/* insertion.c -- insertions for Texinfo.
   $Id: insertion.c,v 1.21 2003/04/01 14:34:18 karl Exp $

   Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003 Free Software
   Foundation, Inc.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2, or (at your option)
   any later version.

   This program 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 General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software Foundation,
   Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */

#include "system.h"
#include "cmds.h"
#include "defun.h"
#include "insertion.h"
#include "macro.h"
#include "makeinfo.h"
#include "xml.h"

/* Must match list in insertion.h.  */
static char *insertion_type_names[] =
{ 
  "cartouche", "copying", "defcv", "deffn", "defivar", "defmac",
  "defmethod", "defop", "defopt", "defspec", "deftp", "deftypefn",
  "deftypefun", "deftypeivar", "deftypemethod", "deftypeop",
  "deftypevar", "deftypevr", "defun", "defvar", "defvr", "detailmenu",
  "direntry", "display", "documentdescription", "enumerate", "example",
  "flushleft", "flushright", "format", "ftable", "group", "ifclear",
  "ifhtml", "ifinfo", "ifnothtml", "ifnotinfo", "ifnotplaintext", "ifnottex", "ifnotxml",
  "ifplaintext", "ifset", "iftex", "ifxml", "itemize", "lisp", "menu",
  "multitable", "quotation", "rawhtml", "rawtex", "smalldisplay",
  "smallexample", "smallformat", "smalllisp", "verbatim", "table",
  "tex", "vtable", "bad_type"
};

/* All nested environments.  */
INSERTION_ELT *insertion_stack = NULL;

/* How deeply we're nested.  */
int insertion_level = 0;

/* Set to 1 if we've processed (commentary) text in a @menu that
   wasn't part of a menu item.  */
int had_menu_commentary;

/* How to examine menu lines.  */
int in_detailmenu = 0;

/* Whether to examine menu lines.  */
int in_menu = 0;

/* Set to 1 if <p> is written in normal context. 
   Used for menu and itemize. */
int in_paragraph = 0;

static const char dl_tag[] = "<dl>\n";
extern void cm_insert_copying ();


void
init_insertion_stack ()
{
  insertion_stack = NULL;
}

/* Return the type of the current insertion. */
static enum insertion_type
current_insertion_type ()
{
  return insertion_level ? insertion_stack->insertion : bad_type;
}

/* Return the string which is the function to wrap around items, or NULL
   if we're not in an environment where @item is ok.  */
static char *
current_item_function ()
{
  int done = 0;
  INSERTION_ELT *elt = insertion_stack;

  /* Skip down through the stack until we find an insertion with an
     itemize function defined, i.e., skip conditionals, @cartouche, etc.  */
  while (!done && elt)
    {
      switch (elt->insertion)
        {
        /* This list should match the one in cm_item.  */
        case ifclear:
        case ifhtml:
        case ifinfo:
        case ifnothtml:
        case ifnotinfo:
        case ifnotplaintext:
        case ifnottex:
	case ifnotxml:
        case ifplaintext:
        case ifset:
        case iftex:
	case ifxml:
        case rawhtml:
        case rawtex:
        case tex:
        case cartouche:
          elt = elt->next;
          break;
      
        default:
          done = 1;
        }
    }

  /* item_function usually gets assigned the empty string.  */
  return done && (*elt->item_function) ? elt->item_function : NULL;
}

/* Parse the item marker function off the input.  If result is just "@",
   change it to "@ ", since "@" by itself is not a command.  This makes
   "@ ", "@\t", and "@\n" all the same, but their default meanings are
   the same anyway, and let's not worry about supporting redefining them.  */
char *
get_item_function ()
{
  char *item_function;
  char *item_loc;
  
  get_rest_of_line (0, &item_function);

  /* If the document erroneously says
       @itemize @bullet @item foobar
     it's nicer to give an error up front than repeat `@bullet expected
     braces' until we get a segmentation fault.  */
  item_loc = strstr (item_function, "@item");
  if (item_loc)
    {
      line_error (_("@item not allowed in argument to @itemize"));
      *item_loc = 0;
    }

  /* If we hit the end of text in get_rest_of_line, backing up
     input pointer will cause the last character of the last line
     be pushed back onto the input, which is wrong.  */
  if (input_text_offset < input_text_length)
    backup_input_pointer ();

  if (STREQ (item_function, "@"))
    {
      free (item_function);
      item_function = xstrdup ("@ ");
    }

  return item_function;
}

 /* Push the state of the current insertion on the stack. */
void
push_insertion (type, item_function)
     enum insertion_type type;
     char *item_function;
{
  INSERTION_ELT *new = xmalloc (sizeof (INSERTION_ELT));

  new->item_function = item_function;
  new->filling_enabled = filling_enabled;
  new->indented_fill = indented_fill;
  new->insertion = type;
  new->line_number = line_number;
  new->filename = xstrdup (input_filename);
  new->inhibited = inhibit_paragraph_indentation;
  new->in_fixed_width_font = in_fixed_width_font;
  new->next = insertion_stack;
  insertion_stack = new;
  insertion_level++;
}

 /* Pop the value on top of the insertion stack into the
    global variables. */
void
pop_insertion ()
{
  INSERTION_ELT *temp = insertion_stack;

  if (temp == NULL)
    return;

  in_fixed_width_font = temp->in_fixed_width_font;
  inhibit_paragraph_indentation = temp->inhibited;
  filling_enabled = temp->filling_enabled;
  indented_fill = temp->indented_fill;
  free_and_clear (&(temp->item_function));
  free_and_clear (&(temp->filename));
  insertion_stack = insertion_stack->next;
  free (temp);
  insertion_level--;
}

