import fs from 'node:fs/promises';
import os from 'node:os';
import path from 'node:path';
import { eq } from 'drizzle-orm';
import { afterAll, beforeAll, describe, expect, it, vi } from 'vitest';
import { openGameDb, type GameDb } from '@/lib/db/client';
import * as schema from '@/lib/db/schema';
import { loadAirportsGeoJson } from '@/lib/airports';
import { FUEL_PRICE_PER_L, PLANE_TYPES, SELL_FRACTION } from './catalog';
import { HUB_ICAO } from './seed';
import {
  acceptContract,
  buyPlane,
  dispatchPlane,
  GameActionError,
  refuelPlane,
  sellPlane,
} from './actions';

// Action tests run against throwaway DB files (openGameDb) with fake timers so
// the seeded sim clock is a known constant. Actions are called directly (no tick —
// engine.runAction() wraps them in production; its lock/tick behavior is covered
// by the route tests and e2e).

let dir: string;
const T0 = 1_750_000_000_000; // seed moment / fake "now" at DB open

beforeAll(async () => {
  vi.useFakeTimers();
  vi.setSystemTime(T0);
  dir = await fs.mkdtemp(path.join(os.tmpdir(), 'flight-actions-'));
});

afterAll(async () => {
  vi.useRealTimers();
  await fs.rm(dir, { recursive: true, force: true });
});

async function freshDb(name: string): Promise<GameDb> {
  vi.setSystemTime(T0); // each throwaway DB is seeded at the same fake "now"
  return openGameDb(path.join(dir, name));
}

function expectActionError(promise: Promise<unknown>, status: number, messagePart?: RegExp) {
  return promise.then(
    () => {
      throw new Error(`expected GameActionError(${status}) but the action succeeded`);
    },
    (err) => {
      expect(err).toBeInstanceOf(GameActionError);
      expect((err as GameActionError).status).toBe(status);
      if (messagePart) expect((err as GameActionError).message).toMatch(messagePart);
    },
  );
}

// Insert an accepted contract EDDF → LEMD bound to nothing, for dispatch tests.
async function insertAcceptedContract(inst: GameDb, id = 'c-acc'): Promise<void> {
  await inst.db.insert(schema.contracts).values({
    id,
    originIcao: HUB_ICAO,
    destIcao: 'LEMD',
    reward: 5_000,
    cargoType: 'Passengers',
    cargoCount: 60,
    deadlineSimTime: T0 + 24 * 3_600_000,
    status: 'accepted',
    planeId: null,
    createdSimTime: T0,
  });
}

describe('acceptContract', () => {
  it('flips an open contract to accepted and persists it', async () => {
    const inst = await freshDb('acc-open.db');
    await acceptContract(inst, 'contract-1'); // seeded ids are contract-N

    const row = (await inst.db.select().from(schema.contracts).where(eq(schema.contracts.id, 'contract-1')))[0];
    expect(row.status).toBe('accepted');
  });

  it.each(['accepted', 'completed', 'expired'] as const)('rejects a %s contract with 409', async (status) => {
    const inst = await freshDb(`acc-${status}.db`);
    await inst.db.update(schema.contracts).set({ status }).where(eq(schema.contracts.id, 'contract-1'));

    await expectActionError(acceptContract(inst, 'contract-1'), 409, new RegExp(status));
  });

  it('rejects an unknown id with 404', async () => {
    const inst = await freshDb('acc-unknown.db');
    await expectActionError(acceptContract(inst, 'nope'), 404);
  });
});

describe('dispatchPlane', () => {
  it('binds the plane: flying + departure at current clock + origin coords, contract bound to plane', async () => {
    const inst = await freshDb('disp-ok.db');
    await insertAcceptedContract(inst);

    await dispatchPlane(inst, 'plane-starter', 'c-acc');

    const plane = (await inst.db.select().from(schema.planes))[0];
    expect(plane.status).toBe('flying');
    expect(plane.contractId).toBe('c-acc');
    expect(plane.departureSimTime).toBe(T0); // seeded clock, no tick in direct calls
    const fc = await loadAirportsGeoJson();
    const origin = fc.features.find((f) => f.properties.icao === HUB_ICAO)!.properties;
    expect(plane.lat).toBe(origin.lat);
    expect(plane.lon).toBe(origin.lon);
    // Fuel is frozen at the departure value while flying (live fuel is analytic).
    expect(plane.fuel).toBe(PLANE_TYPES.atr72.maxFuel);

    const contract = (await inst.db.select().from(schema.contracts).where(eq(schema.contracts.id, 'c-acc')))[0];
    expect(contract.planeId).toBe('plane-starter');
  });

  it.each(['open', 'completed', 'expired'] as const)('rejects a %s contract with 409 (must be accepted)', async (status) => {
    const inst = await freshDb(`disp-c${status}.db`);
    await inst.db.insert(schema.contracts).values({
      id: 'c-x', originIcao: HUB_ICAO, destIcao: 'LEMD', reward: 1, cargoType: 'Mail', cargoCount: 1,
      deadlineSimTime: T0 + 3_600_000, status, planeId: null, createdSimTime: T0,
    });

