{* UltraStar Deluxe - Karaoke Game
 *
 * UltraStar Deluxe is the legal property of its developers, whose names
 * are too numerous to list here. Please refer to the COPYRIGHT
 * file distributed with this source distribution.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; see the file COPYING. If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 *
 * $URL$
 * $Id$
 *}

unit USong;

interface

{$IFDEF FPC}
  {$MODE Delphi}
{$ENDIF}

{$I switches.inc}

uses
  {$IFDEF MSWINDOWS}
    Windows,
  {$ELSE}
    {$IFNDEF DARWIN}
      syscall,
    {$ENDIF}
    baseunix,
    UnixType,
  {$ENDIF}
  SysUtils,
  Classes,
  UPlatform,
  ULog,
  UTexture,
  UCommon,
  {$IFDEF DARWIN}
    cthreads,
  {$ENDIF}
  {$IFDEF USE_PSEUDO_THREAD}
    PseudoThread,
  {$ENDIF}
  UCatCovers,
  UXMLSong,
  UUnicodeUtils,
  UTextEncoding,
  UFilesystem,
  UPath;

type

  TSingMode = ( smNormal, smPartyMode, smPlaylistRandom );

  TBPM = record
    BPM:        real;
    StartBeat:  real;
  end;

  TScore = record
    Name:       UTF8String;
    Score:      integer;
  end;

  TSong = class
  private
    FileLineNo  : integer;  // line, which is read last, for error reporting

    function DecodeFilename(Filename: RawByteString): IPath;
    function Solmizate(Note: integer; Type_: integer): string;
    procedure ParseNote(LineNumber: integer; TypeP: char; StartP, DurationP, NoteP: integer; LyricS: UTF8String);
    procedure NewSentence(LineNumberP: integer; Param1, Param2: integer);

    function ParseLyricStringParam(const Line: RawByteString; var LinePos: integer): RawByteString;
    function ParseLyricIntParam(const Line: RawByteString; var LinePos: integer): integer;
    function ParseLyricFloatParam(const Line: RawByteString; var LinePos: integer): real;
    function ParseLyricCharParam(const Line: RawByteString; var LinePos: integer): AnsiChar;
    function ParseLyricText(const Line: RawByteString; var LinePos: integer): RawByteString;

    function ReadTXTHeader(SongFile: TTextFileStream): boolean;
    function ReadXMLHeader(const aFileName: IPath): boolean;

    function GetFolderCategory(const aFileName: IPath): UTF8String;
    function FindSongFile(Dir: IPath; Mask: UTF8String): IPath;

  public
    Path:         IPath; // kust path component of file (only set if file was found)
    Folder:       UTF8String; // for sorting by folder (only set if file was found)
    FileName:     IPath; // just name component of file (only set if file was found)

    // filenames
    Cover:      IPath;
    Mp3:        IPath;
    Background: IPath;
    Video:      IPath;
    
    // sorting methods
    Genre:      UTF8String;
    Edition:    UTF8String;
    Language:   UTF8String;

    Title:      UTF8String;
    Artist:     UTF8String;

    Creator:    UTF8String;

    CoverTex:   TTexture;
    
    VideoGAP:   real;
    NotesGAP:   integer;
    Start:      real; // in seconds
    Finish:     integer; // in miliseconds
    Relative:   boolean;
    Resolution: integer;
    BPM:        array of TBPM;
    GAP:        real; // in miliseconds

    Encoding:   TEncoding;

    Score:      array[0..2] of array of TScore;

    // these are used when sorting is enabled
    Visible:    boolean; // false if hidden, true if visible
    Main:       boolean; // false for songs, true for category buttons
    OrderNum:   integer; // has a number of category for category buttons and songs
    OrderTyp:   integer; // type of sorting for this button (0=name)
    CatNumber:  integer; // Count of Songs in Category for Cats and Number of Song in Category for Songs

    Base    : array[0..1] of integer;
    Rel     : array[0..1] of integer;
    Mult    : integer;
    MultBPM : integer;

    LastError: AnsiString;
    function  GetErrorLineNo: integer;
    property  ErrorLineNo: integer read GetErrorLineNo;


    constructor Create(); overload;
    constructor Create(const aFileName : IPath); overload;
    function    LoadSong: boolean;
    function    LoadXMLSong: boolean;
    function    Analyse(): boolean;
    function    AnalyseXML(): boolean;
    procedure   Clear();
  end;

implementation

uses
  StrUtils,
  TextGL,
  UIni,
  UPathUtils,
  UMusic,  //needed for Lines
  UNote;   //needed for Player

const
  // use USDX < 1.1 encoding for backward compatibility
  DEFAULT_ENCODING = encCP1252;

constructor TSong.Create();
begin
  inherited;
end;