 /* Return a pointer to the print name of this
    enumerated type. */
const char *
insertion_type_pname (type)
     enum insertion_type type;
{
  if ((int) type < (int) bad_type)
    return insertion_type_names[(int) type];
  else
    return _("Broken-Type in insertion_type_pname");
}

/* Return the insertion_type associated with NAME.
   If the type is not one of the known ones, return BAD_TYPE. */
enum insertion_type
find_type_from_name (name)
     char *name;
{
  int index = 0;
  while (index < (int) bad_type)
    {
      if (STREQ (name, insertion_type_names[index]))
        return (enum insertion_type) index;
      if (index == rawhtml && STREQ (name, "html"))
        return rawhtml;
      if (index == rawhtml && STREQ (name, "xml"))
        return rawhtml;
      if (index == rawtex && STREQ (name, "tex"))
        return rawtex;
      index++;
    }
  return bad_type;
}

int
defun_insertion (type)
     enum insertion_type type;
{
  return 0
     || (type == defcv)
     || (type == deffn)
     || (type == defivar)
     || (type == defmac)
     || (type == defmethod)
     || (type == defop)
     || (type == defopt)
     || (type == defspec)
     || (type == deftp)
     || (type == deftypefn)
     || (type == deftypefun)
     || (type == deftypeivar)
     || (type == deftypemethod)
     || (type == deftypeop)
     || (type == deftypevar)
     || (type == deftypevr)
     || (type == defun)
     || (type == defvar)
     || (type == defvr)
  ;
}

/* MAX_NS is the maximum nesting level for enumerations.  I picked 100
   which seemed reasonable.  This doesn't control the number of items,
   just the number of nested lists. */
#define max_stack_depth 100
#define ENUM_DIGITS 1
#define ENUM_ALPHA  2
typedef struct {
  int enumtype;
  int enumval;
} DIGIT_ALPHA;

DIGIT_ALPHA enumstack[max_stack_depth];
int enumstack_offset = 0;
int current_enumval = 1;
int current_enumtype = ENUM_DIGITS;
char *enumeration_arg = NULL;

void
start_enumerating (at, type)
     int at, type;
{
  if ((enumstack_offset + 1) == max_stack_depth)
    {
      line_error (_("Enumeration stack overflow"));
      return;
    }
  enumstack[enumstack_offset].enumtype = current_enumtype;
  enumstack[enumstack_offset].enumval = current_enumval;
  enumstack_offset++;
  current_enumval = at;
  current_enumtype = type;
}

void
stop_enumerating ()
{
  --enumstack_offset;
  if (enumstack_offset < 0)
    enumstack_offset = 0;

  current_enumval = enumstack[enumstack_offset].enumval;
  current_enumtype = enumstack[enumstack_offset].enumtype;
}

/* Place a letter or digits into the output stream. */
void
enumerate_item ()
{
  char temp[10];

  if (current_enumtype == ENUM_ALPHA)
    {
      if (current_enumval == ('z' + 1) || current_enumval == ('Z' + 1))
        {
          current_enumval = ((current_enumval - 1) == 'z' ? 'a' : 'A');
          warning (_("lettering overflow, restarting at %c"), current_enumval);
        }
      sprintf (temp, "%c. ", current_enumval);
    }
  else
    sprintf (temp, "%d. ", current_enumval);

  indent (output_column += (current_indent - strlen (temp)));
  add_word (temp);
  current_enumval++;
}

static void
enum_html ()
{
  char type;
  int start;

  if (isdigit (*enumeration_arg))
    {
      type = '1';
      start = atoi (enumeration_arg);
    }
  else if (isupper (*enumeration_arg))
    {
      type = 'A';
      start = *enumeration_arg - 'A' + 1;
    }
  else
    {
      type = 'a';
      start = *enumeration_arg - 'a' + 1;
    }

  add_word_args ("<ol type=%c start=%d>\n", type, start);
}

/* Conditionally parse based on the current command name. */
void
command_name_condition ()
{
  char *discarder = xmalloc (8 + strlen (command));

  sprintf (discarder, "\n%cend %s", COMMAND_PREFIX, command);
  discard_until (discarder);
  discard_until ("\n");

  free (discarder);
}

/* This is where the work for all the "insertion" style
   commands is done.  A huge switch statement handles the
   various setups, and generic code is on both sides. */
void
begin_insertion (type)
     enum insertion_type type;
{
  int no_discard = 0;

  if (defun_insertion (type))
    {
      push_insertion (type, xstrdup (""));
      no_discard++;
    }
  else
    {
      push_insertion (type, get_item_function ());
    }

  switch (type)
    {
    case menu:
      if (!no_headers)
        close_paragraph ();

      filling_enabled = no_indent = 0;
      inhibit_paragraph_indentation = 1;

      if (html)
        {
          had_menu_commentary = 1;
        }
      else if (!no_headers && !xml)
        add_word ("* Menu:\n");

      if (xml)
        xml_insert_element (MENU, START);

      next_menu_item_number = 1;
      in_menu++;
      in_fixed_width_font++;
      no_discard++;
      break;

    case detailmenu:
      if (!in_menu)
        {
          if (!no_headers)
            close_paragraph ();

