/**
 * Vision execute - Alpine component for camera_measure / dxf_compare tasks (#46).
 *
 * The operator takes (or picks) an image, `acquire(blob)` sends it to the Flask
 * proxy, and the result - quote table, outcome, failures, overlay - is shown on
 * the image. `acquire(blob)` is the single entry point on purpose: the agent
 * camera (#3) will call it with its own blob and reuse everything below.
 *
 * Config comes from window.__visionCfg (set by the template):
 *   executeUrl, imageUrlTpl (with a 0 placeholder for the result id), taskId,
 *   taskType, subtasks, labels.
 * Run context (lot, serial, production run) is read lazily through `ctx()`,
 * which the template binds to the parent task component.
 */
function visionExecute() {
  // Overlay colour per role (VisionSuite roles: reference, roi, found).
  const ROLE_COLORS = { reference: '#2563eb', found: '#16a34a', roi: '#f59e0b' };

  return {
    busy: false,
    error: '',
    result: null,      // last execute response
    imageSrc: '',      // object URL of the acquired image (shown under the overlay)
    ctx: () => ({}),   // replaced by the template: {lot, serial, runId}

    // Entry point shared with the future agent camera.
    async acquire(blob) {
      if (!blob || this.busy) return;
      const cfg = window.__visionCfg || {};
      this.busy = true;
      this.error = '';
      this.result = null;
      // Show the picked image at once: the overlay is drawn on top when the result arrives.
      if (this.imageSrc) URL.revokeObjectURL(this.imageSrc);
      this.imageSrc = URL.createObjectURL(blob);
      try {
        const c = this.ctx() || {};
        const fd = new FormData();
        fd.append('task_id', cfg.taskId);
        fd.append('task_type', cfg.taskType || '');
        fd.append('image', blob, blob.name || 'capture.jpg');
        fd.append('lot_number', c.lot || '');
        fd.append('serial_number', c.serial || '');
        if (c.runId) fd.append('production_run_id', c.runId);
        const csrf = document.querySelector('meta[name=csrf-token]')?.content || '';
        const resp = await fetch(cfg.executeUrl, {
          method: 'POST', headers: { 'X-CSRFToken': csrf }, body: fd,
        });
        const body = await resp.json().catch(() => ({}));
        if (!resp.ok || body.error) {
          this.error = body.detail || (cfg.labels && cfg.labels.requestFailed) || 'Error';
          return;
        }
        this.result = body;
        // Draw once Alpine has rendered the canvas.
        this.$nextTick(() => this.drawOverlay());
      } catch (e) {
        this.error = (cfg.labels && cfg.labels.requestFailed) || 'Error';
      } finally {
        this.busy = false;
      }
    },

    // Input change: take the file and allow picking the same one again.
    onPick(ev) {
      const f = ev.target.files && ev.target.files[0];
      ev.target.value = '';
      if (f) this.acquire(f);
    },

    // Image shown: the saved one from the server when available, else the local one.
    get shownImage() {
      const cfg = window.__visionCfg || {};
      if (this.result && this.result.vision_result_id && cfg.imageUrlTpl) {
        return cfg.imageUrlTpl.replace('/0/', '/' + this.result.vision_result_id + '/');
      }
      return this.imageSrc;
    },

    // Quote rows: server measurements joined with the subtask names.
    get rows() {
      const cfg = window.__visionCfg || {};
      const subs = cfg.subtasks || [];
      return ((this.result && this.result.measurements) || []).map((m) => {
        const st = subs.find((s) => s.id === m.subtask_id) || {};
        return {
          label: (st.marker_number ? st.marker_number + '. ' : '') + (st.measurement_type || st.name || '#' + m.subtask_id),
          value: m.value,
          unit: st.unit || 'mm',
          status: m.pass_fail,
        };
      });
    },

    statusClass(s) {
      // Same palette as the measurement markers of the manual flow.
      if (s === 'pass') return 'bg-measure-pass/20 text-measure-pass border border-measure-pass/40';
      if (s === 'fail') return 'bg-red-100 dark:bg-red-900/30 text-measure-fail border border-measure-fail/40';
      if (s === 'warning') return 'bg-amber-100 dark:bg-amber-900/30 text-measure-warning border border-measure-warning/40';
      return 'bg-[var(--bg-secondary)] text-[var(--text-muted)] border border-[var(--border-color)]';
    },

    // Canvas is sized to the natural image, so overlay coordinates (image px)
    // are used as they are and CSS scales the whole thing to the displayed size.
    drawOverlay() {
      const img = this.$refs.img, cv = this.$refs.overlay;
      if (!img || !cv || !img.naturalWidth) return;
      cv.width = img.naturalWidth;
      cv.height = img.naturalHeight;
      const g = cv.getContext('2d');
      g.clearRect(0, 0, cv.width, cv.height);
      g.lineWidth = Math.max(2, cv.width / 400);
      g.lineJoin = 'round';
      for (const item of ((this.result && this.result.overlay) || [])) {
        const rows = item.rows || [], cols = item.cols || [];
        if (!rows.length || rows.length !== cols.length) continue;
        g.strokeStyle = ROLE_COLORS[item.role] || '#ef4444';
        g.beginPath();
        g.moveTo(cols[0], rows[0]);
        for (let i = 1; i < rows.length; i++) g.lineTo(cols[i], rows[i]);
        g.stroke();
      }
    },
  };
}