-- Created on: 2008-01-20
-- Created by: Alexander A. BORODIN
-- Copyright (c) 2008-2012 OPEN CASCADE SAS
--
-- The content of this file is subject to the Open CASCADE Technology Public
-- License Version 6.5 (the "License"). You may not use the content of this file
-- except in compliance with the License. Please obtain a copy of the License
-- at http://www.opencascade.org and read it completely before using this file.
--
-- The Initial Developer of the Original Code is Open CASCADE S.A.S., having its
-- main offices at: 1, place des Freres Montgolfier, 78280 Guyancourt, France.
--
-- The Original Code and all software distributed under the License is
-- distributed on an "AS IS" basis, without warranty of any kind, and the
-- Initial Developer hereby disclaims all such warranties, including without
-- limitation, any warranties of merchantability, fitness for a particular
-- purpose or non-infringement. Please see the License for the specific terms
-- and conditions governing the rights and limitations under the License.

class FontMgr from Font inherits TShared from MMgt
---Purpose: Collects and provides information about available fonts in system.
---On Windows it gets information about available fonts from registry value
---"HKLM\\SOFTWARE\\Microsoft\\Windows NT\\CurrentVersion\\Fonts". If the description
---of the font does not contain the full path to it, FontMgr looks for it in the
---default fonts directory. (WinAPI function GetSystemWindowsDirectory is used
---to get the path of the shared Windows directory on a multi-user system.)
---On Linux and Mac OS X platforms for getting the directories with fonts, at first
---it checks X11 configuration files, which can be located at "/etc/X11/fs/config",
---"/usr/X11R6/lib/X11/fs/config" or "/usr/X11/lib/X11/fs/config". Then it adds
---default directories(for Linux: "/usr/share/fonts" and "/usr/local/share/fonts",
---for Mac OS X: "/System/Library/Fonts" and "/Library/Fonts"). After that FontMgr
---looks for the "fonts.dir" file in each stored directory. This file contain 
---fonts description in XLFD (X Logical Font Description) format. 
---On all platforms (Windows, Linux, Mac OS X) we use FreeType library for getting
---font name and aspect.
---On Linux and Mac OS X in cases when the font description obtained from FreeType
---does not match the description in XLFD, FontMgr stores such fonts as two different
---fonts (font management feature on Unix systems).

uses FontAspect,
     SystemFont,
     NListOfSystemFont,
     Path from OSD,
     AsciiString from TCollection,
     HAsciiString from TCollection,
     SequenceOfHAsciiString from TColStd
is
  GetInstance(myclass) returns FontMgr;
  ---Level: Public

  GetAvailableFonts(me) returns NListOfSystemFont;
  ---C++: return const &
  
  GetAvailableFontsNames(me;
                         theFontsNames: out SequenceOfHAsciiString);
  ---Purpose: Returns sequence of available fonts names
  ---Level: Public
    
  GetFont (me;
           theFontName   : HAsciiString;
           theFontAspect : FontAspect;
           theFontSize   : Integer) returns SystemFont;
  ---Purpose: Returns font that match given parameters.
  ---         If theFontName is empty string returned font can have any FontName.
  ---         If theFontAspect is Font_FA_Undefined returned font can have any FontAspect.
  ---         If theFontSize is "-1" returned font can have any FontSize.
  ---Level: Public

  FindFont (me;
            theFontName   : HAsciiString;
            theFontAspect : FontAspect;
            theFontSize   : Integer) returns SystemFont;
  ---Purpose: Tries to find font by given parameters.
  ---         If the specified font is not found tries to use font names mapping.
  ---         If the requested family name not found -> search for any font family
  ---         with given aspect and height. If the font is still not found, returns
  ---         any font available in the system. Returns NULL in case when the fonts
  ---         are not found in the system.
  ---Level: Public

  CheckFont (me; theFontPath : CString from Standard) returns SystemFont;
  ---Purpose: Read font file and retrieve information from it.
  ---Level: Public

  RegisterFont (me            : mutable;
                theFont       : SystemFont;
                theToOverride : Boolean from Standard) returns Boolean from Standard;
  ---Purpose: Register new font.
  ---         If there is existing entity with the same name and properties but different path
  ---         then font will will be overridden or ignored depending on theToOverride flag.
  ---Level: Public

  --- Private methods

  Create returns FontMgr is private;
  ---Purpose: Creates empty font object
  ---Level: Private

  InitFontDataBase(me:mutable) is private;
  ---Purpose: Collects available fonts paths.
  ---Level: Private

fields

  myListOfFonts : NListOfSystemFont;

end FontMgr;