(*

 * 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 uAI;

interface

uses uFloat;

procedure initModule;

procedure freeModule;

procedure ProcessBot;

procedure FreeActionsList;

implementation

uses uConsts, SDLh, uAIMisc, uAIAmmoTests, uAIActions,

    uAmmos, SysUtils{$IFNDEF USE_SDLTHREADS} {$IFDEF UNIX}, cthreads{$ENDIF} {$ENDIF}, uTypes,

    uVariables, uCommands, uUtils, uDebug;

var BestActions: TActions;

    CanUseAmmo: array [TAmmoType] of boolean;

    StopThinking: boolean;

{$IFDEF USE_SDLTHREADS} 

    ThinkThread: PSDL_Thread = nil;

{$ELSE}

    ThinkThread: TThreadID;

{$ENDIF}

    hasThread: LongInt;

    StartTicks: Longword;

procedure FreeActionsList;

begin

    AddFileLog('FreeActionsList called');

    if hasThread <> 0 then

    begin

        AddFileLog('Waiting AI thread to finish');

        StopThinking:= true;

        repeat

            SDL_Delay(10)

        until hasThread = 0

    end;

    with CurrentHedgehog^ do

        if Gear <> nil then

            if BotLevel <> 0 then

                StopMessages(Gear^.Message);

    BestActions.Count:= 0;

    BestActions.Pos:= 0

end;

const cBranchStackSize = 12;

type TStackEntry = record

                   WastedTicks: Longword;

                   MadeActions: TActions;

                   Hedgehog: TGear;

                   end;

var Stack: record

           Count: Longword;

           States: array[0..Pred(cBranchStackSize)] of TStackEntry;

           end;

function Push(Ticks: Longword; const Actions: TActions; const Me: TGear; Dir: integer): boolean;

var bRes: boolean;

begin

    bRes:= (Stack.Count < cBranchStackSize) and (Actions.Count < MAXACTIONS - 5);

    if bRes then

        with Stack.States[Stack.Count] do

            begin

            WastedTicks:= Ticks;

            MadeActions:= Actions;

            Hedgehog:= Me;

            Hedgehog.Message:= Dir;

            inc(Stack.Count)

            end;

    Push:= bRes

end;

procedure Pop(var Ticks: Longword; var Actions: TActions; var Me: TGear);

begin

    dec(Stack.Count);

    with Stack.States[Stack.Count] do

        begin

        Ticks:= WastedTicks;

        Actions:= MadeActions;

        Me:= Hedgehog

        end

end;

procedure TestAmmos(var Actions: TActions; Me: PGear; isMoved: boolean);

var BotLevel: Byte;

    ap: TAttackParams;

    Score, i: LongInt;

    a, aa: TAmmoType;

begin

BotLevel:= Me^.Hedgehog^.BotLevel;

windSpeed:= hwFloat2Float(cWindSpeed);

for i:= 0 to Pred(Targets.Count) do

    if (Targets.ar[i].Score >= 0) and (not StopThinking) then

        begin

        with Me^.Hedgehog^ do

            a:= CurAmmoType;

        aa:= a;

{$IFDEF USE_SDLTHREADS}

        SDL_delay(0);    //ThreadSwitch was only a hint

{$ELSE}

        ThreadSwitch();

{$ENDIF}       

        repeat

        if (CanUseAmmo[a]) and

            ((not isMoved) or ((AmmoTests[a].flags and amtest_OnTurn) = 0)) then

            begin

{$HINTS OFF}

            Score:= AmmoTests[a].proc(Me, Targets.ar[i].Point, BotLevel, ap);

{$HINTS ON}

            if Actions.Score + Score > BestActions.Score then

                if (BestActions.Score < 0) or (Actions.Score + Score > BestActions.Score + Byte(BotLevel) * 2048) then

                    begin

                    BestActions:= Actions;

                    inc(BestActions.Score, Score);

                    BestActions.isWalkingToABetterPlace:= false;

                        begin

                        begin

            end;

        if a = High(TAmmoType) then

            a:= Low(TAmmoType)

        else inc(a)

        until (a = aa) or (CurrentHedgehog^.MultiShootAttacks > 0) or // shooting same weapon

        StopThinking

        end

end;

procedure Walk(Me: PGear; var Actions: TActions);

const FallPixForBranching = cHHRadius * 2 + 8;

var

    ticks, maxticks, steps, tmp: Longword;

    BaseRate, BestRate, Rate: integer;

    GoInfo: TGoInfo;

    CanGo: boolean;

    AltMe: TGear;