// This may be changed, when we rewrite song select code.
// it is some kind of dirty, but imho the best possible
// solution as we do atm not support nested categorys.
// it works like the folder sorting in 1.0.1a
// folder is set to the first folder under the songdir
// so songs ~/.ultrastardx/songs/punk is in the same
// category as songs in shared/ultrastardx/songs are.
// note: folder is just the name of a category it has
//       nothing to do with the path used for file loading
function TSong.GetFolderCategory(const aFileName: IPath): UTF8String;
var
  I: Integer;
  CurSongPath: IPath;
  CurSongPathRel: IPath;
begin
  Result := 'Unknown'; //default folder category, if we can't locate the song dir

  for I := 0 to SongPaths.Count-1 do
  begin
    CurSongPath := SongPaths[I] as IPath;
    if (aFileName.IsChildOf(CurSongPath, false)) then
    begin
      if (aFileName.IsChildOf(CurSongPath, true)) then
      begin
        // songs are in the "root" of the songdir => use songdir for the categorys name
        Result := CurSongPath.ToUTF8; // TODO: remove trailing path-delim?
      end
      else
      begin
        // use the first subdirectory below CurSongPath as the category name
        CurSongPathRel := aFileName.GetRelativePath(CurSongPath.AppendPathDelim);
        Result := CurSongPathRel.SplitDirs[0].RemovePathDelim.ToUTF8;
      end;
      Exit;
    end;
  end;
end;

constructor TSong.Create(const aFileName: IPath);
begin
  inherited Create();

  Mult    := 1;
  MultBPM := 4;

  LastError := '';

  Self.Path     := aFileName.GetPath;
  Self.FileName := aFileName.GetName;
  Self.Folder   := GetFolderCategory(aFileName);

  (*
  if (aFileName.IsFile) then
  begin
    if ReadTXTHeader(aFileName) then
    begin
      LoadSong();
    end
    else
    begin
      Log.LogError('Error Loading SongHeader, abort Song Loading');
      Exit;
    end;
  end;
  *)
end;

function TSong.FindSongFile(Dir: IPath; Mask: UTF8String): IPath;
var
  Iter: IFileIterator;
  FileInfo: TFileInfo;
  FileName: IPath;
begin
  Iter := FileSystem.FileFind(Dir.Append(Mask), faDirectory);
  if (Iter.HasNext) then
    Result := Iter.Next.Name
  else
    Result := PATH_NONE;
end;

function TSong.DecodeFilename(Filename: RawByteString): IPath;
begin
  Result := UPath.Path(DecodeStringUTF8(Filename, Encoding));
end;

type
  EUSDXParseException = class(Exception);

{**
 * Parses the Line string starting from LinePos for a parameter.
 * Leading whitespace is trimmed, same applies to the first trailing whitespace.
 * After the call LinePos will point to the position after the first trailing
 * whitespace.
 *
 * Raises an EUSDXParseException if no string was found.
 *
 * Example:
 *   ParseLyricParam(Line:'Param0  Param1 Param2', LinePos:8, ...)
 *   -> Param:'Param1', LinePos:16 (= start of 'Param2')
 *}
function TSong.ParseLyricStringParam(const Line: RawByteString; var LinePos: integer): RawByteString;
var
  Start: integer;
  OldLinePos: integer;
const
  Whitespace = [#9, ' '];
begin
  OldLinePos := LinePos;

  Start := 0;
  while (LinePos <= Length(Line)) do
  begin
    if (Line[LinePos] in Whitespace) then
    begin
      // check for end of param
      if (Start > 0) then
        Break;
    end
    // check for beginning of param
    else if (Start = 0) then
    begin
      Start := LinePos;
    end;
    Inc(LinePos);
  end;

  // check if param was found
  if (Start = 0) then
  begin
    LinePos := OldLinePos;
    raise EUSDXParseException.Create('String expected');
  end
  else
  begin
    // copy param without trailing whitespace
    Result := Copy(Line, Start, LinePos-Start);
    // skip first trailing whitespace (if not at EOL)
    if (LinePos <= Length(Line)) then
      Inc(LinePos);
  end;
end;

function TSong.ParseLyricIntParam(const Line: RawByteString; var LinePos: integer): integer;
var
  Str: RawByteString;
  OldLinePos: integer;
begin
  OldLinePos := LinePos;
  Str := ParseLyricStringParam(Line, LinePos);
  try
    Result := StrToInt(Str);
  except // on EConvertError
    LinePos := OldLinePos;
    raise EUSDXParseException.Create('Integer expected');
  end;
end;

function TSong.ParseLyricFloatParam(const Line: RawByteString; var LinePos: integer): real;
var
  Str: RawByteString;
  OldLinePos: integer;
begin
  OldLinePos := LinePos;
  Str := ParseLyricStringParam(Line, LinePos);
  try
    Result := StrToFloat(Str);
  except // on EConvertError
    LinePos := OldLinePos;
    raise EUSDXParseException.Create('Float expected');
  end;
end;

function TSong.ParseLyricCharParam(const Line: RawByteString; var LinePos: integer): AnsiChar;
var
  Str: RawByteString;
  OldLinePos: integer;
begin
  OldLinePos := LinePos;
  Str := ParseLyricStringParam(Line, LinePos);
  if (Length(Str) <> 1) then
  begin
    LinePos := OldLinePos;
    raise EUSDXParseException.Create('Character expected');
  end;
  Result := Str[1];  
end;

