{% extends "base.html" %}
{% block content %}
<h1>Usage Dashboard</h1>

<div class="card">
  <div style="display:flex; justify-content:space-between; align-items:baseline; flex-wrap:wrap; gap:0.5rem;">
    <h3 style="margin:0;">Live system status</h3>
    <span class="muted" id="live-updated">Loading&hellip;</span>
  </div>
  <div id="live-flow-wrap" style="margin-top:0.5rem;">
    <svg id="live-flow" viewBox="0 0 600 230" style="width:100%; max-width:560px; display:block; margin:0 auto;">
      <defs>
        <marker id="arrow" viewBox="0 0 10 10" refX="8" refY="5" markerWidth="6" markerHeight="6" orient="auto-start-reverse">
          <path d="M0,0 L10,5 L0,10 z" fill="context-stroke"></path>
        </marker>
      </defs>

      <!-- Solar -> House -->
      <path id="flow-solar-house" d="M 260 70 C 200 130, 180 150, 150 175" fill="none" stroke="var(--accent)" stroke-width="3"
            stroke-dasharray="6 6" marker-end="url(#arrow)" class="flow-line"></path>
      <!-- Solar -> Grid (export) / Grid -> House (import), same path, direction/color/arrow flipped by JS -->
      <path id="flow-solar-grid" d="M 340 70 C 400 130, 420 150, 450 175" fill="none" stroke="var(--good)" stroke-width="3"
            stroke-dasharray="6 6" marker-end="url(#arrow)" class="flow-line"></path>

      <!-- Solar node -->
      <g transform="translate(300 55)">
        <circle r="34" fill="var(--card-bg)" stroke="var(--border)" stroke-width="1.5"></circle>
        <g stroke="var(--fg)" stroke-width="2" fill="none" stroke-linecap="round">
          <circle r="8" cy="0"></circle>
          <line x1="0" y1="-18" x2="0" y2="-13"></line>
          <line x1="0" y1="13" x2="0" y2="18"></line>
          <line x1="-18" y1="0" x2="-13" y2="0"></line>
          <line x1="13" y1="0" x2="18" y2="0"></line>
          <line x1="-12.7" y1="-12.7" x2="-9.2" y2="-9.2"></line>
          <line x1="9.2" y1="9.2" x2="12.7" y2="12.7"></line>
          <line x1="12.7" y1="-12.7" x2="9.2" y2="-9.2"></line>
          <line x1="-9.2" y1="9.2" x2="-12.7" y2="12.7"></line>
        </g>
      </g>
      <text x="300" y="10" text-anchor="middle" class="live-label">Solar</text>
      <text id="live-generation" x="300" y="107" text-anchor="middle" class="live-value">&mdash;</text>

      <!-- House node -->
      <g transform="translate(120 195)">
        <circle r="34" fill="var(--card-bg)" stroke="var(--border)" stroke-width="1.5"></circle>
        <path d="M -14,4 L -14,-4 L 0,-16 L 14,-4 L 14,4 L 8,4 L 8,14 L -8,14 L -8,4 Z"
              fill="none" stroke="var(--fg)" stroke-width="2" stroke-linejoin="round"></path>
      </g>
      <text x="120" y="163" text-anchor="middle" class="live-label">House</text>
      <text id="live-load" x="120" y="230" text-anchor="middle" class="live-value">&mdash;</text>

      <!-- Grid node -->
      <g transform="translate(480 195)">
        <circle r="34" fill="var(--card-bg)" stroke="var(--border)" stroke-width="1.5"></circle>
        <path d="M 2,-16 L -8,2 L -1,2 L -3,16 L 10,-4 L 2,-4 Z"
              fill="none" stroke="var(--fg)" stroke-width="2" stroke-linejoin="round"></path>
      </g>
      <text x="480" y="163" text-anchor="middle" class="live-label">Grid</text>
      <text id="live-grid" x="480" y="230" text-anchor="middle" class="live-value">&mdash;</text>
    </svg>
  </div>
</div>

<div class="card" id="summary-card">
  <div class="muted">Loading summary&hellip;</div>
</div>

<div class="card">
  <div style="display:flex; justify-content:space-between; align-items:center;">
    <h3 style="margin:0;">Generation / load / import / export</h3>
    <select id="range-select">
      <option value="7">Last 7 days</option>
      <option value="30" selected>Last 30 days</option>
      <option value="90">Last 90 days</option>
      <option value="365">Last 365 days</option>
      <option value="all">All time</option>
    </select>
  </div>
  <div class="chart-container">
    <canvas id="usage-chart"></canvas>
  </div>
</div>

