//==============================================================================
// intextstream.hpp
//	Generic input text stream.
//
// Notice
//	Copyright ©2008 by David R. Tribble, all rights reserved.
//	Permission is granted to any person or entity except those designated
//	by the United States Department of State as a terrorist, or terrorist
//	government or agency, to use and distribute this source code provided
//	that the original copyright notice remains present and unaltered.
//==============================================================================

#ifndef drt_lib_intextstream_hpp
#define drt_lib_intextstream_hpp	102


// Identification

#ifndef NO_H_IDENT
static char	drt_lib_intextstream_hpp_REV[] =
    "@(#)drt/src/lib/intextstream.hpp $Revision: 1.2 $$Date: 2008/12/13 16:31:41 $";
#endif


// Includes

#ifndef sys_stdio_h
 #include <stdio.h>
 #define sys_stdio_h
#endif

#ifndef drt_lib_textstream_hpp
 #include "textstream.hpp"
#endif


//------------------------------------------------------------------------------
// class InTextStream
//	Controls the reading of data for an input text file.
//
//	Handles the following file encodings:
//	    8-bit (ASCII or ISO 8859-1)
//	    UTF-8
//	    UTF-16 (big-endian)
//	    UTF-16 reversed (little-endian)
//	    UTF-32 (big-endian)
//	    UTF-32 reversed (little-endian)
//	    24-bit (big-endian)			(non-standard)
//	    24-bit reversed (little-endian)	(non-standard)
//
//	Handles the following newline sequences:
//	    CR		(0D)
//	    LF		(0A)
//	    CR LF	(0D 0A)
//	    NEL		(85)
//	    Any
//	    None
//------------------------------------------------------------------------------

#define InTextStream_VS	201			// Class version

class InTextStream:
    public TextStream
{
#if TextStream_VS/100 != 2
 #error class TextStream has changed
#endif

// ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
// Static functions

private:
    static int		get_8bit(FILE *in);	// Read an 8-bit char
    static int		get_7bit(FILE *out);	// Read a 7-bit char w/ parity
    static int		get_utf8(FILE *in);	// Read a UTF-8 char
    static int		get_utf16(FILE *in);	// Read a UTF-16BE char
    static int		get_utf16r(FILE *in);	// Read a UTF-16LE char
    static int		get_utf32(FILE *in);	// Read a UTF-32BE char
    static int		get_utf32r(FILE *in);	// Read a UTF-32LE char
    static int		get_24bit(FILE *in);	// Read a 24-bit BE char
    static int		get_24bitr(FILE *in);	// Read a 24-bit LE char

// ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
// Functions

public:
    virtual /**/	~InTextStream();	// Destructor
    /**/		InTextStream();		// Constructor

    virtual bool	open(const char *fname, enum FileType ftype,
			    enum EolnType eoln);
						// Open a file stream
    virtual bool	open(FILE *fp, enum FileType ftype, enum EolnType eoln);
						// Open an I/O stream
    virtual bool	close();		// Close the stream

    int			read();			// Read a Unicode char
    int			read(int buf[], int len);
						// Read Unicode chars

private:
    /**/		InTextStream(const TextStream &o);
    const InTextStream & operator =(const InTextStream &o);

    bool		openPrep(enum FileType ftype, enum EolnType eoln);
						// Prepare to open a stream

// ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
// Variables

protected:
    int			(*m_get)(FILE *in);	// Read a char
    int			m_ungetCh;		// Push-back char
};


#endif // drt_lib_intextstream_hpp

// End intextstream.hpp