(*
 * Hedgewars, a free turn based strategy game
 * Copyright (c) 2012 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., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *)

{$INCLUDE "options.inc"}

unit uTouch;

interface

uses SysUtils, uConsole, uVariables, SDLh, uFloat, uConsts, uCommands, GLUnit, uTypes, uCaptions, uAmmos, uWorld;


procedure initModule;
procedure freeModule;

procedure ProcessTouch;
procedure NewTurnBeginning;

procedure onTouchDown(x, y: Single; pointerId: TSDL_FingerId);
procedure onTouchMotion(x, y, dx, dy: Single; pointerId: TSDL_FingerId);
procedure onTouchUp(x, y: Single; pointerId: TSDL_FingerId);

function convertToCursorX(x: LongInt): LongInt;
function convertToCursorY(y: LongInt): LongInt;

function addFinger(x,y: Longword; id: TSDL_FingerId): PTouch_Data;
function updateFinger(x,y,dx,dy: Longword; id: TSDL_FingerId): PTouch_Data;
procedure deleteFinger(id: TSDL_FingerId);

procedure onTouchClick(finger: TTouch_Data);
procedure onTouchDoubleClick(finger: TTouch_Data);
procedure onTouchLongClick(finger: TTouch_Data);

function findFinger(id: TSDL_FingerId): PTouch_Data;
procedure aim(finger: TTouch_Data);
function isOnCrosshair(finger: TTouch_Data): boolean;
function isOnCurrentHog(finger: TTouch_Data): boolean;
procedure convertToWorldCoord(var x,y: LongInt; finger: TTouch_Data);
procedure convertToFingerCoord(var x,y: LongInt; oldX, oldY: LongInt);
function fingerHasMoved(finger: TTouch_Data): boolean;
function calculateDelta(finger1, finger2: TTouch_Data): LongInt;
function getSecondFinger(finger: TTouch_Data): PTouch_Data;
function isOnRect(rect: TSDL_Rect; finger: TTouch_Data): boolean;
function isOnRect(x,y,w,h: LongInt; finger: TTouch_Data): boolean;
function isOnWidget(widget: TOnScreenWidget; finger: TTouch_Data): boolean;
procedure printFinger(finger: TTouch_Data);
implementation

const
    clickTime = 200;
    nilFingerId = High(TSDL_FingerId);
    baseRectSize = 96;

var
    rectSize, halfRectSize: LongInt;

    pointerCount : Longword;
    fingers: array of TTouch_Data;
    moveCursor : boolean;
    invertCursor : boolean;

    xTouchClick,yTouchClick : LongInt;
    timeSinceClick : Longword;

    //Pinch to zoom
    pinchSize : LongInt;
    baseZoomValue: GLFloat;

    //aiming
    aimingCrosshair: boolean;
    aimingUp, aimingDown: boolean;
    targetAngle: LongInt;

    buttonsDown: Longword;
    targetting, targetted: boolean; //true when targetting an airstrike or the like

procedure onTouchDown(x, y: Single; pointerId: TSDL_FingerId);
var
    finger: PTouch_Data;
    xr, yr: LongWord;
begin
xr:= round(x * cScreenWidth);
yr:= round(y * cScreenHeight);

finger:= addFinger(xr, yr, pointerId);

inc(buttonsDown);//inc buttonsDown, if we don't see a button down we'll dec it

if isOnCrosshair(finger^) then
begin
    aimingCrosshair:= true;
    aim(finger^);
    moveCursor:= false;
    exit;
end;

if isOnWidget(fireButton, finger^) then
    begin
    ParseTeamCommand('+attack');
    moveCursor:= false;
    finger^.pressedWidget:= @fireButton;
    exit;
    end;
if isOnWidget(arrowLeft, finger^) then
    begin
    ParseTeamCommand('+left');
    moveCursor:= false;
    finger^.pressedWidget:= @arrowLeft;
    exit;
    end;
if isOnWidget(arrowRight, finger^) then
    begin
    ParseTeamCommand('+right');
    moveCursor:= false;
    finger^.pressedWidget:= @arrowRight;
    exit;
    end;
if isOnWidget(arrowUp, finger^) then
    begin
    ParseTeamCommand('+up');
    aimingUp:= true;
    moveCursor:= false;
    finger^.pressedWidget:= @arrowUp;
    exit;
    end;
if isOnWidget(arrowDown, finger^) then
    begin
    ParseTeamCommand('+down');
    aimingDown:= true;
    moveCursor:= false;
    finger^.pressedWidget:= @arrowDown;
    exit;
    end;

