+ added unit System.Terminal.View

packages/fcl-fpterm/src/system.terminal.view.pas

@@ -0,0 +1,96 @@
+{ This file is part of fpterm - a terminal emulator, written in Free Pascal
+
+  This unit defines the display of the terminal.
+
+  Copyright (C) 2022, 2024 Nikolay Nikolov <nickysn@users.sourceforge.net>
+
+  This library is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Library General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or (at your
+  option) any later version with the following modification:
+
+  As a special exception, the copyright holders of this library give you
+  permission to link this library with independent modules to produce an
+  executable, regardless of the license terms of these independent modules,and
+  to copy and distribute the resulting executable under terms of your choice,
+  provided that you also meet, for each linked independent module, the terms
+  and conditions of the license of that module. An independent module is a
+  module which is not derived from or based on this library. If you modify
+  this library, you may extend this exception to your version of the library,
+  but you are not obligated to do so. If you do not wish to do so, delete this
+  exception statement from your version.
+
+  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. See the GNU Library General Public License
+  for more details.
+
+  You should have received a copy of the GNU Library General Public License
+  along with this library; if not, write to the Free Software Foundation,
+  Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1335, USA.
+}
+
+unit System.Terminal.View;
+
+{$mode objfpc}{$H+}
+
+interface
+
+uses
+  System.Terminal.Base;
+
+type
+
+  { TTerminalView }
+
+  TTerminalView = class
+  protected
+    FReverseVideo: Boolean;
+
+    function GetCursorX: Integer; virtual; abstract;
+    function GetCursorY: Integer; virtual; abstract;
+    function GetHeight: Integer; virtual; abstract;
+    function GetWidth: Integer; virtual; abstract;
+    procedure SetCell(Y, X: Integer; AValue: TCell); virtual; abstract;
+  public
+    constructor Create; virtual;
+
+    procedure UpdateScreen; virtual; abstract;
+    procedure IdleLoop; virtual; abstract;
+    procedure HideCursor; virtual; abstract;
+    procedure ShowCursor; virtual; abstract;
+    procedure StartBlinkingCursor; virtual; abstract;
+    procedure StopBlinkingCursor; virtual; abstract;
+    procedure SetCursorPos(NewCursorX, NewCursorY: Integer); virtual; abstract;
+
+    { Requests the view to resize itself. Can be triggered in response to a
+      CheckPendingResize call returning true, but also by other events, such as
+      by certain ESC sequences (i.e. resize requested by the app). }
+    function Resize(NewWidth, NewHeight: Integer): Boolean; virtual; abstract;
+
+    { Checks for a resize event, initiated by the view (for example, a window
+      resize, initiated by the user, by resizing the console window with the
+      mouse). }
+    function CheckPendingResize(out NewWidth, NewHeight: Integer): Boolean; virtual; abstract;
+
+    { Returns the number of character cells needed for the display of the given string }
+    function StringDisplayWidth(const S: UnicodeString): Integer; virtual; abstract;
+
+    property CursorX: Integer read GetCursorX;
+    property CursorY: Integer read GetCursorY;
+    property Width: Integer read GetWidth;
+    property Height: Integer read GetHeight;
+    property Cell [Y, X: Integer]: TCell {read GetCell} write SetCell;
+    property ReverseVideo: Boolean read FReverseVideo write FReverseVideo;
+  end;
+
+implementation
+
+{ TTerminalView }
+
+constructor TTerminalView.Create;
+begin
+end;
+
+end.
+