/**
 * ToolsOfIndia.com — Tool Engine v4 (te.js)
 * Complete calculator logic for all tools + generic fallback
 * Exposes window.ToolEngine
 */
(function() {
'use strict';

// ─── Number formatting helpers ──────────────────────────────────────────────

function fi(n) {
  if (n === null || n === undefined || isNaN(n)) return '0';
  var neg = n < 0, abs = Math.abs(n).toFixed(2), p = abs.split('.');
  var i = p[0], l3 = i.slice(-3), r = i.slice(0, -3);
  if (r) i = r.replace(/\B(?=(\d{2})+(?!\d))/g, ',') + ',' + l3;
  return (neg ? '-Rs ' : 'Rs ') + i + '.' + p[1];
}

function fn(n) {
  if (!n && n !== 0) return '0';
  return Math.round(n).toString().replace(/\B(?=(\d{3})+(?!\d))/g, ',');
}

function fp(n) { return Number(n).toFixed(2) + '%'; }

// ─── Generic / fallback calculator ──────────────────────────────────────────

/**
 * renderTool — unified dispatcher.
 * If a specific calculator exists for the slug, use it.
 * Otherwise render a simple generic calculator (Enter Value → Calculate).
 */
function renderTool(slug, container) {
  if (tools[slug]) {
    tools[slug].render(container);
    return;
  }
  // Generic fallback: Enter Value → Calculate → Show formatted result
  var id = slug.replace(/[^a-z0-9-]/g, '');
  container.innerHTML =
    '<div class="form-group"><label>Enter Value</label>'
    + '<input type="number" id="g-' + id + '-in" class="form-input" value="0" step="any"></div>'
    + '<button class="btn btn-primary btn-block" id="g-' + id + '-btn">Calculate</button>'
    + '<div class="result-box" id="g-' + id + '-res" style="display:none"></div>';
  document.getElementById('g-' + id + '-btn').onclick = function() {
    var v = parseFloat(document.getElementById('g-' + id + '-in').value) || 0;
    var r = document.getElementById('g-' + id + '-res');
    r.style.display = 'block';
    r.innerHTML = '<div class="result-row"><span class="label">Value</span><span class="value success">'
      + fi(v) + '</span></div>';
  };
}

// ─── All tool calculators ───────────────────────────────────────────────────

var tools = {
  'gst-calculator': {
    render: function(c) {
      c.innerHTML = '<div class="form-group"><label>Amount</label><input type="number" id="gst-amt" class="form-input" value="10000"></div>'
        + '<div class="form-group"><label>GST Rate</label><div class="toggle-group" id="gst-rate">'
        + ['5','12','18','28'].map(function(v){return '<label class="toggle-label"><input type="radio" name="gst" value="'+v+'"'+(v==='18'?' checked':'')+'> '+v+'%</label>';}).join('')
        + '</div></div>'
        + '<div class="form-group"><label>Type</label><div class="toggle-group">'
        + '<label class="toggle-label"><input type="radio" name="gst-type" value="excl" checked> Exclusive (Add GST)</label>'
        + '<label class="toggle-label"><input type="radio" name="gst-type" value="incl"> Inclusive (Remove GST)</label>'
        + '</div></div>'
        + '<button class="btn btn-primary btn-block" id="gst-btn">Calculate GST</button>'
        + '<div class="result-box" id="gst-res" style="display:none"></div>';
      document.getElementById('gst-btn').onclick = function() {
        var amt = parseFloat(document.getElementById('gst-amt').value) || 0;
        var rate = parseFloat(document.querySelector('input[name="gst"]:checked').value) || 18;
        var type = document.querySelector('input[name="gst-type"]:checked').value;
        var gst, net, total;
        if (type === 'excl') {
          net = amt; gst = amt * rate / 100; total = amt + gst;
        } else {
          total = amt; gst = amt * rate / (100 + rate); net = amt - gst;
        }
        var r = document.getElementById('gst-res');
        r.style.display = 'block';
        r.innerHTML = '<div class="result-row"><span class="label">Net Amount</span><span class="value">'+fi(net)+'</span></div>'
          + '<div class="result-row"><span class="label">GST ('+rate+'%)</span><span class="value primary">'+fi(gst)+'</span></div>'
          + '<div class="result-row"><span class="label">CGST (half)</span><span class="value">'+fi(gst/2)+'</span></div>'
          + '<div class="result-row"><span class="label">SGST (half)</span><span class="value">'+fi(gst/2)+'</span></div>'
          + '<div class="result-row" style="border-top:2px solid #e5e7eb;padding-top:12px;margin-top:8px"><span class="label"><strong>Total</strong></span><span class="value success"><strong>'+fi(total)+'</strong></span></div>';
      };
    }
  },

