{
    This file is part of the Free Pascal run time library.
    Copyright (c) 2006 Karoly Balogh
    member of the Free Pascal development team

    Mouse unit for Amiga/MorphOS

    See the file COPYING.FPC, included in this distribution,
    for details about the copyright.

    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.

 **********************************************************************}
unit Mouse;
interface

{$i mouseh.inc}

implementation

//uses
//   windows,dos,Winevent;

{$i mouse.inc}

//var
//   ChangeMouseEvents : TCriticalSection;
//   LastHandlerMouseEvent : TMouseEvent;

{
procedure MouseEventHandler(var ir:INPUT_RECORD);
  var
     e : TMouseEvent;

  begin
    EnterCriticalSection(ChangeMouseEvents);
    e.x:=ir.Event.MouseEvent.dwMousePosition.x;
    e.y:=ir.Event.MouseEvent.dwMousePosition.y;
    e.buttons:=0;
    e.action:=0;
    if (ir.Event.MouseEvent.dwButtonState and FROM_LEFT_1ST_BUTTON_PRESSED<>0) then
      e.buttons:=e.buttons or MouseLeftButton;
    if (ir.Event.MouseEvent.dwButtonState and FROM_LEFT_2ND_BUTTON_PRESSED<>0) then
      e.buttons:=e.buttons or MouseMiddleButton;
    if (ir.Event.MouseEvent.dwButtonState and RIGHTMOST_BUTTON_PRESSED<>0) then
      e.buttons:=e.buttons or MouseRightButton;

    if (Lasthandlermouseevent.x<>e.x) or (LasthandlerMouseEvent.y<>e.y) then
      e.Action:=MouseActionMove;
    if (LastHandlerMouseEvent.Buttons<>e.Buttons) then
     begin
      if (LasthandlerMouseEvent.Buttons and e.buttons<>LasthandlerMouseEvent.Buttons) then
        e.Action:=MouseActionUp
      else
        e.Action:=MouseActionDown;
     end;


//
//  The mouse event compression here was flawed and could lead
//  to "zero" mouse actions if the new (x,y) was the same as the
//  previous one. (bug 2312)
//

     { can we compress the events? }
   if (PendingMouseEvents>0) and
      (e.buttons=PendingMouseTail^.buttons) and
      (e.action=PendingMouseTail^.action) then
      begin
         PendingMouseTail^.x:=e.x;
         PendingMouseTail^.y:=e.y;
      end
    else
      begin
         if e.action<>0 then
           begin
             LastHandlermouseEvent:=e;

             { what till there is again space in the mouse event queue }
             while PendingMouseEvents>=MouseEventBufSize do
               begin
                 LeaveCriticalSection(ChangeMouseEvents);
                 sleep(0);
                 EnterCriticalSection(ChangeMouseEvents);
               end;

             PutMouseEvent(e);
           end;
         // this should be done in PutMouseEvent, now it is PM
         // inc(PendingMouseEvents);
      end;
    LastMouseEvent:=e;
    LeaveCriticalSection(ChangeMouseEvents);
  end;
}
procedure SysInitMouse;

var
   mode : dword;

begin
{
  // enable mouse events
  GetConsoleMode(StdInputHandle,@mode);
  mode:=mode or ENABLE_MOUSE_INPUT;
  SetConsoleMode(StdInputHandle,mode);

  PendingMouseHead:=@PendingMouseEvent;
  PendingMouseTail:=@PendingMouseEvent;
  PendingMouseEvents:=0;
  FillChar(LastMouseEvent,sizeof(TMouseEvent),0);
  InitializeCriticalSection(ChangeMouseEvents);
  SetMouseEventHandler(@MouseEventHandler);
  ShowMouse;
}
end;


procedure SysDoneMouse;
var
   mode : dword;
begin
{
  HideMouse;
  // disable mouse events
  GetConsoleMode(StdInputHandle,@mode);
  mode:=mode and (not ENABLE_MOUSE_INPUT);
  SetConsoleMode(StdInputHandle,mode);

