{*******************************************************}
{                                                       }
{       Turbo Pascal Version 6.0                        }
{       Turbo Vision Unit                               }
{                                                       }
{       Copyright (c) 1990 Borland International        }
{                                                       }
{*******************************************************}

unit Views;

{$F+,O+,S-,X+}

interface

uses Objects, Drivers, Memory;

const

{ TView State masks }

  sfVisible     = $0001;
  sfCursorVis   = $0002;
  sfCursorIns   = $0004;
  sfShadow      = $0008;
  sfActive      = $0010;
  sfSelected    = $0020;
  sfFocused     = $0040;
  sfDragging    = $0080;
  sfDisabled    = $0100;
  sfModal       = $0200;
  sfDefault     = $0400;
  sfExposed     = $0800;

{ TView Option masks }

  ofSelectable  = $0001;
  ofTopSelect   = $0002;
  ofFirstClick  = $0004;
  ofFramed      = $0008;
  ofPreProcess  = $0010;
  ofPostProcess = $0020;
  ofBuffered    = $0040;
  ofTileable    = $0080;
  ofCenterX     = $0100;
  ofCenterY     = $0200;
  ofCentered    = $0300;

{ TView GrowMode masks }

  gfGrowLoX = $01;
  gfGrowLoY = $02;
  gfGrowHiX = $04;
  gfGrowHiY = $08;
  gfGrowAll = $0F;
  gfGrowRel = $10;

{ TView DragMode masks }

  dmDragMove = $01;
  dmDragGrow = $02;
  dmLimitLoX = $10;
  dmLimitLoY = $20;
  dmLimitHiX = $40;
  dmLimitHiY = $80;
  dmLimitAll = $F0;

{ TView Help context codes }

  hcNoContext = 0;
  hcDragging  = 1;

{ TScrollBar part codes }

  sbLeftArrow  = 0;
  sbRightArrow = 1;
  sbPageLeft   = 2;
  sbPageRight  = 3;
  sbUpArrow    = 4;
  sbDownArrow  = 5;
  sbPageUp     = 6;
  sbPageDown   = 7;
  sbIndicator  = 8;

{ TScrollBar options for TWindow.StandardScrollBar }

  sbHorizontal     = $0000;
  sbVertical       = $0001;
  sbHandleKeyboard = $0002;

{ TWindow Flags masks }

  wfMove  = $01;
  wfGrow  = $02;
  wfClose = $04;
  wfZoom  = $08;

{ TWindow number constants }

  wnNoNumber = 0;

{ TWindow palette entries }

  wpBlueWindow = 0;
  wpCyanWindow = 1;
  wpGrayWindow = 2;

{ Standard command codes }

  cmValid   = 0;
  cmQuit    = 1;
  cmError   = 2;
  cmMenu    = 3;
  cmClose   = 4;
  cmZoom    = 5;
  cmResize  = 6;
  cmNext    = 7;
  cmPrev    = 8;
  cmHelp    = 9;

{ Application command codes }

  cmCut     = 20;
  cmCopy    = 21;
  cmPaste   = 22;
  cmUndo    = 23;
  cmClear   = 24;
  cmTile    = 25;
  cmCascade = 26;

{ TDialog standard commands }

  cmOK      = 10;
  cmCancel  = 11;
  cmYes     = 12;
  cmNo      = 13;
  cmDefault = 14;

{ Standard messages }

  cmReceivedFocus     = 50;
  cmReleasedFocus     = 51;
  cmCommandSetChanged = 52;

{ TScrollBar messages }

  cmScrollBarChanged  = 53;
  cmScrollBarClicked  = 54;

{ TWindow select messages }

  cmSelectWindowNum   = 55;

{ TListViewer messages }

  cmListItemSelected  = 56;

{ Color palettes }

  CFrame      = #1#1#2#2#3;
  CScrollBar  = #4#5#5;
  CScroller   = #6#7;
  CListViewer = #26#26#27#28#29;
  CBlueWindow = #8#9#10#11#12#13#14#15;
  CCyanWindow = #16#17#18#19#20#21#22#23;
  CGrayWindow = #24#25#26#27#28#29#30#31;

{ TDrawBuffer maximum view width }

  MaxViewWidth = 132;

type

{ Command sets }

  PCommandSet = ^TCommandSet;
  TCommandSet = set of Byte;