{**
 * Returns the rest of the line from LinePos as lyric text.
 * Leading and trailing whitespace is not trimmed.
 *}
function TSong.ParseLyricText(const Line: RawByteString; var LinePos: integer): RawByteString;
begin
  if (LinePos > Length(Line)) then
    Result := ''
  else
  begin
    Result := Copy(Line, LinePos, Length(Line)-LinePos+1);
    LinePos := Length(Line)+1;
  end;
end;

//Load TXT Song
function TSong.LoadSong(): boolean;
var
  CurLine: RawByteString;
  LinePos:  integer;
  Count:    integer;
  Both:     boolean;

  Param0:    AnsiChar;
  Param1:    integer;
  Param2:    integer;
  Param3:    integer;
  ParamLyric: UTF8String;

  I:        integer;
  NotesFound: boolean;
  SongFile: TTextFileStream;
  FileNamePath: IPath;
begin
  Result := false;
  LastError := '';

  FileNamePath := Path.Append(FileName);
  if not FileNamePath.IsFile() then
  begin
    LastError := 'ERROR_CORRUPT_SONG_FILE_NOT_FOUND';
    Log.LogError('File not found: "' + FileNamePath.ToNative + '"', 'TSong.LoadSong()');
    Exit;
  end;

  MultBPM           := 4; // multiply beat-count of note by 4
  Mult              := 1; // accuracy of measurement of note
  Rel[0]            := 0;
  Both              := false;

  if Length(Player) = 2 then
    Both := true;

  try
    // Open song file for reading.....
    SongFile := TMemTextFileStream.Create(FileNamePath, fmOpenRead);
    try
      //Search for Note Beginning
      FileLineNo := 0;
      NotesFound := false;
      while (SongFile.ReadLine(CurLine)) do
      begin
        Inc(FileLineNo);
        if (Length(CurLine) > 0) and (CurLine[1] in [':', 'F', '*']) then
        begin
          NotesFound := true;
          Break;
        end;
      end;

      if (not NotesFound) then
      begin //Song File Corrupted - No Notes
        Log.LogError('Could not load txt File, no notes found: ' + FileNamePath.ToNative);
        LastError := 'ERROR_CORRUPT_SONG_NO_NOTES';
        Exit;
      end;

      SetLength(Lines, 2);
      for Count := 0 to High(Lines) do
      begin
        Lines[Count].High := 0;
        Lines[Count].Number := 1;
        Lines[Count].Current := 0;
        Lines[Count].Resolution := self.Resolution;
        Lines[Count].NotesGAP   := self.NotesGAP;
        Lines[Count].ScoreValue := 0;

        //Add first line and set some standard values to fields
        //see procedure NewSentence for further explantation
        //concerning most of these values
        SetLength(Lines[Count].Line, 1);
        Lines[Count].Line[0].HighNote := -1;
        Lines[Count].Line[0].LastLine := false;
        Lines[Count].Line[0].BaseNote := High(Integer);
        Lines[Count].Line[0].TotalNotes := 0;
      end;

      while true do
      begin
        LinePos := 0;

        Param0 := ParseLyricCharParam(CurLine, LinePos);
        if (Param0 = 'E') then
        begin
          Break
        end
        else if (Param0 in [':', '*', 'F']) then
        begin
          // read notes
          Param1 := ParseLyricIntParam(CurLine, LinePos);
          Param2 := ParseLyricIntParam(CurLine, LinePos);
          Param3 := ParseLyricIntParam(CurLine, LinePos);
          ParamLyric := ParseLyricText(CurLine, LinePos);

          //Check for ZeroNote
          if Param2 = 0 then
            Log.LogError('Found zero-length note at "'+Param0+' '+IntToStr(Param1)+' '+IntToStr(Param2)+' '+IntToStr(Param3)+ParamLyric+'" -> Note ignored!')
          else
          begin
           // add notes
           if not Both then
             // P1
             ParseNote(0, Param0, (Param1+Rel[0]) * Mult, Param2 * Mult, Param3, ParamLyric)
           else
           begin
             // P1 + P2
             ParseNote(0, Param0, (Param1+Rel[0]) * Mult, Param2 * Mult, Param3, ParamLyric);
             ParseNote(1, Param0, (Param1+Rel[1]) * Mult, Param2 * Mult, Param3, ParamLyric);
           end;
          end; //Zeronote check
        end // if

        else if Param0 = '-' then
        begin
          // reads sentence
          Param1 := ParseLyricIntParam(CurLine, LinePos);
          if self.Relative then
            Param2 := ParseLyricIntParam(CurLine, LinePos); // read one more data for relative system

