import { h } from 'preact';
import { useEffect, useState } from 'preact/hooks';
import { getMetaStore, getSignalStore } from './lib/stores';
import type { SignalRef, SignalMeta, SignalValue } from './lib/types';

interface Props {
  signal: SignalRef;
  onClose: () => void;
}

function qualityColor(q: string): string {
  switch (q) {
    case 'good':      return '#4ade80';
    case 'uncertain': return '#fbbf24';
    case 'bad':       return '#f87171';
    default:          return '#6b7280';
  }
}

function fmt(v: any): string {
  if (v === null || v === undefined) return '—';
  if (typeof v === 'number') return Number.isFinite(v) ? v.toPrecision(6).replace(/\.?0+$/, '') : String(v);
  if (Array.isArray(v)) return `[${v.slice(0, 8).map((x: any) => fmt(x)).join(', ')}${v.length > 8 ? ', …' : ''}]`;
  return String(v);
}

function fmtTs(ts: string | null): string {
  if (!ts) return '—';
  try { return new Date(ts).toLocaleString(); } catch { return ts; }
}

export default function InfoPanel({ signal, onClose }: Props) {
  const [meta, setMeta] = useState<SignalMeta | null>(null);
  const [sv, setSv] = useState<SignalValue>({ value: null, quality: 'unknown', ts: null });

  useEffect(() => {
    const unsubM = getMetaStore(signal).subscribe(setMeta);
    const unsubV = getSignalStore(signal).subscribe(setSv);
    return () => { unsubM(); unsubV(); };
  }, [signal.ds, signal.name]);

  return (
    <div class="info-panel">
      <div class="info-panel-header">
        <span class="info-panel-title">Signal Info</span>
        <button class="info-panel-close" onClick={onClose} title="Close">✕</button>
      </div>
      <div class="info-panel-body">
        <table class="info-table">
          <tbody>
            <tr><td class="info-key">Datasource</td><td class="info-val info-mono">{signal.ds}</td></tr>
            <tr><td class="info-key">Name</td><td class="info-val info-mono">{signal.name}</td></tr>
          </tbody>
        </table>

        <div class="info-sep" />

        <table class="info-table">
          <tbody>
            <tr>
              <td class="info-key">Value</td>
              <td class="info-val">
                <span
                  class="quality-dot"
                  style={`background:${qualityColor(sv.quality)};display:inline-block;margin-right:5px;vertical-align:middle;`}
                />
                {fmt(sv.value)}{meta?.unit ? ` ${meta.unit}` : ''}
              </td>
            </tr>
            <tr><td class="info-key">Quality</td><td class="info-val">{sv.quality}</td></tr>
            <tr><td class="info-key">Timestamp</td><td class="info-val">{fmtTs(sv.ts)}</td></tr>
          </tbody>
        </table>

        {meta && (
          <div>
            <div class="info-sep" />
            <table class="info-table">
              <tbody>
                <tr><td class="info-key">Type</td><td class="info-val">{meta.type}</td></tr>
                {meta.unit && <tr><td class="info-key">Unit</td><td class="info-val">{meta.unit}</td></tr>}
                <tr><td class="info-key">Writable</td><td class="info-val">{meta.writable ? 'Yes' : 'No'}</td></tr>
                {(meta.displayLow !== 0 || meta.displayHigh !== 0) && (
                  <tr>
                    <td class="info-key">Display range</td>
                    <td class="info-val">{meta.displayLow} … {meta.displayHigh}</td>
                  </tr>
                )}
              </tbody>
            </table>

            {meta.tags && meta.tags.length > 0 && (
              <div>
                <div class="info-sep" />
                <div class="info-section-hdr">Tags</div>
                <div style="display: flex; gap: 4px; flex-wrap: wrap; padding: 4px 0.75rem;">
                  {meta.tags.map(t => (
                    <span key={t} style="font-size: 0.7rem; background: #1e293b; color: #94a3b8; padding: 1px 6px; border-radius: 4px; border: 1px solid #334155;">
                      {t}
                    </span>
                  ))}
                </div>
              </div>
            )}

            {meta.properties && Object.keys(meta.properties).length > 0 && (
              <div>
                <div class="info-sep" />
                <div class="info-section-hdr">Properties</div>
                <table class="info-table">
                  <tbody>
                    {Object.entries(meta.properties).map(([k, v]) => (
                      <tr key={k}>
                        <td class="info-key">{k}</td>
                        <td class="info-val">{v}</td>
                      </tr>
                    ))}
                  </tbody>
                </table>
              </div>
            )}

            {meta.enumStrings && meta.enumStrings.length > 0 && (
              <div>
                <div class="info-sep" />
                <div class="info-section-hdr">States</div>
                <table class="info-table">
                  <tbody>
                    {meta.enumStrings.map((s, i) => (
                      <tr key={i}>
                        <td class="info-key">{i}</td>
                        <td class="info-val info-mono">{s}</td>
                      </tr>
                    ))}
                  </tbody>
                </table>
              </div>
            )}

            {meta.description && (
              <div>
                <div class="info-sep" />
                <div class="info-section-hdr">Description</div>
                <div class="info-desc">{meta.description}</div>
              </div>
            )}
          </div>
        )}
      </div>
    </div>
  );
}