          filling_enabled = no_indent = 0;
          inhibit_paragraph_indentation = 1;

          no_discard++;
        }

      in_fixed_width_font++;
      in_detailmenu++;
      break;

    case direntry:
      close_single_paragraph ();
      filling_enabled = no_indent = 0;
      inhibit_paragraph_indentation = 1;
      insert_string ("START-INFO-DIR-ENTRY\n");
      break;

    case documentdescription:
      {
        char *desc;
        int start_of_end;
        int save_fixed_width;

        discard_until ("\n"); /* ignore the @documentdescription line */
        start_of_end = get_until ("\n@end documentdescription", &desc);
        save_fixed_width = in_fixed_width_font;

        in_fixed_width_font = 0;
        document_description = expansion (desc, 0);
        free (desc);

        in_fixed_width_font = save_fixed_width;
        input_text_offset = start_of_end; /* go back to the @end to match */
      }
      break;

    case copying:
      {
        /* Save the copying text away for @insertcopying,
           typically used on the back of the @titlepage (for TeX) and
           the Top node (for info/html).  */
        char *text;
        int start_of_end;
	int save_paragraph_indentation;

        discard_until ("\n"); /* ignore remainder of @copying line */
        start_of_end = get_until ("\n@end copying", &text);

        /* include all the output-format-specific markup.  */
	if (docbook)
	  {
	    save_paragraph_indentation = inhibit_paragraph_indentation;
	    inhibit_paragraph_indentation = 1;
	  }
        copying_text = full_expansion (text, 0);
        free (text);

	if (docbook)
	  inhibit_paragraph_indentation = save_paragraph_indentation;
	
        input_text_offset = start_of_end; /* go back to the @end to match */
      }
      
      /* For info, output the copying text right away, so it will end up
         in the header of the Info file, before the first node, and thus
         get copied automatically to all the split files.  For xml, also
         output it right away since xml output is never split.
         For html, we output it specifically in html_output_head. 
         For plain text, there's no way to hide it, so the author must
          use @insertcopying in the desired location.  */
      if (docbook)
	{
	  if (!xml_in_bookinfo)
	    {
	      xml_insert_element (BOOKINFO, START);
	      xml_in_bookinfo = 1;
	    }
	  if (!xml_in_abstract)
	    {
	      xml_insert_element (ABSTRACT, START);
	      xml_in_abstract = 1;
	    }
	}
      if (!html && !no_headers)
        cm_insert_copying ();
      if (docbook && xml_in_abstract)
	{
	  xml_insert_element (ABSTRACT, END);
	  xml_in_abstract = 0;
	}
      break;
      
    case quotation:
      /* @quotation does filling (@display doesn't).  */
      if (html)
        add_word ("<blockquote>\n");
      else
        {
          /* with close_single_paragraph, we get no blank line above
             within @copying.  */
          close_paragraph ();
          last_char_was_newline = no_indent = 0;
          indented_fill = filling_enabled = 1;
          inhibit_paragraph_indentation = 1;
        }
      current_indent += default_indentation_increment;
      break;

    case display:
    case smalldisplay:
    case example:
    case smallexample:
    case lisp:
    case smalllisp:
      /* Like @display but without indentation. */
    case smallformat:
    case format:
      close_single_paragraph ();
      inhibit_paragraph_indentation = 1;
      in_fixed_width_font++;
      filling_enabled = 0;
      last_char_was_newline = 0;

      if (html)
        /* Kludge alert: if <pre> is followed by a newline, IE3
           renders an extra blank line before the pre-formatted block.
           Other browsers seem to not mind one way or the other.  */
        add_word_args ("<pre class=\"%s\">", command);

      if (type != format && type != smallformat)
        {
          current_indent += default_indentation_increment;
          if (html)
            {
              /* Since we didn't put \n after <pre>, we need to insert
                 the indentation by hand.  */
              int i;
              for (i = current_indent; i > 0; i--)
                add_char (' ');
            }
        }

      break;

    case multitable:
      do_multitable ();
      break;

    case table:
    case ftable:
    case vtable:
    case itemize:
      close_single_paragraph ();
      current_indent += default_indentation_increment;
      filling_enabled = indented_fill = 1;
#if defined (INDENT_PARAGRAPHS_IN_TABLE)
      inhibit_paragraph_indentation = 0;
#else
      inhibit_paragraph_indentation = 1;
#endif /* !INDENT_PARAGRAPHS_IN_TABLE */

      /* Make things work for losers who forget the itemize syntax. */
      if (type == itemize)
        {
          if (!(*insertion_stack->item_function))
            {
              free (insertion_stack->item_function);
              insertion_stack->item_function = xstrdup ("@bullet");
            }
        }

      if (!*insertion_stack->item_function)
        {
          line_error (_("%s requires an argument: the formatter for %citem"),
                      insertion_type_pname (type), COMMAND_PREFIX);
        }

      if (html)
        {
          if (type == itemize)
            {
              add_word ("<ul>\n");
              in_paragraph = 0;
            }
          else
            add_word (dl_tag);
        }
      if (xml)
        xml_begin_table (type, insertion_stack->item_function);
      break;

    case enumerate:
      close_single_paragraph ();
      no_indent = 0;
#if defined (INDENT_PARAGRAPHS_IN_TABLE)
      inhibit_paragraph_indentation = 0;
#else
      inhibit_paragraph_indentation = 1;
#endif /* !INDENT_PARAGRAPHS_IN_TABLE */

      current_indent += default_indentation_increment;
      filling_enabled = indented_fill = 1;

      if (html)
        {
          enum_html ();
          in_paragraph = 0;
        }

      if (xml)
        xml_begin_enumerate (enumeration_arg);
      
      if (isdigit (*enumeration_arg))
        start_enumerating (atoi (enumeration_arg), ENUM_DIGITS);
      else
        start_enumerating (*enumeration_arg, ENUM_ALPHA);
      break;

