LAB.js

/*! LAB.js (LABjs :: Loading And Blocking JavaScript) [Error Handling Fork]
    Error Handling Fork https://github.com/jasonhinkle/LABjs-eh
    v2.0.3 (c) Kyle Simpson
    MIT License
*/
(function(global){var _$LAB=global.$LAB,_UseLocalXHR="UseLocalXHR",_AlwaysPreserveOrder="AlwaysPreserveOrder",_AllowDuplicates="AllowDuplicates",_CacheBust="CacheBust",_Debug="Debug",_BasePath="BasePath",_ErrorHandler="ErrorHandler",root_page=/^[^?#]*\//.exec(location.href)[0],root_domain=/^\w+\:\/\/\/?[^\/]+/.exec(root_page)[0],append_to=document.head||document.getElementsByTagName("head"),opera_or_gecko=(global.opera&&Object.prototype.toString.call(global.opera)=="[object Opera]")||("MozAppearance"in document.documentElement.style),log_msg=function(){},log_error=log_msg,test_script_elem=document.createElement("script"),explicit_preloading=typeof test_script_elem.preload=="boolean",real_preloading=explicit_preloading||(test_script_elem.readyState&&test_script_elem.readyState=="uninitialized"),script_ordered_async=!real_preloading&&test_script_elem.async===true,xhr_or_cache_preloading=!real_preloading&&!script_ordered_async&&!opera_or_gecko;if(global.console&&global.console.log){if(!global.console.error)global.console.error=global.console.log;log_msg=function(msg){global.console.log(msg)};log_error=function(msg,err){global.console.error(msg,err)}}function is_func(func){return Object.prototype.toString.call(func)=="[object Function]"}function is_array(arr){return Object.prototype.toString.call(arr)=="[object Array]"}function canonical_uri(src,base_path){var absolute_regex=/^\w+\:\/\//;if(/^\/\/\/?/.test(src)){src=location.protocol+src}else if(!absolute_regex.test(src)&&src.charAt(0)!="/"){src=(base_path||"")+src}return absolute_regex.test(src)?src:((src.charAt(0)=="/"?root_domain:root_page)+src)}function merge_objs(source,target){for(var k in source){if(source.hasOwnProperty(k)){target[k]=source[k]}}return target}function check_chain_group_scripts_ready(chain_group){var any_scripts_ready=false;for(var i=0;i<chain_group.scripts.length;i++){if(chain_group.scripts[i].ready&&chain_group.scripts[i].exec_trigger){any_scripts_ready=true;chain_group.scripts[i].exec_trigger();chain_group.scripts[i].exec_trigger=null}}return any_scripts_ready}function create_script_load_listener(elem,registry_item,flag,onload){elem.onload=elem.onreadystatechange=function(){if((elem.readyState&&elem.readyState!="complete"&&elem.readyState!="loaded")||registry_item[flag])return;elem.onload=elem.onreadystatechange=null;onload()}}function script_executed(registry_item){registry_item.ready=registry_item.finished=true;for(var i=0;i<registry_item.finished_listeners.length;i++){registry_item.finished_listeners[i]()}registry_item.ready_listeners=[];registry_item.finished_listeners=[]}function request_script(chain_opts,script_obj,registry_item,onload,preload_this_script){setTimeout(function(){var script,src=script_obj.real_src,xhr;if("item"in append_to){if(!append_to[0]){setTimeout(arguments.callee,25);return}append_to=append_to[0]}script=document.createElement("script");if(script_obj.type)script.type=script_obj.type;if(script_obj.charset)script.charset=script_obj.charset;if(preload_this_script){if(real_preloading){if(chain_opts[_Debug])log_msg("start script preload: "+src);registry_item.elem=script;if(explicit_preloading){script.preload=true;script.onpreload=onload}else{script.onreadystatechange=function(){if(script.readyState=="loaded")onload()}}script.src=src}else if(preload_this_script&&src.indexOf(root_domain)==0&&chain_opts[_UseLocalXHR]){xhr=new