  'tds-calculator': {
    render: function(c) {
      c.innerHTML = '<div class="form-group"><label>Annual Salary</label><input type="number" id="tds-sal" class="form-input" value="1200000"></div>'
        + '<div class="form-group"><label>Section 80C Deductions</label><input type="number" id="tds-80c" class="form-input" value="150000"></div>'
        + '<div class="form-group"><label>Section 80D (Health Insurance)</label><input type="number" id="tds-80d" class="form-input" value="25000"></div>'
        + '<button class="btn btn-primary btn-block" id="tds-btn">Calculate TDS</button>'
        + '<div class="result-box" id="tds-res" style="display:none"></div>';
      document.getElementById('tds-btn').onclick = function() {
        var sal = parseFloat(document.getElementById('tds-sal').value) || 0;
        var d80c = Math.min(parseFloat(document.getElementById('tds-80c').value) || 0, 150000);
        var d80d = Math.min(parseFloat(document.getElementById('tds-80d').value) || 0, 25000);
        var taxable = Math.max(0, sal - 50000 - d80c - d80d);
        var tax = 0;
        if (taxable > 10000000) tax = (taxable - 10000000) * 0.30 + 112500;
        else if (taxable > 5000000) tax = (taxable - 5000000) * 0.20 + 12500;
        else if (taxable > 250000) tax = (taxable - 250000) * 0.05;
        var cess = tax * 0.04;
        var total = tax + cess;
        document.getElementById('tds-res').style.display = 'block';
        document.getElementById('tds-res').innerHTML = '<div class="result-row"><span class="label">Gross Salary</span><span class="value">'+fi(sal)+'</span></div>'
          + '<div class="result-row"><span class="label">Standard Deduction</span><span class="value">'+fi(50000)+'</span></div>'
          + '<div class="result-row"><span class="label">Total Deductions</span><span class="value">'+fi(d80c+d80d)+'</span></div>'
          + '<div class="result-row"><span class="label">Taxable Income</span><span class="value">'+fi(taxable)+'</span></div>'
          + '<div class="result-row"><span class="label">Income Tax</span><span class="value primary">'+fi(tax)+'</span></div>'
          + '<div class="result-row"><span class="label">Health & Edu Cess (4%)</span><span class="value">'+fi(cess)+'</span></div>'
          + '<div class="result-row" style="border-top:2px solid #111;padding-top:12px"><span class="label"><strong>Total TDS</strong></span><span class="value success"><strong>'+fi(total)+'</strong></span></div>'
          + '<div class="result-row"><span class="label">Monthly TDS</span><span class="value">'+fi(total/12)+'</span></div>';
      };
    }
  },

  'sip-calculator': {
    render: function(c) {
      c.innerHTML = '<div class="form-group"><label>Monthly Investment (Rs)</label><input type="range" id="sip-amt" min="100" max="100000" value="5000" step="100"><div style="display:flex;justify-content:space-between"><span>100</span><span class="range-value" id="sip-amt-v">5,000</span><span>1,00,000</span></div></div>'
        + '<div class="form-group"><label>Expected Return (%)</label><input type="range" id="sip-ret" min="1" max="30" value="12" step="0.5"><div style="display:flex;justify-content:space-between"><span>1%</span><span class="range-value" id="sip-ret-v">12%</span><span>30%</span></div></div>'
        + '<div class="form-group"><label>Years</label><input type="range" id="sip-yr" min="1" max="40" value="10" step="1"><div style="display:flex;justify-content:space-between"><span>1</span><span class="range-value" id="sip-yr-v">10</span><span>40</span></div></div>'
        + '<button class="btn btn-primary btn-block" id="sip-btn">Calculate SIP</button>'
        + '<div class="result-box" id="sip-res" style="display:none"></div>';
      ['amt','ret','yr'].forEach(function(k){
        document.getElementById('sip-'+k).oninput = function(){
          var v = this.value;
          if(k==='amt') document.getElementById('sip-amt-v').textContent = Number(v).toLocaleString('en-IN');
          else document.getElementById('sip-'+k+'-v').textContent = v + (k==='yr'?' yrs':'%');
        };
      });
      document.getElementById('sip-btn').onclick = function() {
        var m = parseFloat(document.getElementById('sip-amt').value) || 0;
        var r = (parseFloat(document.getElementById('sip-ret').value) || 0) / 12 / 100;
        var y = parseInt(document.getElementById('sip-yr').value) || 0;
        var c = 0, ti = 0;
        for(var i=0; i<y*12; i++) { c = c * (1 + r) + m; ti += m; }
        var ret = c - ti;
        document.getElementById('sip-res').style.display = 'block';
        document.getElementById('sip-res').innerHTML = '<div class="result-row"><span>Total Invested</span><span class="value">'+fi(ti)+'</span></div>'
          + '<div class="result-row"><span>Expected Amount</span><span class="value success">'+fi(c)+'</span></div>'
          + '<div class="result-row"><span>Total Returns</span><span class="value primary">'+fi(ret)+'</span></div>';
      };
    }
  },

