import { describe, expect, it } from 'vitest';
import { loadEligiblePlanes, slotsUsedFor } from './RightPane';
import type { PackageState, PlaneState, StateSnapshot } from '@/lib/game/state';

// v0.12.0 — the package-model picker rules: a plane can LOAD a package only while
// it is GROUNDED at the package's origin with a free slot (capacity from the
// snapshot catalog; expired packages still occupy theirs). The Load button acts
// directly on the single eligible plane, or shows a picker when several qualify.

const CATALOG = [
  { model: 'atr72', label: 'ATR 72-600', price: 200_000, maxFuel: 6300, burnPerKm: 1.75, speedKmh: 510, capacity: 6 },
];

function plane(over: Partial<PlaneState> & Pick<PlaneState, 'id'>): PlaneState {
  return {
    model: 'atr72',
    status: 'available',
    fuel: 100,
    maxFuel: 100,
    locationIcao: 'EDDF',
    locationName: 'Frankfurt Main',
    destIcao: null,
    destName: null,
    departureSimTime: null,
    lat: 50,
    lon: 8.5,
    ...over,
  };
}

function pkg(over: Partial<PackageState> & Pick<PackageState, 'id'>): PackageState {
  return {
    originIcao: 'EDDF',
    originName: 'Frankfurt Main',
    destIcao: 'LEMD',
    destName: 'Madrid Barajas',
    reward: 1000,
    cargoType: 'mail',
    cargoCount: 4,
    deadlineSimTime: 1_000_000,
    status: 'open',
    planeId: null,
    createdSimTime: 0,
    ...over,
  };
}

function snap(planes: PlaneState[], packages: PackageState[] = []): StateSnapshot {
  return {
    account: { cash: 0, reputation: 0 },
    simState: { clockMs: 0, timeScale: 1, paused: false },
    planes,
    packages,
    catalog: CATALOG,
    fuelPricePerL: 0.8,
    sellFraction: 0.5,
  };
}

describe('slotsUsedFor', () => {
  it('counts loaded AND expired packages bound to the plane (both occupy a slot)', () => {
    const s = snap(
      [plane({ id: 'p1' })],
      [
        pkg({ id: 'a', status: 'loaded', planeId: 'p1' }),
        pkg({ id: 'b', status: 'expired', planeId: 'p1' }),
        pkg({ id: 'c', status: 'open', planeId: null }), // not on any plane
        pkg({ id: 'd', status: 'delivered', planeId: 'p1' }), // terminal — slot long freed
      ],
    );
    expect(slotsUsedFor(s, 'p1')).toBe(2);
  });

  it('is 0 for a plane with no bound cargo', () => {
    expect(slotsUsedFor(snap([plane({ id: 'p1' })]), 'p1')).toBe(0);
  });
});

describe('loadEligiblePlanes (Load button eligibility)', () => {
  it('includes only grounded planes at the package origin with a free slot', () => {
    const s = snap([
      plane({ id: 'at-origin' }), // eligible
      plane({ id: 'elsewhere', locationIcao: 'LEMD' }), // wrong airport
      plane({ id: 'in-flight', status: 'flying', destIcao: 'LEMD', destName: 'Madrid Barajas' }), // flying
    ]);
    expect(loadEligiblePlanes(s, pkg({ id: 'x' })).map((p) => p.id)).toEqual(['at-origin']);
  });

  it('excludes a plane whose slots are full (capacity from the catalog)', () => {
    const packages = Array.from({ length: 6 }, (_, i) =>
      pkg({ id: `fill-${i}`, status: 'loaded', planeId: 'full' }),
    );
    const s = snap([plane({ id: 'full' })], packages);
    expect(loadEligiblePlanes(s, pkg({ id: 'x' }))).toEqual([]);
  });

  it('a full plane with one slot freed by an expired package still counts as full', () => {
    const packages = [
      ...Array.from({ length: 5 }, (_, i) => pkg({ id: `fill-${i}`, status: 'loaded', planeId: 'full' })),
      pkg({ id: 'exp', status: 'expired', planeId: 'full' }), // occupies its slot
    ];
    const s = snap([plane({ id: 'full' })], packages);
    expect(loadEligiblePlanes(s, pkg({ id: 'x' }))).toEqual([]);
  });

  it('returns several planes when several qualify (picker case)', () => {
    const s = snap([plane({ id: 'a' }), plane({ id: 'b' })]);
    expect(loadEligiblePlanes(s, pkg({ id: 'x' })).map((p) => p.id).sort()).toEqual(['a', 'b']);
  });

  it('returns nothing when no plane is at the origin (Load stays disabled)', () => {
    const s = snap([plane({ id: 'far', locationIcao: 'LEMD' })]);
    expect(loadEligiblePlanes(s, pkg({ id: 'x' }))).toEqual([]);
  });

  it('a plane with an unknown model has no capacity → never eligible', () => {
    const s = snap([plane({ id: 'mystery', model: 'mystery' })]);
    expect(loadEligiblePlanes(s, pkg({ id: 'x' }))).toEqual([]);
  });
});