{
    $Id$
    This file is part of the Free Pascal run time library.
    Copyright (c) 1999-2000 by Florian Klaempfl
    member of the Free Pascal development team

    Video unit for linux

    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 Video;

interface

{$i videoh.inc}

implementation

uses
  Unix, Strings, TermInfo;

{$i video.inc}

var
  LastCursorType : byte;
  TtyFd: Longint;
  Console: Boolean;
{$ifdef logging}
  f: file;

const
  logstart: string = '';
  nl: char = #10;
  logend: string = #10#10;
{$endif logging}

{$ifdef I386}
{$ASMMODE ATT}
{$endif I386}

const

  can_delete_term : boolean = false;
  ACSIn : string = '';
  ACSOut : string = '';
  InACS : boolean =false;

function IsACS(var ch,ACSchar : char): boolean;
begin
  IsACS:=false;
  case ch of
    #24, #30: {}
      ch:='^';
    #25, #31: {}
      ch:='v';
    #26, #16: {Never introduce a ctrl-Z ... }
      ch:='>';
    {#27,needed in Escape sequences} #17: {}
      ch:='<';
    #176, #177, #178: {°±²}
      begin
        IsACS:=true;
        ACSChar:='a';
      end;
    #180, #181, #182, #185: {´µ¶¹}
      begin
        IsACS:=true;
        ACSChar:='u';
      end;
    #183, #184, #187, #191: {·¸»¿}
      begin
        IsACS:=true;
        ACSChar:='k';
      end;
    #188, #189, #190, #217: {¼½¾Ù}
      begin
        IsACS:=true;
        ACSChar:='j';
      end;
    #192, #200, #211, #212: {ÀÈÓÔ}
      begin
        IsACS:=true;
        ACSChar:='m';
      end;
    #193, #202, #207, #208: {ÁÊÏÐ}
      begin
        IsACS:=true;
        ACSChar:='v';
      end;
    #194, #203, #209, #210: {ÂËÑÒ}
      begin
        IsACS:=true;
        ACSChar:='w';
      end;
    #195, #198, #199, #204: {ÃÆÇÌ}
      begin
        IsACS:=true;
        ACSChar:='t';
      end;
    #196, #205: {ÄÍ}
      begin
        IsACS:=true;
        ACSChar:='q';
      end;
    #179, #186: {³º}
      begin
        IsACS:=true;
        ACSChar:='x';
      end;
    #197, #206, #215, #216: {ÅÎ×Ø}
      begin
        IsACS:=true;
        ACSChar:='n';
      end;
    #201, #213, #214, #218: {ÉÕÖÚ}
      begin
        IsACS:=true;
        ACSChar:='l';
      end;
    #254: { þ }
      begin
        ch:='*';
      end;
    { Shadows for Buttons }
    #220: { Ü }
      begin
        IsACS:=true;
        ACSChar:='a';
      end;
    #223: { ß }
      begin
        IsACS:=true;
        ACSChar:='a';
      end;
  end;
end;


function SendEscapeSeqNdx(Ndx: Word) : boolean;
var
  P,pdelay: PChar;
begin
  SendEscapeSeqNdx:=false;
  if not assigned(cur_term_Strings) then
    exit{RunError(219)};
  P:=cur_term_Strings^[Ndx];
  if assigned(p) then
   begin { Do not transmit the delays }
     pdelay:=strpos(p,'$<');
     if assigned(pdelay) then
       pdelay^:=#0;
     fdWrite(TTYFd, P^, StrLen(P));
     SendEscapeSeqNdx:=true;
     if assigned(pdelay) then
       pdelay^:='$';
   end;
end;


procedure SendEscapeSeq(const S: String);
begin
  fdWrite(TTYFd, S[1], Length(S));
end;


Function IntStr(l:longint):string;
var
  s : string;
begin
  Str(l,s);
  IntStr:=s;
end;