      /* @group does nothing special in makeinfo. */
    case group:
      /* Only close the paragraph if we are not inside of an
         @example-like environment. */
      if (xml)
        xml_insert_element (GROUP, START);
      else if (!insertion_stack->next
          || (insertion_stack->next->insertion != display
              && insertion_stack->next->insertion != smalldisplay
              && insertion_stack->next->insertion != example
              && insertion_stack->next->insertion != smallexample
              && insertion_stack->next->insertion != lisp
              && insertion_stack->next->insertion != smalllisp
              && insertion_stack->next->insertion != format
              && insertion_stack->next->insertion != smallformat
              && insertion_stack->next->insertion != flushleft
              && insertion_stack->next->insertion != flushright))
        close_single_paragraph ();
      break;

    case cartouche:
      if (html)
	add_word ("<table class=\"cartouche\" border=1><tr><td>\n");
      if (in_menu)
        no_discard++;
      break;

      /* Insertions that are no-ops in info, but do something in TeX. */
    case ifclear:
    case ifhtml:
    case ifinfo:
    case ifnothtml:
    case ifnotinfo:
    case ifnotplaintext:
    case ifnottex:
    case ifnotxml:
    case ifplaintext:
    case ifset:
    case iftex:
    case ifxml:
    case rawtex:
      if (in_menu)
        no_discard++;
      break;

    case rawhtml:
      escape_html = 0;
      break;

    case defcv:
    case deffn:
    case defivar:
    case defmac:
    case defmethod:
    case defop:
    case defopt:
    case defspec:
    case deftp:
    case deftypefn:
    case deftypefun:
    case deftypeivar:
    case deftypemethod:
    case deftypeop:
    case deftypevar:
    case deftypevr:
    case defun:
    case defvar:
    case defvr:
      inhibit_paragraph_indentation = 1;
      filling_enabled = indented_fill = 1;
      current_indent += default_indentation_increment;
      no_indent = 0;
      break;

    case flushleft:
      close_single_paragraph ();
      inhibit_paragraph_indentation = 1;
      filling_enabled = indented_fill = no_indent = 0;
      if (html)
        add_word ("<div align=\"left\">");
      break;

    case flushright:
      close_single_paragraph ();
      filling_enabled = indented_fill = no_indent = 0;
      inhibit_paragraph_indentation = 1;
      force_flush_right++;
      if (html)
        add_word ("<div align=\"right\">");
      break;

    default:
      line_error ("begin_insertion internal error: type=%d", type);

    }

  if (!no_discard)
    discard_until ("\n");
}

/* Try to end the insertion with the specified TYPE.  With a value of
   `bad_type', TYPE gets translated to match the value currently on top
   of the stack.  Otherwise, if TYPE doesn't match the top of the
   insertion stack, give error. */
void
end_insertion (type)
     enum insertion_type type;
{
  enum insertion_type temp_type;

  if (!insertion_level)
    return;

  temp_type = current_insertion_type ();

  if (type == bad_type)
    type = temp_type;

  if (type != temp_type)
    {
      line_error
        (_("`@end' expected `%s', but saw `%s'"),
         insertion_type_pname (temp_type), insertion_type_pname (type));
      return;
    }

  pop_insertion ();

  if (xml)
    {
      switch (type)
        {
        case ifinfo:
        case documentdescription:       
          break;
        case copying:
          xml_insert_element (COPYING, END);
          break;
        case quotation:
          xml_insert_element (QUOTATION, END);
          break;
        case example:
          xml_insert_element (EXAMPLE, END);
          break;
        case smallexample:
          xml_insert_element (SMALLEXAMPLE, END);
          break;
        case lisp:
          xml_insert_element (LISP, END);
          break;
        case smalllisp:
          xml_insert_element (SMALLLISP, END);
          break;
        case cartouche:
          xml_insert_element (CARTOUCHE, END);
          break;
        case format:
	  if (docbook && xml_in_bookinfo && xml_in_abstract)
	    {
	      xml_insert_element (ABSTRACT, END);
	      xml_in_abstract = 0;
	    }
	  else
	    xml_insert_element (FORMAT, END);
          break;
        case smallformat:
          xml_insert_element (SMALLFORMAT, END);
          break;
        case display:
          xml_insert_element (DISPLAY, END);
          break;
        case smalldisplay:
          xml_insert_element (SMALLDISPLAY, END);
          break;
        case table:
        case ftable:
        case vtable:      
        case itemize:
          xml_end_table (type);
          break;
        case enumerate:
          xml_end_enumerate (type);
          break;
        case group:
          xml_insert_element (GROUP, END);
          break;
        }
    }
  switch (type)
    {
      /* Insertions which have no effect on paragraph formatting. */
    case copying:
    case documentdescription:
    case ifclear:
    case ifinfo:
    case ifhtml:
    case ifnothtml:
    case ifnotinfo:
    case ifnotplaintext:
    case ifnottex:
    case ifnotxml:
    case ifplaintext:
    case ifset:
    case iftex:
    case ifxml:
    case rawtex:
      break;