          // new sentence
          if not Both then
            // P1
            NewSentence(0, (Param1 + Rel[0]) * Mult, Param2)
          else
          begin
            // P1 + P2
            NewSentence(0, (Param1 + Rel[0]) * Mult, Param2);
            NewSentence(1, (Param1 + Rel[1]) * Mult, Param2);
          end;
        end // if

        else if Param0 = 'B' then
        begin
          SetLength(self.BPM, Length(self.BPM) + 1);
          self.BPM[High(self.BPM)].StartBeat := ParseLyricFloatParam(CurLine, LinePos);
          self.BPM[High(self.BPM)].StartBeat := self.BPM[High(self.BPM)].StartBeat + Rel[0];

          self.BPM[High(self.BPM)].BPM := ParseLyricFloatParam(CurLine, LinePos);
          self.BPM[High(self.BPM)].BPM := self.BPM[High(self.BPM)].BPM * Mult * MultBPM;
        end;

        // Read next line in File
        if (not SongFile.ReadLine(CurLine)) then
          Break;

        Inc(FileLineNo);
      end; // while
    finally
      SongFile.Free;
    end;
  except
    on E: Exception do
    begin
      Log.LogError(Format('Error loading file: "%s" in line %d,%d: %s',
                  [FileNamePath.ToNative, FileLineNo, LinePos, E.Message]));
      Exit;
    end;
  end;

  for I := 0 to High(Lines) do
  begin
    if ((Both) or (I = 0)) then
    begin
      if (Length(Lines[I].Line) < 2) then
      begin
        LastError := 'ERROR_CORRUPT_SONG_NO_BREAKS';
        Log.LogError('Error loading file: Can''t find any linebreaks in "' + FileNamePath.ToNative + '"');
        exit;
      end;

      if (Lines[I].Line[Lines[I].High].HighNote < 0) then
      begin
        SetLength(Lines[I].Line, Lines[I].Number - 1);
        Lines[I].High := Lines[I].High - 1;
        Lines[I].Number := Lines[I].Number - 1;
        Log.LogError('Error loading Song, sentence w/o note found in last line before E: ' + FileNamePath.ToNative);
      end;
    end;
  end;

  for Count := 0 to High(Lines) do
  begin
    if (High(Lines[Count].Line) >= 0) then
      Lines[Count].Line[High(Lines[Count].Line)].LastLine := true;
  end;

  Result := true;
end;

//Load XML Song
function TSong.LoadXMLSong(): boolean;
var
  Count:     integer;
  Both:      boolean;
  Param1:    integer;
  Param2:    integer;
  Param3:    integer;
  ParamS:    string;
  I, J:      integer;
  NoteIndex: integer;

  NoteType:  char;
  SentenceEnd, Rest, Time: integer;
  Parser: TParser;
  FileNamePath: IPath;
begin
  Result := false;
  LastError := '';

  FileNamePath := Path.Append(FileName);
  if not FileNamePath.IsFile() then
  begin
    Log.LogError('File not found: "' + FileNamePath.ToNative + '"', 'TSong.LoadSong()');
    exit;
  end;

  MultBPM           := 4; // multiply beat-count of note by 4
  Mult              := 1; // accuracy of measurement of note
  Lines[0].ScoreValue := 0;
  self.Relative     := false;
  Rel[0]            := 0;
  Both              := false;

  if Length(Player) = 2 then
    Both := true;

  Parser := TParser.Create;
  Parser.Settings.DashReplacement := '~';

  for Count := 0 to High(Lines) do
  begin
    Lines[Count].High := 0;
      Lines[Count].Number := 1;
      Lines[Count].Current := 0;
      Lines[Count].Resolution := self.Resolution;
      Lines[Count].NotesGAP   := self.NotesGAP;
      Lines[Count].ScoreValue := 0;

      //Add first line and set some standard values to fields
      //see procedure NewSentence for further explantation
      //concerning most of these values
      SetLength(Lines[Count].Line, 1);
      Lines[Count].Line[0].HighNote := -1;
      Lines[Count].Line[0].LastLine := false;
      Lines[Count].Line[0].BaseNote := High(Integer);
      Lines[Count].Line[0].TotalNotes := 0;
  end;

  //Try to Parse the Song

  if Parser.ParseSong(FileNamePath) then
  begin
    //Writeln('XML Inputfile Parsed succesful');