Function XY2Ansi(x,y,ox,oy:longint):String;
{
  Returns a string with the escape sequences to go to X,Y on the screen
}
Begin
  if y=oy then
   begin
     if x=ox then
      begin
        XY2Ansi:='';
        exit;
      end;
     if x=1 then
      begin
        XY2Ansi:=#13;
        exit;
      end;
     if x>ox then
      begin
        XY2Ansi:=#27'['+IntStr(x-ox)+'C';
        exit;
      end
     else
      begin
        XY2Ansi:=#27'['+IntStr(ox-x)+'D';
        exit;
      end;
   end;
  if x=ox then
   begin
     if y>oy then
      begin
        XY2Ansi:=#27'['+IntStr(y-oy)+'B';
        exit;
      end
     else
      begin
        XY2Ansi:=#27'['+IntStr(oy-y)+'A';
        exit;
      end;
   end;
  if (x=1) and (oy+1=y) then
   XY2Ansi:=#13#10
  else
   XY2Ansi:=#27'['+IntStr(y)+';'+IntStr(x)+'H';
End;



const
  AnsiTbl : string[8]='04261537';
Function Attr2Ansi(Attr,OAttr:longint):string;
{
  Convert Attr to an Ansi String, the Optimal code is calculate
  with use of the old OAttr
}
var
  hstr : string[16];
  OFg,OBg,Fg,Bg : longint;

  procedure AddSep(ch:char);
  begin
    if length(hstr)>0 then
     hstr:=hstr+';';
    hstr:=hstr+ch;
  end;

begin
  if Attr=OAttr then
   begin
     Attr2Ansi:='';
     exit;
   end;
  Hstr:='';
  Fg:=Attr and $f;
  Bg:=Attr shr 4;
  OFg:=OAttr and $f;
  OBg:=OAttr shr 4;
  if (OFg<>7) or (Fg=7) or ((OFg>7) and (Fg<8)) or ((OBg>7) and (Bg<8)) then
   begin
     hstr:='0';
     OFg:=7;
     OBg:=0;
   end;
  if (Fg>7) and (OFg<8) then
   begin
     AddSep('1');
     OFg:=OFg or 8;
   end;
  if (Bg and 8)<>(OBg and 8) then
   begin
     AddSep('5');
     OBg:=OBg or 8;
   end;
  if (Fg<>OFg) then
   begin
     AddSep('3');
     hstr:=hstr+AnsiTbl[(Fg and 7)+1];
   end;
  if (Bg<>OBg) then
   begin
     AddSep('4');
     hstr:=hstr+AnsiTbl[(Bg and 7)+1];
   end;
  if hstr='0' then
   hstr:='';
  Attr2Ansi:=#27'['+hstr+'m';
end;

procedure UpdateTTY(Force:boolean);
type
  tchattr=packed record
{$ifdef ENDIAN_LITTLE}
    ch : char;
    attr : byte;
{$else}
    attr : byte;
    ch : char;
{$endif}
  end;
var
  outbuf   : array[0..1023+255] of char;
  chattr   : tchattr;
  skipped  : boolean;
  outptr,
  spaces,
  eol,
  x,y,
  LastX,LastY,
  SpaceAttr,
  LastAttr : longint;
  p,pold   : pvideocell;


procedure TransformUsingACS(var st : string);
var
  res : string;
  i : longint;
  ch,ACSch : char;
begin
  res:='';
  for i:=1 to length(st) do
    begin
      ch:=st[i];
      if IsACS(ch,ACSch) then
        begin
          if not InACS then
            begin
              res:=res+ACSIn;
              InACS:=true;
            end;
          res:=res+ACSch;
        end
      else
        begin
          if InACS then
            begin
              res:=res+ACSOut+Attr2Ansi(LastAttr,0);
              InACS:=false;
            end;
          res:=res+ch;
        end;
    end;
  st:=res;
end;



  procedure outdata(hstr:string);
  begin
    while (eol>0) do
     begin
       hstr:=#13#10+hstr;
       dec(eol);
     end;
    if NoExtendedFrame and (ACSIn<>'') and (ACSOut<>'') then
      TransformUsingACS(Hstr);
    move(hstr[1],outbuf[outptr],length(hstr));
    inc(outptr,length(hstr));
    if outptr>=1024 then
     begin
{$ifdef logging}
       blockwrite(f,logstart[1],length(logstart));
       blockwrite(f,nl,1);
       blockwrite(f,outptr,sizeof(outptr));
       blockwrite(f,nl,1);
       blockwrite(f,outbuf,outptr);
       blockwrite(f,nl,1);
{$endif logging}
       fdWrite(TTYFd,outbuf,outptr);
       outptr:=0;
     end;
  end;

  procedure OutClr(c:byte);
  begin
    if c=LastAttr then
     exit;
    OutData(Attr2Ansi(c,LastAttr));
    LastAttr:=c;
  end;