    case rawhtml:
      escape_html = 1;
      break;

    case detailmenu:
      in_detailmenu--;          /* No longer hacking menus. */
      if (!in_menu)
        {
          if (!no_headers)
            close_insertion_paragraph ();
        }
      break;

    case direntry:              /* Eaten if html. */
      insert_string ("END-INFO-DIR-ENTRY\n\n");
      close_insertion_paragraph ();
      break;

    case menu:
      in_menu--;                /* No longer hacking menus. */
      if (html && !no_headers)
        add_word ("</ul>\n");
      else if (!no_headers)
        close_insertion_paragraph ();
      break;

    case multitable:
      end_multitable ();
      break;

    case enumerate:
      stop_enumerating ();
      close_insertion_paragraph ();
      current_indent -= default_indentation_increment;
      if (html)
        add_word ("</ol>\n");
      break;

    case flushleft:
      if (html)
        add_word ("</div>\n");
      close_insertion_paragraph ();
      break;

    case cartouche:
      if (html)
	add_word ("</td></tr></table>\n");
      close_insertion_paragraph ();
      break;

    case group:
      close_insertion_paragraph ();
      break;

    case format:
    case smallformat:
    case display:
    case smalldisplay:
    case example:
    case smallexample:
    case lisp:
    case smalllisp:
    case quotation:
      /* @format and @smallformat are the only fixed_width insertion
         without a change in indentation. */
      if (type != format && type != smallformat)
        current_indent -= default_indentation_increment;

      if (html)
        add_word (type == quotation ? "</blockquote>\n" : "</pre>\n");

      /* The ending of one of these insertions always marks the
         start of a new paragraph. */
      close_insertion_paragraph ();
      break;

    case table:
    case ftable:
    case vtable:
      current_indent -= default_indentation_increment;
      if (html)
        add_word ("</dl>\n");
      close_insertion_paragraph ();
      break;

    case itemize:
      current_indent -= default_indentation_increment;
      if (html)
        add_word ("</ul>\n");
      close_insertion_paragraph ();
      break;

    case flushright:
      force_flush_right--;
      if (html)
        add_word ("</div>\n");
      close_insertion_paragraph ();
      break;

    /* Handle the @defun insertions with this default clause. */
    default:
      {
        enum insertion_type base_type;

        if (type < defcv || type > defvr)
          line_error ("end_insertion internal error: type=%d", type);
  
        base_type = get_base_type (type);
        switch (base_type)
          {
          case deffn:
          case defvr:
          case deftp:
          case deftypefn:
          case deftypevr:
          case defcv:
          case defop:
          case deftypemethod:
          case deftypeop:
          case deftypeivar:
            if (html)
              /* close the tables which has been opened in defun.c */
              add_word ("</td></tr>\n</table>\n");
            break;
          } /* switch (base_type)... */
  
        current_indent -= default_indentation_increment;
        close_insertion_paragraph ();
      }
      break;
      
    }

  if (current_indent < 0)
    line_error ("end_insertion internal error: current indent=%d",
                current_indent);
}

/* Insertions cannot cross certain boundaries, such as node beginnings.  In
   code that creates such boundaries, you should call `discard_insertions'
   before doing anything else.  It prints the errors for you, and cleans up
   the insertion stack.

   With nonzero SPECIALS_OK argument, allows unmatched
   @if... conditionals, otherwise not.  This is because conditionals can
   cross node boundaries.  Always happens with the @top node, for example.  */
void
discard_insertions (specials_ok)
    int specials_ok;
{
  int real_line_number = line_number;
  while (insertion_stack)
    {
      if (specials_ok
          && ((ifclear <= insertion_stack->insertion
               && insertion_stack->insertion <= iftex)
              || insertion_stack->insertion == rawhtml
              || insertion_stack->insertion == rawtex))
        break;
      else
        {
          const char *offender = insertion_type_pname (insertion_stack->insertion);

          file_line_error (insertion_stack->filename,
                           insertion_stack->line_number,
                           _("No matching `%cend %s'"), COMMAND_PREFIX,
                           offender);
          pop_insertion ();
        }
    }
  line_number = real_line_number;
}

/* Insertion (environment) commands.  */

void
cm_quotation ()
{
  if (xml)
    xml_insert_element (QUOTATION, START);
  begin_insertion (quotation);
}

void
cm_example ()
{
  if (xml)
    xml_insert_element (EXAMPLE, START);
  begin_insertion (example);
}

void
cm_smallexample ()
{
  if (xml)
    xml_insert_element (SMALLEXAMPLE, START);
  begin_insertion (smallexample);
}

void
cm_lisp ()
{
  if (xml)
    xml_insert_element (LISP, START);
  begin_insertion (lisp);
}

void
cm_smalllisp ()
{
  if (xml)
    xml_insert_element (SMALLLISP, START);
  begin_insertion (smalllisp);
}

void
cm_cartouche ()
{
  if (xml)
    xml_insert_element (CARTOUCHE, START);
  begin_insertion (cartouche);
}

void
cm_copying ()
{
  if (xml)
    xml_insert_element (COPYING, START);
  begin_insertion (copying);
}

