);
    if (Gear^.State and gstMoving) <> 0 then
    begin
        if (GoInfo.Ticks = 350) then
            if (not (hwAbs(Gear^.dX) > cLittle)) and (Gear^.dY < -_0_02) then
            begin
                Gear^.dY:= -_0_25;
                Gear^.dX:= SignAs(_0_02, Gear^.dX)
            end;
        if TestCollisionXwithGear(Gear, hwSign(Gear^.dX)) then SetLittle(Gear^.dX);
            Gear^.X:= Gear^.X + Gear^.dX;
        inc(GoInfo.Ticks);
        Gear^.dY:= Gear^.dY + cGravity;
        if Gear^.dY > _0_4 then
            exit(false);
        if (Gear^.dY.isNegative) and (TestCollisionYwithGear(Gear, -1) <> 0) then
            Gear^.dY:= _0;
        Gear^.Y:= Gear^.Y + Gear^.dY;
        if (not Gear^.dY.isNegative) and (TestCollisionYwithGear(Gear, 1) <> 0) then
            begin
            Gear^.State:= Gear^.State and not (gstMoving or gstHHJumping);
            Gear^.dY:= _0;
            case JumpType of
                jmpHJump:
                    if bY - hwRound(Gear^.Y) > 5 then
                        begin
                        GoInfo.JumpType:= jmpHJump;
                        inc(GoInfo.Ticks, 300 + 300); // 300 before jump, 300 after
                        exit(true)
                        end;
                jmpLJump:
                    if abs(bX - hwRound(Gear^.X)) > 30 then
                        begin
                        GoInfo.JumpType:= jmpLJump;
                        inc(GoInfo.Ticks, 300 + 300); // 300 before jump, 300 after
                        exit(true)
                        end
                end;
            exit(false)
            end;
    end;
until false
end;

function HHGo(Gear, AltGear: PGear; var GoInfo: TGoInfo): boolean;
var pX, pY: LongInt;
begin
HHGo:= false;
AltGear^:= Gear^;

GoInfo.Ticks:= 0;
GoInfo.FallPix:= 0;
GoInfo.JumpType:= jmpNone;

repeat
    pX:= hwRound(Gear^.X);
    pY:= hwRound(Gear^.Y);
    if pY + cHHRadius >= cWaterLine then
        exit(false);
        
    // hog is falling    
    if (Gear^.State and gstMoving) <> 0 then
        begin
        inc(GoInfo.Ticks);
        Gear^.dY:= Gear^.dY + cGravity;
        if Gear^.dY > _0_4 then
            begin
            Goinfo.FallPix:= 0;
            // try ljump instead of fall with damage
            HHJump(AltGear, jmpLJump, GoInfo); 
            exit(false)
            end;
        Gear^.Y:= Gear^.Y + Gear^.dY;
        if hwRound(Gear^.Y) > pY then
            inc(GoInfo.FallPix);
        if TestCollisionYwithGear(Gear, 1) <> 0 then
            begin
            inc(GoInfo.Ticks, 410);
            Gear^.State:= Gear^.State and not (gstMoving or gstHHJumping);
            Gear^.dY:= _0;
            // try ljump instead of fall
            HHJump(AltGear, jmpLJump, GoInfo);
            exit(true)
            end;
        continue
        end;
        
        // usual walk
        if (Gear^.Message and gmLeft) <> 0 then
            Gear^.dX:= -cLittle
        else
            if (Gear^.Message and gmRight) <> 0 then
                Gear^.dX:=  cLittle
            else
                exit(false);
                
        if TestCollisionXwithGear(Gear, hwSign(Gear^.dX)) then if (TestCollisionYwithGear(Gear, -1) = 0) then
            begin
            Gear^.Y:= Gear^.Y - _1;
        if TestCollisionXwithGear(Gear, hwSign(Gear^.dX)) then if (TestCollisionYwithGear(Gear, -1) = 0) then
            begin
            Gear^.Y:= Gear^.Y - _1;
        if TestCollisionXwithGear(Gear, hwSign(Gear^.dX)) then if (TestCollisionYwithGear(Gear, -1) = 0) then
            begin
            Gear^.Y:= Gear^.Y - _1;
        if TestCollisionXwithGear(Gear, hwSign(Gear^.dX)) then if (TestCollisionYwithGear(Gear, -1) = 0) then
            begin
            Gear^.Y:= Gear^.Y - _1;
        if TestCollisionXwithGear(Gear, hwSign(Gear^.dX)) then if (TestCollisionYwithGear(Gear, -1) = 0) then
            begin
            Gear^.Y:= Gear^.Y - _1;
        if TestCollisionXwithGear(Gear, hwSign(Gear^.dX)) then if (TestCollisionYwithGear(Gear, -1) = 0) then
            begin
            Gear^.Y:= Gear^.Y - _1;
            if TestCollisionXwithGear(Gear, hwSign(Gear^.dX)) then
                Gear^.Y:= Gear^.Y + _6
            end else Gear^.Y:= Gear^.Y + _5 else
            end else Gear^.Y:= Gear^.Y + _4 else
            end else Gear^.Y:= Gear^.Y + _3 else
            end else Gear^.Y:= Gear^.Y + _2 else
            end else Gear^.Y:= Gear^.Y + _1
            end;

        if not TestCollisionXwithGear(Gear, hwSign(Gear^.dX)) then
        begin
            Gear^.X:= Gear^.X + int2hwFloat(hwSign(Gear^.dX));
            inc(GoInfo.Ticks, cHHStepTicks)
        end;

        // too scared to reformat this part
        if TestCollisionYwithGear(Gear, 1) = 0 then
            begin
            Gear^.Y:= Gear^.Y + _1;
            
        if TestCollisionYwithGear(Gear, 1) = 0 then
            begin
            Gear^.Y:= Gear^.Y + _1;
            
        if TestCollisionYwithGear(Gear, 1) = 0 then
            begin
            Gear^.Y:= Gear^.Y + _1;

        if TestCollisionYwithGear(Gear, 1) = 0 then
            begin
            Gear^.Y:= Gear^.Y + _1;

        if TestCollisionYwithGear(Gear, 1) = 0 then
            begin
            Gear^.Y:= Gear^.Y + _1;

        if TestCollisionYwithGear(Gear, 1) = 0 then
            begin
            Gear^.Y:= Gear^.Y + _1;

        if TestCollisionYwithGear(Gear, 1) = 0 then
            begin
            Gear^.Y:= Gear^.Y - _6;
            Gear^.dY:= _0;
            Gear^.State:= Gear^.State or gstMoving
            end
        end
        end
        end
        end
        end
        end;
        // we have moved for 1 px
        if (pX <> hwRound(Gear^.X)) and ((Gear^.State and gstMoving) = 0) then
            exit(true)
until (pX = hwRound(Gear^.X)) and (pY = hwRound(Gear^.Y)) and ((Gear^.State and gstMoving) = 0);

HHJump(AltGear, jmpHJump, GoInfo);
end;

function AIrndSign(num: LongInt): LongInt;
begin
if random(2) = 0 then
    AIrndSign:=   num
else
    AIrndSign:= - num
end;

procedure initModule;
begin
    friendlyfactor:= 300;
    KnownExplosion.X:= 0;
    KnownExplosion.Y:= 0;
    KnownExplosion.Radius:= 0;
end;

procedure freeModule;
begin

end;

end.