{
    This file is part of the Free Pascal run time library.
    Copyright (c) 2020 by Karoly Balogh

    System unit for the Sinclair QL

    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 System;

interface

{$define FPC_IS_SYSTEM}
{$define FPC_STDOUT_TRUE_ALIAS}
{$define FPC_ANSI_TEXTFILEREC}
{$define FPC_QL_USE_OSHEAP}

{$ifdef FPC_QL_USE_OSHEAP}
{$define HAS_MEMORYMANAGER}
{$endif FPC_QL_USE_OSHEAP}

{$i systemh.inc}

{Platform specific information}
const
    LineEnding = #10;
    LFNSupport = false;
    CtrlZMarksEOF: boolean = false; (* #26 not considered as end of file *)
    DirectorySeparator = '\';
    DriveSeparator = ':';
    ExtensionSeparator = '.';
    PathSeparator = ';';
    AllowDirectorySeparators : set of char = ['\','/'];
    AllowDriveSeparators : set of char = [':'];
    FileNameCaseSensitive = false;
    FileNameCasePreserving = false;
    maxExitCode = 255;
    MaxPathLen = 255;
    AllFilesMask = '*.*';

    sLineBreak = LineEnding;
    DefaultTextLineBreakStyle : TTextLineBreakStyle = tlbsLF;

const
    UnusedHandle    = -1;
    StdInputHandle: longint = UnusedHandle;
    StdOutputHandle: longint = UnusedHandle;
    StdErrorHandle: longint = UnusedHandle;

var
    QL_ChannelIDNum : word;
    QL_ChannelIDs: pdword;
    QL_CommandLineLen : word;
    QL_CommandLine : pchar;

    argv: PPChar;
    argc: Longint;

    {$if defined(FPUSOFT)}

    {$define fpc_softfpu_interface}
    {$i softfpu.pp}
    {$undef fpc_softfpu_interface}

    {$endif defined(FPUSOFT)}

type
  QLConHandle = record
    inputHandle: longint;
    outputHandle: longint;
    errorHandle: longint;
    userData: pointer;
  end;



function SetQLJobName(const s: string): longint;
function GetQLJobName: string;
function GetQLJobNamePtr: pointer;

procedure SetQLDefaultConExitMessage(const msg: PChar);

implementation

  {$define FPC_SYSTEM_HAS_STACKTOP}
  {$define FPC_SYSTEM_HAS_BACKTRACESTR}

  {$if defined(FPUSOFT)}

  {$define fpc_softfpu_implementation}
  {$define softfpu_compiler_mul32to64}
  {$define softfpu_inline}
  {$i softfpu.pp}
  {$undef fpc_softfpu_implementation}

  { we get these functions and types from the softfpu code }
  {$define FPC_SYSTEM_HAS_float64}
  {$define FPC_SYSTEM_HAS_float32}
  {$define FPC_SYSTEM_HAS_flag}
  {$define FPC_SYSTEM_HAS_extractFloat64Frac0}
  {$define FPC_SYSTEM_HAS_extractFloat64Frac1}
  {$define FPC_SYSTEM_HAS_extractFloat64Exp}
  {$define FPC_SYSTEM_HAS_extractFloat64Sign}
  {$define FPC_SYSTEM_HAS_ExtractFloat32Frac}
  {$define FPC_SYSTEM_HAS_extractFloat32Exp}
  {$define FPC_SYSTEM_HAS_extractFloat32Sign}

  {$endif defined(FPUSOFT)}

  {$i system.inc}
  {$ifdef FPC_QL_USE_OSHEAP}
  {$i osheap.inc}
  {$endif FPC_QL_USE_OSHEAP}


function GetProcessID:SizeUInt;
begin
  GetProcessID := mt_inf(nil, nil);
end;

{*****************************************************************************
                             ParamStr
*****************************************************************************}

var
  args: PChar;

{ number of args }
function ParamCount: LongInt;
begin
  ParamCount:=argc;
end;