{ Color palette type }

  PPalette = ^TPalette;
  TPalette = String;

{ TDrawBuffer, buffer used by draw methods }

  TDrawBuffer = array[0..MaxViewWidth - 1] of Word;

{ TView object Pointer }

  PView = ^TView;

{ TGroup object Pointer }

  PGroup = ^TGroup;

{ TView object }

  TView = object(TObject)
    Owner: PGroup;
    Next: PView;
    Origin: TPoint;
    Size: TPoint;
    Cursor: TPoint;
    GrowMode: Byte;
    DragMode: Byte;
    HelpCtx: Word;
    State: Word;
    Options: Word;
    EventMask: Word;
    constructor Init(var Bounds: TRect);
    constructor Load(var S: TStream);
    destructor Done; virtual;
    procedure BlockCursor;
    procedure CalcBounds(var Bounds: TRect; Delta: TPoint); virtual;
    procedure ChangeBounds(var Bounds: TRect); virtual;
    procedure ClearEvent(var Event: TEvent);
    function CommandEnabled(Command: Word): Boolean;
    function DataSize: Word; virtual;
    procedure DisableCommands(Commands: TCommandSet);
    procedure DragView(Event: TEvent; Mode: Byte;
      var Limits: TRect; MinSize, MaxSize: TPoint);
    procedure Draw; virtual;
    procedure DrawView;
    procedure EnableCommands(Commands: TCommandSet);
    procedure EndModal(Command: Word); virtual;
    function EventAvail: Boolean;
    function Execute: Word; virtual;
    function Exposed: Boolean;
    procedure GetBounds(var Bounds: TRect);
    procedure GetClipRect(var Clip: TRect);
    function GetColor(Color: Word): Word;
    procedure GetCommands(var Commands: TCommandSet);
    procedure GetData(var Rec); virtual;
    procedure GetEvent(var Event: TEvent); virtual;
    procedure GetExtent(var Extent: TRect);
    function GetHelpCtx: Word; virtual;
    function GetPalette: PPalette; virtual;
    procedure GetPeerViewPtr(var S: TStream; var P);
    function GetState(AState: Word): Boolean;
    procedure GrowTo(X, Y: Integer);
    procedure HandleEvent(var Event: TEvent); virtual;
    procedure Hide;
    procedure HideCursor;
    procedure KeyEvent(var Event: TEvent);
    procedure Locate(var Bounds: TRect);
    procedure MakeFirst;
    procedure MakeGlobal(Source: TPoint; var Dest: TPoint);
    procedure MakeLocal(Source: TPoint; var Dest: TPoint);
    function MouseEvent(var Event: TEvent; Mask: Word): Boolean;
    function MouseInView(Mouse: TPoint): Boolean;
    procedure MoveTo(X, Y: Integer);
    function NextView: PView;
    procedure NormalCursor;
    function Prev: PView;
    function PrevView: PView;
    procedure PutEvent(var Event: TEvent); virtual;
    procedure PutInFrontOf(Target: PView);
    procedure PutPeerViewPtr(var S: TStream; P: PView);
    procedure Select;
    procedure SetBounds(var Bounds: TRect);
    procedure SetCommands(Commands: TCommandSet);
    procedure SetCursor(X, Y: Integer);
    procedure SetData(var Rec); virtual;
    procedure SetState(AState: Word; Enable: Boolean); virtual;
    procedure Show;
    procedure ShowCursor;
    procedure SizeLimits(var Min, Max: TPoint); virtual;
    procedure Store(var S: TStream);
    function TopView: PView;
    function Valid(Command: Word): Boolean; virtual;
    procedure WriteBuf(X, Y, W, H: Integer; var Buf);
    procedure WriteChar(X, Y: Integer; C: Char; Color: Byte;
      Count: Integer);
    procedure WriteLine(X, Y, W, H: Integer; var Buf);
    procedure WriteStr(X, Y: Integer; Str: String; Color: Byte);
  end;

{ TFrame types }

  TTitleStr = string[80];

{ TFrame object }

  { Palette layout }
  { 1 = Passive frame }
  { 2 = Passive title }
  { 3 = Active frame }
  { 4 = Active title }
  { 5 = Icons }

  PFrame = ^TFrame;
  TFrame = object(TView)
    constructor Init(var Bounds: TRect);
    procedure Draw; virtual;
    function GetPalette: PPalette; virtual;
    procedure HandleEvent(var Event: TEvent); virtual;
    procedure SetState(AState: Word; Enable: Boolean); virtual;
  end;