  'emi-calculator': {
    render: function(c) {
      c.innerHTML = '<div class="form-group"><label>Loan Amount (Rs)</label><input type="range" id="emi-p" min="10000" max="10000000" value="5000000" step="10000"><div style="display:flex;justify-content:space-between"><span>10K</span><span class="range-value" id="emi-p-v">50,00,000</span><span>1Cr</span></div></div>'
        + '<div class="form-group"><label>Interest Rate (%)</label><input type="range" id="emi-r" min="1" max="25" value="8.5" step="0.1"><div style="display:flex;justify-content:space-between"><span>1%</span><span class="range-value" id="emi-r-v">8.5%</span><span>25%</span></div></div>'
        + '<div class="form-group"><label>Years</label><input type="range" id="emi-n" min="1" max="40" value="20" step="1"><div style="display:flex;justify-content:space-between"><span>1</span><span class="range-value" id="emi-n-v">20</span><span>40</span></div></div>'
        + '<button class="btn btn-primary btn-block" id="emi-btn">Calculate EMI</button>'
        + '<div class="result-box" id="emi-res" style="display:none"></div>';
      ['p','r','n'].forEach(function(k){
        document.getElementById('emi-'+k).oninput = function(){
          var v = this.value;
          var el = document.getElementById('emi-'+k+'-v');
          if(k==='p') el.textContent = Number(v).toLocaleString('en-IN');
          else if(k==='r') el.textContent = v+'%';
          else el.textContent = v;
        };
      });
      document.getElementById('emi-btn').onclick = function() {
        var P = parseFloat(document.getElementById('emi-p').value) || 0;
        var ar = parseFloat(document.getElementById('emi-r').value) || 0;
        var N = (parseInt(document.getElementById('emi-n').value) || 1) * 12;
        var mr = ar / 12 / 100;
        var emi = P * mr * Math.pow(1+mr,N) / (Math.pow(1+mr,N)-1);
        if(ar===0) emi = P/N;
        var tp = emi * N, ti = tp - P;
        document.getElementById('emi-res').style.display = 'block';
        document.getElementById('emi-res').innerHTML = '<div class="result-amount">'+fi(emi)+'/month</div>'
          + '<div style="text-align:center;font-size:13px;color:#6b7280;margin-bottom:12px">Monthly EMI</div>'
          + '<div class="result-row"><span>Loan Amount</span><span>'+fi(P)+'</span></div>'
          + '<div class="result-row"><span>Total Interest</span><span class="value primary">'+fi(ti)+'</span></div>'
          + '<div class="result-row"><span>Total Payment</span><span class="value success">'+fi(tp)+'</span></div>';
      };
    }
  },

  'salary-calculator': {
    render: function(c) {
      c.innerHTML = '<div class="form-group"><label>Annual CTC (Rs)</label><input type="range" id="sal-ctc" min="120000" max="5000000" value="1200000" step="10000"><div style="display:flex;justify-content:space-between"><span>1.2L</span><span class="range-value" id="sal-ctc-v">12,00,000</span><span>50L</span></div></div>'
        + '<div class="form-group"><label>Basic (% of CTC)</label><input type="range" id="sal-basic" min="30" max="60" value="40" step="5"><div style="display:flex;justify-content:space-between"><span>30%</span><span class="range-value" id="sal-basic-v">40%</span><span>60%</span></div></div>'
        + '<button class="btn btn-primary btn-block" id="sal-btn">Calculate Salary</button>'
        + '<div class="result-box" id="sal-res" style="display:none"></div>';
      document.getElementById('sal-ctc').oninput = function(){ document.getElementById('sal-ctc-v').textContent = Number(this.value).toLocaleString('en-IN'); };
      document.getElementById('sal-basic').oninput = function(){ document.getElementById('sal-basic-v').textContent = this.value+'%'; };
      document.getElementById('sal-btn').onclick = function() {
        var ctc = parseFloat(document.getElementById('sal-ctc').value) || 0;
        var bp = (parseFloat(document.getElementById('sal-basic').value) || 40) / 100;
        var basic = ctc * bp;
        var hra = basic * 0.5;
        var pf = Math.min(basic * 0.12, 1500*12);
        var gratuity = basic * 0.0481;
        var profTax = ctc > 600000 ? 2500 : 1800;
        var taxable = ctc - 50000 - pf;
        var tax = 0;
        if(taxable > 500000) tax = (taxable-500000)*0.20 + 12500;
        else if(taxable > 250000) tax = (taxable-250000)*0.05;
        tax = tax * 1.04;
        var ded = pf + profTax + tax;
        var inhand = (ctc - ded) / 12;
        document.getElementById('sal-res').style.display = 'block';
        document.getElementById('sal-res').innerHTML = '<div class="result-amount">'+fi(inhand)+'/month</div>'
          + '<div style="text-align:center;font-size:13px;color:#6b7280;margin-bottom:12px">Monthly In-Hand</div>'
          + '<div class="result-row"><span>CTC</span><span>'+fi(ctc)+'</span></div>'
          + '<div class="result-row"><span>Basic</span><span>'+fi(basic)+'</span></div>'
          + '<div class="result-row"><span>HRA</span><span>'+fi(hra)+'</span></div>'
          + '<div class="result-row"><span>PF</span><span class="value primary">'+fi(pf)+'</span></div>'
          + '<div class="result-row"><span>Gratuity</span><span>'+fi(gratuity)+'</span></div>'
          + '<div class="result-row"><span>Professional Tax</span><span class="value primary">'+fi(profTax)+'</span></div>'
          + '<div class="result-row"><span>Income Tax</span><span class="value primary">'+fi(tax)+'</span></div>'
          + '<div class="result-row" style="border-top:2px solid #111;padding-top:12px"><span><strong>Annual In-Hand</strong></span><span class="value success"><strong>'+fi(ctc-ded)+'</strong></span></div>';
      };
    }
  },

