/*
 * xman - X window system manual page display program.
 *
 * $XConsortium: search.c,v 1.20 91/07/21 21:28:09 rws Exp $
 *
 * Copyright 1987, 1988 Massachusetts Institute of Technology
 *
 * Permission to use, copy, modify, and distribute this software and its
 * documentation for any purpose and without fee is hereby granted, provided
 * that the above copyright notice appear in all copies and that both that
 * copyright notice and this permission notice appear in supporting
 * documentation, and that the name of M.I.T. not be used in advertising or
 * publicity pertaining to distribution of the software without specific,
 * written prior permission.  M.I.T. makes no representations about the
 * suitability of this software for any purpose.  It is provided "as is"
 * without express or implied warranty.
 *
 * Author:    Chris D. Peterson, MIT Project Athena
 * Created:   November 3, 1987
 */

#include "globals.h"
#include "vendor.h"

/* Map <CR> and control-M to goto begining of file. */

#define SEARCHARGS 10

FILE * DoManualSearch();
static int BEntrySearch();

/*	Function Name: MakeSearchWidget
 *	Description: This Function Creates the Search Widget.
 *	Arguments: man_globals - the pseudo globas for this manpage.
 *                 w - the widgets parent
 *	Returns: the search widget.
 */

void
MakeSearchWidget(man_globals, parent)
ManpageGlobals * man_globals;
Widget parent;
{
  Widget dialog, command, text, cancel;
  Arg arglist[1];
  Cardinal num_args = 0;

  XtSetArg(arglist[0], XtNtransientFor, parent); 
  man_globals->search_widget = XtCreatePopupShell(SEARCHNAME, 
						  transientShellWidgetClass, 
						  parent,
						  arglist, 1);

  if (resources.clear_search_string) {
    XtSetArg(arglist[0], XtNvalue, ""); num_args++;  
  }

  dialog = XtCreateManagedWidget(DIALOG, dialogWidgetClass,
				 man_globals->search_widget, 
				 arglist, num_args);

  if ( (text = XtNameToWidget(dialog, "value")) == (Widget) NULL)
    PopupWarning(NULL, "Could not find text widget in MakeSearchWidget.");
  else
    XtSetKeyboardFocus(dialog, text);

  XawDialogAddButton(dialog, MANUALSEARCH, NULL, NULL);
  XawDialogAddButton(dialog, APROPOSSEARCH, NULL, NULL);
  XawDialogAddButton(dialog, CANCEL, NULL, NULL);

/*
 * This is a bit gross, but it get the cancel button underneath the 
 * others, and forms them up to the right size..
 */

  if ( ((command = XtNameToWidget(dialog, MANUALSEARCH)) == (Widget) NULL) ||
       ((cancel = XtNameToWidget(dialog, CANCEL)) == (Widget) NULL) )
    PopupWarning(NULL,
		 "Could not find manual search widget in MakeSearchWidget.");
  else {
    Cardinal num_args = 0;
    Arg arglist[2];
    static char * half_size[] = {
      MANUALSEARCH, APROPOSSEARCH, NULL
    };
    static char * full_size[] = {
      "label", "value", CANCEL, NULL
    };

    XtSetArg(arglist[num_args], XtNfromVert, command); num_args++;
    XtSetArg(arglist[num_args], XtNfromHoriz, NULL); num_args++;
    XtSetValues(cancel, arglist, num_args);
    FormUpWidgets(dialog, full_size, half_size);
  }

}

/*      Function Name: SearchString
 *      Description: Returns the search string.
 *      Arguments: man_globals - the globals.
 *      Returns: the search string.
 */

static char *
SearchString(man_globals)
ManpageGlobals * man_globals;
{
  Widget dialog;

  dialog = XtNameToWidget(man_globals->search_widget, DIALOG);
  if (dialog != NULL) 
    return(XawDialogGetValueString(dialog));

  PopupWarning(man_globals,
	      "Could not get the search string, no search will be preformed.");
  return(NULL);
}

  
/*	Function Name: DoSearch
 *	Description: This function performs a search for a man page or apropos
 *                   search upon search string.
 *	Arguments: man_globals - the pseudo globas for this manpage.
 *                 type - the type of search.
 *	Returns: none.
 */

#define LOOKLINES 6

/* 
 * Manual searches look through the list of manual pages for the right one
 * with a binary search.
 *
 * Apropos searches still exec man -k.
 *
 * If nothing is found then I send a warning message to the user, and do
 * nothing.
 */

FILE *
DoSearch(man_globals,type)
ManpageGlobals * man_globals;
int type;
{
  char cmdbuf[BUFSIZ],*mantmp,*manpath;
  char tmp[BUFSIZ],path[BUFSIZ];
  char string_buf[BUFSIZ], cmp_str[BUFSIZ], error_buf[BUFSIZ];
  char * search_string = SearchString(man_globals);
  FILE * file;
  int count;
  Boolean flag;

  if (search_string == NULL) return(NULL);

  /* If the string is empty or starts with a space then do not search */

  if ( streq(search_string,"") ) {
    PopupWarning(man_globals, "Search string is empty.");
    return(NULL);
  }

  if (search_string[0] == ' ') {
    PopupWarning(man_globals, "First character cannot be a space.");
    return(NULL);
  }

  strcpy(tmp, MANTEMP);		/* get a temp file. */
  (void) mktemp(tmp);
  mantmp = tmp;

  /* set the command */

  manpath=getenv("MANPATH");
  if (manpath == NULL || streq(manpath,"") ) {
    strcpy(path,SYSMANPATH);
#ifdef LOCALMANPATH
    strcat(path,":");
    strcat(path,LOCALMANPATH);
#endif
  } else {
    strcpy(path,manpath);
  }

  if (type == APROPOS) {
    char label[BUFSIZ];

    sprintf(label,"Results of apropos search on: %s", search_string);