{ argument number l }
function ParamStr(l: LongInt): string;
begin
  if (l >= 0) and (l <= argc) then
    ParamStr:=argv[l]
  else
    ParamStr:='';
end;

procedure SysInitParamsAndEnv;
var
  i,j : longint;
  c : char;
  argv_size : longint;
const
  word_separators=[' ',#0];
begin
  argc:=0;
  argv:=nil;
  args:=GetMem(QL_CommandLineLen+1);
  if not assigned(args) then
    exit;

  Move(QL_CommandLine^,args^,QL_CommandLineLen);
  args[QL_CommandLineLen]:=#0;

  i:=0;
  c:=' ';
  while args[i]<>#0 do
    begin
      if (c in word_separators) and not (args[i] in word_separators) then
        inc(argc);
      c:=args[i];
      inc(i);
    end;

  { +2 is because argv[0] should be program name, 
    and argv[argc+1] is argv array terminator }
  argv:=GetMem((argc+2)*sizeof(pointer));
  if not assigned(argv) then
    begin
      argc:=0;
      exit;
    end;
  argv[argc+1]:=nil;
  { FIX ME: for now the 0th argument (program name) is just always empty }
  argv[0]:=#0;

  i:=0;
  j:=1;
  c:=' ';
  while args[i]<>#0 do
    begin
      if (c in word_separators) and not (args[i] in word_separators) then
        begin
          argv[j]:=@args[i];
          inc(j);
        end;
      c:=args[i];
      if (c in word_separators) then
        args[i]:=#0;
      inc(i);
    end;
end;

procedure randomize;
begin
  { Get the current date/time }
  randseed:=mt_rclck;
end;


{*****************************************************************************
                      Platform specific custom calls
*****************************************************************************}

procedure PrintStr(ch: longint; const s: shortstring);
begin
  io_sstrg(ch,-1,@s[1],ord(s[0]));
end;

procedure DebugStr(const s: shortstring); public name '_dbgstr';
var
  i: longint;
begin
  PrintStr(stdOutputHandle,s);
  for i:=0 to 10000 do begin end;
end;


var
  start_proc: byte; external name '_start'; 

  { WARNING! if you change this value, make sure there's enough
    buffer space for the job name in the startup code! }
const
  JOB_NAME_MAX_LEN = 48;

function SetQLJobName(const s: string): longint;
var
  len: longint;
begin
  SetQLJobName:=-1;
  if pword(@start_proc)[3] = $4afb then
    begin
      len:=length(s);
      if len > JOB_NAME_MAX_LEN then
        len:=JOB_NAME_MAX_LEN;
      Move(s[1],pword(@start_proc)[5],len);
      pword(@start_proc)[4]:=len;
      SetQLJobName:=len;
    end;
end;

function GetQLJobName: string;
var
  len: longint;
begin
  GetQLJobName:='';
  if pword(@start_proc)[3] = $4afb then
    begin
      len:=pword(@start_proc)[4];
      if len <= JOB_NAME_MAX_LEN then
        begin
          SetLength(GetQLJobName,len);
          Move(pword(@start_proc)[5],GetQLJobName[1],len);
        end;
    end;
end;

function GetQLJobNamePtr: pointer;
begin
  GetQLJobNamePtr:=nil;
  if pword(@start_proc)[3] = $4afb then
    begin
      GetQLJobNamePtr:=@pword(@start_proc)[4];
    end;
end;

const
  QLDefaultConExitMessage: PChar = 'Press any key to exit';

procedure SetQLDefaultConExitMessage(const msg: PChar);
begin
  QLDefaultConExitMessage:=msg;
end;


function QLOpenCon(var console: QLConHandle): boolean; weakexternal name 'QLOpenCon';
procedure QLCloseCon(var console: QLConHandle); weakexternal name 'QLCloseCon';

function DefaultQLOpenCon(var console: QLConHandle): boolean;
var
  r: TQLRect;
begin
  DefaultQLOpenCon:=false;
  with console do
    begin
      inputHandle:=io_open('con_',Q_OPEN);
      if inputHandle <= 0 then
        exit;

      outputHandle:=inputHandle;
      errorHandle:=inputHandle;
      userData:=nil;

      r.q_width:=512;
      r.q_height:=256;
      r.q_x:=0;
      r.q_y:=0;

      sd_wdef(outputHandle,-1,2,1,@r);
      sd_clear(outputHandle,-1);
    end;
  DefaultQLOpenCon:=true;
end;

procedure DefaultQLCloseCon(var console: QLConHandle);
begin
  with console do
    begin
      if assigned(QLDefaultConExitMessage) and (length(QLDefaultConExitMessage) > 0) then
        begin
          io_sstrg(outputHandle, -1, QLDefaultConExitMessage, length(QLDefaultConExitMessage));
          io_fbyte(inputHandle, -1);
        end;
    end;
end;