  'ppf-calculator': {
    render: function(c) {
      c.innerHTML = '<div class="form-group"><label>Yearly Investment (Rs)</label><input type="range" id="ppf-amt" min="500" max="150000" value="50000" step="500"><div style="display:flex;justify-content:space-between"><span>500</span><span class="range-value" id="ppf-amt-v">50,000</span><span>1.5L</span></div></div>'
        + '<div class="form-group"><label>Years (15-30)</label><input type="range" id="ppf-yr" min="15" max="30" value="15" step="1"><div style="display:flex;justify-content:space-between"><span>15</span><span class="range-value" id="ppf-yr-v">15</span><span>30</span></div></div>'
        + '<button class="btn btn-primary btn-block" id="ppf-btn">Calculate PPF</button>'
        + '<div class="result-box" id="ppf-res" style="display:none"></div>';
      document.getElementById('ppf-amt').oninput = function(){ document.getElementById('ppf-amt-v').textContent = Number(this.value).toLocaleString('en-IN'); };
      document.getElementById('ppf-yr').oninput = function(){ document.getElementById('ppf-yr-v').textContent = this.value; };
      document.getElementById('ppf-btn').onclick = function() {
        var yr = parseInt(document.getElementById('ppf-yr').value) || 15;
        var amt = parseFloat(document.getElementById('ppf-amt').value) || 0;
        var rate = 0.071, total = 0, corpus = 0;
        for(var y=0; y<yr; y++) { total += amt; corpus = (corpus + amt) * (1 + rate); }
        document.getElementById('ppf-res').style.display = 'block';
        document.getElementById('ppf-res').innerHTML = '<div class="result-row"><span>Total Invested</span><span>'+fi(total)+'</span></div>'
          + '<div class="result-row"><span>Maturity Amount</span><span class="value success">'+fi(corpus)+'</span></div>'
          + '<div class="result-row"><span>Interest Earned</span><span class="value primary">'+fi(corpus-total)+'</span></div>';
      };
    }
  },

  'epf-calculator': {
    render: function(c) {
      c.innerHTML = '<div class="form-group"><label>Monthly Salary (Basic+DA)</label><input type="number" id="epf-sal" class="form-input" value="30000"></div>'
        + '<div class="form-group"><label>Years</label><input type="range" id="epf-yr" min="1" max="40" value="20" step="1"><div style="display:flex;justify-content:space-between"><span>1</span><span class="range-value" id="epf-yr-v">20</span><span>40</span></div></div>'
        + '<button class="btn btn-primary btn-block" id="epf-btn">Calculate EPF</button>'
        + '<div class="result-box" id="epf-res" style="display:none"></div>';
      document.getElementById('epf-yr').oninput = function(){ document.getElementById('epf-yr-v').textContent = this.value; };
      document.getElementById('epf-btn').onclick = function() {
        var sal = parseFloat(document.getElementById('epf-sal').value) || 0;
        var yr = parseInt(document.getElementById('epf-yr').value) || 20;
        var mr = 0.0815/12, ee = sal*0.12, er = sal*0.12, c=0, ti=0;
        for(var m=0; m<yr*12; m++) { c = c*(1+mr) + ee + er; ti += ee + er; }
        document.getElementById('epf-res').style.display = 'block';
        document.getElementById('epf-res').innerHTML = '<div class="result-row"><span>Total Contributions</span><span>'+fi(ti)+'</span></div>'
          + '<div class="result-row"><span>EPF Corpus</span><span class="value success">'+fi(c)+'</span></div>'
          + '<div class="result-row"><span>Interest Earned</span><span class="value primary">'+fi(c-ti)+'</span></div>';
      };
    }
  },

