(*
    Copyright 2016, 2019, 2021-2023 Anton Krotov

    This file is part of fb2read.

    fb2read 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, either version 3 of the License, or
    (at your option) any later version.

    fb2read 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 fb2read. If not, see <http://www.gnu.org/licenses/>.
*)

MODULE SysUtils;

IMPORT K := KOSAPI, sys := SYSTEM, S := Strings;


CONST

  L_BUTTON* = 0;

  FontH* = 16;
  FontW* =  8;


TYPE

  ENTRY* = PROCEDURE;


VAR
	(*darkColor*,*) lightColor*,
    winColor*, textColor*, btnColor*, btnTextColor*,
    borderColor*: INTEGER;


PROCEDURE GetParam*(VAR Param: S.STRING);
VAR
  adr    : INTEGER;
  c      : CHAR;
  i, max : INTEGER;
BEGIN
  adr := K.GetCommandLine();
  i := 0;
  max := LEN(Param) - 1;
  REPEAT
    sys.GET(adr, c);
    INC(adr);
    Param[i] := c;
    INC(i)
  UNTIL (c = 0X) OR (i = max);
  Param[i] := 0X;
  S.Trim(Param, 20X);
  S.Trim(Param, 22X)
END GetParam;


PROCEDURE Halt*;
BEGIN
    K.sysfunc1(-1)
END Halt;


PROCEDURE Run*(program: S.STRING; param: INTEGER);
TYPE

  info_struct = RECORD
    subfunc : INTEGER;
    flags   : INTEGER;
    param   : INTEGER;
    rsrvd1  : INTEGER;
    rsrvd2  : INTEGER;
    fname   : ARRAY 1024 OF CHAR
  END;

VAR
  info: info_struct;

BEGIN
  info.subfunc := 7;
  info.flags   := 0;
  info.param   := param;
  info.rsrvd1  := 0;
  info.rsrvd2  := 0;
  COPY(program, info.fname);
  K.sysfunc2(70, sys.ADR(info))
END Run;


PROCEDURE ErrorIf*(condition: BOOLEAN; code: INTEGER);
VAR str, str2: S.STRING;
BEGIN
  IF condition THEN
    str := "'FB2 ERROR: ";
    S.IntToString(code, str2);
    S.Append(str, str2);
    S.Append(str, "' -E");
    Run("/sys/@notify", sys.ADR(str[0]));
    Halt
  END
END ErrorIf;


PROCEDURE MemError*(err: BOOLEAN);
BEGIN
  ErrorIf(err, 13)
END MemError;


PROCEDURE MinMax*(VAR value: INTEGER; min, max: INTEGER);
BEGIN
  value := MIN(MAX(value, min), max)
END MinMax;


PROCEDURE MousePos*(VAR X, Y: INTEGER);
VAR res: INTEGER;
BEGIN
  res := K.sysfunc2(37, 0);
  X := LSR(res, 16);
  Y := ORD(BITS(res) * {0..15});
END MousePos;


PROCEDURE MouseVScroll*(): INTEGER;
	RETURN ASR(LSL(K.sysfunc2(37, 7), 16), 16)
END MouseVScroll;


PROCEDURE MouseStatus*(): SET;
  RETURN BITS(K.sysfunc2(37, 3))
END MouseStatus;


PROCEDURE WindowRedrawStatus*(status: INTEGER);
BEGIN
    K.sysfunc2(12, status)
END WindowRedrawStatus;


PROCEDURE DefineAndDrawWindow*(Left, Top, Width, Height, Color, Style: INTEGER; Caption: ARRAY OF CHAR);
BEGIN
    K.sysfunc6(0, LSL(Left, 16) + Width, LSL(Top, 16) + Height, Color + LSL(Style, 24), 0, sys.ADR(Caption[0]))
END DefineAndDrawWindow;


PROCEDURE WaitForEvent*(): INTEGER;
  RETURN K.sysfunc1(10)
END WaitForEvent;


