unit fpsNumFormatParser;

{$ifdef fpc}
  {$mode delphi}
{$endif}

interface

uses
  SysUtils, fpspreadsheet;


const
  psOK = 0;
  psErrNoValidColorIndex = 1;
  psErrNoValidCompareNumber = 2;
  psErrUnknownInfoInBrackets = 3;
  psErrConditionalFormattingNotSupported = 4;
  psErrNoUsableFormat = 5;
  psErrNoValidNumberFormat = 6;
  psErrNoValidDateTimeFormat = 7;

{ TsNumFormatParser }

type
  TsCompareOperation = (coNotUsed,
    coEqual, coNotEqual, coLess, coGreater, coLessEqual, coGreaterEqual
  );

  TsNumFormatSection = record
    FormatString: String;
    CompareOperation: TsCompareOperation;
    CompareValue: Double;
    Color: TsColor;
    CountryCode: String;
    CurrencySymbol: String;
    Decimals: Byte;
    NumFormat: TsNumberFormat;
  end;

  TsNumFormatParser = class
  private
    FWorkbook: TsWorkbook;
    FCurrent: PChar;
    FStart: PChar;
    FEnd: PChar;
    FCurrSection: Integer;
    FSections: array of TsNumFormatSection;
    FFormatSettings: TFormatSettings;
    FFormatString: String;
    FStatus: Integer;
    function GetParsedSectionCount: Integer;
    function GetParsedSections(AIndex: Integer): TsNumFormatSection;

  protected
    procedure AddChar(AChar: Char);
    procedure AddSection;
    procedure AnalyzeBracket(const AValue: String);
    procedure AnalyzeText(const AValue: String);
    procedure CheckSections;
    procedure Parse(const AFormatString: String);
    procedure ScanAMPM(var s: String);
    procedure ScanBrackets;
    procedure ScanDateTime;
    procedure ScanDateTimeParts(TestToken, Replacement: Char; var s: String);
    procedure ScanFormat;
    procedure ScanNumber;
    procedure ScanText;

  public
    constructor Create(AWorkbook: TsWorkbook; const AFormatString: String);
    destructor Destroy; override;
    property FormatString: String read FFormatString;
    property ParsedSectionCount: Integer read GetParsedSectionCount;
    property ParsedSections[AIndex: Integer]: TsNumFormatSection read GetParsedSections;
    property Status: Integer read FStatus;
  end;

implementation

uses
  fpsutils;

const
  COMPARE_STR: array[TsCompareOperation] of string = (
    '', '=', '<>', '<', '>', '<=', '>'
  );

{ TsNumFormatParser }

constructor TsNumFormatParser.Create(AWorkbook: TsWorkbook;
  const AFormatString: String);
begin
  inherited Create;
  FWorkbook := AWorkbook;
  FFormatSettings := DefaultFormatSettings;
  FFormatSettings.DecimalSeparator := '.';
  FFormatSettings.ThousandSeparator := ',';
  Parse(AFormatString);
end;

destructor TsNumFormatParser.Destroy;
begin
  FSections := nil;
  inherited Destroy;
end;

procedure TsNumFormatParser.AddChar(AChar: Char);
begin
  with FSections[FCurrSection] do
    FormatString := FormatString + AChar;
end;

procedure TsNumFormatParser.AddSection;
begin
  FCurrSection := Length(FSections);
  SetLength(FSections, FCurrSection + 1);
  with FSections[FCurrSection] do begin
    FormatString := '';
    CompareOperation := coNotUsed;
    CompareValue := 0.0;
    Color := scBlack;
    CountryCode := '';
    CurrencySymbol := '';
    Decimals := 0;
    NumFormat := nfGeneral;
  end;
end;