XMLHttpRequest();if(chain_opts[_Debug])log_msg("start script preload (xhr): "+src);xhr.onreadystatechange=function(){if(xhr.readyState==4){xhr.onreadystatechange=function(){};registry_item.text=xhr.responseText+"\n//@ sourceURL="+src;onload()}};xhr.open("GET",src);xhr.send()}else{if(chain_opts[_Debug])log_msg("start script preload (cache): "+src);script.type="text/cache-script";create_script_load_listener(script,registry_item,"ready",function(){append_to.removeChild(script);onload()});script.src=src;append_to.insertBefore(script,append_to.firstChild)}}else if(script_ordered_async){if(chain_opts[_Debug])log_msg("start script load (ordered async): "+src);script.async=false;create_script_load_listener(script,registry_item,"finished",onload);script.src=src;append_to.insertBefore(script,append_to.firstChild)}else{if(chain_opts[_Debug])log_msg("start script load: "+src);create_script_load_listener(script,registry_item,"finished",onload);script.src=src;append_to.insertBefore(script,append_to.firstChild)}},0)}function create_sandbox(){var global_defaults={},can_use_preloading=real_preloading||xhr_or_cache_preloading,queue=[],registry={},instanceAPI;global_defaults[_UseLocalXHR]=true;global_defaults[_AlwaysPreserveOrder]=false;global_defaults[_AllowDuplicates]=false;global_defaults[_CacheBust]=false;global_defaults[_Debug]=false;global_defaults[_BasePath]="";global_defaults[_ErrorHandler]=function(err){};function execute_preloaded_script(chain_opts,script_obj,registry_item){var script;function preload_execute_finished(){if(script!=null){script=null;script_executed(registry_item)}}if(registry[script_obj.src].finished)return;if(!chain_opts[_AllowDuplicates])registry[script_obj.src].finished=true;script=registry_item.elem||document.createElement("script");if(script_obj.type)script.type=script_obj.type;if(script_obj.charset)script.charset=script_obj.charset;create_script_load_listener(script,registry_item,"finished",preload_execute_finished);if(registry_item.elem){registry_item.elem=null}else if(registry_item.text){script.onload=script.onreadystatechange=null;script.text=registry_item.text}else{script.src=script_obj.real_src}append_to.insertBefore(script,append_to.firstChild);if(registry_item.text){preload_execute_finished()}}function do_script(chain_opts,script_obj,chain_group,preload_this_script){var registry_item,registry_items,ready_cb=function(){script_obj.ready_cb(script_obj,function(){execute_preloaded_script(chain_opts,script_obj,registry_item)})},finished_cb=function(){script_obj.finished_cb(script_obj,chain_group)};script_obj.src=canonical_uri(script_obj.src,chain_opts[_BasePath]);script_obj.real_src=script_obj.src+(chain_opts[_CacheBust]?((/\?.*$/.test(script_obj.src)?"&_":"?_")+~~(Math.random()*1E9)+"="):"");if(!registry[script_obj.src])registry[script_obj.src]={items:[],finished:false};registry_items=registry[script_obj.src].items;if(chain_opts[_AllowDuplicates]||registry_items.length==0){registry_item=registry_items[registry_items.length]={ready:false,finished:false,ready_listeners:[ready_cb],finished_listeners:[finished_cb]};request_script(chain_opts,script_obj,registry_item,((preload_this_script)?function(){registry_item.ready=true;for(var i=0;i<registry_item.ready_listeners.length;i++){registry_item.ready_listeners[i]()}registry_item.ready_listeners=[]}:function(){script_executed(registry_item)}),preload_this_script)}else{registry_item=registry_items[0];if(registry_item.finished){finished_cb()}else{registry_item.finished_listeners.push(finished_cb)}}}function create_chain(){var chainedAPI,chain_opts=merge_objs(global_defaults,{}),chain=[],exec_cursor=0,scripts_currently_loading=false,group;function