JS1k: The JavaScript code golfing competition

a="\",[.@functiI A(b,a){while(x||c]!=bc>Oc+aPx+G=a?cQ:cP=a?C:B)||G==b-1}z=document.body,T=cle,S=Uring.fromCh;zVinnerHTML<pWu>Reseep	 <u>Uop	\\nUaZ:  Ueps: \\n` Data`<~ea_~eaq_qq_q_pW>@v=z[vchildWn[0][va0avalueHi JS1K!@f2f]+,[.[-],]@g3EIcliZ!(b=cP?F():gVLsubstr(0,c)+\"<u #=baZground:Wd>\"+b+\"	\"+L](c+1gN,R=|=xO>d<Qd+-Q.(jV]+=S(R)+(k%80?\"\":\"\\n),(=n.chAt(0)|0,11(n=n[L](1))||\" ;b=B[&!RA(C,0,cb=C]RA(B,1,Qcc,7b,9S(s[8d&=32767]&=2554]s.join(5o};(f[$Ikeyup=a[$lO]T(l);s=[Y=o=c=d=kOn=am=fF((j4PV]})(3FY2]f[K#[Xdisplay=aY?NbloZ\":M;g11]Y?MnIe\":N;Y?T(l):l=set(E,1)})(Y=1)});";for(b in c="~text
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

//function A(){x=0;while(((x|=0)||m[c]!=']')&&m[c+1])x+=(G=m[c++])=='['||G==']'&&-1}function B(){x=0;while(((x|=0)||m[c]!='[')&&m[c-1])x+=(G=m[c--])==']'||G=='['&&-1}
//function A(_,I){x=0;while(((x|=0)||m[c]!=(I?'[':']'))&&m[c+(I?-1:1)])x+=(G=m[(I?c--:c++)])==(I?']':'[')||G==(I?'[':']')&&-1}function B(){A(0,1)}
',[.';
function A(I,J){//J=0:jump back, J=1:jump forward,I=(J?B:C)
	while(x||m[c]!=I&&c>=0&&m[c+J])
//		g[Z]=m[L='substr'](0,c)+'<u style="background:#ccc;">'+b+'</u>'+m[L](c+1), // update position in while
//		v[4][Q] = x+" "+c+" "+I+" "+J+" "+(c>=J|m[c+J])+" ", // debug in stack output
				x+=(G=m[J?c--:c++])==(J?C:B)||G==I&&-1
}

/*
m[c+(Y?-1:1)]
Y?c>=0:m[c+1]
c>=Y|m[c+Y]
*/
//function E(){H(f,M);H(g,N);H(a,M);H(e,O);l=setInterval(D,5)}function F(){H(f,N);H(g,M);H(a,O);H(e,M);T(l)}
//function E(_,I){H(f,I?N:M);H(g,I?M:N);H(a,I?O:M);H(e,I?M:O);I?T(l):l=setInterval(D,5)}function F(){E(0,1)}
//function E(){H(f,Y?N:M);H(g,Y?M:N);H(a,Y?O:M);H(v[11],Y?M:O);Y?T(l):l=setInterval(D,5)}function F(){Y=E(Y=1)}

z=document.body,T=clearInterval,S=String.fromCharCode;
z[Z='innerHTML']='<pre><u>Reset</u> <u>Step</u> <u>Start</u> <u>Stop</u>\nStack: <input> Steps: <b></b>\nCode[<b></b>]=<b></b> Data[<b></b>]=<b></b><input><b></b><textarea></textarea><q></q><q></q></pre>';
v=z[v='children'][0][v];

a=v[10]; // input input
a[Q='value']='Hi JS1K!';

f=v[12]; // source
f[Q]='+><,[.[-],]';
//f[Q]='++++++++++[>+++++++>++++++++++>+++>+<<<<-]>++.>+.+++++++..+++.>++.<<+++++++++++++++.>.+++.------.--------.>+.>.[,.]';

g=v[13]; // input locator

E=v[1][z='onclick']=
				// step
				function(){
					!(b=m[c])?F():
						// g[Z]=m,
						g[Z]=m[L='substr'](0,c)+'<u style=background:red>'+b+'</u>'+m[L](c+1),
						
						g[K][X]=N, // show source position when stepping
						R=s[d]|=x=0,
						b=='>'&&++d,
						b=='<'&&--d,
						b=='+'&&++s[d],
						b=='-'&&--s[d],
						//b=='-'&&(s[d]=0),
						b=='.'&&(j[Z]+=S(R)+(++k%80?'':'\n')), // output
						//b==','&&(n?((s[d]=n.charCodeAt(0)),n=n[L](1)):s[d]=0),
						b==','&&(s[d]=n.charCodeAt(0)|0,v[11][Z]=(n=n[L](1))||' ') // input
						b==(B='[')&!R&&A(C,0,++c),
						b==(C=']')&&R&&A(B,1,--c),
					
						++c,
						v[7][Z]=b, // code (increase after last usage)
						v[9][Z]=S(s[v[8][Z]=d&=32767]&=255), // data
						v[4][Q]=s.join(), // stack
						v[5][Z]=++o // steps
				};

// reset function (also an event when editing input/source and pressing the R link)
(f[$='onkeyup']=a[$]=v[l=0][z]=function(){
	T(l);
	s=[Y=o=c=d=k=0];
	n=a[Q];
	m=f[Q];
	F((j=v[14])[Z]='')
	//i=-1;while((i+=80)<m.length)m=m[L](0,i)+'\n'+m[L](i);
})( // reset is immediately invoked
// start and stop (E) func defs and event hooking (as the call arguments for invoking reset, note that they execute first, then the reset, which is no problem)
		v[3][z]=F=function(){Y=(v[2][z]=function(){
			//function H(I,J){I[K].display=J}H(f,Y?N:M);H(g,Y?M:N);H(a,Y?O:M);H(v[11],Y?M:O);
			f[K='style'][X='display']=a[K][X]=Y?N='block':M;
			g[K][X]=v[11][K][X]=Y?M='none':N;
		
			Y?T(l):l=setInterval(E,1)
		})(Y=1)}
)