procedure TsNumFormatParser.AnalyzeBracket(const AValue: String);
var
  lValue: String;
  n: Integer;
begin
  lValue := lowercase(AValue);
  // Colors
  if lValue = 'red' then
    FSections[FCurrSection].Color := scRed
  else
  if lValue = 'black' then
    FSections[FCurrSection].Color := scBlack
  else
  if lValue = 'blue' then
    FSections[FCurrSection].Color := scBlue
  else
  if lValue = 'white' then
    FSections[FCurrSection].Color := scWhite
  else
  if lValue = 'green' then
    FSections[FCurrSection].Color := scGreen
  else
  if lValue = 'cyan' then
    FSections[FCurrSection].Color := scCyan
  else
  if lValue = 'magenta' then
    FSections[FCurrSection].Color := scMagenta
  else
  if copy(lValue, 1, 5) = 'color' then begin
    lValue := copy(lValue, 6, Length(lValue));
    if not TryStrToInt(trim(lValue), n) then begin
      FStatus := psErrNoValidColorIndex;
      exit;
    end;
    FSections[FCurrSection].Color := n;
  end
  else
  // Conditions
  if lValue[1] in ['=', '<', '>'] then begin
    n := 1;
    case lValue[1] of
      '=': FSections[FCurrSection].CompareOperation := coEqual;
      '<': case lValue[2] of
             '>': begin FSections[FCurrSection].CompareOperation := coNotEqual; inc(n); end;
             '=': begin FSections[FCurrSection].CompareOperation := coLessEqual; inc(n); end;
             else FSections[FCurrSection].CompareOperation := coLess;
           end;
      '>': case lValue[2] of
             '=': begin FSections[FCurrSection].CompareOperation := coGreaterEqual; inc(n); end;
             else FSections[FCurrSection].CompareOperation := coGreater;
           end;
    end;
    Delete(lValue, 1, n);
    if not TryStrToFloat(trim(lValue), FSections[FCurrSection].CompareValue) then
      FStatus := psErrNoValidCompareNumber;
  end else
  // Locale information
  if lValue[1] = '$' then begin
    FSections[FCurrSection].CountryCode := Copy(AValue, 2, Length(AValue));
  end else
    FStatus := psErrUnknownInfoInBrackets;
end;

procedure TsNumFormatParser.AnalyzeText(const AValue: String);
var
  uValue: String;
begin
  uValue := Uppercase(AValue);
  if (uValue = '$') or (uValue = 'USD') or (uValue = '€') or (uValue = 'EUR') or
     (uValue = '£') or (uValue = 'GBP') or (uValue = '¥') or (uValue = 'JPY')
  then
    FSections[FCurrSection].CurrencySymbol := AValue;
end;

procedure TsNumFormatParser.CheckSections;
var
  i: Integer;
  ns: Integer;
  s: String;
begin
  ns := Length(FSections);

  for i:=0 to ns-1 do begin
    if FSections[i].FormatString = '' then
      FSections[i].NumFormat := nfGeneral;

    if (FSections[i].CurrencySymbol <> '') and (FSections[i].NumFormat = nfFixedTh) then
      FSections[i].NumFormat := nfCurrency;

    if FSections[i].CompareOperation <> coNotUsed then begin
      FStatus := psErrConditionalFormattingNotSupported;
      exit;
    end;

    case FSections[i].NumFormat of
      nfGeneral, nfFixed, nfFixedTh, nfPercentage, nfExp, nfSci, nfCurrency:
        try
          s := FormatFloat(FSections[i].FormatString, 1.0, FWorkBook.FormatSettings);
        except
          FStatus := psErrNoValidNumberFormat;
          exit;
        end;

      nfShortDateTime, nfShortDate, nfShortTime, nfShortTimeAM,
      nfLongDate, nfLongTime, nfLongTimeAM, nfFmtDateTime:
        try
          s := FormatDateTimeEx(FSections[i].FormatString, now(), FWorkbook.FormatSettings);
        except
          FStatus := psErrNoValidDateTimeFormat;
          exit;
        end;
    end;
  end;

  if ns = 2 then
    FFormatString := Format('%s;%s;%s', [
      FSections[0].FormatString,
      FSections[1].FormatString,
      FSections[0].FormatString  // make sure that fpc understands the "zero"
    ])
  else
  if ns > 0 then begin
    FFormatString := FSections[0].FormatString;
    for i:=1 to ns-1 do
      FFormatString := Format('%s;%s', [FFormatString, FSections[i].FormatString]);
  end else
    FStatus := psErrNoUsableFormat;
end;