  'mutual-fund-calculator': {
    render: function(c) {
      c.innerHTML = '<div class="form-group"><label>Investment (Rs)</label><input type="range" id="mf-amt" min="1000" max="50000000" value="100000" step="1000"><div style="display:flex;justify-content:space-between"><span>1K</span><span class="range-value" id="mf-amt-v">1,00,000</span><span>5Cr</span></div></div>'
        + '<div class="form-group"><label>Expected Return (%)</label><input type="range" id="mf-ret" min="1" max="30" value="12" step="0.5"><div style="display:flex;justify-content:space-between"><span>1%</span><span class="range-value" id="mf-ret-v">12%</span><span>30%</span></div></div>'
        + '<div class="form-group"><label>Years</label><input type="range" id="mf-yr" min="1" max="40" value="10" step="1"><div style="display:flex;justify-content:space-between"><span>1</span><span class="range-value" id="mf-yr-v">10</span><span>40</span></div></div>'
        + '<button class="btn btn-primary btn-block" id="mf-btn">Calculate</button>'
        + '<div class="result-box" id="mf-res" style="display:none"></div>';
      ['amt','ret','yr'].forEach(function(k){
        document.getElementById('mf-'+k).oninput = function(){
          var v = this.value;
          if(k==='amt') document.getElementById('mf-amt-v').textContent = Number(v).toLocaleString('en-IN');
          else document.getElementById('mf-'+k+'-v').textContent = v + (k==='yr'?' yrs':'%');
        };
      });
      document.getElementById('mf-btn').onclick = function() {
        var p = parseFloat(document.getElementById('mf-amt').value) || 0;
        var r = (parseFloat(document.getElementById('mf-ret').value) || 0) / 100;
        var y = parseInt(document.getElementById('mf-yr').value) || 0;
        var a = p * Math.pow(1+r, y);
        document.getElementById('mf-res').style.display = 'block';
        document.getElementById('mf-res').innerHTML = '<div class="result-row"><span>Invested Amount</span><span>'+fi(p)+'</span></div>'
          + '<div class="result-row"><span>Expected Amount</span><span class="value success">'+fi(a)+'</span></div>'
          + '<div class="result-row"><span>Total Returns</span><span class="value primary">'+fi(a-p)+'</span></div>'
          + '<div class="result-row"><span>CAGR</span><span class="value accent">'+fp(r*100)+'</span></div>';
      };
    }
  },

  'qr-generator': {
    render: function(c) {
      c.innerHTML = '<div class="form-group"><label>Text or URL</label><input type="text" id="qr-txt" class="form-input" value="https://toolsofindia.com"></div>'
        + '<button class="btn btn-primary btn-block" id="qr-btn">Generate QR</button>'
        + '<div class="result-box" id="qr-res" style="display:none;text-align:center"></div>';
      document.getElementById('qr-btn').onclick = function() {
        var txt = encodeURIComponent(document.getElementById('qr-txt').value || 'https://toolsofindia.com');
        var url = 'https://chart.googleapis.com/chart?cht=qr&chs=200x200&chl='+txt;
        document.getElementById('qr-res').style.display = 'block';
        document.getElementById('qr-res').innerHTML = '<img src="'+url+'" alt="QR Code" style="max-width:200px;border-radius:8px;border:1px solid #e5e7eb">';
      };
    }
  },

  'password-generator': {
    render: function(c) {
      c.innerHTML = '<div class="form-group"><label>Length: <span id="pw-len-v">12</span></label><input type="range" id="pw-len" min="4" max="64" value="12"></div>'
        + '<div class="toggle-group">'
        + '<label><input type="checkbox" id="pw-upper" checked> A-Z</label>'
        + '<label><input type="checkbox" id="pw-lower" checked> a-z</label>'
        + '<label><input type="checkbox" id="pw-num" checked> 0-9</label>'
        + '<label><input type="checkbox" id="pw-sym"> !@#$</label>'
        + '</div>'
        + '<button class="btn btn-primary btn-block" id="pw-btn">Generate Password</button>'
        + '<div class="result-box" id="pw-res" style="display:none;text-align:center"></div>';
      document.getElementById('pw-len').oninput = function(){ document.getElementById('pw-len-v').textContent = this.value; };
      document.getElementById('pw-btn').onclick = function() {
        var len = parseInt(document.getElementById('pw-len').value) || 12;
        var chars = '';
        if(document.getElementById('pw-upper').checked) chars += 'ABCDEFGHIJKLMNOPQRSTUVWXYZ';
        if(document.getElementById('pw-lower').checked) chars += 'abcdefghijklmnopqrstuvwxyz';
        if(document.getElementById('pw-num').checked) chars += '0123456789';
        if(document.getElementById('pw-sym').checked) chars += '!@#$%^&*()_+-=[]{}|;:,.<>?';
        if(!chars) chars = 'abcdefghijklmnopqrstuvwxyz';
        var pw = '';
        for(var i=0; i<len; i++) pw += chars.charAt(Math.floor(Math.random()*chars.length));
        var str = 0;
        if(/[A-Z]/.test(pw)) str += 26;
        if(/[a-z]/.test(pw)) str += 26;
        if(/[0-9]/.test(pw)) str += 10;
        if(/[^A-Za-z0-9]/.test(pw)) str += 32;
        var entropy = len * (Math.log(str) / Math.log(2));
        var color = entropy < 30 ? '#ef4444' : entropy < 55 ? '#f59e0b' : '#10b981';
        var label = entropy < 30 ? 'Weak' : entropy < 55 ? 'Medium' : 'Strong';
        document.getElementById('pw-res').style.display = 'block';
        document.getElementById('pw-res').innerHTML = '<div style="font-size:20px;font-family:monospace;padding:12px;background:#f3f4f6;border-radius:8px;word-break:break-all">'+pw+'</div>'
          + '<div style="margin-top:8px;height:8px;background:#e5e7eb;border-radius:4px;overflow:hidden"><div style="width:'+Math.min(100,entropy*2)+'%;height:100%;background:'+color+';border-radius:4px;transition:all 0.3s"></div></div>'
          + '<div style="margin-top:4px;font-size:13px;color:'+color+'">'+label+' ('+entropy.toFixed(0)+' bits)</div>';
      };
    }
  },