if isOnWidget(pauseButton, finger^) then
    begin
    isPaused:= not isPaused;
    moveCursor:= false;
    finger^.pressedWidget:= @pauseButton;
    exit;
    end;

if isOnWidget(utilityWidget, finger^) then
    begin
    finger^.pressedWidget:= @utilityWidget;
    moveCursor:= false;
    if(CurrentHedgehog <> nil) then
        begin
        if Ammoz[CurrentHedgehog^.CurAmmoType].Ammo.Propz and ammoprop_Timerable <> 0 then
            ParseTeamCommand('/timer ' + inttostr((GetCurAmmoEntry(CurrentHedgeHog^)^.Timer div 1000) mod 5 + 1));
        end;
    exit;
    end;
dec(buttonsDown);//no buttonsDown, undo the inc() above
if buttonsDown = 0 then
    begin
    moveCursor:= true;
    case pointerCount of
        1:
            targetting:= not(targetted) and (CurrentHedgehog <> nil) and (Ammoz[CurrentHedgehog^.CurAmmoType].Ammo.Propz and ammoprop_NeedTarget <> 0);
        2:
            begin
            moveCursor:= false;
            pinchSize := calculateDelta(finger^, getSecondFinger(finger^)^);
            baseZoomValue := ZoomValue
            end;
        end;
    end;
end;

procedure onTouchMotion(x, y, dx, dy: Single; pointerId: TSDL_FingerId);
var
    finger, secondFinger: PTouch_Data;
    currentPinchDelta, zoom : Single;
    xr, yr, dxr, dyr: LongWord;
begin
xr:= round(x * cScreenWidth);
yr:= round(y * cScreenHeight);
dxr:= round(dx * cScreenWidth);
dyr:= round(dy * cScreenHeight);

finger:= updateFinger(xr, yr, dxr, dyr, pointerId);
if finger = nil then
    exit;

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 aimingCrosshair then
    begin
        aim(finger^);
        exit
    end;

if (buttonsDown = 0) and (pointerCount = 2) then
    begin
       secondFinger := getSecondFinger(finger^);
       currentPinchDelta := calculateDelta(finger^, secondFinger^) - pinchSize;
       zoom := currentPinchDelta/cScreenWidth;
       ZoomValue := baseZoomValue - (zoom * cMinMaxZoomLevelDelta);
       if ZoomValue < cMaxZoomLevel then
           ZoomValue := cMaxZoomLevel;
       if ZoomValue > cMinZoomLevel then
           ZoomValue := cMinZoomLevel;
    end;

end;

procedure onTouchUp(x,y: Single; pointerId: TSDL_FingerId);
var
    finger: PTouch_Data;
    widget: POnScreenWidget;
    xr, yr: LongWord;
begin
xr:= round(x * cScreenWidth);
yr:= round(y * cScreenHeight);

finger:= updateFinger(xr, yr, 0, 0, pointerId);
if finger = nil then
    exit;

//Check for onTouchClick event
if not(fingerHasMoved(finger^)) then
    begin
    if (RealTicks - finger^.timeSinceDown) < clickTime then
        onTouchClick(finger^)
    else
        onTouchLongClick(finger^);
    end;

if aimingCrosshair then
    begin
    aimingCrosshair:= false;
    ParseTeamCommand('-up');
    ParseTeamCommand('-down');
    dec(buttonsDown);
    end;

widget:= finger^.pressedWidget;
if (buttonsDown > 0) and (widget <> nil) then
    begin
    dec(buttonsDown);

    if widget = @arrowLeft then
        ParseTeamCommand('-left');

    if widget = @arrowRight then
        ParseTeamCommand('-right');

    if widget = @arrowUp then
        ParseTeamCommand('-up');

    if widget = @arrowDown then
        ParseTeamCommand('-down');

    if widget = @fireButton then
        ParseTeamCommand('-attack');

    if widget = @utilityWidget then
        if (CurrentHedgehog <> nil)then
            if(Ammoz[CurrentHedgehog^.CurAmmoType].Ammo.Propz and ammoprop_NeedTarget <> 0)then
                begin
                ParseTeamCommand('put');
                targetted:= true;
                end
            else if (CurAmmoGear <> nil) and (CurAmmoGear^.AmmoType = amSwitch) then
                ParseTeamCommand('switch')
            else WriteLnToConsole(inttostr(ord(Ammoz[CurrentHedgehog^.CurAmmoType].NameId)) + ' ' + inttostr(ord(sidSwitch)));
    end;