  procedure OutSpaces;
  begin
    if (Spaces=0) then
     exit;
    OutClr(SpaceAttr);
    OutData(Space(Spaces));
    LastX:=x;
    LastY:=y;
    Spaces:=0;
  end;

begin
  OutPtr:=0;
  Eol:=0;
  skipped:=true;
  p:=PVideoCell(VideoBuf);
  pold:=PVideoCell(OldVideoBuf);
{ init Attr and X,Y }
  SendEscapeSeq(#27'[m'{#27'[H'});
  LastAttr:=7;
  LastX:=-1;
  LastY:=-1;
  for y:=1 to ScreenHeight do
   begin
     SpaceAttr:=0;
     Spaces:=0;
     for x:=1 to ScreenWidth do
      begin
        if (not force) and (p^=pold^) then
         begin
           if (Spaces>0) then
            OutSpaces;
           skipped:=true;
         end
        else
         begin
           if skipped then
            begin
              OutData(XY2Ansi(x,y,LastX,LastY));
              LastX:=x;
              LastY:=y;
              skipped:=false;
            end;
           chattr:=tchattr(p^);
           if chattr.ch in [#0,#255] then
            chattr.ch:=' ';
           if chattr.ch=' ' then
            begin
              if Spaces=0 then
               SpaceAttr:=chattr.Attr;
              if (chattr.attr and $f0)=(spaceattr and $f0) then
               chattr.Attr:=SpaceAttr
              else
               begin
                 OutSpaces;
                 SpaceAttr:=chattr.Attr;
               end;
              inc(Spaces);
            end
           else
            begin
              if (Spaces>0) then
               OutSpaces;
              if ord(chattr.ch)<32 then
                begin
                  Chattr.Attr:= $ff xor Chattr.Attr;
                  ChAttr.ch:= chr(ord(chattr.ch)+ord('A')-1);
                end;
              if LastAttr<>chattr.Attr then
               OutClr(chattr.Attr);
              OutData(chattr.ch);
              LastX:=x+1;
              LastY:=y;
            end;
           p^:=tvideocell(chattr);
         end;
        inc(p);
        inc(pold);
      end;
     if (Spaces>0) then
      OutSpaces;
     if force then
      inc(eol)
     else
      skipped:=true;
   end;
  eol:=0;
  OutData(XY2Ansi(CursorX,CursorY,LastX,LastY));
{$ifdef logging}
  blockwrite(f,logstart[1],length(logstart));
  blockwrite(f,nl,1);
  blockwrite(f,outptr,sizeof(outptr));
  blockwrite(f,nl,1);
  blockwrite(f,outbuf,outptr);
  blockwrite(f,nl,1);
{$endif logging}
  fdWrite(TTYFd,outbuf,outptr);
  if InACS then
    SendEscapeSeqNdx(exit_alt_charset_mode);
end;

var
  InitialVideoTio, preInitVideoTio, postInitVideoTio: Unix.termios;
  inputRaw, outputRaw: boolean;

procedure saveRawSettings(const tio: Unix.termios);
Begin
  with tio do
   begin
     inputRaw :=
       ((c_iflag and (IGNBRK or BRKINT or PARMRK or ISTRIP or
                                INLCR or IGNCR or ICRNL or IXON)) = 0) and
       ((c_lflag and (ECHO or ECHONL or ICANON or ISIG or IEXTEN)) = 0);
     outPutRaw :=
       ((c_oflag and OPOST) = 0) and
       ((c_cflag and (CSIZE or PARENB)) = 0) and
       ((c_cflag and CS8) <> 0);
   end;
end;

procedure restoreRawSettings(tio: Unix.termios);
begin
  with tio do
    begin
      if inputRaw then
        begin
          c_iflag := c_iflag and (not (IGNBRK or BRKINT or PARMRK or ISTRIP or
            INLCR or IGNCR or ICRNL or IXON));
          c_lflag := c_lflag and
            (not (ECHO or ECHONL or ICANON or ISIG or IEXTEN));
       end;
     if outPutRaw then
       begin
         c_oflag := c_oflag and not(OPOST);
         c_cflag := c_cflag and not(CSIZE or PARENB) or CS8;
       end;
   end;
  TCSetAttr(1,TCSANOW,tio);
end;

procedure TargetEntry;
begin
  TCGetAttr(1,InitialVideoTio);
end;

procedure TargetExit;
begin
  TCSetAttr(1,TCSANOW,InitialVideoTio);
end;