{
function TsNumFormatParser.GetNumFormat: TsNumberFormat;
var
  i: Integer;
begin
  if FStatus <> psOK then
    Result := nfGeneral
  else
  if (FSections[0].NumFormat = nfCurrency) and (FSections[1].NumFormat = nfCurrency) and
     (FSections[2].NumFormat = nfCurrency)
  then begin
    if (FSections[1].Color = scNotDefined) then begin
      if (FSections[2].FormatString = '-') then
        Result := nfCurrencyDash
      else
        Result := nfCurrency;
    end else
    if FSections[1].Color = scRed then begin
      if (FSections[2].Formatstring = '-') then
        Result := nfCurrencyDashRed
      else
        Result := nfCurrencyRed;
    end;
  end else
    Result := FSections[0].NumFormat;
end;
}

function TsNumFormatParser.GetParsedSectionCount: Integer;
begin
  Result := Length(FSections);
end;

function TsNumFormatParser.GetParsedSections(AIndex: Integer): TsNumFormatSection;
begin
  Result := FSections[AIndex];
end;

procedure TsNumFormatParser.Parse(const AFormatString: String);
var
  token: Char;
begin
  FStatus := psOK;
  AddSection;
  FStart := @AFormatString[1];
  FEnd := FStart + Length(AFormatString) - 1;
  FCurrent := FStart;
  while (FCurrent <= FEnd) and (FStatus = psOK) do begin
    token := FCurrent^;
    case token of
      '[': ScanBrackets;
      ';': AddSection;
      else ScanFormat;
    end;
    inc(FCurrent);
  end;
  CheckSections;
end;

{ Extracts the text between square brackets --> AnalyzeBracket }
procedure TsNumFormatParser.ScanBrackets;
var
  s: String;
  token: Char;
begin
  inc(FCurrent);  // cursor stands at '['
  while (FCurrent <= FEnd) and (FStatus = psOK) do begin
    token := FCurrent^;
    case token of
      ']': begin
             AnalyzeBracket(s);
             break;
           end;
      else
           s := s + token;
    end;
    inc(FCurrent);
  end;
end;

procedure TsNumFormatParser.ScanDateTime;
var
  token: Char;
  done: Boolean;
  s: String;
  i: Integer;
  nf: TsNumberFormat;
  partStr: String;
  isTime: Boolean;
  isAMPM: Boolean;
begin
  done := false;
  s := '';
  isTime := false;
  isAMPM := false;

  while (FCurrent <= FEnd) and (FStatus = psOK) and (not done) do begin
    token := FCurrent^;
    case token of
      '\'       : begin
                    inc(FCurrent);
                    token := FCurrent^;
                    s := s + token;
                  end;
      'Y', 'y'  : begin
                    ScanDateTimeParts(token, token, s);
                    isTime := false;
                  end;
      'M', 'm'  : if isTime then    // help fpc to separate "month" and "minute"
                    ScanDateTimeParts(token, 'n', s)
                  else   // both "month" and "minute" work in fpc to some degree
                    ScanDateTimeParts(token, token, s);
      'D', 'd'  : begin
                    ScanDateTimeParts(token, token, s);
                    isTime := false;
                  end;
      'H', 'h'  : begin
                    ScanDateTimeParts(token, token, s);
                    isTime := true;
                  end;
      'S', 's'  : begin
                    ScanDateTimeParts(token, token, s);
                    isTime := true;
                  end;
      '/', ':', '.', ']', '[', ' '
                : s := s + token;
      '0'       : ScanDateTimeParts(token, 'z', s);
      'A', 'a'  : begin
                    ScanAMPM(s);
                    isAMPM := true;
                  end;
      else        begin
                    done := true;
                    dec(FCurrent);
                    // char pointer must be at end of date/time mask.
                  end;
    end;
    if not done then inc(FCurrent);
  end;

  FSections[FCurrSection].FormatString := FSections[FCurrSection].FormatString + s;
  s := FSections[FCurrSection].FormatString;

  // Check format
  try
    if s <> '' then begin
      FormatDateTime(s, now);
      // !!!! MODIFY TO USE EXTENDED SYNTAX !!!!!

