(*

 * Hedgewars, a free turn based strategy game

 * Copyright (c) 2011 Richard Deurwaarder <xeli@xelification.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 uTouch;

interface

uses sysutils, math, uConsole, uVariables, SDLh, uTypes, uFloat, uConsts, uIO, uCommands, GLUnit;

// TODO: this type should be Int64

// TODO: this type should be named TSDL_FingerId

type SDL_FingerId = LongInt;

type

    PTouch_Finger = ^Touch_Finger;

    Touch_Finger = record

        id                       : SDL_FingerId;

        x,y                      : LongInt;

        historicalX, historicalY : LongInt;

        timeSinceDown            : Longword;

        end;

procedure initModule;

procedure ProcessTouch;

procedure onTouchDown(x,y: Longword; pointerId: SDL_FingerId);

procedure onTouchMotion(x,y: Longword; dx,dy: LongInt; pointerId: SDL_FingerId);

procedure onTouchUp(x,y: Longword; pointerId: SDL_FingerId);

function convertToCursor(scale: LongInt; xy: LongInt): LongInt;

function addFinger(x,y: Longword; id: SDL_FingerId): PTouch_Finger;

procedure deleteFinger(id: SDL_FingerId);

procedure onTouchClick(finger: Touch_Finger);

procedure onTouchDoubleClick(finger: Touch_Finger);

function findFinger(id: SDL_FingerId): PTouch_Finger;

procedure aim(finger: Touch_Finger);

function isOnCrosshair(finger: Touch_Finger): boolean;

function isOnCurrentHog(finger: Touch_Finger): boolean;

function isOnFireButton(finger: Touch_Finger): boolean;

procedure convertToWorldCoord(var x,y: hwFloat; finger: Touch_Finger);

procedure convertToFingerCoord(var x,y: hwFloat; oldX, oldY: hwFloat);

function fingerHasMoved(finger: Touch_Finger): boolean;

function calculateDelta(finger1, finger2: Touch_Finger): hwFloat;

function getSecondFinger(finger: Touch_Finger): PTouch_Finger;

procedure printFinger(finger: Touch_Finger);

implementation

const

    clicktime = 200;

    nilFingerId = High(SDL_FingerId);

var

    fireButtonLeft, fireButtonRight, fireButtonTop, fireButtonBottom : LongInt;

    leftButtonBoundary  : LongInt;

    rightButtonBoundary : LongInt;

    topButtonBoundary   : LongInt;

    pointerCount : Longword;

    fingers: array of Touch_Finger;

    moveCursor : boolean;

    invertCursor : boolean;

    xTouchClick,yTouchClick : LongInt;

    timeSinceClick : Longword;

    //Pinch to zoom 

    pinchSize : hwFloat;

    baseZoomValue: GLFloat;

    //aiming

    aiming, movingCrosshair: boolean; 

    crosshairCommand: ShortString;

    targetAngle: LongInt;

    stopFiring: boolean;

    //moving

    stopLeft, stopRight, walkingLeft, walkingRight :  boolean;

procedure onTouchDown(x,y: Longword; pointerId: SDL_FingerId);

var 

    finger: PTouch_Finger;

begin

    finger := addFinger(x,y,pointerId);

    case pointerCount of

        1:

        begin

            moveCursor:= false;

            if bShowAmmoMenu then

            begin

                moveCursor := true;

                exit;

            end;

            if isOnCrosshair(finger^) then

            begin

                aiming:= true;

                exit;

            end;

            if isOnFireButton(finger^) then

            begin

                stopFiring:= false;

                ParseCommand('+attack', true);

                exit;

            end;

            if (finger^.x < leftButtonBoundary) and (finger^.y < 390) then

            begin

                ParseCommand('+left', true);

                walkingLeft := true;

                exit;

            end;

            if finger^.x > rightButtonBoundary then

            begin

                ParseCommand('+right', true);

                walkingRight:= true;

                exit;

            end;

            if finger^.y < topButtonBoundary then

            begin

                ParseCommand('hjump', true);

                exit;

            end;

            moveCursor:= true; 

        end;

        2:

        begin

            aiming:= false;

            stopFiring:= true;

            moveCursor:= false;

            pinchSize := calculateDelta(finger^, getSecondFinger(finger^)^);

            baseZoomValue := ZoomValue

        end;

    end;//end case pointerCount of

end;

procedure onTouchMotion(x,y: Longword;dx,dy: LongInt; pointerId: SDL_FingerId);

var

    finger, secondFinger: PTouch_Finger;

    currentPinchDelta, zoom : hwFloat;

    tmpX, tmpY: LongInt;

begin

    x := x;

    y := y;

    dx := dx;

    dy := dy;

    finger:= findFinger(pointerId);

    tmpX := convertToCursor(cScreenWidth, x);

    tmpY := convertToCursor(cScreenHeight, y);

    if moveCursor then

    begin

        if invertCursor then

        begin

            CursorPoint.X := CursorPoint.X + (finger^.x - tmpX);

