/* $Id: rxml_input.c 528 2008-11-15 23:43:48Z cfis $ */

/* Please see the LICENSE file for copyright and distribution information */

#include <stdarg.h>
#include "ruby_libxml.h"

/*
 * Document-class: LibXML::XML::Encoding
 *
 * The encoding class exposes the encodings that libxml
 * supports via constants.  
 *
 * LibXML converts all data sources to UTF8
 * internally before processing them.  By default, 
 * LibXML determines a data source's encoding 
 * using the algorithm described on its
 * website[http://xmlsoft.org/encoding.html].  
 *
 * However, you may override a data source's encoding 
 * by using the encoding constants defined in this
 * module.
 *
 * Example 1:
 *
 *   io = File.open('some_file', 'rb')
 *   parser = XML::Parser.io(io, :encoding => XML::Encoding::ISO_8859_1)
 *   doc = parser.parse
 *
 * Example 2:
 *
 *   parser = XML::HTMLParser.file("some_file", :encoding => XML::Encoding::ISO_8859_1)
 *   doc = parser.parse
 *
 * Example 3:
 *
 *   document = XML::Document.new
 *   document.encoding = XML::Encoding::ISO_8859_1
 *   doc << XML::Node.new
 */

VALUE mXMLEncoding;


/*
 * call-seq:
 *    Input.s_to_encoding("UTF_8") -> XML::Encoding::UTF_8
 *
 * Converts an encoding string to an encoding constant
 * defined on the XML::Encoding class.
 */
static VALUE rxml_encoding_from_s(VALUE klass, VALUE encoding)
{
  xmlCharEncoding xencoding;
  
  if (encoding == Qnil)
    return Qnil;

  xencoding = xmlParseCharEncoding(StringValuePtr(encoding));
  return NUM2INT(xencoding);
}

/*
 * call-seq:
 *    Input.encoding_to_s(Input::ENCODING) -> "encoding"
 *
 * Converts an encoding contstant defined on the XML::Encoding
 * class to its text representation.
 */
static VALUE rxml_encoding_to_s(VALUE klass, VALUE encoding)
{
  const char* xecoding = xmlGetCharEncodingName(NUM2INT(encoding));

  if (!xecoding)
    return Qnil;
  else
    return rb_str_new2(xecoding);
}

void rxml_init_encoding(void)
{
  mXMLEncoding = rb_define_module_under(mXML, "Encoding");
  rb_define_module_function(mXMLEncoding, "from_s", rxml_encoding_from_s, 1);
  rb_define_module_function(mXMLEncoding, "to_s", rxml_encoding_to_s, 1);

  /* -1: No char encoding detected. */
  rb_define_const(mXMLEncoding, "ERROR", INT2NUM(XML_CHAR_ENCODING_ERROR));
  /* 0: No char encoding detected. */
  rb_define_const(mXMLEncoding, "NONE", INT2NUM(XML_CHAR_ENCODING_NONE));
  /* 1: UTF-8 */
  rb_define_const(mXMLEncoding, "UTF_8", INT2NUM(XML_CHAR_ENCODING_UTF8));
  /* 2: UTF-16 little endian. */
  rb_define_const(mXMLEncoding, "UTF_16LE", INT2NUM(XML_CHAR_ENCODING_UTF16LE));
  /* 3: UTF-16 big endian. */
  rb_define_const(mXMLEncoding, "UTF_16BE", INT2NUM(XML_CHAR_ENCODING_UTF16BE)); 
  /* 4: UCS-4 little endian. */
  rb_define_const(mXMLEncoding, "UCS_4LE", INT2NUM(XML_CHAR_ENCODING_UCS4LE));
  /* 5: UCS-4 big endian. */
  rb_define_const(mXMLEncoding, "UCS_4BE", INT2NUM(XML_CHAR_ENCODING_UCS4BE));
  /* 6: EBCDIC uh! */
  rb_define_const(mXMLEncoding, "EBCDIC", INT2NUM(XML_CHAR_ENCODING_EBCDIC)); 
  /* 7: UCS-4 unusual ordering. */
  rb_define_const(mXMLEncoding, "UCS_4_2143", INT2NUM(XML_CHAR_ENCODING_UCS4_2143));
  /* 8: UCS-4 unusual ordering. */
  rb_define_const(mXMLEncoding, "UCS_4_3412", INT2NUM(XML_CHAR_ENCODING_UCS4_3412));
  /* 9: UCS-2. */
  rb_define_const(mXMLEncoding, "UCS_2", INT2NUM(XML_CHAR_ENCODING_UCS2));
  /* 10: ISO-8859-1 ISO Latin 1. */
  rb_define_const(mXMLEncoding, "ISO_8859_1", INT2NUM(XML_CHAR_ENCODING_8859_1));
  /* 11: ISO-8859-2 ISO Latin 2. */
  rb_define_const(mXMLEncoding, "ISO_8859_2", INT2NUM(XML_CHAR_ENCODING_8859_2));
  /* 12: ISO-8859-3. */
  rb_define_const(mXMLEncoding, "ISO_8859_3", INT2NUM(XML_CHAR_ENCODING_8859_3));
  /* 13: ISO-8859-4. */
  rb_define_const(mXMLEncoding, "ISO_8859_4", INT2NUM(XML_CHAR_ENCODING_8859_4));
  /* 14: ISO-8859-5. */
  rb_define_const(mXMLEncoding, "ISO_8859_5", INT2NUM(XML_CHAR_ENCODING_8859_5));
  /* 15: ISO-8859-6. */
  rb_define_const(mXMLEncoding, "ISO_8859_6", INT2NUM(XML_CHAR_ENCODING_8859_6));
  /* 16: ISO-8859-7. */
  rb_define_const(mXMLEncoding, "ISO_8859_7", INT2NUM(XML_CHAR_ENCODING_8859_7));
  /* 17: ISO-8859-8. */
  rb_define_const(mXMLEncoding, "ISO_8859_8", INT2NUM(XML_CHAR_ENCODING_8859_8));
  /* 18: ISO-8859-9. */
  rb_define_const(mXMLEncoding, "ISO_8859_9", INT2NUM(XML_CHAR_ENCODING_8859_9));
  /* 19: ISO-2022-JP. */
  rb_define_const(mXMLEncoding, "ISO_2022_JP", INT2NUM(XML_CHAR_ENCODING_2022_JP));
  /* 20: Shift_JIS. */
  rb_define_const(mXMLEncoding, "SHIFT_JIS", INT2NUM(XML_CHAR_ENCODING_SHIFT_JIS));
  /* 21: EUC-JP. */
  rb_define_const(mXMLEncoding, "EUC_JP", INT2NUM(XML_CHAR_ENCODING_EUC_JP));
  /* 22: pure ASCII. */
  rb_define_const(mXMLEncoding, "ASCII", INT2NUM(XML_CHAR_ENCODING_ASCII));
}