#ifdef NO_MANPATH_SUPPORT	/* not quite correct, but the best I can do. */
    sprintf(cmdbuf, APROPOS_FORMAT, search_string, mantmp);
#else
    sprintf(cmdbuf, APROPOS_FORMAT, path, search_string, mantmp);
#endif

    if(system(cmdbuf) != 0) {	/* execute search. */
      sprintf(error_buf,"Something went wrong trying to run %s\n",cmdbuf);
      PopupWarning(man_globals, error_buf);
    }

    if((file = fopen(mantmp,"r")) == NULL)
      PrintError("lost temp file? out of temp space?");

/* 
 * Since we keep the FD open we can unlink the file safely, this
 * will keep extra files out of /tmp. 
 */

    unlink(mantmp);

    sprintf(string_buf,"%s: nothing appropriate", search_string);

    /*
     * Check first LOOKLINES lines for "nothing appropriate".
     */
  
    count = 0;
    flag = FALSE;
    while ( (fgets(cmp_str, BUFSIZ, file) != NULL) && (count < LOOKLINES) ) {
      if ( cmp_str[strlen(cmp_str) - 1] == '\n') /* strip off the '\n' */
	  cmp_str[strlen(cmp_str) - 1] = '\0';

      if (streq(cmp_str, string_buf)) {
	flag = TRUE;
	break;
      }
      count++;
    }

    /*
     * If the file is less than this number of lines then assume that there is
     * nothing apropriate found. This does not confuse the apropos filter.
     */

    if (flag) {
      fclose(file);
      file = NULL;
      ChangeLabel(man_globals->label,string_buf);
      return(NULL);
    }
  
    strcpy(man_globals->manpage_title,label);
    ChangeLabel(man_globals->label,label);
    fseek(file, 0L, 0);		/* reset file to point at top. */
  }
  else {			/* MANUAL SEACH */
    file = DoManualSearch(man_globals, search_string);
    if (file == NULL) {
      sprintf(string_buf,"No manual entry for %s.", search_string);
      ChangeLabel(man_globals->label, string_buf);
      if (man_globals->label == NULL)
	PopupWarning(man_globals, string_buf);
      return(NULL);
    }
  }

  if (resources.clear_search_string) {
    Arg arglist[1];
    Widget dialog;

    dialog = XtNameToWidget(man_globals->search_widget, DIALOG);
    if (dialog == NULL) 
      PopupWarning(man_globals, "Could not clear the search string.");

    XtSetArg(arglist[0], XtNvalue, "");
    XtSetValues(dialog, arglist, (Cardinal) 1);
  }

  return(file);
}

/*	Function Name: DoManualSearch
 *	Description: performs a manual search.
 *	Arguments: man_globals - the manual page specific globals.
 *	Returns: the filename of the man page.
 */

#define NO_ENTRY -100

FILE * 
DoManualSearch(man_globals, string)
ManpageGlobals *man_globals;
char * string;
{
  int e_num = NO_ENTRY;
  int i;

/* search current section first. */
  
  i = man_globals->current_directory;
  e_num = BEntrySearch(string, manual[i].entries, manual[i].nentries);

/* search other sections. */

  if (e_num == NO_ENTRY) {
    i = 0;			/* At the exit of the loop i needs to
				   be the one we used. */
    while ( TRUE ) {
      if (i == man_globals->current_directory)
	if (++i >= sections) return(NULL);
      e_num = BEntrySearch(string, manual[i].entries, manual[i].nentries);
      if (e_num != NO_ENTRY) break;
      if (++i >= sections) return(NULL);
    }

/*
 * Manual page found in some other section, unhighlight the current one.
 */
    if ( man_globals->manpagewidgets.box != NULL)
      XawListUnhighlight(
	man_globals->manpagewidgets.box[man_globals->current_directory]);
  }
  else {
    /* 
     * Highlight the element we are searching for if it is in the directory
     * listing currently being shown.
     */
    if ( man_globals->manpagewidgets.box != NULL)
      XawListHighlight(man_globals->manpagewidgets.box[i], e_num);
  }
  return(FindManualFile(man_globals, i, e_num));
}

/*	Function Name: BEntrySearch
 *	Description: binary search through entries.
 *	Arguments: string - the string to match.
 *                 first - the first entry in the list.
 *                 number - the number of entries.
 *	Returns: a pointer to the entry found.
 */

static int
BEntrySearch(string, first, number)
char * string;
char ** first;
int number;
{
  int check, cmp, len_cmp, global_number;
  char *head, *tail;
  
  global_number = 0;
  while (TRUE) {

    if (number == 0) {
      return(NO_ENTRY);		/* didn't find it. */
    }

    check = number/2;

    head = rindex(first[ global_number + check ], '/');
    if (head == NULL) 
      PrintError("index failure in BEntrySearch");
    head++;

    tail = rindex(head, '.');
    if (tail == NULL) 
      /* not an error, some systems (e.g. sgi) have only a .z suffix */
      tail = head + strlen(head);

    cmp = strncmp(string, head, (tail - head));
    len_cmp = strlen(string) - (int) (tail - head);

    if ( cmp == 0 && len_cmp == 0) {
      return(global_number + check);
    }
    else if ( cmp < 0 || ((cmp == 0) && (len_cmp < 0)) ) 
      number = check;
    else /* cmp > 0 || ((cmp == 0) && (len_cmp > 0)) */ {
      global_number += (check + 1);
      number -= ( check + 1 );
    }
  }
}