  'bmi-calculator': {
    render: function(c) {
      c.innerHTML = '<div class="form-group"><label>Height (cm)</label><input type="range" id="bmi-h" min="100" max="250" value="170" step="0.5"><div style="display:flex;justify-content:space-between"><span>100</span><span class="range-value" id="bmi-h-v">170</span><span>250</span></div></div>'
        + '<div class="form-group"><label>Weight (kg)</label><input type="range" id="bmi-w" min="20" max="200" value="70" step="0.5"><div style="display:flex;justify-content:space-between"><span>20</span><span class="range-value" id="bmi-w-v">70</span><span>200</span></div></div>'
        + '<button class="btn btn-primary btn-block" id="bmi-btn">Calculate BMI</button>'
        + '<div class="result-box" id="bmi-res" style="display:none"></div>';
      document.getElementById('bmi-h').oninput = function(){ document.getElementById('bmi-h-v').textContent = this.value; };
      document.getElementById('bmi-w').oninput = function(){ document.getElementById('bmi-w-v').textContent = this.value; };
      document.getElementById('bmi-btn').onclick = function() {
        var h = (parseFloat(document.getElementById('bmi-h').value) || 170) / 100;
        var w = parseFloat(document.getElementById('bmi-w').value) || 70;
        var bmi = w / (h * h);
        var cat = bmi < 18.5 ? 'Underweight' : bmi < 25 ? 'Normal' : bmi < 30 ? 'Overweight' : 'Obese';
        var col = bmi < 18.5 ? '#3b82f6' : bmi < 25 ? '#10b981' : bmi < 30 ? '#f59e0b' : '#ef4444';
        document.getElementById('bmi-res').style.display = 'block';
        document.getElementById('bmi-res').innerHTML = '<div class="result-amount" style="color:'+col+'">'+bmi.toFixed(1)+'</div>'
          + '<div style="text-align:center;font-size:18px;font-weight:600;color:'+col+'">'+cat+'</div>'
          + '<div style="margin-top:8px;text-align:center;font-size:13px;color:#6b7280">Ideal: '+(18.5*h*h).toFixed(1)+' - '+(24.9*h*h).toFixed(1)+' kg</div>';
      };
    }
  },

  'word-counter': {
    render: function(c) {
      c.innerHTML = '<div class="form-group"><textarea id="wc-txt" class="form-input" rows="6" placeholder="Type or paste text here..." style="font-size:14px"></textarea></div>'
        + '<div class="result-box" id="wc-res"></div>';
      document.getElementById('wc-txt').oninput = function() {
        var t = this.value;
        var words = t.trim() ? t.trim().split(/\s+/).length : 0;
        var chars = t.length;
        var charsNoSpace = t.replace(/\s/g,'').length;
        var sentences = t.split(/[.!?]+/).filter(function(s){return s.trim().length>0;}).length;
        var paras = t.split(/\n\s*\n/).filter(function(p){return p.trim().length>0;}).length;
        document.getElementById('wc-res').innerHTML = '<div style="display:grid;grid-template-columns:repeat(3,1fr);gap:12px;text-align:center">'
          + '<div><div style="font-size:24px;font-weight:700;color:#1a56db">'+words+'</div><div style="font-size:12px;color:#6b7280">Words</div></div>'
          + '<div><div style="font-size:24px;font-weight:700;color:#059669">'+chars+'</div><div style="font-size:12px;color:#6b7280">Characters</div></div>'
          + '<div><div style="font-size:24px;font-weight:700;color:#8b5cf6">'+sentences+'</div><div style="font-size:12px;color:#6b7280">Sentences</div></div>'
          + '<div><div style="font-size:24px;font-weight:700;color:#f59e0b">'+paras+'</div><div style="font-size:12px;color:#6b7280">Paragraphs</div></div>'
          + '<div><div style="font-size:24px;font-weight:700;color:#ec4899">'+charsNoSpace+'</div><div style="font-size:12px;color:#6b7280">Chars (no space)</div></div>'
          + '<div><div style="font-size:24px;font-weight:700;color:#6366f1">'+Math.ceil(words/200)+'</div><div style="font-size:12px;color:#6b7280">Read (min)</div></div>'
          + '</div>';
      };
    }
  },

