// Render per-frame signals (contact_l, contact_r, grasp, motion, trust) into 5 mini SVGs.
// Each SVG is 200x18 viewBox. We scale to 0..1 vertically (motion uses log(1+x)/log(1+max)).

const VB_W = 200, VB_H = 18;

function clearSvg(svg) {
  while (svg.firstChild) svg.removeChild(svg.firstChild);
}

function pathFromSeries(values, normalize) {
  if (!values || values.length === 0) return '';
  const n = values.length;
  let pts = [];
  for (let i = 0; i < n; i++) {
    const x = (i / Math.max(n - 1, 1)) * VB_W;
    const v = normalize(values[i]);
    const y = VB_H - v * VB_H;
    pts.push(`${i === 0 ? 'M' : 'L'}${x.toFixed(2)},${y.toFixed(2)}`);
  }
  return pts.join(' ');
}

function fillBars(svg, values, normalize, color) {
  // For binary trust: render as horizontal bars where True
  const n = values.length;
  if (n === 0) return;
  const w = VB_W / n;
  let i = 0;
  while (i < n) {
    if (values[i]) {
      let j = i;
      while (j < n && values[j]) j++;
      const rect = document.createElementNS('http://www.w3.org/2000/svg', 'rect');
      rect.setAttribute('x', (i * w).toFixed(2));
      rect.setAttribute('y', '4');
      rect.setAttribute('width', ((j - i) * w).toFixed(2));
      rect.setAttribute('height', String(VB_H - 8));
      rect.setAttribute('fill', color);
      rect.setAttribute('opacity', '0.7');
      svg.appendChild(rect);
      i = j;
    } else {
      i++;
    }
  }
}

function drawArea(svg, values, normalize, fill, stroke) {
  const n = values.length;
  if (n === 0) return;
  let pts = [`M0,${VB_H}`];
  for (let i = 0; i < n; i++) {
    const x = (i / Math.max(n - 1, 1)) * VB_W;
    const v = Math.max(0, Math.min(1, normalize(values[i])));
    const y = VB_H - v * VB_H;
    pts.push(`L${x.toFixed(2)},${y.toFixed(2)}`);
  }
  pts.push(`L${VB_W},${VB_H}Z`);
  const path = document.createElementNS('http://www.w3.org/2000/svg', 'path');
  path.setAttribute('d', pts.join(' '));
  path.setAttribute('fill', fill);
  path.setAttribute('stroke', stroke);
  path.setAttribute('stroke-width', '0.8');
  svg.appendChild(path);
}

function addPlayhead(svg, frac) {
  const x = frac * VB_W;
  const line = document.createElementNS('http://www.w3.org/2000/svg', 'line');
  line.setAttribute('x1', x.toFixed(2));
  line.setAttribute('x2', x.toFixed(2));
  line.setAttribute('y1', '0');
  line.setAttribute('y2', String(VB_H));
  line.setAttribute('class', 'signal-playhead');
  line.setAttribute('stroke', 'var(--accent)');
  line.setAttribute('stroke-width', '1');
  svg.appendChild(line);
  return line;
}

export class SignalPanel {
  constructor() {
    this.svgs = {
      contact_l: document.getElementById('sig-contact-l'),
      contact_r: document.getElementById('sig-contact-r'),
      grasp: document.getElementById('sig-grasp'),
      motion: document.getElementById('sig-motion'),
      trust: document.getElementById('sig-trust'),
    };
    this.vals = {
      contact_l: document.getElementById('sig-val-contact-l'),
      contact_r: document.getElementById('sig-val-contact-r'),
      grasp: document.getElementById('sig-val-grasp'),
      motion: document.getElementById('sig-val-motion'),
      trust: document.getElementById('sig-val-trust'),
    };
    this.playheads = {};
    this.data = null;
  }

  setData(timeseries) {
    this.data = timeseries;
    if (!timeseries) {
      Object.values(this.svgs).forEach(clearSvg);
      Object.values(this.vals).forEach(v => v.textContent = '-');
      return;
    }
    const scene = timeseries.scene || {};
    this._render('contact_l', scene.contact_l || [], v => v, 'rgba(217,119,87,0.25)', 'oklch(0.68 0.18 40)');
    this._render('contact_r', scene.contact_r || [], v => v, 'rgba(106,148,96,0.25)', 'oklch(0.58 0.12 150)');
    this._render('grasp',     scene.grasp || [],     v => v, 'rgba(160,88,72,0.30)', 'oklch(0.58 0.18 30)');

    // motion: log scale
    const motion = scene.motion || [];
    const maxMotion = Math.max(1, ...motion.map(v => v || 0));
    this._render('motion', motion, v => Math.log1p(v) / Math.log1p(maxMotion), 'rgba(120,120,160,0.22)', 'oklch(0.55 0.10 240)');

    // trust: union over per-object trust booleans (if any object trusted that frame, mark trusted)
    const perObj = timeseries.per_object || {};
    const n = timeseries.n_frames || (motion.length || 0);
    const trustUnion = new Array(n).fill(false);
    Object.values(perObj).forEach(o => {
      const arr = o.trust || [];
      for (let i = 0; i < n; i++) if (arr[i]) trustUnion[i] = true;
    });
    clearSvg(this.svgs.trust);
    fillBars(this.svgs.trust, trustUnion, v => v ? 1 : 0, 'oklch(0.68 0.18 40)');
    // playhead overlay
    this.playheads.trust = addPlayhead(this.svgs.trust, 0);
    this._lastTrust = trustUnion;
  }

