import { describe, expect, it } from "vitest";
import {
  IRREGULAR_KEY_PRESETS,
  hasSecondRect,
  keyOrigin,
  keyOutline,
  keyRects,
} from "../src/domain/keyShape";
import { keyPath } from "../src/ui/phy/logic";

const isoEnter = IRREGULAR_KEY_PRESETS.find((p) => p.id === "iso-enter")!.size;
const asSet = (loop: { x: number; y: number }[]) => loop.map((p) => `${p.x},${p.y}`).sort();

describe("key shape", () => {
  it("fills missing second-rectangle fields with KLE's defaults", () => {
    expect(hasSecondRect({ w: 1, h: 1 })).toBe(false);
    expect(keyRects({ w: 1, h: 1 })).toEqual([{ x: 0, y: 0, w: 1, h: 1 }]);
    expect(keyRects({ w: 1.25, h: 1, w2: 1.75 })).toEqual([
      { x: 0, y: 0, w: 1.25, h: 1 },
      { x: 0, y: 0, w: 1.75, h: 1 },
    ]);
  });
  it("traces the ISO Enter as one clockwise loop of six corners", () => {
    const loops = keyOutline(isoEnter);
    expect(loops).toHaveLength(1);
    expect(asSet(loops[0]!)).toEqual(
      asSet([
        { x: -0.25, y: 0 },
        { x: 1.25, y: 0 },
        { x: 1.25, y: 2 },
        { x: 0, y: 2 },
        { x: 0, y: 1 },
        { x: -0.25, y: 1 },
      ]),
    );
    // Shoelace area is positive for a clockwise loop on a y-down screen.
    const loop = loops[0]!;
    const area = loop.reduce((sum, p, i) => {
      const q = loop[(i + 1) % loop.length]!;
      return sum + (p.x * q.y - q.x * p.y) / 2;
    }, 0);
    expect(area).toBeCloseTo(1.25 * 2 + 0.25);
  });
  it("traces a rectangle-in-rectangle as the outer rectangle", () => {
    expect(keyOutline({ w: 1, h: 1, w2: 2 }).map(asSet)).toEqual([
      asSet([
        { x: 0, y: 0 },
        { x: 2, y: 0 },
        { x: 2, y: 1 },
        { x: 0, y: 1 },
      ]),
    ]);
  });
  it("puts the bounding box's top-left where the key is placed", () => {
    expect(keyOrigin(isoEnter)).toEqual({ x: -0.25, y: 0 });
    expect(keyOrigin({ w: 1, h: 1 })).toEqual({ x: 0, y: 0 });
  });
  it("draws plain keys as rects and irregular ones as a path", () => {
    expect(keyPath({ w: 1, h: 1 })).toBeUndefined();
    expect(keyPath(isoEnter)).toMatch(/^M .* Z$/);
  });
});