import {
  LIFECYCLE_LABELS,
  PHASE_LABELS,
  PHASE_DESCRIPTIONS,
  SIGNAL_LABELS,
  NEXT_ACTION_KIND_LABELS,
} from '../constants/operating.js'
import { MILESTONE_STATUS_LABELS } from '../constants/status.js'

function formatDate(iso) {
  if (!iso) return '—'
  try {
    return new Date(iso).toLocaleDateString('de-DE')
  } catch {
    return iso
  }
}

export function SteeringSnapshotPanel({
  snapshot,
  loading,
  error,
  methods = [],
  canManageMethod = false,
  onMethodChange,
  methodBusy = false,
}) {
  if (loading) {
    return (
      <section className="card steering-snapshot">
        <p className="muted">Steuerungszustand wird geladen …</p>
      </section>
    )
  }

  if (error || !snapshot) {
    return (
      <section className="card steering-snapshot steering-snapshot--unavailable">
        <div className="section-header">
          <h2>Steuerungszustand</h2>
        </div>
        <p className="muted">
          {error || 'Snapshot nicht verfügbar — bitte Seite neu laden (Strg+F5).'}
        </p>
      </section>
    )
  }

  const {
    lifecycle_state,
    lifecycle_label,
    method_key,
    method_label,
    operating_phase,
    operating_phase_deprecated,
    phase_signals,
    counts,
    upcoming_milestones = [],
    next_actions = [],
  } = snapshot
  const displayLabel =
    lifecycle_label ||
    LIFECYCLE_LABELS[lifecycle_state] ||
    PHASE_LABELS[operating_phase] ||
    lifecycle_state ||
    operating_phase
  const phaseDesc = lifecycle_state
    ? null
    : PHASE_DESCRIPTIONS[operating_phase] || ''

  const statPills = [
    { label: 'Offen', value: counts.actions_open, warn: false },
    { label: 'Blockiert', value: counts.actions_blocked, warn: counts.actions_blocked > 0 },
    { label: 'Review', value: counts.actions_review_required, warn: counts.actions_review_required > 0 },
    { label: 'Blocker', value: counts.blockers_open, warn: counts.blockers_open > 0 },
  ]

  return (
    <section className="card steering-snapshot steering-snapshot--hero">
      <header className="steering-hero-header">
        <div>
          <p className="steering-hero-kicker">Leitfrage</p>
          <h2 className="steering-hero-title">
            Wo stehe ich — und was ist als Nächstes dran?
          </h2>
        </div>
        <span className="badge status-badge status-active steering-lifecycle-badge">
          {displayLabel}
        </span>
      </header>

      <div className="steering-hero-toolbar">
        {(method_label || canManageMethod) && (
          <p className="steering-method-row">
            <span className="muted">Methode: </span>
            {canManageMethod && methods.length > 0 ? (
              <select
                className="inline-select steering-method-select"
                value={method_key || 'generic_operating'}
                disabled={methodBusy}
                onChange={(e) => onMethodChange?.(e.target.value)}
                aria-label="Steuerungsmethode"
              >
                {methods.map((m) => (
                  <option key={m.key} value={m.key}>
                    {m.label}
                  </option>
                ))}
              </select>
            ) : (
              <strong>{method_label || method_key}</strong>
            )}
          </p>
        )}

        <ul className="steering-stat-pills" aria-label="Kurzüberblick">
          {statPills.map((pill) => (
            <li
              key={pill.label}
              className={`steering-stat-pill${pill.warn ? ' steering-stat-pill--warn' : ''}`}
            >
              <span className="steering-stat-pill-value">{pill.value}</span>
              <span className="steering-stat-pill-label">{pill.label}</span>
            </li>
          ))}
        </ul>
      </div>

      {phaseDesc && <p className="steering-phase-desc">{phaseDesc}</p>}

      {phase_signals?.length > 0 && (
        <p className="muted snapshot-signals">
          {phase_signals.map((s) => SIGNAL_LABELS[s] || s).join(' · ')}
        </p>
      )}

      <div className="steering-hero-columns">
        {next_actions.length > 0 && (
          <div className="steering-next-actions">
            <h3>Nächste Schritte</h3>
            <ol className="item-list compact-list">
              {next_actions.map((item, i) => (
                <li key={`${item.kind}-${i}`} className="list-item card-list-item compact">
                  <div className="list-item-main">
                    <span className="next-action-rank">{i + 1}</span>
                    <strong>{item.title}</strong>
                    <span className="muted list-item-sub">
                      {NEXT_ACTION_KIND_LABELS[item.kind] || item.kind}
                      {item.recommended_action ? ` — ${item.recommended_action}` : ''}
                    </span>
                  </div>
                </li>
              ))}
            </ol>
          </div>
        )}

        {upcoming_milestones.length > 0 && (
          <div className="steering-milestones">
            <h3>Meilenstein-Horizont</h3>
            <ul className="item-list compact-list">
              {upcoming_milestones.map((ms) => (
                <li key={ms.id} className="list-item card-list-item compact">
                  <div className="list-item-main">
                    <strong>{ms.title}</strong>
                    <span className="muted list-item-sub">
                      {MILESTONE_STATUS_LABELS[ms.status] || ms.status}
                      {ms.target_date ? ` · Ziel: ${formatDate(ms.target_date)}` : ''}
                    </span>
                  </div>
                </li>
              ))}
            </ul>
          </div>
        )}
      </div>

      {(counts.unlinked_blockers > 0 || counts.unlinked_evidence > 0) && (
        <p className="steering-unlinked-hint muted">
          {counts.unlinked_blockers > 0 && `${counts.unlinked_blockers} Blocker ohne Maßnahme`}
          {counts.unlinked_blockers > 0 && counts.unlinked_evidence > 0 && ' · '}
          {counts.unlinked_evidence > 0 && `${counts.unlinked_evidence} Nachweise ohne Maßnahme`}
          {' — unter „Erweitert“ verknüpfen oder aufräumen.'}
        </p>
      )}
    </section>
  )
}