/* Not an insertion, despite the name, but it goes with cm_copying.  */
void
cm_insert_copying ()
{
  if (copying_text)
    { /* insert_string rather than add_word because we've already done
         full expansion on copying_text when we saved it.  */
      insert_string (copying_text);
      insert ('\n');
      
      /* Update output_position so that the node positions in the tag
         tables will take account of the copying text.  */
      flush_output ();
    }
}

void
cm_format ()
{
  if (xml)
    {
      if (docbook && xml_in_bookinfo)
	{
	  xml_insert_element (ABSTRACT, START);
	  xml_in_abstract = 1;
	}
      else
	xml_insert_element (FORMAT, START);
    }
  begin_insertion (format);
}

void
cm_smallformat ()
{
  if (xml)
    xml_insert_element (SMALLFORMAT, START);
  begin_insertion (smallformat);
}

void
cm_display ()
{
  if (xml)
    xml_insert_element (DISPLAY, START);
  begin_insertion (display);
}

void
cm_smalldisplay ()
{
  if (xml)
    xml_insert_element (SMALLDISPLAY, START);
  begin_insertion (smalldisplay);
}

void
cm_direntry ()
{
  if (html || xml)
    command_name_condition ();
  else
    begin_insertion (direntry);
}

void
cm_documentdescription ()
{
  if (html || xml)
    begin_insertion (documentdescription);
  else
    command_name_condition ();
}


void
cm_itemize ()
{
  begin_insertion (itemize);
}

/* Start an enumeration insertion of type TYPE.  If the user supplied
   no argument on the line, then use DEFAULT_STRING as the initial string. */
static void
do_enumeration (type, default_string)
     int type;
     char *default_string;
{
  get_until_in_line (0, ".", &enumeration_arg);
  canon_white (enumeration_arg);

  if (!*enumeration_arg)
    {
      free (enumeration_arg);
      enumeration_arg = xstrdup (default_string);
    }

  if (!isdigit (*enumeration_arg) && !isletter (*enumeration_arg))
    {
      warning (_("%s requires letter or digit"), insertion_type_pname (type));

      switch (type)
        {
        case enumerate:
          default_string = "1";
          break;
        }
      enumeration_arg = xstrdup (default_string);
    }
  begin_insertion (type);
}

void
cm_enumerate ()
{
  do_enumeration (enumerate, "1");
}

/*  Handle verbatim environment:
    find_end_verbatim == 0:  process until end of file
    find_end_verbatim != 0:  process until 'COMMAND_PREFIXend verbatim'
                             or end of file

  We cannot simply copy input stream onto output stream; as the
  verbatim environment may be encapsulated in an @example environment,
  for example. */
void
handle_verbatim_environment (find_end_verbatim)
  int find_end_verbatim;
{
  int character;
  int seen_end = 0;
  int save_filling_enabled = filling_enabled;
  int save_inhibit_paragraph_indentation = inhibit_paragraph_indentation;

  close_single_paragraph ();
  inhibit_paragraph_indentation = 1;
  filling_enabled = 0;
  in_fixed_width_font++;
  last_char_was_newline = 0;

  /* No indentation: this is verbatim after all
     If you want indent, enclose @verbatim in @example
       current_indent += default_indentation_increment;
   */

  if (html)
    add_word ("<pre class=\"verbatim\">");

  while (input_text_offset < input_text_length)
    {
      character = curchar ();

      if (character == '\n')
        line_number++;
      /*
        Assume no newlines in END_VERBATIM
      */
      else if (find_end_verbatim && (character == COMMAND_PREFIX) /* @ */
          && (input_text_length - input_text_offset > sizeof (END_VERBATIM))
          && !strncmp (&input_text[input_text_offset+1], END_VERBATIM,
                       sizeof (END_VERBATIM)-1))
        {
          input_text_offset += sizeof (END_VERBATIM);
          seen_end = 1;
          break;
        }

      if (html && character == '&' && escape_html)
        add_word ("&amp;");
      else if (html && character == '<' && escape_html)
        add_word ("&lt;");
      else
        add_char (character);

      input_text_offset++;
    }

  if (find_end_verbatim && !seen_end)
    warning (_("end of file inside verbatim block"));

  if (html)
    add_word ("</pre>");
  
  in_fixed_width_font--;
  filling_enabled = save_filling_enabled;
  inhibit_paragraph_indentation = save_inhibit_paragraph_indentation;
}

void
cm_verbatim ()
{
  handle_verbatim_environment (1);
}

void
cm_table ()
{
  begin_insertion (table);
}

void
cm_multitable ()
{
  begin_insertion (multitable); /* @@ */
}

void
cm_ftable ()
{
  begin_insertion (ftable);
}

void
cm_vtable ()
{
  begin_insertion (vtable);
}

void
cm_group ()
{
  begin_insertion (group);
}

/* Insert raw HTML (no escaping of `<' etc.). */
void
cm_html ()
{
  if (process_html || process_xml)
    begin_insertion (rawhtml);
  else
    command_name_condition ();
}

void
cm_ifhtml ()
{
  if (process_html)
    begin_insertion (ifhtml);
  else
    command_name_condition ();
}

void
cm_ifnothtml ()
{
  if (!process_html)
    begin_insertion (ifnothtml);
  else
    command_name_condition ();
}


void
cm_ifinfo ()
{
  if (process_info)
    begin_insertion (ifinfo);
  else
    command_name_condition ();
}

void
cm_ifnotinfo ()
{
  if (!process_info)
    begin_insertion (ifnotinfo);
  else
    command_name_condition ();
}


