/*
 * Document-class: FastXml::AttrList
 *
 * call-seq:
 *  doc = FastXml( docfile ) # from FastXml::Doc
 *  n = doc.root             # pull the root node 
 *  attrlist = n.attr        # pull the FastXml::AttrList for the node
 *  puts attrlist[:some_attr]
 *  puts attrlist["some_attr"]
 */
// Please see the LICENSE file for copyright, licensing and distribution information
 
#include "fastxml.h"
#include "fastxml_node.h"
#include "fastxml_doc.h"
#include "fastxml_nodelist.h"
#include "fastxml_attrlist.h"
 
/* {{{ fastml_attr_list
*/
void Init_fastxml_attrlist()
{
  #ifdef RDOC_SHOULD_BE_SMARTER__THIS_IS_NEVER_RUN
    rb_mFastXml = rb_define_module( "FastXml" );
  #endif
  rb_cFastXmlAttrList = rb_define_class_under( rb_mFastXml, "AttrList", rb_cObject );    
    
  rb_include_module( rb_cFastXmlAttrList, rb_mEnumerable );
  rb_define_method( rb_cFastXmlAttrList, "initialize", fastxml_attrlist_initialize, 0 );
  rb_define_method( rb_cFastXmlAttrList, "[]", fastxml_attrlist_indexer, 1 );
  rb_define_method( rb_cFastXmlAttrList, "[]=", fastxml_attrlist_indexer_set, 2 );
  rb_define_method( rb_cFastXmlAttrList, "include?", fastxml_attrlist_include, 1 );  
}
 
VALUE fastxml_attrlist_initialize(VALUE self)
{
    return self;
}
 
/* Returns the value of the attribute with the provided attr_name
 * as a string.
 * nil if the attribute does not exist.
 *
 * call-seq:
 *   puts node.attr[:an_attr_name]
 */
VALUE fastxml_attrlist_indexer(VALUE self, VALUE attr_name)
{
  VALUE ret, dv, attr_raw_str;
  fxml_data_t *data;
  xmlChar *raw_ret, *name_str;
  
  if (attr_name == Qnil)
    return Qnil;  
  
  dv = rb_iv_get( self, "@lxml_doc" );
  Data_Get_Struct( dv, fxml_data_t, data );
  
  attr_raw_str = rb_funcall( attr_name, s_to_s, 0 );
  name_str = (xmlChar*)StringValuePtr( attr_raw_str );
  raw_ret = xmlGetProp( data->node, name_str );
  if (raw_ret == NULL)
    return Qnil;
    
  ret = rb_str_new2( (const char*)raw_ret );
  xmlFree( raw_ret );
  
  return ret;
}
 
/* Assignes a value to the attribute with the provided attr_name.
 * if the value provided is nil, the attribute is removed from the element.
 * 
 * call-seq:
 *  node.attr[:an_attr_name] = "testing" # adds the attribute if it doesn't exist
 *  node.attr[:an_attr_name] = nil       # removes the attribute if it exists
 */
VALUE fastxml_attrlist_indexer_set(VALUE self, VALUE attr_name, VALUE attr_value)
{
  VALUE dv, attr_raw_str;
  fxml_data_t *data;
  xmlChar *val, *name_str;
  
  if (attr_name == Qnil)
    return Qnil;  
  
  dv = rb_iv_get( self, "@lxml_doc" );
  Data_Get_Struct( dv, fxml_data_t, data );
  
  attr_raw_str = rb_funcall( attr_name, s_to_s, 0 );
  name_str = (xmlChar*)StringValuePtr( attr_raw_str );
 
  if (attr_value == Qnil) {
    xmlUnsetProp( data->node, name_str ); // don't care if the node doesn't exist, as the end result is the same.
  } else {
    val = (xmlChar*)StringValuePtr( attr_value );
 
      xmlSetProp( data->node, name_str, val );
  }
 
 
  return attr_value;
}
 
/* Returns True if the FastXml::AttrList contains an attribute
 * with the specified attr_name. Returns nil otherwise.
 *
 * call-seq:
 *  puts "FAIL" unless node.attr.include?(:a_required_node)
 */
VALUE fastxml_attrlist_include(VALUE self, VALUE attr_name)
{
  VALUE dv, attr_raw_str;
  fxml_data_t *data;
  xmlChar *raw_ret, *name_str;
  
  if (attr_name == Qnil)
    return Qnil;
  
  dv = rb_iv_get( self, "@lxml_doc" );
  Data_Get_Struct( dv, fxml_data_t, data );
  
  attr_raw_str = rb_funcall( attr_name, s_to_s, 0 );
  name_str = (xmlChar*)StringValuePtr( attr_raw_str );
  raw_ret = xmlGetProp( data->node, name_str );
  if (raw_ret == NULL)
    return Qnil;  
  
  return Qtrue;
}
 
 
/* }}} fastxml_attr_list
*/