    //Start write parsed information to Song
    //Notes Part
    for I := 0 to High(Parser.SongInfo.Sentences) do
    begin
      //Add Notes
      for J := 0 to High(Parser.SongInfo.Sentences[I].Notes) do
      begin
        case Parser.SongInfo.Sentences[I].Notes[J].NoteTyp of
          NT_Normal:    NoteType := ':';
          NT_Golden:    NoteType := '*';
          NT_Freestyle: NoteType := 'F';
        end;

        Param1:=Parser.SongInfo.Sentences[I].Notes[J].Start;       //Note Start
        Param2:=Parser.SongInfo.Sentences[I].Notes[J].Duration;    //Note Duration
        Param3:=Parser.SongInfo.Sentences[I].Notes[J].Tone;        //Note Tone
        ParamS:=' ' + Parser.SongInfo.Sentences[I].Notes[J].Lyric; //Note Lyric

        if not Both then
          // P1
          ParseNote(0, NoteType, (Param1+Rel[0]) * Mult, Param2 * Mult, Param3, ParamS)
        else
        begin
          // P1 + P2
          ParseNote(0, NoteType, (Param1+Rel[0]) * Mult, Param2 * Mult, Param3, ParamS);
          ParseNote(1, NoteType, (Param1+Rel[1]) * Mult, Param2 * Mult, Param3, ParamS);
        end;

      end; //J Forloop

      //Add Sentence break
      if (I < High(Parser.SongInfo.Sentences)) then
      begin
        SentenceEnd := Parser.SongInfo.Sentences[I].Notes[High(Parser.SongInfo.Sentences[I].Notes)].Start + Parser.SongInfo.Sentences[I].Notes[High(Parser.SongInfo.Sentences[I].Notes)].Duration;
        Rest := Parser.SongInfo.Sentences[I+1].Notes[0].Start - SentenceEnd;

        //Calculate Time
        case Rest of
          0, 1: Time := Parser.SongInfo.Sentences[I+1].Notes[0].Start;
          2:    Time := Parser.SongInfo.Sentences[I+1].Notes[0].Start - 1;
          3:    Time := Parser.SongInfo.Sentences[I+1].Notes[0].Start - 2;
          else
            if (Rest >= 4) then
              Time := SentenceEnd + 2
            else //Sentence overlapping :/
              Time := Parser.SongInfo.Sentences[I+1].Notes[0].Start;
        end;
        // new sentence
        if not Both then // P1
          NewSentence(0, (Time + Rel[0]) * Mult, Param2)
        else
        begin // P1 + P2
          NewSentence(0, (Time + Rel[0]) * Mult, Param2);
          NewSentence(1, (Time + Rel[1]) * Mult, Param2);
        end;

      end;
    end;
    //End write parsed information to Song
    Parser.Free;
  end
  else
  begin
    Log.LogError('Could not parse inputfile: ' + FileNamePath.ToNative);
    exit;
  end;

  for Count := 0 to High(Lines) do
  begin
    Lines[Count].Line[High(Lines[Count].Line)].LastLine := true;
  end;

  Result := true;
end;

function TSong.ReadXMLHeader(const aFileName : IPath): boolean;
var
  Done        : byte;
  Parser      : TParser;
  FileNamePath: IPath;
begin
  Result := true;
  Done   := 0;

  //Parse XML
  Parser := TParser.Create;
  Parser.Settings.DashReplacement := '~';

  FileNamePath := Self.Path.Append(Self.FileName);
  if Parser.ParseSong(FileNamePath) then
  begin
    //-----------
    //Required Attributes
    //-----------

    //Title
    self.Title := Parser.SongInfo.Header.Title;

    //Add Title Flag to Done
    Done := Done or 1;

    //Artist
    self.Artist := Parser.SongInfo.Header.Artist;

    //Add Artist Flag to Done
    Done := Done or 2;

    //MP3 File //Test if Exists
    Self.Mp3 := FindSongFile(Self.Path, '*.mp3');
    //Add Mp3 Flag to Done
    if (Self.Path.Append(Self.Mp3).IsFile()) then
      Done := Done or 4;

    //Beats per Minute
    SetLength(self.BPM, 1);
    self.BPM[0].StartBeat := 0;

    self.BPM[0].BPM := (Parser.SongInfo.Header.BPM * Parser.SongInfo.Header.Resolution/4  ) * Mult * MultBPM;

    //Add BPM Flag to Done
    if self.BPM[0].BPM <> 0 then
      Done := Done or 8;

    //---------
    //Additional Header Information
    //---------

    // Gap
    self.GAP := Parser.SongInfo.Header.Gap;

    //Cover Picture
    self.Cover := FindSongFile(Path, '*[CO].jpg');

    //Background Picture
    self.Background := FindSongFile(Path, '*[BG].jpg');