      if s = FWorkbook.FormatSettings.LongDateFormat then
        nf := nfLongDate
      else
      if s = FWorkbook.FormatSettings.ShortDateFormat then
        nf := nfShortDate
      else
      if s = FWorkbook.FormatSettings.LongTimeFormat then
        nf := nfLongTime
      else
      if s = FWorkbook.FormatSettings.ShortTimeFormat then
        nf := nfShortTime
      else
        nf := nfFmtDateTime;
      FSections[FCurrSection].NumFormat := nf;
    end;

  except
    FStatus := psErrNoValidDateTimeFormat;
  end;
end;

procedure TsNumFormatParser.ScanAMPM(var s: String);
var
  token: Char;
begin
  while (FCurrent <= FEnd) do begin
    token := FCurrent^;
    if token in ['A', 'a', 'P', 'p', 'm', 'M', '/'] then
      s := s + token
    else begin
      dec(FCurrent);
      exit;
    end;
    inc(FCurrent);
  end;
end;

procedure TsNumFormatParser.ScanDateTimeParts(TestToken, Replacement: Char;
  var s: String);
var
  token: Char;
begin
  s := s + Replacement;
  while (FCurrent <= FEnd) do begin
    inc(FCurrent);
    token := FCurrent^;
    if token = TestToken then
      s := s + Replacement
    else begin
      dec(FCurrent);
      break;
    end;
  end;
end;

procedure TsNumFormatParser.ScanFormat;
var
  token: Char;
  done: Boolean;
begin
  done := false;
  while (FCurrent <= FEnd) and (FStatus = psOK) and (not done) do begin
    token := FCurrent^;
    case token of
      // Strip Excel's formatting symbols
      '\', '*'               : ;
      '_'                    : inc(FCurrent);
      '"'                    : begin
                                 inc(FCurrent);
                                 ScanText;
                               end;
      '0', '#', '.', ',', '-': ScanNumber;
      'y', 'Y', 'm', 'M',
      'd', 'D', 'h', 's', '[': ScanDateTime;
      ' '                    : AddChar(token);
      ';'                    : begin
                                 done := true;
                                 dec(FCurrent);
                                 // Cursor must stay on the ";"
                               end;
    end;
    if not done then inc(FCurrent);
  end;
end;

procedure TsNumFormatParser.ScanNumber;
var
  token: Char;
  done: Boolean;
  countdecs: Boolean;
  s: String;
  hasThSep: Boolean;
  isExp: Boolean;
  isSci: Boolean;
  hasHash: Boolean;
  hasPerc: Boolean;
  nf: TsNumberFormat;
begin
  countdecs := false;
  done := false;
  hasThSep := false;
  hasHash := false;
  hasPerc := false;
  isExp := false;
  isSci := false;
  s := '';
  while (FCurrent <= FEnd) and (FStatus = psOK) and (not done) do begin
    token := FCurrent^;
    case token of
      ',': begin
             hasThSep := true;
             s := s + token;
           end;
      '.': begin
             countdecs := true;
             FSections[FCurrSection].Decimals := 0;
             s := s + token;
           end;
      '0': begin
             if countdecs then inc(FSections[FCurrSection].Decimals);
             s := s + token;
           end;
      'E', 'e':
           begin
             if hasHash and countdecs then isSci := true else isExp := true;
             countdecs := false;
             s := s + token;
           end;
      '+', '-':
           s := s + token;
      '#': begin
             hasHash := true;
             countdecs := false;
             s := s + token;
           end;
      '%': begin
             hasPerc := true;
             s := s + token;
           end;
      else begin
             done := true;
             dec(FCurrent);
           end;
    end;
    if not done then
      inc(FCurrent);
  end;

  if s <> '' then begin
    if isExp then
      nf := nfExp
    else if isSci then
      nf := nfSci
    else if hasPerc then
      nf := nfPercentage
    else if hasThSep then
      nf := nfFixedTh
    else
      nf := nfFixed;
  end else
    nf := nfGeneral;

  FSections[FCurrSection].NumFormat := nf;
  FSections[FCurrSection].FormatString := FSections[FCurrSection].FormatString + s;
end;

{ Scans a text in quotation marks. Tries to interpret the text as a currency
  symbol (--> AnalyzeText) }
procedure TsNumFormatParser.ScanText;
var
  token: Char;
  done: Boolean;
  s: String;
begin
  done := false;
  s := '';
  while (FCurrent <= FEnd) and (FStatus = psOK) and not done do begin
    token := FCurrent^;
    if token = '"' then begin
      done := true;
      AnalyzeText(s);
    end else begin
      s := s + token;
      inc(FCurrent);
    end;
  end;
  FSections[FCurrSection].FormatString := Format('%s"%s"',
    [FSections[FCurrSection].FormatString, s]);
end;

end.