/**
 * core-measure – Built-in V2-Plugin (Task A4.5).
 *
 * measure: 2 Klicks → Distanz+Winkel-Anzeige im Status. KEIN Element-Commit
 * (Legacy-Verhalten getreu — Messung ist Information, keine Zeichnung).
 * Distanzformatierung via bestehendem formatDistance(unit, scaleFactor).
 */
import type { PluginV2, ToolExtensionV2, FullToolContext } from '../../types';
import { formatDistance } from '../../../utils/format';

type MeasurePhase = 0 | 1; // 0=wartet auf Start, 1=wartet auf Ende
let measureStart: import('../../../tools/modification/geometry').Pt | null = null;

export const measureTool: ToolExtensionV2 = {
  manifest: {
    id: 'measure',
    label: 'Messen',
    icon: '\u2194',
    ribbonTab: 'view',
    tags: ['basic'],
    description: 'Distanz und Winkel zwischen zwei Punkten messen',
  },
  optionsSchema: [],
  handlers: {
    down(e, ctx) {
      const c = ctx as FullToolContext;
      if (!measureStart) {
        measureStart = e.world;
        ctx.setStatus('Messung: Endpunkt klicken');
        return;
      }
      // Zweiter Klick → anzeigen (Legacy-Ausgabeformat)
      const rawDist = Math.hypot(e.world.x - measureStart.x, e.world.y - measureStart.y);
      const angle = (Math.atan2(e.world.y - measureStart.y, e.world.x - measureStart.x) * 180) / Math.PI;
      const unit = (c.options.unit as string | undefined) ?? 'mm';
      const scale = (c.options.scaleFactor as number | undefined) ?? 1;
      const distStr = formatDistance(rawDist, unit as never, scale);
      ctx.setStatus(`distance: ${distStr}  angle: ${angle.toFixed(1)}\u00b0`);
      measureStart = null;
    },
    cancel(ctx) {
      measureStart = null;
      ctx.setStatus('Messung abgebrochen');
    },
  },
};

/** V2-Plugin: Messwerkzeuge. */
export const coreMeasurePlugin: PluginV2 = {
  manifest: {
    id: 'core-measure',
    name: 'Messen (Kern)',
    version: '1.0.0',
    author: 'web-cad team',
    description: 'Abstandswinkel-Messung ohne Element-Erzeugung.',
    category: 'tools',
    enabledByDefault: true,
  },
  tools: [measureTool],
};