    // Video File
    //    self.Video := Value

    // Video Gap
    //  self.VideoGAP := StrtoFloatI18n( Value )

    //Genre Sorting
    self.Genre := Parser.SongInfo.Header.Genre;

    //Edition Sorting
    self.Edition := Parser.SongInfo.Header.Edition;

    //Year Sorting
    //Parser.SongInfo.Header.Year

    //Language Sorting
    self.Language := Parser.SongInfo.Header.Language;
  end
  else
    Log.LogError('File incomplete or not SingStar XML (A): ' + aFileName.ToNative);

  Parser.Free;

  //Check if all Required Values are given
  if (Done <> 15) then
  begin
    Result := false;
    if (Done and 8) = 0 then      //No BPM Flag
      Log.LogError('BPM tag missing: ' + self.FileName.ToNative)
    else if (Done and 4) = 0 then //No MP3 Flag
      Log.LogError('MP3 tag/file missing: ' + self.FileName.ToNative)
    else if (Done and 2) = 0 then //No Artist Flag
      Log.LogError('Artist tag missing: ' + self.FileName.ToNative)
    else if (Done and 1) = 0 then //No Title Flag
      Log.LogError('Title tag missing: ' + self.FileName.ToNative)
    else //unknown Error
      Log.LogError('File incomplete or not SingStar XML (B - '+ inttostr(Done) +'): ' + aFileName.ToNative);
  end;

end;


{**
 * "International" StrToFloat variant. Uses either ',' or '.' as decimal
 * separator.
 *}
function StrToFloatI18n(const Value: string): extended;
var
  TempValue : string;
begin
  TempValue := Value;
  if (Pos(',', TempValue) <> 0) then
    TempValue[Pos(',', TempValue)] := '.';
  Result := StrToFloatDef(TempValue, 0);
end;

function TSong.ReadTXTHeader(SongFile: TTextFileStream): boolean;
var
  Line, Identifier: string;
  Value: string;
  SepPos: integer; // separator position
  Done: byte;      // bit-vector of mandatory fields
  EncFile: IPath; // encoded filename
  FullFileName: string;
begin
  Result := true;
  Done   := 0;

  FullFileName := Path.Append(Filename).ToNative;

  //Read first Line
  SongFile.ReadLine(Line);
  if (Length(Line) <= 0) then
  begin
    Log.LogError('File starts with empty line: ' + FullFileName,
                 'TSong.ReadTXTHeader');
    Result := false;
    Exit;
  end;

  // check if file begins with a UTF-8 BOM, if so set encoding to UTF-8
  if (CheckReplaceUTF8BOM(Line)) then
    Encoding := encUTF8;

  //Read Lines while Line starts with # or its empty
  while (Length(Line) = 0) or (Line[1] = '#') do
  begin
    //Increase Line Number
    Inc (FileLineNo);
    SepPos := Pos(':', Line);

    //Line has no Seperator, ignore non header field
    if (SepPos = 0) then
      Continue;

    //Read Identifier and Value
    Identifier  := UpperCase(Trim(Copy(Line, 2, SepPos - 2))); //Uppercase is for Case Insensitive Checks
    Value       := Trim(Copy(Line, SepPos + 1, Length(Line) - SepPos));

    //Check the Identifier (If Value is given)
    if (Length(Value) = 0) then
    begin
      Log.LogWarn('Empty field "'+Identifier+'" in file ' + FullFileName,
                   'TSong.ReadTXTHeader');
    end
    else
    begin
    
      //-----------
      //Required Attributes
      //-----------

      if (Identifier = 'TITLE') then
      begin
        DecodeStringUTF8(Value, Title, Encoding);
        //Add Title Flag to Done
        Done := Done or 1;
      end

      else if (Identifier = 'ARTIST') then
      begin
        DecodeStringUTF8(Value, Artist, Encoding);
        //Add Artist Flag to Done
        Done := Done or 2;
      end

      //MP3 File
      else if (Identifier = 'MP3') then
      begin
        EncFile := DecodeFilename(Value);
        if (Self.Path.Append(EncFile).IsFile) then
        begin
          self.Mp3 := EncFile;

          //Add Mp3 Flag to Done
          Done := Done or 4;
        end;
      end

      //Beats per Minute
      else if (Identifier = 'BPM') then
      begin
        SetLength(self.BPM, 1);
        self.BPM[0].StartBeat := 0;

        self.BPM[0].BPM := StrToFloatI18n( Value ) * Mult * MultBPM;

        if self.BPM[0].BPM <> 0 then
        begin
          //Add BPM Flag to Done
          Done := Done or 8;
        end;
      end

      //---------
      //Additional Header Information
      //---------

      // Gap
      else if (Identifier = 'GAP') then
      begin
        self.GAP := StrToFloatI18n(Value);
      end

      //Cover Picture
      else if (Identifier = 'COVER') then
      begin
        self.Cover := DecodeFilename(Value);
      end