<script>
const FLOW_REFRESH_MS = 30000;

function fmtKw(kw) {
  if (kw === null || kw === undefined) return '&mdash;';
  return `${kw.toFixed(1)} kW`;
}

function fmtAgo(isoTs) {
  const seconds = Math.max(0, Math.round((Date.now() - new Date(isoTs).getTime()) / 1000));
  if (seconds < 90) return 'updated just now';
  const minutes = Math.round(seconds / 60);
  if (minutes < 60) return `updated ${minutes} min ago`;
  return `updated ${Math.round(minutes / 60)} h ago`;
}

async function loadLiveFlow() {
  const el = document.getElementById('live-updated');
  const data = await fetch('/api/usage/live').then(r => r.json());
  if (!data.available) {
    el.textContent = 'No data yet';
    return;
  }
  el.textContent = fmtAgo(data.ts);

  const generation = data.generation_kw ?? 0;
  const load = data.load_kw ?? 0;
  const importKw = data.import_kw ?? 0;
  const exportKw = data.export_kw ?? 0;
  const selfConsumed = Math.max(0, generation - exportKw);

  document.getElementById('live-generation').textContent = fmtKw(generation).replace('&mdash;', '—');
  document.getElementById('live-load').textContent = fmtKw(load).replace('&mdash;', '—');

  const solarHouseLine = document.getElementById('flow-solar-house');
  solarHouseLine.style.display = selfConsumed > 0.05 ? '' : 'none';

  const gridLine = document.getElementById('flow-solar-grid');
  const gridLabel = document.getElementById('live-grid');
  if (exportKw > 0.05) {
    gridLine.setAttribute('stroke', 'var(--good)');
    gridLine.setAttribute('d', 'M 340 70 C 400 130, 420 150, 450 175');
    gridLine.style.display = '';
    gridLabel.textContent = `${fmtKw(exportKw).replace('&mdash;', '—')} exporting`;
  } else if (importKw > 0.05) {
    gridLine.setAttribute('stroke', 'var(--bad)');
    // Same curve, reversed direction (grid -> solar node's side, feeding the house).
    gridLine.setAttribute('d', 'M 450 175 C 420 150, 400 130, 340 70');
    gridLine.style.display = '';
    gridLabel.textContent = `${fmtKw(importKw).replace('&mdash;', '—')} importing`;
  } else {
    gridLine.style.display = 'none';
    gridLabel.textContent = 'no grid flow';
  }
}

async function loadDashboard(days) {
  const [summary, daily] = await Promise.all([
    fetch(`/api/usage/summary?days=${days}`).then(r => r.json()),
    fetch(`/api/usage/daily?days=${days}`).then(r => r.json()),
  ]);

  const summaryEl = document.getElementById('summary-card');
  if (!summary.days_with_data) {
    summaryEl.innerHTML = '<div class="muted">No usage data yet. If you\'re running on mock data, it should appear within a few minutes of startup.</div>';
  } else {
    const revenue = summary.net_revenue_dollars;
    const revenueHtml = revenue === null || revenue === undefined
      ? ''
      : `<div><div class="muted">Net revenue</div><strong class="${revenue >= 0 ? 'savings-positive' : 'savings-negative'}">${revenue >= 0 ? '+$' : '-$'}${Math.abs(revenue).toFixed(2)}</strong></div>`;
    summaryEl.innerHTML = `
      <div class="muted">${summary.first_day} &rarr; ${summary.last_day} (${summary.days_with_data} days with data)</div>
      <div style="display:flex; gap:2rem; margin-top:0.75rem; flex-wrap:wrap;">
        <div><div class="muted">Generated</div><strong>${summary.generation_kwh} kWh</strong></div>
        <div><div class="muted">Consumed</div><strong>${summary.load_kwh} kWh</strong></div>
        <div><div class="muted">Imported</div><strong>${summary.import_kwh} kWh</strong></div>
        <div><div class="muted">Exported</div><strong>${summary.export_kwh} kWh</strong></div>
        ${revenueHtml}
      </div>
    `;
  }

  const ctx = document.getElementById('usage-chart');
  if (window.usageChart) window.usageChart.destroy();

  // Chart.js can measure a stale (pre-layout) container size when created
  // synchronously during initial page parse. Wait a couple of frames so the
  // browser has actually settled the flex/grid layout first.
  await new Promise((resolve) => requestAnimationFrame(() => requestAnimationFrame(resolve)));

  window.usageChart = new Chart(ctx, {
    type: 'bar',
    data: {
      labels: daily.map(d => d.date),
      datasets: [
        { label: 'Generation', data: daily.map(d => d.generation_kwh), backgroundColor: '#facc15' },
        { label: 'Load', data: daily.map(d => d.load_kwh), backgroundColor: '#60a5fa' },
        { label: 'Import', data: daily.map(d => d.import_kwh), backgroundColor: '#f87171' },
        { label: 'Export', data: daily.map(d => d.export_kwh), backgroundColor: '#4ade80' },
      ],
    },
    options: {
      responsive: true,
      maintainAspectRatio: false,
      animation: false,
      scales: { x: { stacked: false }, y: { title: { display: true, text: 'kWh' } } },
    },
  });
}

const rangeSelect = document.getElementById('range-select');
rangeSelect.addEventListener('change', () => loadDashboard(rangeSelect.value));
loadDashboard(rangeSelect.value);

loadLiveFlow();
setInterval(loadLiveFlow, FLOW_REFRESH_MS);
</script>
{% endblock %}