(function(){
  function ensureLibs(){
    return new Promise((resolve)=>{
      const tick=()=>{ if(window.io && window.Chart) return resolve(); setTimeout(tick,50); };
      tick();
    });
  }

  const charts=new Map();
  const seriesData=new Map();
  const seriesUnit=new Map();
  const selectedRange=new Map();
  const maxWindowMs=10*60*60*1000;
  const rangeMap={
    '1m': 1*60*1000,
    '10m': 10*60*1000,
    '1h': 60*60*1000,
    '3h': 3*60*60*1000,
    '10h': 10*60*60*1000,
  };

  function isNum(v){ return typeof v==='number' && Number.isFinite(v); }

  function scale(v, unit){
    if(!isNum(v)) return {v, u:''};
    const u=(unit||'').toLowerCase();
    if(u==='%' || u==='pct' || u==='percent') return {v, u:'%'};
    if(u==='bps' || u==='bit/s' || u==='bits/s'){
      const steps=['bps','Kbps','Mbps','Gbps','Tbps'];
      let i=0, x=v;
      while(Math.abs(x)>=1000 && i<steps.length-1){ x/=1000; i++; }
      return {v:x, u:steps[i]};
    }
    if(u==='b/s' || u==='bytes/s' || u==='byte/s'){
      const steps=['B/s','KiB/s','MiB/s','GiB/s','TiB/s'];
      let i=0, x=v;
      while(Math.abs(x)>=1024 && i<steps.length-1){ x/=1024; i++; }
      return {v:x, u:steps[i]};
    }
    if(u==='b' || u==='bytes'){
      const steps=['B','KiB','MiB','GiB','TiB'];
      let i=0, x=v;
      while(Math.abs(x)>=1024 && i<steps.length-1){ x/=1024; i++; }
      return {v:x, u:steps[i]};
    }
    return {v, u:unit||''};
  }

  function fmt(v, unit){
    if(!isNum(v)) return '';
    const s=scale(v, unit);
    const a=Math.abs(s.v);
    const n = a>=100 ? s.v.toFixed(0) : a>=10 ? s.v.toFixed(1) : s.v.toFixed(2);
    return n + (s.u ? ' '+s.u : '');
  }

  function hash32(str){
    let h=2166136261;
    for(let i=0;i<str.length;i++){ h ^= str.charCodeAt(i); h = Math.imul(h, 16777619); }
    return h>>>0;
  }

  function colorFor(name){
    const hue = (hash32(String(name)) % 360);
    return {
      border:`hsl(${hue} 70% 45%)`,
      fill:`hsl(${hue} 70% 45% / 0.20)`
    };
  }

  function getRangeMs(widgetId){
    return rangeMap[selectedRange.get(widgetId) || '1h'] || rangeMap['1h'];
  }

  function pruneStore(store, latestTs){
    const minTs=latestTs-maxWindowMs;
    for(const name of Object.keys(store)){
      store[name]=store[name].filter(p=>p.x.getTime()>=minTs);
    }
  }

  function upsertChart(widgetId){
    const el=document.getElementById('chart-'+widgetId);
    if(!el) return null;
    if(charts.has(widgetId)) return charts.get(widgetId);

    const chart=new Chart(el.getContext('2d'),{
      type:'line',
      data:{datasets:[]},
      options:{
        animation:false,
        parsing:false,
        normalized:true,
        responsive:true,
        maintainAspectRatio:false,
        interaction:{mode:'nearest', intersect:false},
        scales:{
          x:{type:'time', time:{unit:'minute'}},
          y:{
            beginAtZero:false,
            ticks:{
              callback:(tick)=>{
                const uMap = seriesUnit.get(widgetId) || {};
                const units = Object.values(uMap).filter(Boolean);
                const uniq = [...new Set(units)];
                const u = uniq.length===1 ? uniq[0] : '';
                return u ? fmt(Number(tick), u) : tick;
              }
            }
          }
        },
        plugins:{
          legend:{display:true},
          tooltip:{
            callbacks:{
              label:(ctx)=>{
                const name=ctx.dataset.label||'';
                const y=ctx.parsed && isNum(ctx.parsed.y) ? ctx.parsed.y : null;
                const u=(seriesUnit.get(widgetId)||{})[name] || '';
                return name+': '+(y===null?'':fmt(y,u));
              }
            }
          }
        },
        elements:{point:{radius:0}}
      }
    });