{*****************************************************************************
                        System Dependent Entry code
*****************************************************************************}
var
  jobStackDataPtr: pointer; external name '__stackpointer_on_entry';
  program_name: shortstring; external name '__fpc_program_name';
  QLCon: QLConHandle;
  QLConOpen: boolean;

{ QL/QDOS specific startup }
procedure SysInitQDOS;
begin
  QL_ChannelIDNum:=pword(jobStackDataPtr)[0];
  QL_ChannelIDs:=@pword(jobStackDataPtr)[1];
  QL_CommandLineLen:=pword(@QL_ChannelIDs[QL_ChannelIDNum])[0];
  QL_CommandLine:=@pword(@QL_ChannelIDs[QL_ChannelIDNum])[1];

  SetQLJobName(program_name);

  if assigned(@QLOpenCon) then
    QLConOpen:=QLOpenCon(QLCon)
  else
    QLConOpen:=DefaultQLOpenCon(QLCon);
  if not QLConOpen then
    halt(1);

  with QLCon do
    begin
      stdInputHandle:=inputHandle;
      stdOutputHandle:=outputHandle;
      stdErrorHandle:=errorHandle;
    end;
end;

{*****************************************************************************
                         System Dependent Exit code
*****************************************************************************}

procedure haltproc(e:longint); external name '_haltproc';

procedure system_exit;
begin
  if assigned(args) then
    FreeMem(args);
  if assigned(argv) then
    FreeMem(argv);

  if QLConOpen then
    begin
      if assigned(@QLCloseCon) then
        QLCloseCon(QLCon)
      else
        DefaultQLCloseCon(QLCon);
    end;

  stdInputHandle:=UnusedHandle;
  stdOutputHandle:=UnusedHandle;
  stdErrorHandle:=UnusedHandle;
  haltproc(exitcode);
end;

{*****************************************************************************
                         System Unit Initialization
*****************************************************************************}

procedure SysInitStdIO;
begin
  OpenStdIO(Input,fmInput,StdInputHandle);
  OpenStdIO(Output,fmOutput,StdOutputHandle);
  OpenStdIO(ErrOutput,fmOutput,StdErrorHandle);
{$ifndef FPC_STDOUT_TRUE_ALIAS}
  OpenStdIO(StdOut,fmOutput,StdOutputHandle);
  OpenStdIO(StdErr,fmOutput,StdErrorHandle);
{$endif FPC_STDOUT_TRUE_ALIAS}
end;

function CheckInitialStkLen (StkLen: SizeUInt): SizeUInt;
begin
  CheckInitialStkLen := StkLen;
end;


begin
  StackLength := CheckInitialStkLen (InitialStkLen);
  StackBottom := StackTop - StackLength;
  StackMargin := min(align(StackLength div 20,2),STACK_MARGIN_MAX);
{ Initialize ExitProc }
  ExitProc:=Nil;
  SysInitQDOS;
{$ifndef FPC_QL_USE_OSHEAP}
{ Setup heap }
  InitHeap;
{$else FPC_QL_USE_OSHEAP}
//  InitOSHeap;
{$endif FPC_QL_USE_OSHEAP}
  SysInitExceptions;
{$ifdef FPC_HAS_FEATURE_UNICODESTRINGS}
  InitUnicodeStringManager;
{$endif FPC_HAS_FEATURE_UNICODESTRINGS}
{ Setup stdin, stdout and stderr }
  SysInitStdIO;
{ Reset IO Error }
  InOutRes:=0;
{ Setup command line arguments }
  SysInitParamsAndEnv;
{$ifdef FPC_HAS_FEATURE_THREADING}
  InitSystemThreads;
{$endif FPC_HAS_FEATURE_THREADING}
end.