      //Background Picture
      else if (Identifier = 'BACKGROUND') then
      begin
        self.Background := DecodeFilename(Value);
      end

      // Video File
      else if (Identifier = 'VIDEO') then
      begin
        EncFile := DecodeFilename(Value);
        if (self.Path.Append(EncFile).IsFile) then
          self.Video := EncFile
        else
          Log.LogError('Can''t find video file in song: ' + FullFileName);
      end

      // Video Gap
      else if (Identifier = 'VIDEOGAP') then
      begin
        self.VideoGAP := StrToFloatI18n( Value )
      end

      //Genre Sorting
      else if (Identifier = 'GENRE') then
      begin
        DecodeStringUTF8(Value, Genre, Encoding)
      end

      //Edition Sorting
      else if (Identifier = 'EDITION') then
      begin
        DecodeStringUTF8(Value, Edition, Encoding)
      end

      //Creator Tag
      else if (Identifier = 'CREATOR') then
      begin
        DecodeStringUTF8(Value, Creator, Encoding)
      end

      //Language Sorting
      else if (Identifier = 'LANGUAGE') then
      begin
        DecodeStringUTF8(Value, Language, Encoding)
      end

      // Song Start
      else if (Identifier = 'START') then
      begin
        self.Start := StrToFloatI18n( Value )
      end

      // Song Ending
      else if (Identifier = 'END') then
      begin
        TryStrtoInt(Value, self.Finish)
      end

      // Resolution
      else if (Identifier = 'RESOLUTION') then
      begin
        TryStrtoInt(Value, self.Resolution)
      end

      // Notes Gap
      else if (Identifier = 'NOTESGAP') then
      begin
        TryStrtoInt(Value, self.NotesGAP)
      end

      // Relative Notes
      else if (Identifier = 'RELATIVE') then
      begin
        if (UpperCase(Value) = 'YES') then
          self.Relative := true;
      end

      // File encoding
      else if (Identifier = 'ENCODING') then
      begin
        self.Encoding := ParseEncoding(Value, DEFAULT_ENCODING);
      end;
      
    end; // End check for non-empty Value

    // read next line
    if (not SongFile.ReadLine(Line)) then
    begin
      Result := false;
      Log.LogError('File incomplete or not Ultrastar txt (A): ' + FullFileName);
      Break;
    end;
  end; // while

  if self.Cover.IsUnset then
    self.Cover := FindSongFile(Path, '*[CO].jpg');

  //Check if all Required Values are given
  if (Done <> 15) then
  begin
    Result := false;
    if (Done and 8) = 0 then      //No BPM Flag
      Log.LogError('BPM tag missing: ' + FullFileName)
    else if (Done and 4) = 0 then //No MP3 Flag
      Log.LogError('MP3 tag/file missing: ' + FullFileName)
    else if (Done and 2) = 0 then //No Artist Flag
      Log.LogError('Artist tag missing: ' + FullFileName)
    else if (Done and 1) = 0 then //No Title Flag
      Log.LogError('Title tag missing: ' + FullFileName)
    else //unknown Error
      Log.LogError('File incomplete or not Ultrastar txt (B - '+ inttostr(Done) +'): ' + FullFileName);
  end;
end;

function  TSong.GetErrorLineNo: integer;
begin
  if (LastError='ERROR_CORRUPT_SONG_ERROR_IN_LINE') then
    Result := FileLineNo
  else
    Result := -1;
end;

function TSong.Solmizate(Note: integer; Type_: integer): string;
begin
  case (Type_) of
    1:  // european
      begin
        case (Note mod 12) of
          0..1:   Result := ' do ';
          2..3:   Result := ' re ';
          4:      Result := ' mi ';
          5..6:   Result := ' fa ';
          7..8:   Result := ' sol ';
          9..10:  Result := ' la ';
          11:     Result := ' si ';
        end;
      end;
    2:  // japanese
      begin
        case (Note mod 12) of
          0..1:   Result := ' do ';
          2..3:   Result := ' re ';
          4:      Result := ' mi ';
          5..6:   Result := ' fa ';
          7..8:   Result := ' so ';
          9..10:  Result := ' la ';
          11:     Result := ' shi ';
        end;
      end;
    3:  // american
      begin
        case (Note mod 12) of
          0..1:   Result := ' do ';
          2..3:   Result := ' re ';
          4:      Result := ' mi ';
          5..6:   Result := ' fa ';
          7..8:   Result := ' sol ';
          9..10:  Result := ' la ';
          11:     Result := ' ti ';
        end;
      end;
  end; // case
end;

procedure TSong.ParseNote(LineNumber: integer; TypeP: char; StartP, DurationP, NoteP: integer; LyricS: UTF8String);
begin
  if (Ini.Solmization <> 0) then
    LyricS := Solmizate(NoteP, Ini.Solmization);

  with Lines[LineNumber].Line[Lines[LineNumber].High] do
  begin
    SetLength(Note, Length(Note) + 1);
    HighNote := High(Note);