    charts.set(widgetId, chart);
    seriesData.set(widgetId, {});
    seriesUnit.set(widgetId, {});
    if(!selectedRange.has(widgetId)) selectedRange.set(widgetId, '1h');
    return chart;
  }

  function setMeta(widgetId, txt){
    const m=document.getElementById('meta-'+widgetId);
    if(m) m.textContent=txt;
  }

  function escapeHtml(s){
    return String(s)
      .replaceAll('&','&amp;')
      .replaceAll('<','&lt;')
      .replaceAll('>','&gt;')
      .replaceAll('"','&quot;')
      .replaceAll("'",'&#039;');
  }

  function handleTable(msg){
    const tbl=document.querySelector("table[data-table-widget='"+msg.widget_id+"']");
    if(!tbl) return;
    const thead=tbl.querySelector('thead');
    const tbody=tbl.querySelector('tbody');
    const cols=msg.columns||[];
    thead.innerHTML='<tr>'+cols.map(c=>'<th>'+escapeHtml(c)+'</th>').join('')+'</tr>';
    tbody.innerHTML=(msg.rows||[]).map(r=>'<tr>'+cols.map(c=>'<td>'+escapeHtml(r[c] ?? '')+'</td>').join('')+'</tr>').join('');
  }

  function renderChart(widgetId, latestTs){
    const chart=upsertChart(widgetId);
    if(!chart) return;
    const store=seriesData.get(widgetId) || {};
    const rangeMs=getRangeMs(widgetId);
    const minTs=latestTs-rangeMs;

    chart.data.datasets = Object.keys(store).map(name=>{
      const c=colorFor(name);
      const data=(store[name]||[]).filter(p=>p.x.getTime()>=minTs);
      return {
        label:name,
        data,
        borderWidth:2,
        pointRadius:0,
        tension:0.15,
        fill:true,
        borderColor:c.border,
        backgroundColor:c.fill
      };
    });

    chart.options.scales.x.min=minTs;
    chart.options.scales.x.max=latestTs;
    chart.update('none');
  }

  function handleTimeseries(msg){
    const t=new Date(msg.ts);
    const widgetId=msg.widget_id;
    upsertChart(widgetId);

    const store=seriesData.get(widgetId) || {};
    const uMap=seriesUnit.get(widgetId) || {};

    for(const p of (msg.points||[])){
      if(p.value===null || p.value===undefined) continue;
      const s=p.series || 'value';
      if(!store[s]) store[s]=[];
      store[s].push({x:t, y:Number(p.value)});
      if(p.unit) uMap[s]=String(p.unit);
    }

    pruneStore(store, t.getTime());
    seriesData.set(widgetId, store);
    seriesUnit.set(widgetId, uMap);
    renderChart(widgetId, t.getTime());
    setMeta(widgetId, 'Updated: '+t.toLocaleTimeString()+' · Range: '+(selectedRange.get(widgetId)||'1h'));
  }

  function initRangeSelectors(){
    document.querySelectorAll('[data-range-widget]').forEach((el)=>{
      const widgetId=Number(el.getAttribute('data-range-widget'));
      selectedRange.set(widgetId, el.value || '1h');
      el.addEventListener('change', ()=>{
        selectedRange.set(widgetId, el.value || '1h');
        const store=seriesData.get(widgetId) || {};
        let latestTs=Date.now();
        for(const points of Object.values(store)){
          if(points.length){
            const ts=points[points.length-1].x.getTime();
            if(ts>latestTs) latestTs=ts;
          }
        }
        renderChart(widgetId, latestTs);
        setMeta(widgetId, 'Updated: '+new Date(latestTs).toLocaleTimeString()+' · Range: '+(selectedRange.get(widgetId)||'1h'));
      });
    });
  }

  async function main(){
    if(!window.MIKROMON || !window.MIKROMON.dashboardId) return;
    await ensureLibs();
    initRangeSelectors();

    const socket=io({transports:['polling'], upgrade:false});
    socket.on('connect', ()=>{
      socket.emit('join_dashboard', {dashboard_id: window.MIKROMON.dashboardId, public_token: window.MIKROMON.publicToken});
    });
    socket.on('metric', (msg)=>{
      if(!msg || !msg.widget_id) return;
      if(msg.type==='table') return handleTable(msg);
      return handleTimeseries(msg);
    });
  }

  document.addEventListener('DOMContentLoaded', main);
})();