            CursorPoint.Y := CursorPoint.Y - (finger^.y - tmpY);

        end

        else

        begin

            CursorPoint.X := CursorPoint.X - (finger^.x - tmpX);

            CursorPoint.Y := CursorPoint.Y + (finger^.y - tmpY);

        end;

        finger^.x := tmpX;

        finger^.y := tmpY;

        exit //todo change into switch rather than ugly ifs

    end;

    finger^.x := tmpX;

    finger^.y := tmpY;

    if aiming then 

    begin

        aim(finger^);

        exit

    end;

    if pointerCount = 2 then

    begin

       secondFinger := getSecondFinger(finger^);

       currentPinchDelta := calculateDelta(finger^, secondFinger^) - pinchSize;

       zoom := currentPinchDelta/cScreenWidth;

       ZoomValue := baseZoomValue - ((hwFloat2Float(zoom) * cMinMaxZoomLevelDelta));

       if ZoomValue < cMaxZoomLevel then ZoomValue := cMaxZoomLevel;

       if ZoomValue > cMinZoomLevel then ZoomValue := cMinZoomLevel;

    end;

end;

procedure onTouchUp(x,y: Longword; pointerId: SDL_FingerId);

begin

    x := x;

    y := y;

    aiming:= false;

    stopFiring:= true;

    deleteFinger(pointerId);

    if walkingLeft then

    begin

        ParseCommand('-left', true);

        walkingLeft := false;

    end;

    if walkingRight then

    begin

        ParseCommand('-right', true);

        walkingRight := false;

    end;

end;

procedure onTouchDoubleClick(finger: Touch_Finger);

begin

    finger := finger;//avoid compiler hint

    ParseCommand('ljump', true);

end;

procedure onTouchClick(finger: Touch_Finger);

begin

    if (SDL_GetTicks - timeSinceClick < 300) and (DistanceI(finger.X-xTouchClick, finger.Y-yTouchClick) < _30) then

    begin

    onTouchDoubleClick(finger);

    exit; 

    end

    else

    begin

        xTouchClick := finger.x;

        yTouchClick := finger.y;

        timeSinceClick := SDL_GetTicks;

    end;

    if bShowAmmoMenu then 

    begin

        doPut(CursorPoint.X, CursorPoint.Y, false); 

        exit

    end;

    if isOnCurrentHog(finger) then

    begin

        bShowAmmoMenu := true;

        exit;

    end;

    if finger.y < topButtonBoundary then

    begin

        ParseCommand('hjump', true);

        exit;

    end;

end;

function addFinger(x,y: Longword; id: SDL_FingerId): PTouch_Finger;

var 

    xCursor, yCursor, index : LongInt;

begin

    //Check array sizes

    if length(fingers) < Integer(pointerCount) then 

    begin

        setLength(fingers, length(fingers)*2);

        for index := length(fingers) div 2 to length(fingers) do fingers[index].id := nilFingerId;

    end;

    xCursor := convertToCursor(cScreenWidth, x);

    yCursor := convertToCursor(cScreenHeight, y);

    //on removing fingers, all fingers are moved to the left

    //with dynamic arrays being zero based, the new position of the finger is the old pointerCount

    fingers[pointerCount].id := id;

    fingers[pointerCount].historicalX := xCursor;

    fingers[pointerCount].historicalY := yCursor;

    fingers[pointerCount].x := xCursor;

    fingers[pointerCount].y := yCursor;

    fingers[pointerCount].timeSinceDown:= SDL_GetTicks;

    addFinger:= @fingers[pointerCount];

    inc(pointerCount);

end;

procedure deleteFinger(id: SDL_FingerId);

var

    index : Longword;

begin

    dec(pointerCount);

    for index := 0 to pointerCount do

    begin

         if fingers[index].id = id then

         begin

             //Check for onTouchClick event

             if ((SDL_GetTicks - fingers[index].timeSinceDown) < clickTime) AND  

                 not(fingerHasMoved(fingers[index])) then onTouchClick(fingers[index]);

             //put the last finger into the spot of the finger to be removed, 

             //so that all fingers are packed to the far left

             if  pointerCount <> index then

             begin

                fingers[index].id := fingers[pointerCount].id;    

                fingers[index].x := fingers[pointerCount].x;    

                fingers[index].y := fingers[pointerCount].y;    

                fingers[index].historicalX := fingers[pointerCount].historicalX;    

                fingers[index].historicalY := fingers[pointerCount].historicalY;    

                fingers[index].timeSinceDown := fingers[pointerCount].timeSinceDown;

                fingers[pointerCount].id := nilFingerId;

             end

             else fingers[index].id := nilFingerId;

             break;

         end;

    end;

end;

procedure ProcessTouch;

var

    deltaAngle: LongInt;

begin

    invertCursor := not(bShowAmmoMenu);

    if aiming then

    begin

        if CurrentHedgehog^.Gear <> nil then

        begin

            deltaAngle:= CurrentHedgehog^.Gear^.Angle - targetAngle;

            if (deltaAngle <> 0) and not(movingCrosshair) then 

            begin

                ParseCommand('+' + crosshairCommand, true);

                movingCrosshair := true;

            end

            else 

                if movingCrosshair then 

                begin

                    ParseCommand('-' + crosshairCommand, true);

                    movingCrosshair:= false;

                end;

        end;

    end

    else if movingCrosshair then 

    begin

        ParseCommand('-' + crosshairCommand, true);

        movingCrosshair := false;

    end;

    if stopFiring then 

    begin

        ParseCommand('-attack', true);

        stopFiring:= false;

    end;

    if stopRight then

    begin

        stopRight := false;

