const char *zTkt = P("tkt");
  const char *zFrom = P("from");
  const char *aContent = P("f");
  const char *zName = PD("f:filename","unknown");
  const char *zTarget;
  const char *zTargetType;
  int szContent = atoi(PD("f:bytes","0"));
  int goodCaptcha = 1;

  if( P("cancel") ) cgi_redirect(zFrom);
  if( zPage && zTkt ) fossil_redirect_home();
  if( zPage==0 && zTkt==0 ) fossil_redirect_home();
  login_check_credentials();
  if( zPage ){
    if( g.perm.ApndWiki==0 || g.perm.Attach==0 ) login_needed();

    zTargetType = mprintf("Ticket <a href=\"%s/tktview/%S\">%S</a>",
                          g.zTop, zTkt, zTkt);
  }
  if( zFrom==0 ) zFrom = mprintf("%s/home", g.zTop);
  if( P("cancel") ){
    cgi_redirect(zFrom);
  }
  if( P("ok") && szContent>0 && (goodCaptcha = captcha_is_correct()) ){
    Blob content;
    Blob manifest;
    Blob cksum;
    char *zUUID;
    const char *zComment;
    char *zDate;
    int rid;

    blob_appendf(&manifest, "Z %b\n", &cksum);
    attach_put(&manifest, rid, needModerator);
    assert( blob_is_reset(&manifest) );
    db_end_transaction(0);
    cgi_redirect(zFrom);
  }
  style_header("Add Attachment");
  if( !goodCaptcha ){
    @ <p class="generalError">Error: Incorrect security code.</p>
  }
  @ <h2>Add Attachment To %s(zTargetType)</h2>
  form_begin("enctype='multipart/form-data'", "%R/attachadd");
  @ <div>
  @ File to Attach:
  @ <input type="file" name="f" size="60" /><br />
  @ Description:<br />
  @ <textarea name="comment" cols="80" rows="5" wrap="virtual"></textarea><br />
  if( zTkt ){
    @ <input type="hidden" name="tkt" value="%h(zTkt)" />
  }else{
    @ <input type="hidden" name="page" value="%h(zPage)" />
  }
  @ <input type="hidden" name="from" value="%h(zFrom)" />
  @ <input type="submit" name="ok" value="Add Attachment" />
  @ <input type="submit" name="cancel" value="Cancel" />
  @ </div>
  captcha_generate();
  @ </form>
  style_footer();
}

/*
** WEBPAGE: ainfo
** URL: /ainfo?name=ARTIFACTID
**

  blob_appendf(&b, "%s-%x", zSecret, seed);
  sha1sum_blob(&b, &b);
  z = blob_buffer(&b);
  memcpy(zRes, z, 8);
  zRes[8] = 0;
  return zRes;
}

/*
** Return true if a CAPTCHA is required.
*/
int captcha_needed(void){
  if( g.zLogin!=0 ) return 0;
  return db_get_boolean("require-captcha", 1);
}

/*
** If a captcha is required but the correct captcha code is not supplied
** in the query parameters, then return false (0).  
**
** If no captcha is required or if the correct captcha is supplied, return
** true (non-zero).
*/
int captcha_is_correct(void){
  const char *zSeed;
  const char *zEntered;
  const char *zDecode;
  if( !captcha_needed() ){
    return 1;  /* No captcha needed */
  }
  zSeed = P("captchaseed");
  if( zSeed==0 ) return 0;
  zEntered = P("captcha");
  if( zEntered==0 || strlen(zEntered)!=8 ) return 0;
  zDecode = captcha_decode((unsigned int)atoi(zSeed));
  if( strcmp(zDecode,zEntered)!=0 ) return 0;
  return 1;
}

/*
** Generate a new CAPTCHA seed.  Write it as a hidden variable named
** "captchaseed".  Then return the rendered captcha text.
*/
void captcha_generate(void){
  unsigned int uSeed;
  const char *zDecoded;
  char *zCaptcha;

  if( !captcha_needed() ) return;
  uSeed = captcha_seed();
  zDecoded = captcha_decode(uSeed);
  zCaptcha = captcha_render(zDecoded);
  @ <div class="captcha"><table class="captcha"><tr><td><pre>
  @ %h(zCaptcha)
  @ </pre>
  @ Enter security code shown above:
  @ <input type="hidden" name="captchaseed" value="%u(uSeed)" />
  @ <input type="text" name="captcha" size=8 />
  @ </td></tr></table></div>
}