procedure prepareInitVideo;
begin
  TCGetAttr(1,preInitVideoTio);
  saveRawSettings(preInitVideoTio);
end;

procedure videoInitDone;
begin
  TCGetAttr(1,postInitVideoTio);
  restoreRawSettings(postInitVideoTio);
end;

procedure prepareDoneVideo;
var
  tio: Unix.termios;
begin
  TCGetAttr(1,tio);
  saveRawSettings(tio);
  TCSetAttr(1,TCSANOW,postInitVideoTio);
end;

procedure doneVideoDone;
begin
  restoreRawSettings(preInitVideoTio);
end;

procedure SysInitVideo;
const
  fontstr : string[3]=#27'(K';
var
  ThisTTY: String[30];
  FName: String;
  WS: packed record
    ws_row, ws_col, ws_xpixel, ws_ypixel: Word;
  end;
  Err: Longint;
  prev_term : TerminalCommon_ptr1;
begin
{$ifndef CPUI386}
  LowAscii:=false;
{$endif CPUI386}
  { check for tty }
  ThisTTY:=TTYName(stdinputhandle);
  if IsATTY(stdinputhandle) then
   begin
     { save current terminal characteristics and remove rawness }
     prepareInitVideo;
     { write code to set a correct font }
     fdWrite(stdoutputhandle,fontstr[1],length(fontstr));
     { running on a tty, find out whether locally or remotely }
     if (Copy(ThisTTY, 1, 8) = '/dev/tty') and
        (ThisTTY[9] >= '0') and (ThisTTY[9] <= '9') then
      begin
        { running on the console }
        FName:='/dev/vcsa' + ThisTTY[9];
        TTYFd:=fdOpen(FName, Octal(666), Open_RdWr); { open console }
      end
     else
      TTYFd:=-1;
     if TTYFd<>-1 then
      Console:=true
     else
      begin
        { running on a remote terminal, no error with /dev/vcsa }
        Console:=False;
        LowAscii:=false;
        TTYFd:=stdoutputhandle;
      end;
     ioctl(stdinputhandle, TIOCGWINSZ, @WS);
     if WS.ws_Col=0 then
      WS.ws_Col:=80;
     if WS.ws_Row=0 then
      WS.ws_Row:=25;
     ScreenWidth:=WS.ws_Col;
     { TDrawBuffer only has FVMaxWidth elements
       larger values lead to crashes }
     if ScreenWidth> FVMaxWidth then
       ScreenWidth:=FVMaxWidth;
     ScreenHeight:=WS.ws_Row;
     CursorX:=1;
     CursorY:=1;
     ScreenColor:=True;
     { Start with a clear screen }
     if not Console then
      begin
        prev_term:=cur_term;
        setupterm(nil, stdoutputhandle, err);
        can_delete_term:=assigned(prev_term) and (prev_term<>cur_term);
        SendEscapeSeqNdx(cursor_home);
        SendEscapeSeqNdx(cursor_normal);
        SendEscapeSeqNdx(cursor_visible);
        SendEscapeSeqNdx(enter_ca_mode);
        SetCursorType(crUnderLine);
      end
     else if not assigned(cur_term) then
       begin
         setupterm(nil, stdoutputhandle, err);
         can_delete_term:=false;
       end;
     if assigned(cur_term_Strings) then
       begin
         ACSIn:=StrPas(cur_term_Strings^[enter_alt_charset_mode]);
         ACSOut:=StrPas(cur_term_Strings^[exit_alt_charset_mode]);
         if (ACSIn<>'') and (ACSOut<>'') then
           SendEscapeSeqNdx(ena_acs);
         if pos('$<',ACSIn)>0 then
           ACSIn:=Copy(ACSIn,1,Pos('$<',ACSIn)-1);
         if pos('$<',ACSOut)>0 then
           ACSOut:=Copy(ACSOut,1,Pos('$<',ACSOut)-1);
       end
     else
       begin
         ACSIn:='';
         ACSOut:='';
       end;
{$ifdef logging}
     assign(f,'video.log');
     rewrite(f,1);
{$endif logging}
     { save new terminal characteristics and possible restore rawness }
     videoInitDone;
   end
  else
   ErrorCode:=errVioInit; { not a TTY }
end;