    Note[HighNote].Start := StartP;
    if HighNote = 0 then
    begin
      if Lines[LineNumber].Number = 1 then
        Start := -100;
        //Start := Note[HighNote].Start;
    end;

    Note[HighNote].Length := DurationP;

    // back to the normal system with normal, golden and now freestyle notes
    case TypeP of
      'F':  Note[HighNote].NoteType := ntFreestyle;
      ':':  Note[HighNote].NoteType := ntNormal;
      '*':  Note[HighNote].NoteType := ntGolden;
    end;

    //add this notes value ("notes length" * "notes scorefactor") to the current songs entire value
    Inc(Lines[LineNumber].ScoreValue, Note[HighNote].Length * ScoreFactor[Note[HighNote].NoteType]);

    //and to the current lines entire value
    Inc(TotalNotes, Note[HighNote].Length * ScoreFactor[Note[HighNote].NoteType]);


    Note[HighNote].Tone := NoteP;

    //if a note w/ a deeper pitch then the current basenote is found
    //we replace the basenote w/ the current notes pitch
    if Note[HighNote].Tone < BaseNote then
      BaseNote := Note[HighNote].Tone;

    DecodeStringUTF8(LyricS, Note[HighNote].Text, Encoding);
    Lyric := Lyric + Note[HighNote].Text;

    End_ := Note[HighNote].Start + Note[HighNote].Length;
  end; // with
end;

procedure TSong.NewSentence(LineNumberP: integer; Param1, Param2: integer);
var
  I: integer;
begin

  if (Lines[LineNumberP].Line[Lines[LineNumberP].High].HighNote  <> -1) then
  begin //create a new line
    SetLength(Lines[LineNumberP].Line, Lines[LineNumberP].Number + 1);
    Inc(Lines[LineNumberP].High);
    Inc(Lines[LineNumberP].Number);
  end
  else
  begin //use old line if it there were no notes added since last call of NewSentence
    Log.LogError('Error loading Song, sentence w/o note found in line ' +
                 InttoStr(FileLineNo) + ': ' + Filename.ToNative);
  end;

  Lines[LineNumberP].Line[Lines[LineNumberP].High].HighNote := -1;

  //set the current lines value to zero
  //it will be incremented w/ the value of every added note
  Lines[LineNumberP].Line[Lines[LineNumberP].High].TotalNotes := 0;

  //basenote is the pitch of the deepest note, it is used for note drawing.
  //if a note with a less value than the current sentences basenote is found,
  //basenote will be set to this notes pitch. Therefore the initial value of
  //this field has to be very high.
  Lines[LineNumberP].Line[Lines[LineNumberP].High].BaseNote := High(Integer);


  if self.Relative then
  begin
    Lines[LineNumberP].Line[Lines[LineNumberP].High].Start := Param1;
    Rel[LineNumberP] := Rel[LineNumberP] + Param2;
  end
  else
    Lines[LineNumberP].Line[Lines[LineNumberP].High].Start := Param1;

  Lines[LineNumberP].Line[Lines[LineNumberP].High].LastLine := false;
end;

procedure TSong.Clear();
begin
  //Main Information
  Title  := '';
  Artist := '';

  //Sortings:
  Genre    := 'Unknown';
  Edition  := 'Unknown';
  Language := 'Unknown'; //Language Patch

  // set to default encoding
  Encoding := DEFAULT_ENCODING;

  //Required Information
  Mp3    := PATH_NONE;
  SetLength(BPM, 0);

  GAP    := 0;
  Start  := 0;
  Finish := 0;

  //Additional Information
  Background := PATH_NONE;
  Cover      := PATH_NONE;
  Video      := PATH_NONE;
  VideoGAP   := 0;
  NotesGAP   := 0;
  Resolution := 4;
  Creator    := '';

  Relative := false;
end;

function TSong.Analyse(): boolean;
var
  SongFile: TTextFileStream;
begin
  Result := false;

  //Reset LineNo
  FileLineNo := 0;

  //Open File and set File Pointer to the beginning
  SongFile := TMemTextFileStream.Create(Self.Path.Append(Self.FileName), fmOpenRead);
  try
    //Clear old Song Header
    Self.clear;

    //Read Header
    Result := Self.ReadTxTHeader(SongFile)
  finally
    SongFile.Free;
  end;
end;


function TSong.AnalyseXML(): boolean;

begin
  Result := false;

  //Reset LineNo
  FileLineNo := 0;

  //Clear old Song Header
  self.clear;

  //Read Header
  Result := self.ReadXMLHeader( FileName );

end;

end.