- encodings seperated to multiple files located in "encoding"

git-svn-id: svn://svn.code.sf.net/p/ultrastardx/svn/branches/experimental@1857 b956fd51-792f-4845-bead-9b4dfca2ff2c

1 files changed, 136 insertions, 137 deletions

diff --git a/unicode/src/base/UTextEncoding.pas b/unicode/src/base/UTextEncoding.pas
index 61cd0098..966064c0 100644
--- a/unicode/src/base/UTextEncoding.pas
+++ b/unicode/src/base/UTextEncoding.pas
@@ -34,181 +34,164 @@ interface
 {$I switches.inc}
 
 uses
-  SysUtils,
-  StrUtils;
+  SysUtils;
 
 type
   TEncoding = (
-    encCP1250,  // Windows-1250 Central/Eastern Europe (used by Ultrastar)
-    encCP1252,  // Windows-1252 Western Europe (used by UltraStar Deluxe < 1.1)
+    encLocale,  // current locale (needs cwstring on linux)
     encUTF8,    // UTF-8
-    encLocale   // current locale (needs cwstring on linux)
-  );
-
-const
-  EncodingNames: array[TEncoding] of AnsiString = (
-    'CP1250',
-    'CP1252',
-    'UTF8',
-    'LOCALE'
+    encCP1250,  // Windows-1250 Central/Eastern Europe (used by Ultrastar)
+    encCP1252   // Windows-1252 Western Europe (used by UltraStar Deluxe < 1.1)
   );
 
 const
   UTF8_BOM: UTF8String = #$EF#$BB#$BF;
 
 {**
- * Changes encoding of string Src with encoding SrcEncoding to UTF-16
- * If SrcEncoding is encUnknown the result is undefined.
+ * Decodes Src encoded in SrcEncoding to a UTF-16 or UTF-8 encoded Dst string.
+ * Returns true if the conversion was successful.
  *}
-function RecodeStringWide(const Src: string; SrcEncoding: TEncoding): WideString;
+function DecodeString(const Src: AnsiString; out Dst: WideString; SrcEncoding: TEncoding): boolean; overload;
+function DecodeString(const Src: AnsiString; SrcEncoding: TEncoding): WideString; overload;
+function DecodeStringUTF8(const Src: AnsiString; out Dst: UTF8String; SrcEncoding: TEncoding): boolean; overload;
+function DecodeStringUTF8(const Src: AnsiString; SrcEncoding: TEncoding): UTF8String; overload;
 
 {**
- * Changes encoding of string Src with encoding SrcEncoding to UTF-8.
- * If SrcEncoding is encUnknown the result is undefined.
+ * Encodes the UTF-16 or UTF-8 encoded Src string to Dst using DstEncoding
+ * Returns true if the conversion was successful.
  *}
-function RecodeStringUTF8(const Src: string; SrcEncoding: TEncoding): UTF8String;
+function EncodeString(const Src: WideString; out Dst: AnsiString; DstEncoding: TEncoding): boolean; overload;
+function EncodeString(const Src: WideString; DstEncoding: TEncoding): AnsiString; overload;
+function EncodeStringUTF8(const Src: UTF8String; out Dst: AnsiString; DstEncoding: TEncoding): boolean; overload;
+function EncodeStringUTF8(const Src: UTF8String; DstEncoding: TEncoding): AnsiString; overload;
 
 {**
  * If Text starts with an UTF-8 BOM, the BOM is removed and true will
  * be returned.
  *}
-function CheckReplaceUTF8BOM(var Text: string): boolean;
+function CheckReplaceUTF8BOM(var Text: AnsiString): boolean;
 
 {**
  * Parses an encoding string to its TEncoding equivalent.
  * Surrounding whitespace and dashes ('-') are removed, the upper-cased
  * resulting value is then compared with TEncodingNames.
- * If the encoding was not found, the result is set to the Default encoding. 
+ * If the encoding was not found, the result is set to the Default encoding.
  *}
 function ParseEncoding(const EncodingStr: AnsiString; Default: TEncoding): TEncoding;
 
+{**
+ * Returns the name of an encoding.
+ *}
+function EncodingName(Encoding: TEncoding): AnsiString;
+
 implementation
 
