File Content: captcha.js (function($, d, w, undefined) { var captcha_session, doing_ajax = false, flag = 0, // 0 = nothing, 1 = ok, -1 = ko, 2 = -1 + return to start numImgs = 9; // Shorthand to tell if a modifier key is pressed. function secupressHasModifierKey( e ) { return e.altKey || e.ctrlKey || e.metaKey || e.shiftKey; } // Shorthand to tell if the pressed key is Space or Enter. function secupressIsSpaceOrEnterKey( e ) { return ( e.which === 13 || e.which === 32 ) && ! secupressHasModifierKey( e ); } function secupress_sleep( millis ) { var date = new Date(), curDate = null; do { curDate = new Date(); } while( curDate-date < millis ); } function secupress_captcha_do_fail() { $( "span.checkme" ).css( "background-position", "28px 0px" ); $( "#captcha_token" ).val( "" ); $( "#msg" ).show(); } function secupress_set_flag_ok() { numImgs = 20; flag = 1; } function secupress_set_captcha_timeout() { captcha_session = setTimeout( secupress_captcha_do_fail, 1000 * 59 * 2 ); // ~2 mn } function secupress_clear_captcha_timeout() { clearTimeout( captcha_session ); } $( ".checkme" ).on( "click keyup", function( e ) { var animation, imgHeight = 28, cont = 1, inc = 1, bgposx = 0, bgposy = 0, ajaxurlsep = w.spCaptchaL10n.ajaxurl.indexOf( "?" ) !== -1 ? "&" : "?"; if ( doing_ajax || 0 !== flag ) { return; } if ( "keyup" === e.type && ! secupressIsSpaceOrEnterKey( e ) ) { return false; } animation = setInterval( function() { // Switch ajax state. switch ( flag ) { case 1: bgposx = -28; break; case -1: bgposx = 28; break; case 0: bgposx = 0; break; } // Position of the css checkbox. bgposy = - ( cont * imgHeight ); $( "span.checkme" ).css( "background-position", bgposx + "px " + bgposy + "px" ); // If animation returned to start. if ( cont === 0 ) { inc = 1; if ( flag === 2 ) { clearInterval( animation ); } } // If animation hits the end. if ( cont === numImgs ) { switch( flag ) { case 0: inc = -1; break; case 1: clearInterval( animation ); break; case -1: secupress_sleep( 2000 ); flag = 2; inc = -1; break; } } // Inc/Decrement. cont = cont + inc; }, 50 ); $( "#msg" ).hide(); doing_ajax = true; $.get( w.spCaptchaL10n.ajaxurl + ajaxurlsep + "action=captcha_check&oldvalue=" + $( "#captcha_key" ).val() ) .done( function( data ) { setTimeout( secupress_set_flag_ok, 2000 ); $( "#captcha_key" ).val( data.data ); secupress_clear_captcha_timeout(); secupress_set_captcha_timeout(); $( "span.checkme" ).parent().css( "cursor", "default" ); } ) .fail( function() { flag = -1; numImgs = 21; secupress_captcha_do_fail(); } ) .always( function( data ) { doing_ajax = false; } ); } ); } )(jQuery, document, window); Submit