  _render(key, series, normalize, fill, stroke) {
    const svg = this.svgs[key];
    clearSvg(svg);
    drawArea(svg, series, normalize, fill, stroke);
    this.playheads[key] = addPlayhead(svg, 0);
  }

  setPlayheadFrame(frameIdx) {
    if (!this.data) return;
    const n = this.data.n_frames || 1;
    const frac = Math.max(0, Math.min(1, frameIdx / Math.max(n - 1, 1)));
    Object.values(this.playheads).forEach(line => {
      if (!line) return;
      const x = (frac * VB_W).toFixed(2);
      line.setAttribute('x1', x);
      line.setAttribute('x2', x);
    });
    // update value labels
    const scene = this.data.scene || {};
    const f = Math.max(0, Math.min(n - 1, Math.round(frameIdx)));
    const fmt = (v) => (v == null ? '-' : (typeof v === 'number' ? v.toFixed(2) : String(v)));
    this.vals.contact_l.textContent = fmt(scene.contact_l && scene.contact_l[f]);
    this.vals.contact_r.textContent = fmt(scene.contact_r && scene.contact_r[f]);
    this.vals.grasp.textContent = fmt(scene.grasp && scene.grasp[f]);
    this.vals.motion.textContent = fmt(scene.motion && scene.motion[f]);
    this.vals.trust.textContent = (this._lastTrust && this._lastTrust[f]) ? 'yes' : 'no';
  }
}


// ─── Per-object state timeline (static / grasped / moving) ────────
// Rendered into #state-timeline-rows from signals.json.per_object[oid].state
// One row per object: prompt label + horizontal SVG strip + per-frame value.
// Colors must match the .state-chip classes in styles.css.

const STATE_COLOR = {
  static:        'oklch(0.78 0.01 240)',   // light gray
  grasped_l:     'oklch(0.70 0.16 50)',    // warm orange = left hand
  grasped_r:     'oklch(0.60 0.20 20)',    // red-orange = right hand
  grasped_both:  'oklch(0.42 0.20 15)',    // deep red = both hands
  moving:        'oklch(0.55 0.10 240)',   // cool blue
  // back-compat: clips processed before the L/R split write plain "grasped"
  grasped:       'oklch(0.58 0.18 30)',
};

export class StateTimelinePanel {
  constructor() {
    this.container = document.getElementById('state-timeline-rows');
    this.rows = [];    // [{oid, svg, valEl, playhead, states}]
    this.nFrames = 0;
  }

  setData(timeseries, scene) {
    if (!this.container) return;
    this.container.innerHTML = '';
    this.rows = [];
    this.nFrames = (timeseries && timeseries.n_frames) || 0;

    const perObj = (timeseries && timeseries.per_object) || {};
    const objs = (scene && scene.reconstruction && scene.reconstruction.objects) || [];

    // Need at least one object with a state array to render anything
    const haveState = Object.values(perObj).some(o => Array.isArray(o.state));
    if (!haveState) {
      const empty = document.createElement('div');
      empty.style.cssText = 'font-size:10px;color:var(--ink-3);padding:4px 0;';
      empty.textContent = 'No state data; clip may pre-date the state-machine refresh.';
      this.container.appendChild(empty);
      return;
    }

    objs.forEach(o => {
      const oidKey = String(o.id);
      const po = perObj[oidKey] || {};
      const states = po.state || [];
      if (!states.length) return;

      const row = document.createElement('div');
      row.className = 'state-row';

      const label = document.createElement('div');
      label.className = 'state-label';
      label.style.color = o.color_hex || 'inherit';
      label.title = o.prompt || `obj ${o.id}`;
      label.textContent = (o.prompt || `obj ${o.id}`).slice(0, 18);
      row.appendChild(label);

      const svg = document.createElementNS('http://www.w3.org/2000/svg', 'svg');
      svg.setAttribute('preserveAspectRatio', 'none');
      svg.setAttribute('viewBox', `0 0 ${VB_W} ${VB_H}`);
      // Paint segments
      const n = states.length;
      let i = 0;
      const w = VB_W / Math.max(n, 1);
      while (i < n) {
        const s = states[i];
        let j = i;
        while (j < n && states[j] === s) j++;
        const rect = document.createElementNS('http://www.w3.org/2000/svg', 'rect');
        rect.setAttribute('x', (i * w).toFixed(2));
        rect.setAttribute('y', '2');
        rect.setAttribute('width', ((j - i) * w).toFixed(2));
        rect.setAttribute('height', String(VB_H - 4));
        rect.setAttribute('fill', STATE_COLOR[s] || 'oklch(0.78 0.01 240)');
        svg.appendChild(rect);
        i = j;
      }
      const playhead = addPlayhead(svg, 0);
      row.appendChild(svg);

      const valEl = document.createElement('div');
      valEl.className = 'state-value';
      valEl.textContent = '-';
      row.appendChild(valEl);

      this.container.appendChild(row);
      this.rows.push({ oid: o.id, svg, valEl, playhead, states });
    });
  }

  setPlayheadFrame(frameIdx) {
    if (!this.rows.length) return;
    const n = this.nFrames || 1;
    const frac = Math.max(0, Math.min(1, frameIdx / Math.max(n - 1, 1)));
    const x = (frac * VB_W).toFixed(2);
    const f = Math.max(0, Math.min(n - 1, Math.round(frameIdx)));
    for (const r of this.rows) {
      if (r.playhead) {
        r.playhead.setAttribute('x1', x);
        r.playhead.setAttribute('x2', x);
      }
      r.valEl.textContent = r.states[f] || '-';
    }
  }
}