+uses
+  StrUtils,
+  UUnicodeUtils;
+
 type
-  TConversionTable = array[0..127] of WideChar;
+  IEncoder = interface
+    function GetName(): AnsiString;
+    function Encode(const InStr: UCS4String; out OutStr: AnsiString): boolean;
+    function Decode(const InStr: AnsiString; out OutStr: UCS4String): boolean;
+  end;
+
+  TEncoder = class(TInterfacedObject, IEncoder)
+  public
+    function GetName(): AnsiString; virtual; abstract;
+    function Encode(const InStr: UCS4String; out OutStr: AnsiString): boolean; virtual; abstract;
+    function Decode(const InStr: AnsiString; out OutStr: UCS4String): boolean; virtual; abstract;
+  end;
+
+  TSingleByteEncoder = class(TEncoder)
+  public
+    function Encode(const InStr: UCS4String; out OutStr: AnsiString): boolean; override;
+    function Decode(const InStr: AnsiString; out OutStr: UCS4String): boolean; override;
+    function DecodeChar(InChr: AnsiChar; out OutChr: UCS4Char): boolean; virtual; abstract;
+    function EncodeChar(InChr: UCS4Char; out OutChr: AnsiChar): boolean; virtual; abstract;
+  end;
 
 const
-  // Windows-1250 Central/Eastern Europe (used by Ultrastar)
-  CP1250Table: TConversionTable = (
-    { $80 }
-    #$20AC,     #0, #$201A,     #0, #$201E, #$2026, #$2020, #$2021,
-        #0, #$2030, #$0160, #$2039, #$015A, #$0164, #$017D, #$0179,
-    { $90 }
-        #0, #$2018, #$2019, #$201C, #$201D, #$2022, #$2013, #$2014,
-        #0, #$2122, #$0161, #$203A, #$015B, #$0165, #$017E, #$017A,
-    { $A0 }
-    #$00A0, #$02C7, #$02D8, #$0141, #$00A4, #$0104, #$00A6, #$00A7,
-    #$00A8, #$00A9, #$015E, #$00AB, #$00AC, #$00AD, #$00AE, #$017B,
-    { $B0 }
-    #$00B0, #$00B1, #$02DB, #$0142, #$00B4, #$00B5, #$00B6, #$00B7,
-    #$00B8, #$0105, #$015F, #$00BB, #$013D, #$02DD, #$013E, #$017C,
-    { $C0 }
-    #$0154, #$00C1, #$00C2, #$0102, #$00C4, #$0139, #$0106, #$00C7,
-    #$010C, #$00C9, #$0118, #$00CB, #$011A, #$00CD, #$00CE, #$010E,
-    { $D0 }
-    #$0110, #$0143, #$0147, #$00D3, #$00D4, #$0150, #$00D6, #$00D7,
-    #$0158, #$016E, #$00DA, #$0170, #$00DC, #$00DD, #$0162, #$00DF,
-    { $E0 }
-    #$0155, #$00E1, #$00E2, #$0103, #$00E4, #$013A, #$0107, #$00E7,
-    #$010D, #$00E9, #$0119, #$00EB, #$011B, #$00ED, #$00EE, #$010F,
-    { $F0 }
-    #$0111, #$0144, #$0148, #$00F3, #$00F4, #$0151, #$00F6, #$00F7,
-    #$0159, #$016F, #$00FA, #$0171, #$00FC, #$00FD, #$0163, #$02D9
-  );
+  ERROR_CHAR = '?';
 