    BotLevel: Byte;

    a: TAmmoType;

begin

ticks:= 0; // avoid compiler hint

Stack.Count:= 0;

for a:= Low(TAmmoType) to High(TAmmoType) do

    CanUseAmmo[a]:= Assigned(AmmoTests[a].proc) and (HHHasAmmo(Me^.Hedgehog^, a) > 0);

BotLevel:= Me^.Hedgehog^.BotLevel;

if (Me^.State and gstAttacked) = 0 then

    maxticks:= Max(0, TurnTimeLeft - 5000 - LongWord(4000 * BotLevel))

else

    maxticks:= TurnTimeLeft;

if (Me^.State and gstAttacked) = 0 then

    TestAmmos(Actions, Me, false);

BestRate:= RatePlace(Me);

BaseRate:= Max(BestRate, 0);

if (Ammoz[Me^.Hedgehog^.CurAmmoType].Ammo.Propz and ammoprop_NeedTarget) <> 0 then

while (Stack.Count > 0) and (not StopThinking) and (GameFlags and gfArtillery = 0) do

    begin

    Pop(ticks, Actions, Me^);

    AddAction(Actions, Me^.Message, aim_push, 250, 0, 0);

    if (Me^.Message and gmLeft) <> 0 then

        AddAction(Actions, aia_WaitXL, hwRound(Me^.X), 0, 0, 0)

    else

        AddAction(Actions, aia_WaitXR, hwRound(Me^.X), 0, 0, 0);

    steps:= 0;

    while (not StopThinking) do

        begin

{$HINTS OFF}

        CanGo:= HHGo(Me, @AltMe, GoInfo);

{$HINTS ON}

        inc(ticks, GoInfo.Ticks);

        if ticks > maxticks then

            break;

        if (BotLevel < 5) and (GoInfo.JumpType = jmpHJump) then // hjump support

            if Push(ticks, Actions, AltMe, Me^.Message) then

                with Stack.States[Pred(Stack.Count)] do

                    begin

                    if Me^.dX.isNegative then

                        AddAction(MadeActions, aia_LookRight, 0, 200, 0, 0)

                    else

                        AddAction(MadeActions, aia_LookLeft, 0, 200, 0, 0);

                    AddAction(MadeActions, aia_HJump, 0, 305 + random(50), 0, 0);

                    AddAction(MadeActions, aia_HJump, 0, 350, 0, 0);

                    if Me^.dX.isNegative then

                        AddAction(MadeActions, aia_LookLeft, 0, 200, 0, 0)

                    else

                        AddAction(MadeActions, aia_LookRight, 0, 200, 0, 0);

                    end;

        if (BotLevel < 3) and (GoInfo.JumpType = jmpLJump) then // ljump support

            if Push(ticks, Actions, AltMe, Me^.Message) then

                with Stack.States[Pred(Stack.Count)] do

                    AddAction(MadeActions, aia_LJump, 0, 305 + random(50), 0, 0);

        if not CanGo then

            break;

        inc(steps);

         Actions.actions[Pred(Actions.Count)].Param:= hwRound(Me^.X);

         Rate:= RatePlace(Me);

         if Rate > BestRate then

            begin

            BestActions:= Actions;

            BestActions.isWalkingToABetterPlace:= true;

            BestRate:= Rate;

            Me^.State:= Me^.State or gstAttacked // we have better place, go there and do not use ammo

            end

        else if Rate < BestRate then

            break;

        if ((Me^.State and gstAttacked) = 0) and ((steps mod 4) = 0) then

            TestAmmos(Actions, Me, true);

        if GoInfo.FallPix >= FallPixForBranching then

            Push(ticks, Actions, Me^, Me^.Message xor 3); // aia_Left xor 3 = aia_Right

        end;

    if BestRate > BaseRate then

        exit

        end

end;

function Think(Me: Pointer): ptrint;

var BackMe, WalkMe: TGear;

    switchCount: LongInt;

    StartTicks, currHedgehogIndex, itHedgehog, switchesNum, i: Longword;

    switchImmediatelyAvailable: boolean;

    Actions: TActions;

begin

InterlockedIncrement(hasThread);

StartTicks:= GameTicks;

currHedgehogIndex:= CurrentTeam^.CurrHedgehog;

itHedgehog:= currHedgehogIndex;

switchesNum:= 0;

switchImmediatelyAvailable:= (CurAmmoGear <> nil) and (CurAmmoGear^.Kind = gtSwitcher);

switchCount:= HHHasAmmo(PGear(Me)^.Hedgehog^, amSwitch);

if (PGear(Me)^.State and gstAttacked) = 0 then

    if Targets.Count > 0 then

        begin

        // iterate over current team hedgehogs

        repeat

            WalkMe:= CurrentTeam^.Hedgehogs[itHedgehog].Gear^;