procedure SysDoneVideo;
begin
  prepareDoneVideo;
  if Console then
   SetCursorPos(1,1)
  else
   begin
     SendEscapeSeqNdx(exit_ca_mode);
     SendEscapeSeqNdx(cursor_home);
     SendEscapeSeqNdx(cursor_normal);
     SendEscapeSeqNdx(cursor_visible);
     SetCursorType(crUnderLine);
     SendEscapeSeq(#27'[H');
   end;
  ACSIn:='';
  ACSOut:='';
  doneVideoDone;
  if can_delete_term then
    begin
      del_curterm(cur_term);
      can_delete_term:=false;
    end;
{$ifdef logging}
  close(f);
{$endif logging}
end;


procedure SysClearScreen;
begin
  if Console then
    UpdateScreen(true)
  else
    begin
    SendEscapeSeq(#27'[0m');
    SendEscapeSeqNdx(clear_screen);
    end;
end;


procedure SysUpdateScreen(Force: Boolean);
var
  DoUpdate : boolean;
  i : longint;
  p1,p2 : plongint;
begin
  if not force then
   begin
{$ifdef i386}
     asm
          movl    VideoBuf,%esi
          movl    OldVideoBuf,%edi
          movl    VideoBufSize,%ecx
          shrl    $2,%ecx
          repe
          cmpsl
          setne   DoUpdate
     end;
{$else not i386}
     p1:=plongint(VideoBuf);
     p2:=plongint(OldVideoBuf);
     for i:=0 to VideoBufSize div 2 do
       if (p1^<>p2^) then
         begin
           DoUpdate:=true;
           break;
         end
       else
         begin
           { Inc does add sizeof(longint) to both pointer values }
           inc(p1);
           inc(p2);
         end;
{$endif not i386}
   end
  else
   DoUpdate:=true;
  if not DoUpdate then
   exit;
  if Console then
   begin
     fdSeek(TTYFd, 4, Seek_Set);
     fdWrite(TTYFd, VideoBuf^,VideoBufSize);
   end
  else
   begin
     UpdateTTY(force);
   end;
  Move(VideoBuf^, OldVideoBuf^, VideoBufSize);
end;


function SysGetCapabilities: Word;
begin
{ about cpColor... we should check the terminfo database... }
  SysGetCapabilities:=cpUnderLine + cpBlink + cpColor;
end;


procedure SysSetCursorPos(NewCursorX, NewCursorY: Word);
var
  Pos : array [1..2] of Byte;
begin
  if Console then
   begin
     fdSeek(TTYFd, 2, Seek_Set);
     Pos[1]:=NewCursorX;
     Pos[2]:=NewCursorY;
     fdWrite(TTYFd, Pos, 2);
   end
  else
   begin
     { newcursorx,y is 0 based ! }
     SendEscapeSeq(XY2Ansi(NewCursorX+1,NewCursorY+1,0,0));
   end;
  CursorX:=NewCursorX+1;
  CursorY:=NewCursorY+1;
end;


function SysGetCursorType: Word;
begin
  SysGetCursorType:=LastCursorType;
end;


procedure SysSetCursorType(NewType: Word);
begin
  LastCursorType:=NewType;
  case NewType of
   crBlock :
     Begin
       If not SendEscapeSeqNdx(cursor_visible) then
         SendEscapeSeq(#27'[?17;0;64c');
     End;
   crHidden :
     Begin
       If not SendEscapeSeqNdx(cursor_invisible) then
         SendEscapeSeq(#27'[?1c');
     End;
  else
    begin
      If not SendEscapeSeqNdx(cursor_normal) then
        SendEscapeSeq(#27'[?2c');
    end;
  end;
end;

Const
  SysVideoDriver : TVideoDriver = (
    InitDriver : @SysInitVideo;
    DoneDriver : @SysDoneVideo;
    UpdateScreen : @SysUpdateScreen;
    ClearScreen : @SysClearScreen;
    SetVideoMode : Nil;
    GetVideoModeCount : Nil;
    GetVideoModeData : Nil;
    SetCursorPos : @SysSetCursorPos;
    GetCursorType : @SysGetCursorType;
    SetCursorType : @SysSetCursorType;
    GetCapabilities : @SysGetCapabilities;
  );

initialization
  SetVideoDriver(SysVideoDriver);
end.
{
  $Log$
  Revision 1.12  2002-09-07 16:01:28  peter
    * old logs removed and tabs fixed

  Revision 1.11  2002/07/06 16:50:17  marco
   * Fix for corrupt color-attr after some ACS-mode changes. (Pierre, Strassbourg
      meeting)

}