unit fontsets;

{$MODE OBJFPC}
{$M+}

interface
uses fonts, classes;

// TODO avoid refcounting (just use a TFont directly)?

type
  TFontset = class(TInterfacedObject, IFont, IInterface)
  private
    fFonts : IInterfaceList;
  public
    destructor Destroy(); override;
  published
    constructor Create();
    procedure AppendFont(const aFont : IFont);
    
    function GetGlyph(aCode : Cardinal) : TGlyphP{or nil};
    // GetGlyphOrFallback = GetGlyph or FallbackGlyph
    function GetFallbackGlyph() : TGlyphP; // not nil. // (can't be published in the interface by FPC so exposed as a function, not a property).
  end;

implementation
uses sysutils;

constructor TFontset.Create();
begin
  inherited Create();
  fFonts := TInterfaceList.Create(); // False);
end;

destructor TFontset.Destroy();
begin
  FreeAndNil(fFonts);
  inherited Destroy();
end;

procedure TFontset.AppendFont(const aFont : IFont);
begin
  fFonts.Add(aFont);
end;

function TFontset.GetGlyph(aCode : Cardinal) : TGlyphP{or nil};
var
  i : Integer;
begin
  Result := nil;
  for i := 0 to fFonts.Count - 1 do begin
    Result := IFont(fFonts[i]).GetGlyph(aCode);
    if Assigned(Result) then
      Break;
  end;
end;

function TFontset.GetFallbackGlyph() : TGlyphP; // not nil. // (can't be published in the interface by FPC so exposed as a function, not a property).
var
  i : Integer;
begin
  Result := nil;
  for i := 0 to fFonts.Count - 1 do begin
    Result := IFont(fFonts[i]).GetFallbackGlyph();
    if Assigned(Result) then
      Break;
  end;
end;

end.