            Actions.Count:= 0;

            Actions.Pos:= 0;

            Actions.Score:= 0;

            if switchesNum > 0 then

                begin

                if not switchImmediatelyAvailable  then

                    begin

                    // when AI has to use switcher, make it cost smth unless they have a lot of switches

                    if (switchCount < 10) then Actions.Score:= (-27+switchCount*3)*4000;

                    AddAction(Actions, aia_Weapon, Longword(amSwitch), 300 + random(200), 0, 0);                    

                    AddAction(Actions, aia_attack, aim_push, 300 + random(300), 0, 0);

                    AddAction(Actions, aia_attack, aim_release, 1, 0, 0);

                    end;

                for i:= 1 to switchesNum do

                    AddAction(Actions, aia_Switch, 0, 300 + random(200), 0, 0);

                end;

            Walk(@WalkMe, Actions);

            // find another hog in team

            repeat

                itHedgehog:= Succ(itHedgehog) mod CurrentTeam^.HedgehogsNumber;

            until (itHedgehog = currHedgehogIndex) or (CurrentTeam^.Hedgehogs[itHedgehog].Gear <> nil);

            inc(switchesNum);

        until (not (switchImmediatelyAvailable or (switchCount > 0)))

            or StopThinking 

            or (itHedgehog = currHedgehogIndex)

            or BestActions.isWalkingToABetterPlace;

        if (StartTicks > GameTicks - 1500) and (not StopThinking) then

            SDL_Delay(1000);

        if (BestActions.Score < -1023) and (not BestActions.isWalkingToABetterPlace) then

            begin

            BestActions.Count:= 0;

            AddAction(BestActions, aia_Skip, 0, 250, 0, 0);

            end;

        end else

else

    begin

    BackMe:= PGear(Me)^;

    while (not StopThinking) and (BestActions.Count = 0) do

        begin

        FillBonuses(true);

        WalkMe:= BackMe;

        Actions.Count:= 0;

        Actions.Pos:= 0;

        Actions.Score:= 0;

        Walk(@WalkMe, Actions);

        if not StopThinking then

            SDL_Delay(100)

        end

    end;

PGear(Me)^.State:= PGear(Me)^.State and not gstHHThinking;

Think:= 0;

InterlockedDecrement(hasThread)

end;

procedure StartThink(Me: PGear);

begin

if ((Me^.State and (gstAttacking or gstHHJumping or gstMoving)) <> 0)

or isInMultiShoot then

    exit;

//DeleteCI(Me); // this might break demo

Me^.State:= Me^.State or gstHHThinking;

Me^.Message:= 0;

BestActions.Count:= 0;

BestActions.Pos:= 0;

BestActions.Score:= Low(LongInt);

BestActions.isWalkingToABetterPlace:= false;

StopThinking:= false;

ThinkingHH:= Me;

FillTargets;

if Targets.Count = 0 then

    begin

    OutError('AI: no targets!?', false);

    exit

    end;

FillBonuses((Me^.State and gstAttacked) <> 0);

AddFileLog('Enter Think Thread');

{$IFDEF USE_SDLTHREADS}

ThinkThread := SDL_CreateThread(@Think{$IFDEF SDL13}, nil{$ENDIF}, Me);

{$ELSE}

BeginThread(@Think, Me, ThinkThread);

{$ENDIF}

AddFileLog('Thread started');

end;

procedure ProcessBot;

const cStopThinkTime = 40;

begin

with CurrentHedgehog^ do

    if (Gear <> nil)

    and ((Gear^.State and gstHHDriven) <> 0)

    and (TurnTimeLeft < cHedgehogTurnTime - 50) then

        if ((Gear^.State and gstHHThinking) = 0) then

            if (BestActions.Pos >= BestActions.Count)

            and (TurnTimeLeft > cStopThinkTime) then

                begin

                if Gear^.Message <> 0 then

                    begin

                    StopMessages(Gear^.Message);

                    TryDo((Gear^.Message and gmAllStoppable) = 0, 'Engine bug: AI may break demos playing', true);

                    end;

                if Gear^.Message <> 0 then

                    exit;

                StartThink(Gear);

                StartTicks:= GameTicks

                end else

                    ProcessAction(BestActions, Gear)

        else if ((GameTicks - StartTicks) > cMaxAIThinkTime)

        or (TurnTimeLeft <= cStopThinkTime) then

            StopThinking:= true

end;

procedure initModule;

begin

    hasThread:= 0;

    StartTicks:= 0;

    ThinkThread:= ThinkThread;

end;

procedure freeModule;

begin

    FreeActionsList();

end;

end.