-  // Windows-1252 Western Europe (used by UltraStar Deluxe < 1.1)
-  CP1252Table: TConversionTable = (
-    { $80 }
-    #$20AC,     #0, #$201A, #$0192, #$201E, #$2026, #$2020, #$2021,
-    #$02C6, #$2030, #$0160, #$2039, #$0152,     #0, #$017D,     #0,
-    { $90 }
-        #0, #$2018, #$2019, #$201C, #$201D, #$2022, #$2013, #$2014,
-    #$02DC, #$2122, #$0161, #$203A, #$0153,     #0, #$017E, #$0178,
-    { $A0 }
-    #$00A0, #$00A1, #$00A2, #$00A3, #$00A4, #$00A5, #$00A6, #$00A7,
-    #$00A8, #$00A9, #$00AA, #$00AB, #$00AC, #$00AD, #$00AE, #$00AF,
-    { $B0 }
-    #$00B0, #$00B1, #$00B2, #$00B3, #$00B4, #$00B5, #$00B6, #$00B7,
-    #$00B8, #$00B9, #$00BA, #$00BB, #$00BC, #$00BD, #$00BE, #$00BF,
-    { $C0 }
-    #$00C0, #$00C1, #$00C2, #$00C3, #$00C4, #$00C5, #$00C6, #$00C7,
-    #$00C8, #$00C9, #$00CA, #$00CB, #$00CC, #$00CD, #$00CE, #$00CF,
-    { $D0 }
-    #$00D0, #$00D1, #$00D2, #$00D3, #$00D4, #$00D5, #$00D6, #$00D7,
-    #$00D8, #$00D9, #$00DA, #$00DB, #$00DC, #$00DD, #$00DE, #$00DF,
-    { $E0 }
-    #$00E0, #$00E1, #$00E2, #$00E3, #$00E4, #$00E5, #$00E6, #$00E7,
-    #$00E8, #$00E9, #$00EA, #$00EB, #$00EC, #$00ED, #$00EE, #$00EF,
-    { $F0 }
-    #$00F0, #$00F1, #$00F2, #$00F3, #$00F4, #$00F5, #$00F6, #$00F7,
-    #$00F8, #$00F9, #$00FA, #$00FB, #$00FC, #$00FD, #$00FE, #$00FF
-  );
+var
+  Encoders: array[TEncoding] of IEncoder;
 
-{**
- * Internal conversion function
- *}
-function Convert(const Src: string; const Table: TConversionTable): WideString;
+function TSingleByteEncoder.Encode(const InStr: UCS4String; out OutStr: AnsiString): boolean;
 var
-  SrcPos, DstPos: integer;
+  I: integer;
 begin
-  SetLength(Result, Length(Src));
-  DstPos := 1;
-  for SrcPos := 1 to Length(Src) do
+  SetLength(OutStr, LengthUCS4(InStr));
+  Result := true;
+  for I := 1 to Length(OutStr) do
   begin
-    if (Src[SrcPos] < #128) then
-    begin
-      // copy ASCII char
-      // Important: the Ord() is necessary to prevent FPC from an automatic
-      // encoding conversion (using the local codepage). Delphi does not perform
-      // such a conversion.
-      Result[DstPos] := WideChar(Ord(Src[SrcPos]));
-      Inc(DstPos);
-    end
-    else
-    begin
-      // look-up char
-      Result[DstPos] := Table[Ord(Src[SrcPos]) - 128];
-      // ignore invalid characters
-      if (Result[DstPos] <> #0) then
-        Inc(DstPos);
-    end;
+    if (not EncodeChar(InStr[I-1], OutStr[I])) then
+      Result := false;
   end;
-  SetLength(Result, DstPos-1);
 end;
 
-function RecodeStringWide(const Src: string; SrcEncoding: TEncoding): WideString;
+function TSingleByteEncoder.Decode(const InStr: AnsiString; out OutStr: UCS4String): boolean;
+var
+  I: integer;
 begin
-  case SrcEncoding of
-    encCP1250:
-      Result := Convert(Src, CP1250Table);
-    encCP1252:
-      Result := Convert(Src, CP1252Table);
-    encUTF8:
-      Result := UTF8Decode(Src);
-    encLocale:
-      Result := UTF8Decode(AnsiToUtf8(Src));
-    else
-      Result := '';
+  SetLength(OutStr, Length(InStr)+1);
+  Result := true;
+  for I := 1 to Length(InStr) do
+  begin
+    if (not DecodeChar(InStr[I], OutStr[I-1])) then
+      Result := false;
   end;
+  OutStr[High(OutStr)] := 0;
 end;
 