        ParseCommand('-right', true);

    end;

    if stopLeft then

    begin

        stopLeft := false;

        ParseCommand('-left', true);

    end;

end;

function findFinger(id: SDL_FingerId): PTouch_Finger;

var

    index: LongWord;

begin

   for index := 0 to High(fingers) do

       if fingers[index].id = id then 

       begin

           findFinger := @fingers[index];

           break;

       end;

end;

procedure aim(finger: Touch_Finger);

var 

    hogX, hogY, touchX, touchY, deltaX, deltaY, tmpAngle: hwFloat;

    tmp: ShortString;

begin

    if CurrentHedgehog^.Gear <> nil then

    begin

        touchX := _0;//avoid compiler hint

        touchY := _0;

        hogX := CurrentHedgehog^.Gear^.X;

        hogY := CurrentHedgehog^.Gear^.Y;

        convertToWorldCoord(touchX, touchY, finger);

        deltaX := hwAbs(TouchX-HogX);

        deltaY := (TouchY-HogY);

        tmpAngle:= DeltaY / Distance(deltaX, deltaY) *_2048;

        targetAngle:= (hwRound(tmpAngle) + 2048) div 2;

        tmp := crosshairCommand;

        if CurrentHedgehog^.Gear^.Angle - targetAngle < 0 then crosshairCommand := 'down'

        else crosshairCommand:= 'up';

        if movingCrosshair and (tmp <> crosshairCommand) then 

        begin

            ParseCommand('-' + tmp, true);

            movingCrosshair := false;

        end;

    end; //if CurrentHedgehog^.Gear <> nil

end;

function convertToCursor(scale: LongInt; xy: LongInt): LongInt;

begin

    convertToCursor := round(xy/32768*scale)

end;

function isOnFireButton(finger: Touch_Finger): boolean;

begin

    isOnFireButton:= (finger.x <= fireButtonRight) and (finger.x >= fireButtonLeft) and (finger.y <= fireButtonBottom) and (finger.y >= fireButtonTop);

end;

function isOnCrosshair(finger: Touch_Finger): boolean;

var

    x,y : hwFloat;

begin

    x := _0;//avoid compiler hint

    y := _0;

    convertToFingerCoord(x, y, int2hwFloat(CrosshairX), int2hwFloat(CrosshairY));

    isOnCrosshair:= Distance(int2hwFloat(finger.x)-x, int2hwFloat(finger.y)-y) < _50;

end;

function isOnCurrentHog(finger: Touch_Finger): boolean;

var

    x,y : hwFloat;

begin

    x := _0;

    y := _0;

    convertToFingerCoord(x, y, CurrentHedgehog^.Gear^.X, CurrentHedgehog^.Gear^.Y);

    isOnCurrentHog := Distance(int2hwFloat(finger.X)-x, int2hwFloat(finger.Y)-y) < _50;

end;

procedure convertToFingerCoord(var x,y : hwFloat; oldX, oldY: hwFloat);

begin

    x := oldX + int2hwFloat(WorldDx + (cScreenWidth div 2));

    y := oldY + int2hwFloat(WorldDy);

end;

procedure convertToWorldCoord(var x,y: hwFloat; finger: Touch_Finger);

begin

//if x <> nil then 

    x := int2hwFloat((finger.x-WorldDx) - (cScreenWidth div 2));

//if y <> nil then 

    y := int2hwFloat(finger.y-WorldDy);

end;

//Method to calculate the distance this finger has moved since the downEvent

function fingerHasMoved(finger: Touch_Finger): boolean;

begin

    fingerHasMoved := trunc(sqrt(Power(finger.X-finger.historicalX,2) + Power(finger.y-finger.historicalY, 2))) > 330;

end;

function calculateDelta(finger1, finger2: Touch_Finger): hwFloat; inline;

begin

    calculateDelta := DistanceI(finger2.x-finger1.x, finger2.y-finger1.y);

end;

// Under the premise that all pointer ids in pointerIds:SDL_FingerId are packed to the far left.

// If the pointer to be ignored is not pointerIds[0] the second must be there

function getSecondFinger(finger: Touch_Finger): PTouch_Finger;

begin

    if fingers[0].id = finger.id then getSecondFinger := @fingers[1]

    else getSecondFinger := @fingers[0];

end;

procedure printFinger(finger: Touch_Finger);

begin

    WriteToConsole(Format('id:%d, (%d,%d), (%d,%d), time: %d', [finger.id, finger.x, finger.y, finger.historicalX, finger.historicalY, finger.timeSinceDown]));

end;