void
cm_ifplaintext ()
{
  if (process_plaintext)
    begin_insertion (ifplaintext);
  else
    command_name_condition ();
}

void
cm_ifnotplaintext ()
{
  if (!process_plaintext)
    begin_insertion (ifnotplaintext);
  else
    command_name_condition ();
}


void
cm_tex ()
{
  if (process_tex)
    begin_insertion (rawtex);
  else
    command_name_condition ();
}

void
cm_iftex ()
{
  if (process_tex)
    begin_insertion (iftex);
  else
    command_name_condition ();
}

void
cm_ifnottex ()
{
  if (!process_tex)
    begin_insertion (ifnottex);
  else
    command_name_condition ();
}

void
cm_ifxml ()
{
  if (process_xml)
    begin_insertion (ifxml);
  else
    command_name_condition ();
}

void
cm_ifnotxml ()
{
  if (!process_xml)
    begin_insertion (ifnotxml);
  else
    command_name_condition ();
}


/* Begin an insertion where the lines are not filled or indented. */
void
cm_flushleft ()
{
  begin_insertion (flushleft);
}

/* Begin an insertion where the lines are not filled, and each line is
   forced to the right-hand side of the page. */
void
cm_flushright ()
{
  begin_insertion (flushright);
}

void
cm_menu ()
{
  if (current_node == NULL)
    {
      warning (_("@menu seen before first @node, creating `Top' node"));
      warning (_("perhaps your @top node should be wrapped in @ifnottex rather than @ifinfo?"));
      /* Include @top command so we can construct the implicit node tree.  */
      execute_string ("@node top\n@top Top\n");
    }
  begin_insertion (menu);
}

void
cm_detailmenu ()
{
  if (current_node == NULL)
    { /* Problems anyway, @detailmenu should always be inside @menu.  */
      warning (_("@detailmenu seen before first node, creating `Top' node"));
      execute_string ("@node top\n@top Top\n");
    }
  begin_insertion (detailmenu);
}

/* End existing insertion block. */
void
cm_end ()
{
  char *temp;
  enum insertion_type type;

  if (!insertion_level)
    {
      line_error (_("Unmatched `%c%s'"), COMMAND_PREFIX, command);
      return;
    }

  get_rest_of_line (0, &temp);

  if (temp[0] == 0)
    line_error (_("`%c%s' needs something after it"), COMMAND_PREFIX, command);

  type = find_type_from_name (temp);

  if (type == bad_type)
    {
      line_error (_("Bad argument to `%s', `%s', using `%s'"),
           command, temp, insertion_type_pname (current_insertion_type ()));
    }
  if (xml && type == menu) /* fixme */
    {
      xml_end_menu ();
    }
  end_insertion (type);
  free (temp);
}

/* @itemx, @item. */

static int itemx_flag = 0;

/* Return whether CMD takes a brace-delimited {arg}.  */
/*static */int
command_needs_braces (cmd)
     char *cmd;
{
  int i;
  for (i = 0; command_table[i].name; i++)
    {
      if (STREQ (command_table[i].name, cmd))
        return command_table[i].argument_in_braces == BRACE_ARGS;
    }

  return 0; /* macro or alias */
}


void
cm_item ()
{
  char *rest_of_line, *item_func;

  /* Can only hack "@item" while inside of an insertion. */
  if (insertion_level)
    {
      INSERTION_ELT *stack = insertion_stack;
      int original_input_text_offset;

      skip_whitespace ();
      original_input_text_offset = input_text_offset;

      get_rest_of_line (0, &rest_of_line);
      item_func = current_item_function ();

    /* Do the right thing depending on which insertion function is active. */
    switch_top:
      switch (stack->insertion)
        {
        case multitable:
          multitable_item ();
          /* Support text directly after the @item.  */
          if (*rest_of_line)
            {
              line_number--;
              input_text_offset = original_input_text_offset;
            }
          break;

        case ifclear:
        case ifhtml:
        case ifinfo:
        case ifnothtml:
        case ifnotinfo:
        case ifnotplaintext:
        case ifnottex:
	case ifnotxml:
        case ifplaintext:
        case ifset:
        case iftex:
	case ifxml:
        case rawhtml:
        case rawtex:
        case tex:
        case cartouche:
          stack = stack->next;
          if (!stack)
            goto no_insertion;
          else
            goto switch_top;
          break;

        case menu:
        case quotation:
        case example:
        case smallexample:
        case lisp:
        case smalllisp:
        case format:
        case smallformat:
        case display:
        case smalldisplay:
        case group:
          line_error (_("@%s not meaningful inside `@%s' block"),
                      command,
                      insertion_type_pname (current_insertion_type ()));
          break;

        case itemize:
        case enumerate:
          if (itemx_flag)
            {
              line_error (_("@itemx not meaningful inside `%s' block"),
                          insertion_type_pname (current_insertion_type ()));
            }
          else
            {
              if (html)
                {
                  if (in_paragraph)
                    {
                      add_word ("</p>");
                      in_paragraph = 0;
                    }
                  add_word ("<li>");
                }
              else if (xml)
                xml_begin_item ();
              else
                {
                  start_paragraph ();
                  kill_self_indent (-1);
                  filling_enabled = indented_fill = 1;

                  if (current_item_function ())
                    {
                      output_column = current_indent - 2;
                      indent (output_column);

