program LicenseHeaderFix;

{$APPTYPE CONSOLE}

uses
  System.Types,
  System.IOUtils,
  System.Classes,
  System.SysUtils,
  System.RegularExpressions;

procedure ApplyFix(
  const ASearchPath: string;
  const AHeaderFileName: string
);
var
  I: Integer;
  VCount: Integer;
  VList: TStringDynArray;
  VText: string;
  VBytes: TBytes;
  VHeader: string;
  VRegEx: TRegEx;
  VMatch: TMatch;
begin
  VHeader := TFile.ReadAllText(AHeaderFileName) + #13#10;

  VRegEx := TRegEx.Create(
    '^unit (.*?);',
    [roIgnoreCase, roMultiLine, roCompiled, roNotEmpty]
  );

  VList := TDirectory.GetFiles(
    ASearchPath,
    '*.pas',
    TSearchOption.soAllDirectories
  );

  VCount := 0;
  for I := 0 to Length(VList) - 1 do begin
    VText := TFile.ReadAllText(VList[I]);
    VMatch := VRegEx.Match(VText);
    if VMatch.Success then begin
      VText := VHeader + Copy(VText, Pos(VMatch.Value, VText));

      VBytes := TEncoding.ANSI.GetBytes(AnsiString(VText)); // !

      TFile.WriteAllBytes(VList[I], VBytes);
      Inc(VCount);
    end else begin
      WriteLn('Match failed: ', VList[I]);
    end;
  end;

  Writeln('Processed: ', VCount, '/', Length(VList));
end;

begin
  try
    ApplyFix(
      'c:\tmp\sas.planet.src\Src\',
      'c:\tmp\NewHeader.txt'
    );
  except
    on E: Exception do
      Writeln(E.ClassName, ': ', E.Message);
  end;

  Writeln('Press Enter to exit...');
  ReadLn;
end.