-function RecodeStringUTF8(const Src: string; SrcEncoding: TEncoding): UTF8String;
+function DecodeString(const Src: AnsiString; out Dst: WideString; SrcEncoding: TEncoding): boolean;
+var
+  DstUCS4: UCS4String;
 begin
-  case SrcEncoding of
-    encCP1250:
-      Result := UTF8Encode(Convert(Src, CP1250Table));
-    encCP1252:
-      Result := UTF8Encode(Convert(Src, CP1252Table));
-    encUTF8:
-      Result := Src;
-    encLocale:
-      Result := AnsiToUtf8(Src);
-    else
-      Result := '';
-  end;
+  Result := Encoders[SrcEncoding].Decode(Src, DstUCS4);
+  Dst := UCS4StringToWideString(DstUCS4);
 end;
 
-function CheckReplaceUTF8BOM(var Text: string): boolean;
+function DecodeString(const Src: AnsiString; SrcEncoding: TEncoding): WideString;
+begin
+  DecodeString(Src, Result, SrcEncoding);
+end;
+
+function DecodeStringUTF8(const Src: AnsiString; out Dst: UTF8String; SrcEncoding: TEncoding): boolean;
+var
+  DstUCS4: UCS4String;
+begin
+  Result := Encoders[SrcEncoding].Decode(Src, DstUCS4);
+  Dst := UCS4ToUTF8String(DstUCS4);
+end;
+
+function DecodeStringUTF8(const Src: AnsiString; SrcEncoding: TEncoding): UTF8String;
+begin
+  DecodeStringUTF8(Src, Result, SrcEncoding);
+end;
+
+function EncodeString(const Src: WideString; out Dst: AnsiString; DstEncoding: TEncoding): boolean;
+begin
+  Result := Encoders[DstEncoding].Encode(WideStringToUCS4String(Src), Dst);
+end;
+
+function EncodeString(const Src: WideString; DstEncoding: TEncoding): AnsiString;
+begin
+  EncodeString(Src, Result, DstEncoding);
+end;
+
+function EncodeStringUTF8(const Src: UTF8String; out Dst: AnsiString; DstEncoding: TEncoding): boolean;
+begin
+  Result := Encoders[DstEncoding].Encode(UTF8ToUCS4String(Src), Dst);
+end;
+
+function EncodeStringUTF8(const Src: UTF8String; DstEncoding: TEncoding): AnsiString;
+begin
+  EncodeStringUTF8(Src, Result, DstEncoding);
+end;
+
+function CheckReplaceUTF8BOM(var Text: AnsiString): boolean;
 begin
   if AnsiStartsStr(UTF8_BOM, Text) then
   begin
@@ -221,20 +204,36 @@ end;
 
 function ParseEncoding(const EncodingStr: AnsiString; Default: TEncoding): TEncoding;
 var
-  PrepStr: string; // prepared encoding string
+  PrepStr: AnsiString; // prepared encoding string
   Encoding: TEncoding;
 begin
   // remove surrounding whitespace, replace dashes, to upper case
-  PrepStr := UpperCase(AnsiReplaceStr(Trim(EncodingStr), '-', ''));

-  for Encoding := Low(EncodingNames) to High(EncodingNames) do

-  begin

-    if (EncodingNames[Encoding] = PrepStr) then

-    begin

-      Result := Encoding;

-      Exit;

+  PrepStr := UpperCase(AnsiReplaceStr(Trim(EncodingStr), '-', ''));
+  for Encoding := Low(TEncoding) to High(TEncoding) do
+  begin
+    if (Encoders[Encoding].GetName() = PrepStr) then
+    begin
+      Result := Encoding;
+      Exit;
     end;

   end;

-  Result := Default;

+  Result := Default;
+end;
+
+function EncodingName(Encoding: TEncoding): AnsiString;
+begin
+  Result := Encoders[Encoding].GetName();
 end;
 
+{$I ../encoding/Locale.inc}
+{$I ../encoding/UTF8.inc}
+{$I ../encoding/CP1250.inc}
+{$I ../encoding/CP1252.inc}
+
+initialization
+  Encoders[encLocale] := TEncoderLocale.Create;
+  Encoders[encUTF8]   := TEncoderUTF8.Create;
+  Encoders[encCP1250] := TEncoderCP1250.Create;
+  Encoders[encCP1252] := TEncoderCP1252.Create;
+
 end.