/* $Id: luanode.c 1013 2008-02-14 00:09:02Z oneiros $ */

#include "luatex-api.h"
#include <ptexlib.h>
#include "nodes.h"

#undef link /* defined by cpascal.h */
#define info(a)    fixmem[(a)].hhlh
#define link(a)    fixmem[(a)].hhrh


static char *group_code_names[] = {
  "",
  "simple",
  "hbox",
  "adjusted_hbox",
  "vbox",
  "vtop",
  "align",
  "no_align",
  "output",
  "math",
  "disc",
  "insert",
  "vcenter",
  "math_choice",
  "semi_simple",
  "math_shift",
  "math_left",
  "local_box" ,
  "split_off",
  "split_keep",
  "preamble",
  "align_set",
  "fin_row"};

char *pack_type_name[] = { "exactly", "additional"};


void
lua_node_filter_s (int filterid, char *extrainfo, halfword head_node, halfword *tail_node) {
  halfword ret;  
  int a;
  lua_State *L = Luas[0];
  int callback_id = callback_defined(filterid);
  if (head_node==null || vlink(head_node)==null || callback_id==0)
    return;
  lua_rawgeti(L,LUA_REGISTRYINDEX,callback_callbacks_id);
  lua_rawgeti(L,-1, callback_id);
  if (!lua_isfunction(L,-1)) {
    lua_pop(L,2);
    return;
  }
  nodelist_to_lua(L,vlink(head_node)); /* arg 1 */
  lua_pushstring(L,extrainfo);         /* arg 2 */
  if (lua_pcall(L,2,1,0) != 0) { /* no arg, 1 result */
    fprintf(stdout,"error: %s\n",lua_tostring(L,-1));
    lua_pop(L,2);
    error();
    return;
  }
  if (lua_isboolean(L,-1)) {
    if (lua_toboolean(L,-1)!=1) {
      flush_node_list(vlink(head_node));
      vlink(head_node) = null;
    }
  } else {
    a = nodelist_from_lua(L);
    vlink(head_node)= a;
  }
  lua_pop(L,2); /* result and callback container table */
  if (fix_node_lists)
	fix_node_list(head_node);
  ret = vlink(head_node); 
  if (ret!=null) {
    while (vlink(ret)!=null)
      ret=vlink(ret); 
    *tail_node=ret;
  } else {
    *tail_node=head_node;
  }
  return ;
}

void
lua_node_filter (int filterid, int extrainfo, halfword head_node, halfword *tail_node) {
  lua_node_filter_s(filterid, group_code_names[extrainfo], head_node, tail_node);
  return ;
}



halfword
lua_hpack_filter (halfword head_node, scaled size, int pack_type, int extrainfo) {
  halfword ret;  
  lua_State *L = Luas[0];
  int callback_id = callback_defined(hpack_filter_callback);
  if (head_node==null || callback_id == 0)
    return head_node;
  lua_rawgeti(L,LUA_REGISTRYINDEX,callback_callbacks_id);
  lua_rawgeti(L,-1, callback_id);
  if (!lua_isfunction(L,-1)) {
    lua_pop(L,2);
    return head_node;
  }

  nodelist_to_lua(L,head_node);
  lua_pushstring(L,group_code_names[extrainfo]);
  lua_pushnumber(L,size);
  lua_pushstring(L,pack_type_name[pack_type]);
  if (lua_pcall(L,4,1,0) != 0) { /* no arg, 1 result */
    fprintf(stdout,"error: %s\n",lua_tostring(L,-1));
    lua_pop(L,2);
    error();
    return head_node;
  }
  ret = head_node;
  if (lua_isboolean(L,-1)) {
    if (lua_toboolean(L,-1)!=1) {
      flush_node_list(head_node);
      ret = null;
    }
  } else {
    ret = nodelist_from_lua(L);
  }
  lua_pop(L,2); /* result and callback container table */
  /*  lua_gc(L,LUA_GCSTEP, LUA_GC_STEP_SIZE);*/
  if (fix_node_lists)
	fix_node_list(ret);
  return ret;
}

halfword
lua_vpack_filter (halfword head_node, scaled size, int pack_type, scaled maxd, int extrainfo) {
  halfword ret;  
  integer callback_id ; 
  lua_State *L = Luas[0];
  if (head_node==null)
	return head_node;
  if (strcmp("output",group_code_names[extrainfo])==0) {
    callback_id = callback_defined(pre_output_filter_callback);
  } else {
    callback_id = callback_defined(vpack_filter_callback);
  }
  if (callback_id==0) {
    return head_node;
  }
  lua_rawgeti(L,LUA_REGISTRYINDEX,callback_callbacks_id);
  lua_rawgeti(L,-1, callback_id);
  if (!lua_isfunction(L,-1)) {
    lua_pop(L,2);
    return head_node;
  }
  nodelist_to_lua(L,head_node);
  lua_pushstring(L,group_code_names[extrainfo]);
  lua_pushnumber(L,size);
  lua_pushstring(L,pack_type_name[pack_type]);
  lua_pushnumber(L,maxd);
  if (lua_pcall(L,5,1,0) != 0) { /* no arg, 1 result */
    fprintf(stdout,"error: %s\n",lua_tostring(L,-1));
    lua_pop(L,2);
    error();
    return head_node;
  }
  ret = head_node;
  if (lua_isboolean(L,-1)) {
    if (lua_toboolean(L,-1)!=1) {
      flush_node_list(head_node);
      ret = null;
    }
  } else {
    ret = nodelist_from_lua(L);
  }
  lua_pop(L,2); /* result and callback container table */
  /*  lua_gc(L,LUA_GCSTEP, LUA_GC_STEP_SIZE);*/
  if (fix_node_lists)
	fix_node_list(ret);
  return ret;
}


/* This is a quick hack to fix etex's \lastnodetype now that
 * there are many more visible node types. TODO: check the
 * eTeX manual for the expected return values.
 */

int 
visible_last_node_type (int n) {
  int i = type(n);
  if ((i!=math_node) && (i<=unset_node))  
    return i+1;
  if (i==glyph_node)
    return -1; 
  if (i==whatsit_node && subtype(n)==local_par_node)
    return -1;  
  if (i==255)
    return -1 ; /* this is not right, probably dir nodes! */
  return last_known_node +1 ;
}