  @
  @ <p>You do not normally want a bot to walk your entire repository because
  @ if it does, your server will end up computing diffs and annotations for
  @ every historical version of every file and creating ZIPs and tarballs of
  @ every historical check-in, which can use a lot of CPU and bandwidth
  @ even for relatively small projects.</p>

  @ <hr />
  onoff_attribute("Require a CAPTCHA if not logged in",
                  "require-captcha", "reqcapt", 1);
  @ <p>Require a CAPTCHA for edit operations (appending, creating, or
  @ editing wiki or tickets or adding attachments to wiki or tickets)
  @ for users who are not logged in.</p>

  @ <hr />
  entry_attribute("Public pages", 30, "public-pages",
                  "pubpage", "");
  @ <p>A comma-separated list of glob patterns for pages that are accessible
  @ without needing a login and using the privileges given by the
  @ "Default privileges" setting below.  Example use case: Set this field
  @ to "/doc/trunk/www/*" to give anonymous users read-only permission to the 
  @ latest version of the embedded documentation in the www/ folder without
  @ allowing them to see the rest of the source code.
  @ </p>


  @ <hr />
  onoff_attribute("Allow users to register themselves",
                  "self-register", "selfregister", 0);
  @ <p>Allow users to register themselves through the HTTP UI. 
  @ The registration form always requires filling in a CAPTCHA 
  @ (<em>auto-captcha</em> setting is ignored). Still, bear in mind that anyone

    @   margin-right: 10px;
    @   margin-left: 10px;
    @   margin-top: 10px;
  },
  { "div.captcha",
    "captcha display options",
    @   text-align: center;
    @   padding: 1ex;
  },
  { "table.captcha",
    "format for the layout table, used for the captcha display",
    @   margin: auto;
    @   padding: 10px;
    @   border-width: 4px;
    @   border-style: double;

  char *zDate;
  const char *zUuid;
  int i;
  int nJ = 0;
  Blob tktchng, cksum;

  login_verify_csrf_secret();
  if( !captcha_is_correct() ){
    @ <p class="generalError">Error: Incorrect security code.</p>
    return TH_OK;
  }
  zUuid = (const char *)pUuid;
  blob_zero(&tktchng);
  zDate = date_in_standard_format("now");
  blob_appendf(&tktchng, "D %s\n", zDate);
  free(zDate);
  for(i=0; i<nField; i++){
    if( azAppend[i] ){

  form_begin(0, "%R/%s", g.zPath);
  login_insert_csrf_secret();
  if( P("date_override") && g.perm.Setup ){
    @ <input type="hidden" name="date_override" value="%h(P("date_override"))">
  }
  @ </p>
  zScript = ticket_newpage_code();
  Th_Store("login", g.zLogin ? g.zLogin : "nobody");
  Th_Store("date", db_text(0, "SELECT datetime('now')"));
  Th_CreateCommand(g.interp, "submit_ticket", submitTicketCmd,
                   (void*)&zNewUuid, 0);
  if( g.thTrace ) Th_Trace("BEGIN_TKTNEW_SCRIPT<br />\n", -1);
  if( Th_Render(zScript)==TH_RETURN && !g.thTrace && zNewUuid ){
    cgi_redirect(mprintf("%s/tktview/%s", g.zTop, zNewUuid));
    return;
  }
  captcha_generate();
  @ </form>
  if( g.thTrace ) Th_Trace("END_TKTVIEW<br />\n", -1);
  style_footer();
}

/*
** WEBPAGE: tktedit

  initializeVariablesFromCGI();
  initializeVariablesFromDb();
  form_begin(0, "%R/%s", g.zPath);
  @ <input type="hidden" name="name" value="%s(zName)" />
  login_insert_csrf_secret();
  @ </p>
  zScript = ticket_editpage_code();
  Th_Store("login", g.zLogin ? g.zLogin : "nobody");
  Th_Store("date", db_text(0, "SELECT datetime('now')"));
  Th_CreateCommand(g.interp, "append_field", appendRemarkCmd, 0, 0);
  Th_CreateCommand(g.interp, "submit_ticket", submitTicketCmd, (void*)&zName,0);
  if( g.thTrace ) Th_Trace("BEGIN_TKTEDIT_SCRIPT<br />\n", -1);
  if( Th_Render(zScript)==TH_RETURN && !g.thTrace && zName ){
    cgi_redirect(mprintf("%s/tktview/%s", g.zTop, zName));
    return;
  }
  captcha_generate();
  @ </form>
  if( g.thTrace ) Th_Trace("BEGIN_TKTEDIT<br />\n", -1);
  style_footer();
}