  'age-calculator': {
    render: function(c) {
      var today = new Date();
      var defY = today.getFullYear()-25, defM = String(today.getMonth()+1).padStart(2,'0'), defD = String(today.getDate()).padStart(2,'0');
      c.innerHTML = '<div class="form-group"><label>Date of Birth</label><input type="date" id="age-dob" class="form-input" value="'+defY+'-'+defM+'-'+defD+'"></div>'
        + '<button class="btn btn-primary btn-block" id="age-btn">Calculate Age</button>'
        + '<div class="result-box" id="age-res" style="display:none"></div>';
      document.getElementById('age-btn').onclick = function() {
        var dob = new Date(document.getElementById('age-dob').value);
        if(isNaN(dob.getTime())) return;
        var now = new Date();
        var y = now.getFullYear() - dob.getFullYear();
        var m = now.getMonth() - dob.getMonth();
        var d = now.getDate() - dob.getDate();
        if(d < 0) { m--; d += new Date(now.getFullYear(), now.getMonth(), 0).getDate(); }
        if(m < 0) { y--; m += 12; }
        var totalD = Math.floor((now - dob) / (1000*60*60*24));
        document.getElementById('age-res').style.display = 'block';
        document.getElementById('age-res').innerHTML = '<div style="display:grid;grid-template-columns:repeat(3,1fr);gap:12px;text-align:center">'
          + '<div><div style="font-size:32px;font-weight:800;color:#1a56db">'+y+'</div><div>Years</div></div>'
          + '<div><div style="font-size:32px;font-weight:800;color:#059669">'+m+'</div><div>Months</div></div>'
          + '<div><div style="font-size:32px;font-weight:800;color:#8b5cf6">'+d+'</div><div>Days</div></div>'
          + '</div><div style="margin-top:12px;text-align:center;font-size:14px;color:#6b7280">You have been alive for '+fn(totalD)+' days</div>';
      };
    }
  },

  'case-converter': {
    render: function(c) {
      c.innerHTML = '<div class="form-group"><textarea id="cc-txt" class="form-input" rows="6" placeholder="Type text here..."></textarea></div>'
        + '<div class="btn-group" style="flex-wrap:wrap">'
        + '<button class="btn btn-secondary" onclick="document.getElementById(\'cc-txt\').value=document.getElementById(\'cc-txt\').value.toUpperCase()">UPPERCASE</button>'
        + '<button class="btn btn-secondary" onclick="document.getElementById(\'cc-txt\').value=document.getElementById(\'cc-txt\').value.toLowerCase()">lowercase</button>'
        + '<button class="btn btn-secondary" onclick="var t=document.getElementById(\'cc-txt\');t.value=t.value.replace(/\\w\\S*/g,function(w){return w.charAt(0).toUpperCase()+w.substr(1).toLowerCase();})">Title Case</button>'
        + '<button class="btn btn-secondary" onclick="var t=document.getElementById(\'cc-txt\');t.value=t.value.toLowerCase().replace(/(^\\s*\\w|[.!?]\\s*\\w)/g,function(c){return c.toUpperCase()})">Sentence case</button>'
        + '<button class="btn btn-secondary" onclick="var t=document.getElementById(\'cc-txt\'),r=\'\';for(var c of t.value)r+=c===c.toUpperCase()?c.toLowerCase():c.toUpperCase();t.value=r">tOGGLE cASE</button>'
        + '</div>'
        + '<div class="result-box" style="margin-top:12px;font-size:13px;color:#6b7280;text-align:center" id="cc-stats">Characters: 0 | Words: 0</div>';
      document.getElementById('cc-txt').oninput = function() {
        var t = this.value, w = t.trim() ? t.trim().split(/\s+/).length : 0;
        document.getElementById('cc-stats').textContent = 'Characters: '+t.length+' | Words: '+w;
      };
    }
  },

