note
   description: "."
   copyright: "[
               Copyright (C) 2008-2017: Paolo Redaelli

               This library is free software; you can redistribute it and/or
               modify it under the terms of the GNU Lesser General Public License
               as published by the Free Software Foundation; either version 2.1 of
               the License, or (at your option) any later version.

               This library is distributed in the hope that it will be useful, but
               WITHOUT ANY WARRANTY; without even the implied warranty of
               MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
               Lesser General Public License for more details.

               You should have received a copy of the GNU Lesser General Public
               License along with this library; if not, write to the Free Software
               Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
               02110-1301 USA
         ]"

class XML2_NODE
   -- Minimal wrapper for xmlNode of libxml2. No effort is made to mimick
   -- SmartEiffel XML classes: their design does simply not conform.

inherit
   C_STRUCT redefine free end
   MIXED_MEMORY_HANDLING redefine free end

insert
   SHARED_XML2_NODE_CACHE
   LIBXML2_EXTERNALS

create {ANY} from_external_pointer

feature {ANY} -- Name and attributes
   name: STRING
      -- Name of the node.
      do
         create Result.from_external_copy(xml_node_get_name(handle))
      end

   attribute_at (a_name: STRING): STRING
      -- The content of the attribute named `a_name' encoded in UTF8.
      -- Void if the attribute does not exist.

      -- TODO: Result should be an heir of STRING like XML2_STRING because the
      -- string pointer shall be free with xmlFree
   require non_void_name: a_name/=Void
   local p: POINTER
   do
      p:=xml_get_prop(handle,a_name.to_external)
      if p.is_not_null then
         create Result.from_external(p)
      end
   end

   -- first_attribute: XML2_ATTRIBUTE
   --    -- The first attribute/property
   -- do
   --    not_yet_implemented
   -- end

feature {ANY} -- Nodes relationships
   parent: XML2_NODE
      -- Curren't parent, if any.
   do
      Result:=cache.wrapper_or_void(xml_node_get_parent(handle))
   end

   first: XML2_NODE
      -- First child of Current node. Can be Void
   do
      Result:=cache.wrapper_or_void(xml_node_get_children(handle))
   end

   next: XML2_NODE
      -- Next "brother" node. Can be Void
   do
      Result:=cache.wrapper_or_void(xml_node_get_next(handle))
   end

   prev: XML2_NODE
      -- Previous "brother" node. Can be Void
   do
      Result:=cache.wrapper_or_void(xml_node_get_prev(handle))
   end

   last: XML2_NODE
      -- Last child node. Can be Void
   do
      Result:=cache.wrapper_or_void(xml_node_get_last(handle))
   end

feature {} -- Implementation
   free (p: POINTER)
      do
         xml_free (p)
      end

   struct_size: INTEGER
      external "C use <libxml/tree.h>"
      alias "size_of (xmlNode)"
      end
end -- class XML2_NODE