/*
** Check the ticket table schema in zSchema to see if it appears to

  Blob wiki;
  Manifest *pWiki = 0;
  const char *zPageName;
  int n;
  const char *z;
  char *zBody = (char*)P("w");
  int isWysiwyg = P("wysiwyg")!=0;
  int goodCaptcha = 1;

  if( P("edit-wysiwyg")!=0 ){ isWysiwyg = 1; zBody = 0; }
  if( P("edit-markup")!=0 ){ isWysiwyg = 0; zBody = 0; }
  if( zBody ){
    if( isWysiwyg ){
      Blob body;
      blob_zero(&body);

      login_needed();
      return;
    }
    if( zBody==0 && (pWiki = manifest_get(rid, CFTYPE_WIKI))!=0 ){
      zBody = pWiki->zWiki;
    }
  }
  if( P("submit")!=0 && zBody!=0
   && (goodCaptcha = captcha_is_correct())
  ){
    char *zDate;
    Blob cksum;
    blob_zero(&wiki);
    db_begin_transaction();
    if( isSandbox ){
      db_set("sandbox",zBody,0);
    }else{

    return;
  }
  if( zBody==0 ){
    zBody = mprintf("<i>Empty Page</i>");
  }
  style_set_current_page("%s?name=%T", g.zPath, zPageName);
  style_header("Edit: %s", zPageName);
  if( !goodCaptcha ){
    @ <p class="generalError">Error:  Incorrect security code.</p>
  }
  blob_zero(&wiki);
  blob_append(&wiki, zBody, -1);
  if( P("preview")!=0 ){
    @ Preview:<hr />
    wiki_convert(&wiki, 0, 0);
    @ <hr />
    blob_reset(&wiki);

    blob_reset(&temp);
    wysiwygEditor("w", blob_str(&html), 60, n);
    blob_reset(&html);
    @ <br />
    @ <input type="submit" name="edit-markup" value="Markup Editor"
    @  onclick='return confirm("Switching to markup-mode\nwill erase your WYSIWYG\nedits. Continue?")' />
  }

  login_insert_csrf_secret();
  @ <input type="submit" name="submit" value="Apply These Changes" />
  @ <input type="hidden" name="name" value="%h(zPageName)" />
  @ <input type="submit" name="cancel" value="Cancel"
  @  onclick='confirm("Abandon your changes?")' />
  @ </div>
  captcha_generate();
  @ </form>
  manifest_destroy(pWiki);
  blob_reset(&wiki);
  style_footer();
}

/*
** WEBPAGE: wikinew

*/
void wikiappend_page(void){
  char *zTag;
  int rid = 0;
  int isSandbox;
  const char *zPageName;
  const char *zUser;
  int goodCaptcha = 1;

  login_check_credentials();
  zPageName = PD("name","");
  if( check_name(zPageName) ) return;
  isSandbox = is_sandbox(zPageName);
  if( !isSandbox ){
    zTag = mprintf("wiki-%s", zPageName);

      return;
    }
  }
  if( !g.perm.ApndWiki ){
    login_needed();
    return;
  }
  if( P("submit")!=0 && P("r")!=0 && P("u")!=0
   && (goodCaptcha = captcha_is_correct())
  ){
    char *zDate;
    Blob cksum;
    Blob body;
    Blob wiki;
    Manifest *pWiki = 0;

    blob_zero(&body);

  }
  if( P("cancel")!=0 ){
    cgi_redirectf("wiki?name=%T", zPageName);
    return;
  }
  style_set_current_page("%s?name=%T", g.zPath, zPageName);
  style_header("Append Comment To: %s", zPageName);
  if( !goodCaptcha ){
    @ <p class="generalError">Error: Incorrect security code.</p>
  }
  if( P("preview")!=0 ){
    Blob preview;
    blob_zero(&preview);
    appendRemark(&preview);
    @ Preview:<hr>
    wiki_convert(&preview, 0, 0);
    @ <hr>

  @ Comment to append:<br />
  @ <textarea name="r" class="wikiedit" cols="80" 
  @  rows="10" wrap="virtual">%h(PD("r",""))</textarea>
  @ <br />
  @ <input type="submit" name="preview" value="Preview Your Comment" />
  @ <input type="submit" name="submit" value="Append Your Changes" />
  @ <input type="submit" name="cancel" value="Cancel" />
  captcha_generate();
  @ </form>
  style_footer();
}

/*
** Name of the wiki history page being generated
*/