                      /* The item marker can be given with or without
                         braces -- @bullet and @bullet{} are both ok.
                         Or it might be something that doesn't take
                         braces at all, such as "o" or "#" or "@ ".
                         Thus, only supply braces if the item marker is
                         a command, they haven't supplied braces
                         themselves, and we know it needs them.  */
                      if (item_func && *item_func)
                        {
                          if (*item_func == COMMAND_PREFIX
                              && item_func[strlen (item_func) - 1] != '}'
                              && command_needs_braces (item_func + 1))
                            execute_string ("%s{}", item_func);
                          else
                            execute_string ("%s", item_func);
                        }
                      insert (' ');
                      output_column++;
                    }
                  else
                    enumerate_item ();

                  /* Special hack.  This makes `close_paragraph' a no-op until
                     `start_paragraph' has been called. */
                  must_start_paragraph = 1;
                }

              /* Handle text directly after the @item.  */
              if (*rest_of_line)
                {
                  line_number--;
                  input_text_offset = original_input_text_offset;
                }
            }
          break;

        case table:
        case ftable:
        case vtable:
          if (html)
            {
              static int last_html_output_position = 0;

              /* If nothing has been output since the last <dd>,
                 remove the empty <dd> element.  Some browsers render
                 an extra empty line for <dd><dt>, which makes @itemx
                 conversion look ugly.  */
              if (last_html_output_position == output_position
                  && strncmp ((char *) output_paragraph, "<dd>",
                                output_paragraph_offset) == 0)
                output_paragraph_offset = 0;

              /* Force the browser to render one blank line before
                 each new @item in a table.  But don't do that if
                 this is the first <dt> after the <dl>, or if we are
                 converting @itemx.

                 Note that there are some browsers which ignore <br>
                 in this context, but I cannot find any way to force
                 them all render exactly one blank line.  */
              if (!itemx_flag
                  && ((output_paragraph_offset < sizeof (dl_tag) + 1)
                     || strncmp ((char *) output_paragraph
                              + output_paragraph_offset - sizeof (dl_tag) + 1, 
                              dl_tag, sizeof (dl_tag) - 1) != 0))
                add_word ("<br>");
   
              add_word ("<dt>");
              if (item_func && *item_func)
                execute_string ("%s{%s}", item_func, rest_of_line);
              else
                execute_string ("%s", rest_of_line);

              if (current_insertion_type () == ftable)
                execute_string ("%cfindex %s\n", COMMAND_PREFIX, rest_of_line);

              if (current_insertion_type () == vtable)
                execute_string ("%cvindex %s\n", COMMAND_PREFIX, rest_of_line);
              /* Make sure output_position is updated, so we could
                 remember it.  */
              close_single_paragraph ();
              last_html_output_position = output_position;
              add_word ("<dd>");
            }
          else if (xml) /* && docbook)*/ /* 05-08 */
            {
              xml_begin_table_item ();
              if (item_func && *item_func)
                execute_string ("%s{%s}", item_func, rest_of_line);
              else
                execute_string ("%s", rest_of_line);
              xml_continue_table_item ();
            }
          else
            {
              /* We need this to determine if we have two @item's in a row
                 (see test just below).  */
              static int last_item_output_position = 0;

              /* Get rid of extra characters. */
              kill_self_indent (-1);

              /* If we have one @item followed directly by another @item,
                 we need to insert a blank line.  This is not true for
                 @itemx, though.  */
              if (!itemx_flag && last_item_output_position == output_position)
                insert ('\n');

              /* `close_paragraph' almost does what we want.  The problem
                 is when paragraph_is_open, and last_char_was_newline, and
                 the last newline has been turned into a space, because
                 filling_enabled. I handle it here. */
              if (last_char_was_newline && filling_enabled &&
                  paragraph_is_open)
                insert ('\n');
              close_paragraph ();

#if defined (INDENT_PARAGRAPHS_IN_TABLE)
              /* Indent on a new line, but back up one indentation level. */
              {
                int save = inhibit_paragraph_indentation;
                inhibit_paragraph_indentation = 1;
                /* At this point, inserting any non-whitespace character will
                   force the existing indentation to be output. */
                add_char ('i');
                inhibit_paragraph_indentation = save;
              }
#else /* !INDENT_PARAGRAPHS_IN_TABLE */
              add_char ('i');
#endif /* !INDENT_PARAGRAPHS_IN_TABLE */

              output_paragraph_offset--;
              kill_self_indent (default_indentation_increment + 1);

              /* Add item's argument to the line. */
              filling_enabled = 0;
              if (item_func && *item_func)
                execute_string ("%s{%s}", item_func, rest_of_line);
              else
                execute_string ("%s", rest_of_line);

              if (current_insertion_type () == ftable)
                execute_string ("%cfindex %s\n", COMMAND_PREFIX, rest_of_line);
              else if (current_insertion_type () == vtable)
                execute_string ("%cvindex %s\n", COMMAND_PREFIX, rest_of_line);

              /* Start a new line, and let start_paragraph ()
                 do the indenting of it for you. */
              close_single_paragraph ();
              indented_fill = filling_enabled = 1;
              last_item_output_position = output_position;
            }
        }
      free (rest_of_line);
    }
  else
    {
    no_insertion:
      line_error (_("%c%s found outside of an insertion block"),
                  COMMAND_PREFIX, command);
    }
}

void
cm_itemx ()
{
  itemx_flag++;
  cm_item ();
  itemx_flag--;
}