{ ScrollBar characters }

  TScrollChars = array[0..4] of Char;

{ TScrollBar object }

  { Palette layout }
  { 1 = Page areas }
  { 2 = Arrows }
  { 3 = Indicator }

  PScrollBar = ^TScrollBar;
  TScrollBar = object(TView)
    Value: Integer;
    Min: Integer;
    Max: Integer;
    PgStep: Integer;
    ArStep: Integer;
    constructor Init(var Bounds: TRect);
    constructor Load(var S: TStream);
    procedure Draw; virtual;
    function GetPalette: PPalette; virtual;
    procedure HandleEvent(var Event: TEvent); virtual;
    procedure ScrollDraw; virtual;
    function ScrollStep(Part: Integer): Integer; virtual;
    procedure SetParams(AValue, AMin, AMax, APgStep, AArStep: Integer);
    procedure SetRange(AMin, AMax: Integer);
    procedure SetStep(APgStep, AArStep: Integer);
    procedure SetValue(AValue: Integer);
    procedure Store(var S: TStream);
  end;

{ TScroller object }

  { Palette layout }
  { 1 = Normal text }
  { 2 = Selected text }

  PScroller = ^TScroller;
  TScroller = object(TView)
    HScrollBar: PScrollBar;
    VScrollBar: PScrollBar;
    Delta: TPoint;
    Limit: TPoint;
    constructor Init(var Bounds: TRect; AHScrollBar, AVScrollBar: PScrollBar);
    constructor Load(var S: TStream);
    procedure ChangeBounds(var Bounds: TRect); virtual;
    function GetPalette: PPalette; virtual;
    procedure HandleEvent(var Event: TEvent); virtual;
    procedure ScrollDraw; virtual;
    procedure ScrollTo(X, Y: Integer);
    procedure SetLimit(X, Y: Integer);
    procedure SetState(AState: Word; Enable: Boolean); virtual;
    procedure Store(var S: TStream);
  end;

{ TListViewer }

  { Palette layout }
  { 1 = Active }
  { 2 = Inactive }
  { 3 = Focused }
  { 4 = Selected }
  { 5 = Divider }

  PListViewer = ^TListViewer;

  TListViewer = object(TView)
    HScrollBar: PScrollBar;
    VScrollBar: PScrollBar;
    NumCols: Integer;
    TopItem: Integer;
    Focused: Integer;
    Range: Integer;
    constructor Init(var Bounds: TRect; ANumCols: Word;
      AHScrollBar, AVScrollBar: PScrollBar);
    constructor Load(var S: TStream);
    procedure ChangeBounds(var Bounds: TRect); virtual;
    procedure Draw; virtual;
    procedure FocusItem(Item: Integer); virtual;
    function GetPalette: PPalette; virtual;
    function GetText(Item: Integer; MaxLen: Integer): String; virtual;
    function IsSelected(Item: Integer): Boolean; virtual;
    procedure HandleEvent(var Event: TEvent); virtual;
    procedure SelectItem(Item: Integer); virtual;
    procedure SetRange(ARange: Integer);
    procedure SetState(AState: Word; Enable: Boolean); virtual;
    procedure Store(var S: TStream);
  end;

{ Video buffer }

  PVideoBuf = ^TVideoBuf;
  TVideoBuf = array[0..3999] of Word;

{ Selection modes }

  SelectMode = (NormalSelect, EnterSelect, LeaveSelect);

{ TGroup object }

  TGroup = object(TView)
    Last: PView;
    Current: PView;
    Phase: (phFocused, phPreProcess, phPostProcess);
    Buffer: PVideoBuf;
    constructor Init(var Bounds: TRect);
    constructor Load(var S: TStream);
    destructor Done; virtual;
    procedure ChangeBounds(var Bounds: TRect); virtual;
    function DataSize: Word; virtual;
    procedure Delete(P: PView);
    procedure Draw; virtual;
    procedure EndModal(Command: Word); virtual;
    procedure EventError(var Event: TEvent); virtual;
    function ExecView(P: PView): Word;
    function Execute: Word; virtual;
    function First: PView;
    function FirstThat(P: Pointer): PView;
    procedure ForEach(P: Pointer);
    procedure GetData(var Rec); virtual;
    function GetHelpCtx: Word; virtual;
    procedure GetSubViewPtr(var S: TStream; var P);
    procedure HandleEvent(var Event: TEvent); virtual;
    procedure Insert(P: PView);
    procedure InsertBefore(P, Target: PView);
    procedure Lock;
    procedure PutSubViewPtr(var S: TStream; P: PView);
    procedure Redraw;
    procedure SelectNext(Forwards: Boolean);
    procedure SetData(var Rec); virtual;
    procedure SetState(AState: Word; Enable: Boolean); virtual;
    procedure Store(var S: TStream);
    procedure Unlock;
    function Valid(Command: Word): Boolean; virtual;
  end;

