import { describe, expect, it } from "vitest";
import { content, type FixedPosition } from "../src/index";
import { offsetPosition } from "../src/data/locations";
// Vite reads the lockfile as text at test time.
import lockfile from "../../../pnpm-lock.yaml?raw";

function point(p: FixedPosition) {
  const a = (p.angleDegrees * Math.PI) / 180;
  return { x: p.radiusMillionKm * Math.cos(a), y: p.radiusMillionKm * Math.sin(a) };
}
function distance(fromId: string, toId: string): number {
  const a = point(content.location(fromId)!.position);
  const b = point(content.location(toId)!.position);
  return Math.hypot(b.x - a.x, b.y - a.y);
}

describe("fixed map (Step 15.1, decision 0.5.93)", () => {
  it("gives every location a fixed position", () => {
    for (const location of content.locations) {
      expect(location.position.radiusMillionKm, location.id).toBeGreaterThan(0);
      expect(Number.isFinite(location.position.angleDegrees), location.id).toBe(true);
    }
  });

  it("defines the Moon as an offset from Earth", () => {
    const moon = content.location("moon")!;
    expect(moon.orbitParent).toEqual({ locationId: "earth", offsetMillionKm: 0.384 });
    expect(moon.position).toEqual(offsetPosition(content.location("earth")!.position, 0.384));
    expect(distance("earth", "moon")).toBeCloseTo(0.384, 6);
  });

  it("puts every child body at its parent plus its offset", () => {
    for (const location of content.locations.filter((l) => l.orbitParent)) {
      const { locationId, offsetMillionKm } = location.orbitParent!;
      const parent = content.location(locationId)!;
      expect(location.position, location.id).toEqual(
        offsetPosition(parent.position, offsetMillionKm),
      );
    }
  });

  it.each([
    ["earth", "mars", 201],
    ["mars", "ceres-station", 202],
    ["earth", "ceres-station", 402],
    ["ceres-station", "jupiter-cloud-platform", 393],
    ["mars", "jupiter-cloud-platform", 592],
    ["earth", "jupiter-cloud-platform", 792],
  ])("puts %s–%s at about %i M km (CR-015 §2, within 2 %)", (from, to, expected) => {
    const d = distance(from, to);
    expect(Math.abs(d - expected) / expected).toBeLessThan(0.02);
    expect(distance(to, from)).toBeCloseTo(d, 9);
  });

  it("no longer depends on astronomy-engine", () => {
    expect(lockfile).not.toContain("astronomy-engine");
  });
});