  'unit-converter': {
    render: function(c) {
      var units = {Length:[{v:'m',l:'Meter'},{v:'km',l:'Kilometer'},{v:'cm',l:'Centimeter'},{v:'mm',l:'Millimeter'},{v:'ft',l:'Foot'},{v:'in',l:'Inch'}],
        Weight:[{v:'kg',l:'Kilogram'},{v:'g',l:'Gram'},{v:'lb',l:'Pound'},{v:'oz',l:'Ounce'}],
        Temperature:[{v:'c',l:'Celsius'},{v:'f',l:'Fahrenheit'},{v:'k',l:'Kelvin'}],
        Area:[{v:'sqm',l:'Sq Meter'},{v:'sqft',l:'Sq Foot'},{v:'acre',l:'Acre'},{v:'ha',l:'Hectare'}]};
      var factors = {m:1,km:0.001,cm:100,mm:1000,ft:3.28084,in:39.3701,kg:1,g:1000,lb:2.20462,oz:35.274,
        sqm:1,sqft:10.7639,acre:0.000247105,ha:0.0001,c:1,f:1,k:1};
      c.innerHTML = '<div class="form-group"><label>Category</label><select class="form-select" id="uc-cat">'
        + Object.keys(units).map(function(k){return '<option value="'+k+'">'+k+'</option>';}).join('')
        + '</select></div>'
        + '<div class="form-group"><label>From</label><select class="form-select" id="uc-from"></select></div>'
        + '<div class="form-group"><label>Value</label><input type="number" class="form-input" id="uc-val" value="1"></div>'
        + '<div class="form-group"><label>To</label><select class="form-select" id="uc-to"></select></div>'
        + '<div class="result-box"><div class="result-amount" id="uc-res">-</div></div>';
      function pop(cat) {
        var u = units[cat] || [];
        var f = document.getElementById('uc-from'), t = document.getElementById('uc-to');
        f.innerHTML = ''; t.innerHTML = '';
        u.forEach(function(x,i){ f.innerHTML += '<option value="'+x.v+'">'+x.l+'</option>'; t.innerHTML += '<option value="'+x.v+'">'+x.l+'</option>'; });
        if(u.length>1) t.value = u[1].v; convert();
      }
      function convert() {
        var cat = document.getElementById('uc-cat').value;
        var from = document.getElementById('uc-from').value;
        var to = document.getElementById('uc-to').value;
        var v = parseFloat(document.getElementById('uc-val').value) || 0;
        if(cat === 'Temperature') {
          var cels = from==='c'?v:from==='f'?(v-32)*5/9:v-273.15;
          document.getElementById('uc-res').textContent = to==='c'?cels.toFixed(2):to==='f'?(cels*9/5+32).toFixed(2):(cels+273.15).toFixed(2);
        } else {
          document.getElementById('uc-res').textContent = (v * (factors[to]||1) / (factors[from]||1)).toFixed(6);
        }
      }
      document.getElementById('uc-cat').onchange = function(){ pop(this.value); };
      document.getElementById('uc-from').onchange = convert;
      document.getElementById('uc-to').onchange = convert;
      document.getElementById('uc-val').oninput = convert;
      pop('Length');
    }
  },

  'upi-link-generator': {
    render: function(c) {
      c.innerHTML = '<div class="form-group"><label>UPI ID</label><input type="text" id="upi-id" class="form-input" value="name@paytm"></div>'
        + '<div class="form-group"><label>Name</label><input type="text" id="upi-name" class="form-input" value="Test User"></div>'
        + '<div class="form-group"><label>Amount (Rs)</label><input type="number" id="upi-amt" class="form-input" value="100"></div>'
        + '<button class="btn btn-primary btn-block" id="upi-btn">Generate UPI Link</button>'
        + '<div class="result-box" id="upi-res" style="display:none"></div>';
      document.getElementById('upi-btn').onclick = function() {
        var id = document.getElementById('upi-id').value || 'name@upi';
        var name = document.getElementById('upi-name').value || '';
        var amt = document.getElementById('upi-amt').value || '';
        var link = 'upi://pay?pa='+encodeURIComponent(id)+'&pn='+encodeURIComponent(name)+'&am='+amt+'&cu=INR';
        var qr = 'https://chart.googleapis.com/chart?cht=qr&chs=200x200&chl='+encodeURIComponent(link);
        document.getElementById('upi-res').style.display = 'block';
        document.getElementById('upi-res').innerHTML = '<div style="text-align:center"><img src="'+qr+'" alt="UPI QR" style="max-width:200px;border-radius:8px;border:1px solid #e5e7eb"></div>'
          + '<div style="margin-top:8px;text-align:center;word-break:break-all;font-size:13px;color:#6b7280">'+link+'</div>';
      };
    }
  }
};

// ─── ToolEngine public API ───────────────────────────────────────────────────

var ToolEngine = {
  init: function(config) {
    config = config || window.__TOOL_CONFIG || {};
    var slug = config.slug || '';
    var container = document.getElementById('tool-container');
    if (!container) {
      container = document.querySelector('.tool-container');
    }
    if (!container) return;
    renderTool(slug, container);
  },
  renderTool: renderTool,
  tools: tools
};

window.ToolEngine = ToolEngine;

// Auto-init on DOMContentLoaded if __TOOL_CONFIG is set
document.addEventListener('DOMContentLoaded', function() {
  if (window.__TOOL_CONFIG) {
    ToolEngine.init(window.__TOOL_CONFIG);
  }
});

})();