  SetMouseEventHandler(nil);
  DeleteCriticalSection(ChangeMouseEvents);
}
end;


function SysDetectMouse:byte;
var
  num : dword;
begin
  // Under Amiga/MorphOS, mouse is always there, and it's unable to easily
  // detect number of buttons. So lets report 3, which is common nowadays. (KB)
  SysDetectMouse:=3;
end;


procedure SysGetMouseEvent(var MouseEvent: TMouseEvent);

var
   b : byte;

begin
{
  repeat
    EnterCriticalSection(ChangeMouseEvents);
    b:=PendingMouseEvents;
    LeaveCriticalSection(ChangeMouseEvents);
    if b>0 then
      break
    else
      sleep(50);
  until false;
  EnterCriticalSection(ChangeMouseEvents);
  MouseEvent:=PendingMouseHead^;
  inc(PendingMouseHead);
  if ptrint(PendingMouseHead)=ptrint(@PendingMouseEvent)+sizeof(PendingMouseEvent) then
   PendingMouseHead:=@PendingMouseEvent;
  dec(PendingMouseEvents);

  { LastMouseEvent is already set at the end of the mouse event handler,
    so this code might compare LastMouseEvent with itself leading to
    "empty" events (FK)

  if (LastMouseEvent.x<>MouseEvent.x) or (LastMouseEvent.y<>MouseEvent.y) then
   MouseEvent.Action:=MouseActionMove;
  if (LastMouseEvent.Buttons<>MouseEvent.Buttons) then
   begin
     if (LastMouseEvent.Buttons and MouseEvent.buttons<>LastMouseEvent.Buttons) then
       MouseEvent.Action:=MouseActionUp
     else
       MouseEvent.Action:=MouseActionDown;
   end;
  if MouseEvent.action=0 then
    MousEevent.action:=MouseActionMove; // can sometimes happen due to compression of events.
  LastMouseEvent:=MouseEvent;
  }

  LeaveCriticalSection(ChangeMouseEvents);
}
end;


function SysPollMouseEvent(var MouseEvent: TMouseEvent):boolean;
begin
{
  EnterCriticalSection(ChangeMouseEvents);
  if PendingMouseEvents>0 then
   begin
     MouseEvent:=PendingMouseHead^;
     SysPollMouseEvent:=true;
   end
  else
   SysPollMouseEvent:=false;
  LeaveCriticalSection(ChangeMouseEvents);
}
end;


procedure SysPutMouseEvent(const MouseEvent: TMouseEvent);
begin
{
  if PendingMouseEvents<MouseEventBufSize then
   begin
     PendingMouseTail^:=MouseEvent;
     inc(PendingMouseTail);
     if ptrint(PendingMouseTail)=ptrint(@PendingMouseEvent)+sizeof(PendingMouseEvent) then
      PendingMouseTail:=@PendingMouseEvent;
      { why isn't this done here ?
        so the win32 version do this by hand:}
       inc(PendingMouseEvents);
   end;
}
end;


function SysGetMouseX:word;
begin
{
  EnterCriticalSection(ChangeMouseEvents);
  SysGetMouseX:=LastMouseEvent.x;
  LeaveCriticalSection(ChangeMouseEvents);
}
end;


function SysGetMouseY:word;
begin
{
  EnterCriticalSection(ChangeMouseEvents);
  SysGetMouseY:=LastMouseEvent.y;
  LeaveCriticalSection(ChangeMouseEvents);
}
end;


function SysGetMouseButtons:word;
begin
{
  EnterCriticalSection(ChangeMouseEvents);
  SysGetMouseButtons:=LastMouseEvent.Buttons;
  LeaveCriticalSection(ChangeMouseEvents);
}
end;

const
  SysMouseDriver : TMouseDriver = (
    UseDefaultQueue : False;
    InitDriver      : @SysInitMouse;
    DoneDriver      : @SysDoneMouse;
    DetectMouse     : @SysDetectMouse;
    ShowMouse       : Nil;
    HideMouse       : Nil;
    GetMouseX       : @SysGetMouseX;
    GetMouseY       : @SysGetMouseY;
    GetMouseButtons : @SysGetMouseButtons;
    SetMouseXY      : Nil;
    GetMouseEvent   : @SysGetMouseEvent;
    PollMouseEvent  : @SysPollMouseEvent;
    PutMouseEvent   : @SysPutMouseEvent;
  );

begin
  SetMouseDriver(SysMouseDriver);
end.