PROCEDURE CheckEvent*(): INTEGER;
  RETURN K.sysfunc1(11)
END CheckEvent;


PROCEDURE SetEventsMask*(mask: SET);
BEGIN
    K.sysfunc2(40, ORD(mask))
END SetEventsMask;


PROCEDURE GetKey* (): INTEGER;
    RETURN K.sysfunc1(2)
END GetKey;


PROCEDURE GetControlKeys* (): SET;
    RETURN BITS(K.sysfunc2(66, 3))
END GetControlKeys;


PROCEDURE getKBState* (VAR shift, ctrl: BOOLEAN);
VAR
    kbState: SET;
BEGIN
    kbState := GetControlKeys();
    shift := {0, 1} * kbState # {};
    ctrl := {2, 3} * kbState # {};
END getKBState;


PROCEDURE GetButtonCode*(): INTEGER;
VAR res, button_code: INTEGER;
BEGIN
  res := K.sysfunc1(17);
  IF ORD(BITS(res) * {0..7}) = 0 THEN
    button_code := LSR(res, 8)
  ELSE
    button_code := 0
  END
  RETURN button_code
END GetButtonCode;


PROCEDURE OutText*(X, Y: INTEGER; Text: ARRAY OF CHAR; length: INTEGER; color: INTEGER);
BEGIN
    K.sysfunc6(4, LSL(X, 16) + Y, LSL(3 * 16, 24) + color, sys.ADR(Text[0]), length, 0)
END OutText;


PROCEDURE GetWindowPos*(VAR Left, Top: INTEGER);
VAR info: ARRAY 1024 OF CHAR;
BEGIN
  K.sysfunc3(9, sys.ADR(info[0]), -1);
  sys.GET(sys.ADR(info[34]), Left);
  sys.GET(sys.ADR(info[38]), Top)
END GetWindowPos;


PROCEDURE GetWindowSize*(VAR Width, Height: INTEGER);
VAR info: ARRAY 1024 OF CHAR;
BEGIN
  K.sysfunc3(9, sys.ADR(info[0]), -1);
  sys.GET(sys.ADR(info[42]), Width);
  sys.GET(sys.ADR(info[46]), Height)
END GetWindowSize;


PROCEDURE SetWindowSize*(Width, Height: INTEGER);
BEGIN
    K.sysfunc5(67, -1, -1, Width, Height)
END SetWindowSize;


PROCEDURE GetScreenSize*(VAR Width, Height: INTEGER);
VAR res: INTEGER;
BEGIN
  res := K.sysfunc1(14);
  Width := LSR(res, 16) + 1;
  Height := ORD(BITS(res) * {0..15}) + 1
END GetScreenSize;


PROCEDURE GetScreenArea*(VAR X1, Y1, X2, Y2: INTEGER);
VAR eax, ebx: INTEGER;
BEGIN
  eax := K.sysfunc22(48, 5, ebx);
  X1 := LSR(eax, 16);
  Y1 := LSR(ebx, 16);
  X2 := ORD(BITS(eax) * {0..15});
  Y2 := ORD(BITS(ebx) * {0..15})
END GetScreenArea;


PROCEDURE SkinHeight*(): INTEGER;
  RETURN K.sysfunc2(48, 4)
END SkinHeight;


PROCEDURE DrawRect*(Left, Top, Width, Height, Color: INTEGER);
BEGIN
    K.sysfunc4(13, LSL(Left, 16) + Width, LSL(Top, 16) + Height, Color)
END DrawRect;


PROCEDURE NewThread*(eip: ENTRY; stack: ARRAY OF CHAR): INTEGER;
VAR entry: INTEGER;
BEGIN
  sys.GET(sys.ADR(eip), entry)
  RETURN K.sysfunc4(51, 1, entry, sys.ADR(stack[0]) + LEN(stack))
END NewThread;


PROCEDURE Pause*(time: INTEGER);
BEGIN
    K.sysfunc2(5, time)
END Pause;