{ TWindow object }

  { Palette layout }
  { 1 = Frame passive }
  { 2 = Frame active }
  { 3 = Frame icon }
  { 4 = ScrollBar page area }
  { 5 = ScrollBar controls }
  { 6 = Scroller normal text }
  { 7 = Scroller selected text }
  { 8 = Reserved }

  PWindow = ^TWindow;
  TWindow = object(TGroup)
    Flags: Byte;
    ZoomRect: TRect;
    Number: Integer;
    Palette: Integer;
    Frame: PFrame;
    Title: PString;
    constructor Init(var Bounds: TRect; ATitle: TTitleStr; ANumber: Integer);
    constructor Load(var S: TStream);
    destructor Done; virtual;
    procedure Close; virtual;
    function GetPalette: PPalette; virtual;
    function GetTitle(MaxSize: Integer): TTitleStr; virtual;
    procedure HandleEvent(var Event: TEvent); virtual;
    procedure InitFrame; virtual;
    procedure SetState(AState: Word; Enable: Boolean); virtual;
    procedure SizeLimits(var Min, Max: TPoint); virtual;
    function StandardScrollBar(AOptions: Word): PScrollBar;
    procedure Store(var S: TStream);
    procedure Zoom; virtual;
  end;

{ Message dispatch function }

function Message(Receiver: PView; What, Command: Word;
  InfoPtr: Pointer): Pointer;

{ Views registration procedure }

procedure RegisterViews;

const

{ Event masks }

  PositionalEvents: Word = evMouse;
  FocusedEvents: Word = evKeyboard + evCommand;

{ Minimum window size }

  MinWinSize: TPoint = (X: 16; Y: 6);

{ Shadow definitions }

  ShadowSize: TPoint = (X: 2; Y: 1);
  ShadowAttr: Byte = $08;

{ Markers control }

  ShowMarkers: Boolean = False;

{ MapColor error return value }

  ErrorAttr: Byte = $CF;

{ Stream Registration Records }

  RView: TStreamRec = (
     ObjType: 1;
     VmtLink: Ofs(TypeOf(TView)^);
     Load:    @TView.Load;
     Store:   @TView.Store
  );
  RFrame: TStreamRec = (
     ObjType: 2;
     VmtLink: Ofs(TypeOf(TFrame)^);
     Load:    @TFrame.Load;
     Store:   @TFrame.Store
  );
  RScrollBar: TStreamRec = (
     ObjType: 3;
     VmtLink: Ofs(TypeOf(TScrollBar)^);
     Load:    @TScrollBar.Load;
     Store:   @TScrollBar.Store
  );
  RScroller: TStreamRec = (
     ObjType: 4;
     VmtLink: Ofs(TypeOf(TScroller)^);
     Load:    @TScroller.Load;
     Store:   @TScroller.Store
  );
  RListViewer: TStreamRec = (
     ObjType: 5;
     VmtLink: Ofs(TypeOf(TListViewer)^);
     Load:    @TListViewer.Load;
     Store:   @TLIstViewer.Store
  );
  RGroup: TStreamRec = (
     ObjType: 6;
     VmtLink: Ofs(TypeOf(TGroup)^);
     Load:    @TGroup.Load;
     Store:   @TGroup.Store
  );
  RWindow: TStreamRec = (
     ObjType: 7;
     VmtLink: Ofs(TypeOf(TWindow)^);
     Load:    @TWindow.Load;
     Store:   @TWindow.Store
  );

{ Characters used for drawing selected and default items in  }
{ monochrome color sets                                      }

  SpecialChars: array[0..5] of Char = (#175, #174, #26, #27, ' ', ' ');

{ True if the command set has changed since being set to false }

  CommandSetChanged: Boolean = False;