if targetting then
    AddCaption('Press the target button to mark the target', cWhiteColor, capgrpAmmoInfo);

deleteFinger(pointerId);
end;

procedure onTouchDoubleClick(finger: TTouch_Data);
begin
finger := finger;//avoid compiler hint
end;

procedure onTouchLongClick(finger: TTouch_Data);
begin
if isOnWidget(jumpWidget, finger) then
    begin
    ParseTeamCommand('ljump');
    exit;
    end;
end;

procedure onTouchClick(finger: TTouch_Data);
begin
//if (RealTicks - timeSinceClick < 300) and (sqrt(sqr(finger.X-xTouchClick) + sqr(finger.Y-yTouchClick)) < 30) then
//    begin
//    onTouchDoubleClick(finger);
//    timeSinceClick:= 0;//we make an assumption there won't be an 'click' in the first 300 ticks(milliseconds)
//    exit;
//    end;

xTouchClick:= finger.x;
yTouchClick:= finger.y;
timeSinceClick:= RealTicks;

if bShowAmmoMenu then
    begin
    if isOnRect(AmmoRect, finger) then
        begin
        CursorPoint.X:= finger.x;
        CursorPoint.Y:= finger.y;
        ParseTeamCommand('put');
        end
    else
        bShowAmmoMenu:= false;
    exit;
    end;

if isOnCurrentHog(finger) or isOnWidget(AMWidget, finger) then
    begin
    bShowAmmoMenu := true;
    exit;
    end;

if isOnWidget(jumpWidget, finger) then
    begin
    ParseTeamCommand('hjump');
    exit;
    end;
end;

function addFinger(x,y: Longword; id: TSDL_FingerId): PTouch_Data;
var
    xCursor, yCursor, index : LongInt;
begin
    //Check array sizes
    if length(fingers) < 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:= RealTicks;
    fingers[pointerCount].pressedWidget:= nil;

    addFinger:= @fingers[pointerCount];
    inc(pointerCount);
end;

function updateFinger(x, y, dx, dy: Longword; id: TSDL_FingerId): PTouch_Data;
var finger : PTouch_Data;
begin
    finger:= findFinger(id);

    if finger <> nil then
        begin
        finger^.x:= convertToCursorX(x);
        finger^.y:= convertToCursorY(y);
        finger^.dx:= dx;
        finger^.dy:= dy;
        end
    else
        WriteLnToConsole('finger ' + inttostr(id) + ' not found');
    updateFinger:= finger
end;

procedure deleteFinger(id: TSDL_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 := 0;
            end
        else fingers[index].id := 0;
            break;
        end;
    end;

end;

procedure NewTurnBeginning;
begin
targetted:= false;
targetting:= false;
SetUtilityWidgetState(amNothing);
end;


procedure ProcessTouch;
var
    deltaAngle: LongInt;
begin
invertCursor := not(bShowAmmoMenu or targetting);
if aimingCrosshair then
    if CurrentHedgehog^.Gear <> nil then
        begin
        deltaAngle:= CurrentHedgehog^.Gear^.Angle - targetAngle;
        if (deltaAngle > -5) and (deltaAngle < 5) then
            begin
                if(aimingUp)then
                    begin
                    aimingUp:= false;
                    ParseTeamCommand('-up');
                    end;
                if(aimingDown)then
                    begin
                    aimingDown:= false;
                    ParseTeamCommand('-down');
                    end
            end
        else
            begin
            if (deltaAngle < 0) then
                begin
                if aimingUp then
                    begin
                    aimingUp:= false;
                    ParseTeamCommand('-up');
                    end;
                if(aimingDown)then
                    begin
                    aimingDown:= true;
                    ParseTeamCommand('-down');
                    end
                end
            else
                begin
                if aimingDown then
                    begin
                    ParseTeamCommand('-down');
                    aimingDown:= false;
                    end;
                if aimingUp then
                    begin
                    aimingUp:= true;
                    ParseTeamCommand('+up');
                    end;
                end;
            end;
        end
    else
        begin
        if aimingUp then
            begin
            ParseTeamCommand('-up');
            aimingUp:= false;
            end;
        if aimingDown then
            begin
            ParseTeamCommand('-down');
            aimingDown:= false;
            end;
        end;
end;