PROCEDURE GetThreadSlot*(PID: INTEGER): INTEGER;
  RETURN K.sysfunc3(18, 21, PID)
END GetThreadSlot;


PROCEDURE TerminateThreadId*(PID: INTEGER);
BEGIN
    K.sysfunc3(18, 18, PID)
END TerminateThreadId;


PROCEDURE IsTerminated*(PID: INTEGER): BOOLEAN;
  RETURN GetThreadSlot(PID) = 0
END IsTerminated;


PROCEDURE FocusWindow*(Slot: INTEGER);
BEGIN
    K.sysfunc3(18, 3, Slot)
END FocusWindow;


PROCEDURE CreateButton*(id, Left, Top, Width, Height, Color: INTEGER; Caption: ARRAY OF CHAR);
VAR
  X, Y, len: INTEGER;

BEGIN
  len := LENGTH(Caption);
  K.sysfunc5(8, LSL(Left, 16) + Width, LSL(Top, 16) + Height, id, btnColor);
  X := Left + (Width - FontW * len) DIV 2;
  Y := Top + (Height - FontH) DIV 2 + 1;
  OutText(X, Y, Caption, len, btnTextColor)
END CreateButton;


PROCEDURE DrawLine* (x1, y1, x2, y2: INTEGER; color: INTEGER);
BEGIN
	K.sysfunc4(38, x1*65536 + x2, y1*65536 + y2, color)
END DrawLine;


PROCEDURE Box*(Left, Top, Width, Height, BrushColor, PenColor: INTEGER);
BEGIN
  K.sysfunc4(13, LSL(Left, 16) + Width, LSL(Top, 16) + Height, BrushColor);
  DrawLine(Left, Top, Left + Width, Top, PenColor);
  DrawLine(Left + Width, Top, Left + Width, Top + Height, PenColor);
  DrawLine(Left + Width, Top + Height, Left, Top + Height, PenColor);
  DrawLine(Left, Top + Height, Left, Top, PenColor);
END Box;


PROCEDURE LoadCursor*(cursor: INTEGER): INTEGER;
  RETURN K.sysfunc4(37, 4, cursor, 1)
END LoadCursor;


PROCEDURE SetCursor*(handle: INTEGER);
BEGIN
    K.sysfunc3(37, 5, handle)
END SetCursor;


PROCEDURE DelCursor*(handle: INTEGER);
BEGIN
    K.sysfunc3(37, 6, handle)
END DelCursor;


PROCEDURE DrawImage* (data, sizeX, sizeY, x, y: INTEGER);
BEGIN
    K.sysfunc4(7, data, sizeX*65536 + sizeY, x*65536 + y)
END DrawImage;


PROCEDURE DrawText69* (x, y, color: INTEGER; text: ARRAY OF CHAR);
BEGIN
    K.sysfunc6(4, x*65536 + y, color + LSL(080H, 24), sys.ADR(text[0]), 0, 0)
END DrawText69;


PROCEDURE PutPixel* (x, y, color: INTEGER);
BEGIN
	K.sysfunc5(1, x, y, color, 0)
END PutPixel;


PROCEDURE GetSystemColors*;
VAR
    buf: ARRAY 10 OF INTEGER;
BEGIN
    ASSERT(LEN(buf) >= 10);
    K.sysfunc4(48, 3, sys.ADR(buf[0]), 40);
	(*darkColor := buf[2];*)
	lightColor := buf[3];
    winColor := buf[5];
    textColor := buf[8];
    btnColor := buf[6];
    btnTextColor := buf[7];
    borderColor := buf[9];
END GetSystemColors;


PROCEDURE RolledUp* (): BOOLEAN;
VAR
	buffer: ARRAY 1024 OF BYTE;
BEGIN
	K.sysfunc3(9, sys.ADR(buffer[0]), -1)
	RETURN ODD(LSR(buffer[70], 2))
END RolledUp;


END SysUtils.