wip

src/lib/cut-preview.ts

@@ -0,0 +1,60 @@
+import type { FlooringPiece, Point, SkirtingPiece } from './types';
+
+export interface PreviewBox {
+  x: number;
+  y: number;
+  width: number;
+  height: number;
+}
+export const exactMm = (value: number) =>
+  new Intl.NumberFormat('en-GB', { maximumFractionDigits: 3 }).format(value);
+export const viewBox = (box: PreviewBox) => `${box.x} ${box.y} ${box.width} ${box.height}`;
+
+export function flooringTemplate(piece: FlooringPiece): Point[] {
+  if (piece.template.length) return piece.template;
+  return piece.shaped
+    ? []
+    : [
+        { x: 0, y: 0 },
+        { x: piece.length, y: 0 },
+        { x: piece.length, y: piece.width },
+        { x: 0, y: piece.width },
+      ];
+}
+
+export function skirtingTemplate(piece: SkirtingPiece, thickness: number): Point[] {
+  if (piece.template?.length === 4) return piece.template;
+  if (piece.leftMitre !== 0 || piece.rightMitre !== 0) return [];
+  return [
+    { x: 0, y: 0 },
+    { x: piece.length, y: 0 },
+    { x: piece.length, y: thickness },
+    { x: 0, y: thickness },
+  ];
+}
+
+/** Padding changes the viewport only; all vertices stay in their original millimetres. */
+export function fullPreviewBox(length: number, width: number): PreviewBox {
+  const padding = Math.max(length, width, 1) * 0.06;
+  return { x: -padding, y: -padding, width: length + 2 * padding, height: width + 2 * padding };
+}
+
+/** Equal square windows enlarge both axes equally; a 45° mitre remains 45°. */
+export function skirtingEndBoxes(
+  template: Point[],
+  thickness: number,
+): { left: PreviewBox; right: PreviewBox } {
+  const [backLeft, backRight, frontRight, frontLeft] = template;
+  const side = Math.max(
+    1,
+    thickness * 3,
+    Math.abs(backLeft.x - frontLeft.x) / 0.76,
+    Math.abs(backRight.x - frontRight.x) / 0.76,
+  );
+  const padding = side * 0.12;
+  const common = { y: (thickness - side) / 2, width: side, height: side };
+  return {
+    left: { ...common, x: Math.min(backLeft.x, frontLeft.x) - padding },
+    right: { ...common, x: Math.max(backRight.x, frontRight.x) - side + padding },
+  };
+}