(function($) {

$.blockUI = function(msg, css) {
    $.blockUI.impl.install(window, msg, css);
};

$.unblockUI = function() {
    $.blockUI.impl.remove(window);
};

$.fn.block = function(msg, css) {
    return this.each(function() {
		if (!this.$pos_checked) {
            if ($.css(this,"position") == 'static')
                this.style.position = 'relative';
            if ($.browser.msie) this.style.zoom = 1; // force 'hasLayout' in IE
            this.$pos_checked = 1;
        }
        $.blockUI.impl.install(this, msg, css);
    });
};


$.fn.unblock = function() {
    return this.each(function() {
        $.blockUI.impl.remove(this);
    });
};

// override these in your code to change the default messages and styles
$.blockUI.defaults = {
    // the message displayed when blocking the entire page
    pageMessage:    '<h1>Please wait...</h1>',
    // the message displayed when blocking an element
    elementMessage: '', // none
    // styles for the overlay iframe
    overlayCSS:  { backgroundColor: '#fff', opacity: '0.5' },
    // styles for the message when blocking the entire page
    pageMessageCSS:    { width:'250px', margin:'-50px 0 0 -125px', top:'50%', left:'50%', textAlign:'center', color:'#000', backgroundColor:'#fff', border:'3px solid #aaa' },
    // styles for the message when blocking an element
    elementMessageCSS: { width:'250px', padding:'10px', textAlign:'center', backgroundColor:'#fff'},
    // allow body element to be stetched in ie6
    ie6Stretch: 1,
	fixed_sim: 1
};

// the gory details
$.blockUI.impl = {
    pageBlock: null,
    op8: window.opera && window.opera.version() < 9,
    ffLinux: $.browser.mozilla && /Linux/.test(navigator.platform),
    ie6: $.browser.msie && typeof XMLHttpRequest == 'function',
    install: function(el, msg, css) {
        var full = (el == window), noalpha = this.op8 || this.ffLinux;
        if (full && this.pageBlock) this.remove(window);
        // check to see if we were only passed the css object (a literal)
        if (msg && typeof msg == 'object' && !msg.jquery && !msg.nodeType) {
            css = msg;
            msg = null;
        }
        msg = msg ? (msg.nodeType ? $(msg) : msg) : full ? $.blockUI.defaults.pageMessage : $.blockUI.defaults.elementMessage;
        var basecss = jQuery.extend({}, full ? $.blockUI.defaults.pageMessageCSS : $.blockUI.defaults.elementMessageCSS);
        css = jQuery.extend(basecss, css || {});
        var f = ($.browser.msie) ? $('<iframe class="blockUI" style="z-index:1000;border:none;margin:0;padding:0;position:absolute;width:100%;height:100%;top:0;left:0" src="javascript:false;document.write(\'\');"></iframe>')
                           : $('<div class="blockUI" style="display:none"></div>');
        var w = $('<div class="blockUI" style="z-index:1001;border:none;margin:0;padding:0;width:100%;height:100%;top:0;left:0"></div>');
        var m = full ? $('<div class="blockUI blockMsg" style="z-index:1002;padding:0;position:fixed"></div>')
                     : $('<div class="blockUI" style="display:none;z-index:1002;position:absolute"></div>');
        w.css('position', full ? 'fixed' : 'absolute');
        if (msg) m.css(css);
        if (!noalpha) w.css($.blockUI.defaults.overlayCSS);
        if (this.op8) w.css({ width:''+el.clientWidth,height:''+el.clientHeight }); // lame
        if ($.browser.msie) f.css('opacity','0.0');

        $([f[0],w[0],m[0]]).appendTo(full ? 'body' : el);
        if (full) this.pageBlock = m[0];

        // ie7 must use absolute positioning in quirks mode and to account for activex issues (when scrolling)
        var expr = $.browser.msie && (!$.boxModel || $('object,embed', full ? null : el).length > 0);
        if (this.ie6 || expr) { 
            // stretch content area if it's short
            if (full && $.blockUI.defaults.ie6Stretch && $.boxModel)
                $('html,body').css('height','100%');

            // fix ie6 problem when blocked element has a border width
            if (this.ie6 && !full) {
                var t = this.sz(el,'borderTopWidth'), l = this.sz(el,'borderLeftWidth');
                var fixT = t ? '(0 - '+t+')' : 0;
                var fixL = l ? '(0 - '+l+')' : 0;
            }
            
            // simulate fixed position
			
            $.each([f,w,m], function(i,o) {
                var s = o[0].style;
                s.position = 'absolute';
				if ($.blockUI.defaults.fixed_sim == 1) {
                if (i < 2) {
					
                    full ? s.setExpression('height','document.body.scrollHeight > document.body.offsetHeight ? document.body.scrollHeight : document.body.offsetHeight + "px"') 
                         : s.setExpression('height','this.parentNode.offsetHeight + "px"');
                    full ? s.setExpression('width','jQuery.boxModel && document.documentElement.clientWidth || document.body.clientWidth + "px"')
                         : s.setExpression('width','this.parentNode.offsetWidth + "px"');
                    if (fixL) s.setExpression('left', fixL);
                    if (fixT) s.setExpression('top', fixT);

                }
                else {
                    if (full) s.setExpression('top','(document.documentElement.clientHeight || document.body.clientHeight) / 2 - (this.offsetHeight / 2) + (blah = document.documentElement.scrollTop ? document.documentElement.scrollTop : document.body.scrollTop) + "px"')
                    s.marginTop = 0;
                }
				}
				
            });
			
        }
        this.bind(1, el);
        m.append(msg).show();
        if (msg.jquery) msg.show();
        full ? setTimeout(this.focus, 200): this.center(m[0]);
    },
    remove: function(el) {
        this.bind(0, el);
        var full = el == window;
        if (full) {
            $('body').children().filter('.blockUI').remove();
            this.pageBlock = null;
        }
        else $('.blockUI', el).remove();
    },
    // event handler to suppress keyboard/mouse events when blocking
    handler: function(e) {
        if (e.keyCode && e.keyCode == 9) return true;
        if ($(e.target).parents('div.blockMsg').length > 0)
            return true;
        return $(e.target).parents().children().filter('div.blockUI').length == 0;
    },
    // bind/unbind the handler
    bind: function(b, el) {
        var full = el == window;
        // don't bother unbinding if there is nothing to unbind
        if (!b && (full && !this.pageBlock || !full && !el.$blocked)) return;
        if (!full) el.$blocked = b;
        var $e = full ? $() : $(el).find('a,:input');
        $.each(['mousedown','mouseup','keydown','keypress','keyup','click'], function(i,o) {
            $e[b?'bind':'unbind'](o, $.blockUI.impl.handler);
        });
    },
    focus: function() {
        if (!$.blockUI.impl.pageBlock) return;
        var v = $(':input:visible:enabled', $.blockUI.impl.pageBlock)[0];
        if (v) v.focus();
    },
    center: function(el) {
		var p = el.parentNode, s = el.style;
        var l = (this.sz(p,"width") - this.sz(el,"width"))/2;
        var t = (this.sz(p,"height") - this.sz(el,"height"))/2 + this.sz(p,"paddingTop")/2;
        s.left = l > 0 ? (l+'px') : '0';
        s.top  = t > 0 ? (t+'px') : '0';
    },
    sz: function(el, p) { return parseInt($.css(el,p))||0; }
};

})(jQuery);