function findFinger(id: TSDL_FingerId): PTouch_Data;
var
    index: LongWord;
begin
    for index:= 0 to length(fingers) do
        if fingers[index].id = id then
            begin
            findFinger:= @fingers[index];
            exit;
            end;
    findFinger:= nil;
end;

procedure aim(finger: TTouch_Data);
var
    hogX, hogY, touchX, touchY, deltaX, deltaY: LongInt;
begin
    if CurrentHedgehog^.Gear <> nil then
        begin
        touchX := 0;//avoid compiler hint
        touchY := 0;
        hogX := hwRound(CurrentHedgehog^.Gear^.X);
        hogY := hwRound(CurrentHedgehog^.Gear^.Y);

        convertToWorldCoord(touchX, touchY, finger);
        deltaX := abs(TouchX-HogX);
        deltaY := TouchY-HogY;

        targetAngle:= (Round(DeltaY / sqrt(sqr(deltaX) + sqr(deltaY)) * 2048) + 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 is proportional to the screen and values are normalized in the onTouch* functions
// - 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:= x - cScreenWidth shr 1;
end;

function convertToCursorY(y: LongInt): LongInt;
begin
    convertToCursorY:= cScreenHeight - y;
end;

function isOnCrosshair(finger: TTouch_Data): boolean;
var
    x, y: LongInt;
begin
    x:= 0;
    y:= 0;
    convertToFingerCoord(x, y, CrosshairX, CrosshairY);
    isOnCrosshair:= isOnRect(x - HalfRectSize, y - HalfRectSize, RectSize, RectSize, finger);
end;

function isOnCurrentHog(finger: TTouch_Data): boolean;
var
    x, y: LongInt;
begin
    x:= 0;
    y:= 0;
    convertToFingerCoord(x, y, hwRound(CurrentHedgehog^.Gear^.X), hwRound(CurrentHedgehog^.Gear^.Y));
    isOnCurrentHog:= isOnRect(x - HalfRectSize, y - HalfRectSize, RectSize, RectSize, finger);
end;

procedure convertToFingerCoord(var x, y : LongInt; oldX, oldY: LongInt);
begin
    x := oldX + WorldDx;
    y := cScreenHeight - oldY - WorldDy;
end;

procedure convertToWorldCoord(var x,y: LongInt; finger: TTouch_Data);
begin
    x := finger.x - WorldDx;
    y := cScreenHeight - finger.y - WorldDy;
end;

//Method to calculate the distance this finger has moved since the downEvent
function fingerHasMoved(finger: TTouch_Data): boolean;
begin
    fingerHasMoved := trunc(sqrt(sqr(finger.X-finger.historicalX) + sqr(finger.y-finger.historicalY))) > 30;
end;

function calculateDelta(finger1, finger2: TTouch_Data): LongInt; inline;
begin
    calculateDelta := Round(sqrt(sqr(finger2.x-finger1.x) + sqr(finger2.y-finger1.y)));
end;

// Under the premise that all pointer ids in pointerIds:TSDL_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: TTouch_Data): PTouch_Data;
begin
    if fingers[0].id = finger.id then
        getSecondFinger := @fingers[1]
    else
        getSecondFinger := @fingers[0];
end;

function isOnRect(rect: TSDL_Rect; finger: TTouch_Data): boolean;
begin
    isOnRect:= isOnRect(rect.x, rect.y, rect.w, rect.h, finger);
end;

function isOnRect(x,y,w,h: LongInt; finger: TTouch_Data): boolean;
begin
    isOnRect:= (finger.x > x)   and
               (finger.x < x + w) and
               (cScreenHeight - finger.y > y) and
               (cScreenHeight - finger.y < y + h);
end;

function isOnWidget(widget: TOnScreenWidget; finger: TTouch_Data): boolean;
begin
    isOnWidget:= widget.show and isOnRect(widget.active, finger);
end;

procedure printFinger(finger: TTouch_Data);
begin
    WriteLnToConsole(Format('id: %d, x: %d y: %d (rel x: %d rel y: %d), time: %d',
                            [finger.id, finger.x, finger.y, finger.historicalX, finger.historicalY, finger.timeSinceDown]));
end;

procedure initModule;
var
    index: Longword;
    //uRenderCoordScaleX, uRenderCoordScaleY: Longword;
begin
    buttonsDown:= 0;
    pointerCount:= 0;

    setLength(fingers, 4);
    for index := 0 to length(fingers) do
        fingers[index].id := 0;

    rectSize:= baseRectSize;
    halfRectSize:= baseRectSize shr 1;
end;

procedure freeModule;
begin
end;

begin
end.