chain_script_ready(script_obj,exec_trigger){if(chain_opts[_Debug])log_msg("script preload finished: "+script_obj.real_src);script_obj.ready=true;script_obj.exec_trigger=exec_trigger;advance_exec_cursor()}function chain_script_executed(script_obj,chain_group){if(chain_opts[_Debug])log_msg("script execution finished: "+script_obj.real_src);script_obj.ready=script_obj.finished=true;script_obj.exec_trigger=null;for(var i=0;i<chain_group.scripts.length;i++){if(!chain_group.scripts[i].finished)return}chain_group.finished=true;advance_exec_cursor()}function advance_exec_cursor(){while(exec_cursor<chain.length){if(is_func(chain[exec_cursor])){if(chain_opts[_Debug])log_msg("$LAB.wait() executing: "+chain[exec_cursor]);try{chain[exec_cursor++]()}catch(err){chain_opts[_ErrorHandler](err);if(chain_opts[_Debug])log_error("$LAB.wait() error caught: ",err)}continue}else if(!chain[exec_cursor].finished){if(check_chain_group_scripts_ready(chain[exec_cursor]))continue;break}exec_cursor++}if(exec_cursor==chain.length){scripts_currently_loading=false;group=false}}function init_script_chain_group(){if(!group||!group.scripts){chain.push(group={scripts:[],finished:true})}}chainedAPI={script:function(){for(var i=0;i<arguments.length;i++){(function(script_obj,script_list){var splice_args;if(!is_array(script_obj)){script_list=[script_obj]}for(var j=0;j<script_list.length;j++){init_script_chain_group();script_obj=script_list[j];if(is_func(script_obj))script_obj=script_obj();if(!script_obj)continue;if(is_array(script_obj)){splice_args=[].slice.call(script_obj);splice_args.unshift(j,1);[].splice.apply(script_list,splice_args);j--;continue}if(typeof script_obj=="string")script_obj={src:script_obj};script_obj=merge_objs(script_obj,{ready:false,ready_cb:chain_script_ready,finished:false,finished_cb:chain_script_executed});group.finished=false;group.scripts.push(script_obj);do_script(chain_opts,script_obj,group,(can_use_preloading&&scripts_currently_loading));scripts_currently_loading=true;if(chain_opts[_AlwaysPreserveOrder])chainedAPI.wait()}})(arguments[i],arguments[i])}return chainedAPI},wait:function(){if(arguments.length>0){for(var i=0;i<arguments.length;i++){chain.push(arguments[i])}group=chain[chain.length-1]}else group=false;advance_exec_cursor();return chainedAPI}};return{script:chainedAPI.script,wait:chainedAPI.wait,setOptions:function(opts){merge_objs(opts,chain_opts);return chainedAPI}}}instanceAPI={setGlobalDefaults:function(opts){merge_objs(opts,global_defaults);return instanceAPI},setOptions:function(){return create_chain().setOptions.apply(null,arguments)},script:function(){return create_chain().script.apply(null,arguments)},wait:function(){return create_chain().wait.apply(null,arguments)},queueScript:function(){queue[queue.length]={type:"script",args:[].slice.call(arguments)};return instanceAPI},queueWait:function(){queue[queue.length]={type:"wait",args:[].slice.call(arguments)};return instanceAPI},runQueue:function(){var $L=instanceAPI,len=queue.length,i=len,val;for(;--i>=0;){val=queue.shift();$L=$L[val.type].apply(null,val.args)}return $L},noConflict:function(){global.$LAB=_$LAB;return instanceAPI},sandbox:function(){return create_sandbox()}};return instanceAPI}global.$LAB=create_sandbox();(function(addEvent,domLoaded,handler){if(document.readyState==null&&document[addEvent]){document.readyState="loading";document[addEvent](domLoaded,handler=function(){document.removeEventListener(domLoaded,handler,false);document.readyState="complete"},false)}})("addEventListener","DOMContentLoaded")})(this);