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if(n!==0&&Math.abs(n)<0.000001){return n.toExponential(3);} return FMT?FMT.format(n):String(n); } function parseNum(raw){ var s=String(raw).replace(/[\s\u00a0]/g,''); if(s.charAt(s.length-1)==='%'){s=s.slice(0,-1);} if(s===''){return {empty:true};} var hasComma=s.indexOf(',')!==-1,hasDot=s.indexOf('.')!==-1; if(hasComma&&hasDot){ if(s.lastIndexOf(',')>s.lastIndexOf('.')){s=s.replace(/\./g,'').replace(',','.');} else{s=s.replace(/,/g,'');} }else if(hasComma){ if(/^[+-]?\d{1,3}(,\d{3})+$/.test(s)){s=s.replace(/,/g,'');} else{s=s.replace(',','.');} } if(!/^[+-]?(\d+\.?\d*|\.\d+)$/.test(s)){return {invalid:true};} var n=Number(s); if(!isFinite(n)){return {invalid:true};} return {value:n}; } var MINUS=' \u2212 ',TIMES=' \u00d7 ',DIV=' \u00f7 '; var CALCS={ percentOf:function(x,y){ var r=x/100*y; return {num:r,main:fmt(r),detail:fmt(x)+'% of '+fmt(y)+' = '+fmt(x)+DIV+'100'+TIMES+fmt(y)+' = '+fmt(r)}; }, whatPercent:function(x,y){ if(y===0){return {error:'Y cannot be zero, because dividing by zero is not possible.'};} var r=x/y*100; return {num:r,main:fmt(r)+'%',detail:fmt(x)+' is '+fmt(r)+'% of '+fmt(y)+'. Formula: '+fmt(x)+DIV+fmt(y)+TIMES+'100 = '+fmt(r)+'%'}; }, change:function(x,y){ if(x===0){return {error:'X (the starting value) cannot be zero, because a percentage change from zero is undefined.'};} var r=(y-x)/Math.abs(x)*100; var rc=clean(r); var word=rc>0?'an increase of ':'a decrease of '; var formula='Formula: ('+fmt(y)+MINUS+fmt(x)+')'+DIV+fmt(Math.abs(x))+TIMES+'100 = '+fmt(r)+'%'; if(rc===0){return {num:r,main:'0%',detail:'No change from '+fmt(x)+' to '+fmt(y)+'. '+formula};} return {num:r,main:(rc>0?'+':'')+fmt(r)+'%',detail:'From '+fmt(x)+' to '+fmt(y)+' is '+word+fmt(Math.abs(r))+'%. '+formula}; }, addSub:function(x,y,mode){ var amount=x*y/100; var sub=(mode==='subtract'); var r=sub?x-amount:x+amount; return {num:r,main:fmt(r),detail:fmt(x)+(sub?MINUS:' + ')+fmt(y)+'% = '+fmt(x)+(sub?MINUS:' + ')+fmt(amount)+' = '+fmt(r)}; }, ofWhat:function(x,y){ if(y===0){return {error:'Y (the percentage) cannot be zero, because dividing by zero is not possible.'};} var r=x/(y/100); return {num:r,main:fmt(r),detail:fmt(x)+' is '+fmt(y)+'% of '+fmt(r)+'. Formula: '+fmt(x)+DIV+'('+fmt(y)+DIV+'100) = '+fmt(r)} } }; function fallbackCopy(str,done){ var ta=document.createElement('textarea'); ta.value=str;ta.setAttribute('readonly',''); ta.style.position='fixed';ta.style.top='-1000px';ta.style.opacity='0'; root.appendChild(ta);ta.select(); try{ta.setSelectionRange(0,str.length);}catch(e){} var ok=false; try{ok=document.execCommand('copy');}catch(e){ok=false;} root.removeChild(ta); done(ok); } function copyText(str,done){ if(navigator.clipboard){ if(window.isSecureContext){ navigator.clipboard.writeText(str).then(function(){done(true);},function(){fallbackCopy(str,done);}); return; } } fallbackCopy(str,done); } function setupCard(card){ var name=card.getAttribute('data-calc'); var inputs=Array.prototype.slice.call(card.querySelectorAll('input[data-field]')); var sel=card.querySelector('select[data-field]'); var out=card.querySelector('.fl-pc__out'); var mainEl=card.querySelector('[data-main]'); var detailEl=card.querySelector('[data-detail]'); var btnCopy=card.querySelector('[data-act="copy"]'); var btnClear=card.querySelector('[data-act="clear"]'); var msgEl=card.querySelector('[data-msg]'); if(!CALCS[name]||!out||!mainEl||!detailEl||!btnCopy||!btnClear||inputs.length<2){throw new Error('a calculator card is incomplete');} var copyValue='',timer,msgTimer; function show(state,main,detail,copy){ out.className='fl-pc__out'+(state?' is-'+state:''); mainEl.textContent=main; detailEl.textContent=detail; copyValue=copy; btnCopy.disabled=!copy; } function update(){ var vals={},anyEmpty=false,bad=null; inputs.forEach(function(inp){ inp.removeAttribute('aria-invalid'); var p=parseNum(inp.value); if(p.empty){anyEmpty=true;return;} if(p.invalid){ inp.setAttribute('aria-invalid','true'); if(!bad){bad=inp;} return; } vals[inp.getAttribute('data-field')]=p.value; }); if(bad){ show('error','','Please enter a valid number in the "'+bad.getAttribute('data-name')+'" box. Use digits with an optional minus sign and decimal point.',''); return; } if(anyEmpty){ show('','','Enter both numbers to see the result.',''); return; } var r; try{r=CALCS[name](vals.x,vals.y,sel?sel.value:'');}catch(e){r={error:'Sorry, this could not be calculated.'};} if(r.error){show('error','',r.error,'');return;} if(!isFinite(r.num)){show('error','','The result is too large to display.','');return;} show('ok',r.main,r.detail,r.main); } inputs.forEach(function(inp){ inp.addEventListener('input',function(){clearTimeout(timer);timer=setTimeout(update,250);}); }); if(sel){sel.addEventListener('change',update);} btnCopy.addEventListener('click',function(){ if(!copyValue){return;} copyText(copyValue,function(ok){ msgEl.textContent=ok?'Copied.':'Copy failed. Please copy it manually.'; msgEl.style.color=ok?'':'#b91c1c'; clearTimeout(msgTimer); msgTimer=setTimeout(function(){msgEl.textContent='';},2500); }); }); btnClear.addEventListener('click',function(){ clearTimeout(timer); inputs.forEach(function(inp){inp.value='';}); update(); inputs[0].focus(); }); update(); } cardEls.forEach(setupCard); if(loadingEl){loadingEl.hidden=true;} } function init(root){ if(root.getAttribute('data-init')==='1'){return;} root.setAttribute('data-init','1'); var loadingEl=root.querySelector('#fl-pc-loading'); try{ build(root,loadingEl); }catch(err){ if(loadingEl){ loadingEl.hidden=false; loadingEl.textContent='Sorry, this calculator could not start ('+(err&&err.message?err.message:'unknown error')+'). Please reload the page.'; } } } function start(){ var root=document.getElementById('fl-pc'); if(!root){return false;} init(root); return true; } if(!start()){ var tries=0; var tmr=setInterval(function(){ tries=tries+1; if(start()||tries>=50){clearInterval(tmr);} },200); document.addEventListener('DOMContentLoaded',start); } })();