(*

 * 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

// 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;

        dx,dy                    : 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 convertToCursorX(x: LongInt): LongInt;

function convertToCursorY(y: LongInt): LongInt;

function convertToCursorDeltaX(x: LongInt): LongInt;

function convertToCursorDeltaY(y: LongInt): LongInt;

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

function updateFinger(x,y,dx,dy: 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;

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;

function isOnRect(x,y,w,h: LongInt; finger: Touch_Finger): boolean;

procedure printFinger(finger: Touch_Finger);

implementation

const

    clicktime = 200;

    nilFingerId = High(SDL_FingerId);

var

    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: boolean;

    aimingUp, aimingDown: boolean; 

    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 isOnCrosshair(finger^) then

            begin

                aiming:= true;

                aim(finger^);

                exit;

            end;

            if isOnRect(fireButtonX, fireButtonY, fireButtonW, fireButtonH, finger^) then

            begin

                stopFiring:= false;

                exit;

            end;

            if isOnRect(arrowLeftX, arrowLeftY, arrowLeftW, arrowLeftH, finger^) then

            begin

                walkingLeft := true;

                exit;

            end;

            if isOnRect(arrowRightX, arrowRightY, arrowRightW, arrowRightH, finger^) then

            begin

                walkingRight:= true;

                exit;

            end;

            if isOnRect(arrowUpX, arrowUpY, arrowUpW, arrowUpH, finger^) then

            begin

                aimingUp:= true;

                exit;

            end;

            if isOnRect(arrowDownX, arrowDownY, arrowUpW, arrowUpH, finger^) then

            begin

                aimingDown:= true;

                exit;

            end;

            if isOnRect(backjumpX, backjumpY, backjumpW, backjumpH, finger^) then

            begin

                exit;

            end;

            if isOnRect(forwardjumpX, forwardjumpY, forwardjumpW, forwardjumpH, finger^) then

            begin

                exit;

            end;

            moveCursor:= not bShowAmmoMenu;

        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;

begin

finger:= updateFinger(x,y,dx,dy,pointerId);

if moveCursor then

    begin

        if invertCursor then

        begin

            CursorPoint.X := CursorPoint.X - finger^.dx;

            CursorPoint.Y := CursorPoint.Y + finger^.dy;

        end

    else

        begin

            CursorPoint.X := CursorPoint.X + finger^.dx;

            CursorPoint.Y := CursorPoint.Y - finger^.dy;

        end;

        exit //todo change into switch rather than ugly ifs

    end;

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);

var

    finger: PTouch_Finger;

begin

x := x;

y := y;

aiming:= false;

stopFiring:= true;

finger:= updateFinger(x,y,0,0,pointerId);

//Check for onTouchClick event

if ((SDL_GetTicks - finger^.timeSinceDown) < clickTime) AND not(fingerHasMoved(finger^)) then

    onTouchClick(finger^);

deleteFinger(pointerId);

if walkingLeft then

    begin

    walkingLeft := false;

    end;

if walkingRight then

    begin

    walkingRight := false;

    end;

if aimingUp then

    begin

    aimingUp:= false;

    end;

if aimingDown then

    begin

    aimingDown:= false;

    end;

end;

procedure onTouchDoubleClick(finger: Touch_Finger);

begin

finger := finger;//avoid compiler hint

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;

xTouchClick:= finger.x;

yTouchClick:= finger.y;

timeSinceClick:= SDL_GetTicks;

if bShowAmmoMenu then

    begin 

    if isOnRect(AmmoRect.x, AmmoRect.y, AmmoRect.w, AmmoRect.h, finger) then

        begin

        CursorPoint.X:= finger.x;

        CursorPoint.Y:= finger.y;

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

        end

    else

        bShowAmmoMenu:= false;

    exit;

    end;

if isOnCurrentHog(finger) then

    begin

    bShowAmmoMenu := 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 := convertToCursorX(x);

    yCursor := convertToCursorY(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].dx := 0;

    fingers[pointerCount].dy := 0;

    fingers[pointerCount].timeSinceDown:= SDL_GetTicks;

    addFinger:= @fingers[pointerCount];

    inc(pointerCount);

end;

function updateFinger(x,y,dx,dy: Longword; id: SDL_FingerId): PTouch_Finger;

begin

   updateFinger:= findFinger(id);

   updateFinger^.x:= convertToCursorX(x);

   updateFinger^.y:= convertToCursorY(y);

   updateFinger^.dx:= convertToCursorDeltaX(dx);

   updateFinger^.dy:= convertToCursorDeltaY(dy);

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

            //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

    if CurrentHedgehog^.Gear <> nil then

        begin

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

        if (deltaAngle = 0) then 

            begin

            if aimingUp then

                begin

                aimingUp:= false;

                end;

            if aimingDown then

                begin

                aimingDown:= false;

                end

            end

        else

            begin

            if (deltaAngle < 0) then

                begin

                if aimingUp then

                    begin

                    aimingUp:= false;

                    end;

                aimingDown:= true;

                end

            else

                begin

                if aimingDown then

                    begin

                    aimingDown:= false;

                    end;

                aimingUp:= true;

                end; 

            end;

        end

    else  

        begin

        if aimingUp then

            begin

            aimingUp:= false;

            end;

        if aimingDown then

            begin

            aimingDown:= false;

            end;

        end;

if stopFiring then 

    begin

    stopFiring:= false;

    end;

if stopRight then

    begin

    stopRight := false;

    end;

if stopLeft then

    begin

    stopLeft := false;

    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;

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;

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

end;

//These 4 convertToCursor functions convert xy coords from the SDL coordinate system to our CursorPoint coor system

// the SDL coordinate system goes from 0 to 32768 on the x axis and 0 to 32768 on the y axis, (0,0) being top left.

// the CursorPoint coordinate system goes from -cScreenWidth/2 to cScreenWidth/2 on the x axis 

//  and 0 to cScreenHeight on the x axis, (-cScreenWidth, cScreenHeight) being top left,

function convertToCursorX(x: LongInt): LongInt;

begin

    convertToCursorX := round((x/32768)*cScreenWidth) - (cScreenWidth shr 1);

end;

function convertToCursorY(y: LongInt): LongInt;

begin

    convertToCursorY := cScreenHeight - round((y/32768)*cScreenHeight)

end;