    await expectActionError(dispatchPlane(inst, 'plane-starter', 'c-x'), 409, new RegExp(status));
  });

  it('rejects an unknown contract id with 404', async () => {
    const inst = await freshDb('disp-cunknown.db');
    await expectActionError(dispatchPlane(inst, 'plane-starter', 'nope'), 404);
  });

  it('rejects an unknown plane id with 404', async () => {
    const inst = await freshDb('disp-punknown.db');
    await insertAcceptedContract(inst);
    await expectActionError(dispatchPlane(inst, 'ghost', 'c-acc'), 404);
  });

  it('rejects a flying plane with 409', async () => {
    const inst = await freshDb('disp-flying.db');
    await insertAcceptedContract(inst);
    await inst.db.update(schema.planes)
      .set({ status: 'flying', departureSimTime: T0, contractId: 'c-other' })
      .where(eq(schema.planes.id, 'plane-starter'));

    await expectActionError(dispatchPlane(inst, 'plane-starter', 'c-acc'), 409);
  });

  it('rejects a plane that is not at the origin with 409', async () => {
    const inst = await freshDb('disp-notatorigin.db');
    await insertAcceptedContract(inst); // originates at EDDF
    await inst.db.update(schema.planes)
      .set({ locationIcao: 'LEMD' })
      .where(eq(schema.planes.id, 'plane-starter'));

    await expectActionError(dispatchPlane(inst, 'plane-starter', 'c-acc'), 409, /not at|at LEMD/);
  });

  it('rejects a leg the plane cannot fuel with 409 (burn > fuel)', async () => {
    const inst = await freshDb('disp-nofuel.db');
    await insertAcceptedContract(inst); // EDDF → LEMD ≈ 1950 km × 1.75 L/km ≈ 3400 L
    await inst.db.update(schema.planes).set({ fuel: 1 }).where(eq(schema.planes.id, 'plane-starter'));

    await expectActionError(dispatchPlane(inst, 'plane-starter', 'c-acc'), 409, /insufficient fuel/i);
  });
});

describe('buyPlane', () => {
  it('deducts the full price and delivers a full-tank plane at the home base', async () => {
    const inst = await freshDb('buy-ok.db');
    await inst.db.update(schema.account).set({ cash: 500_000 });

    const before = (await inst.db.select().from(schema.planes)).length;
    const { planeId } = await buyPlane(inst, 'atr72');

    const account = (await inst.db.select().from(schema.account))[0];
    expect(account.cash).toBe(500_000 - PLANE_TYPES.atr72.price);

    const planes = await inst.db.select().from(schema.planes);
    expect(planes.length).toBe(before + 1);
    const bought = planes.find((p) => p.id === planeId)!;
    expect(bought.model).toBe('atr72');
    expect(bought.status).toBe('available');
    expect(bought.fuel).toBe(PLANE_TYPES.atr72.maxFuel); // full tank on delivery
    expect(bought.maxFuel).toBe(PLANE_TYPES.atr72.maxFuel);
    expect(bought.locationIcao).toBe(HUB_ICAO);
    const fc = await loadAirportsGeoJson();
    const hub = fc.features.find((f) => f.properties.icao === HUB_ICAO)!.properties;
    expect(bought.lat).toBe(hub.lat);
    expect(bought.lon).toBe(hub.lon);
  });

  it('rejects an unknown catalog model with 400', async () => {
    const inst = await freshDb('buy-unknown.db');
    await expectActionError(buyPlane(inst, 'boeing747'), 400, /unknown plane model/);
  });

  it('rejects the purchase when cash is below the price with 409', async () => {
    const inst = await freshDb('buy-poor.db'); // seeded cash is 20k < 200k
    await expectActionError(buyPlane(inst, 'atr72'), 409, /insufficient funds/i);
  });
});

describe('sellPlane', () => {
  it('pays out SELL_FRACTION of the catalog price and deletes the row', async () => {
    const inst = await freshDb('sell-ok.db');
    // A second plane so the starter is not "the last remaining one".
    await inst.db.insert(schema.planes).values({
      id: 'plane-extra', model: 'atr72', status: 'available', fuel: 100, maxFuel: PLANE_TYPES.atr72.maxFuel,
      locationIcao: HUB_ICAO, contractId: null, lat: 50, lon: 8, departureSimTime: null,
    });
    const cashBefore = (await inst.db.select().from(schema.account))[0].cash;

    const { payout } = await sellPlane(inst, 'plane-extra');

    expect(payout).toBe(Math.round(PLANE_TYPES.atr72.price * SELL_FRACTION * 100) / 100);
    const account = (await inst.db.select().from(schema.account))[0];
    expect(account.cash).toBeCloseTo(cashBefore + payout, 6);
    const ids = (await inst.db.select().from(schema.planes)).map((p) => p.id);
    expect(ids).not.toContain('plane-extra'); // row deleted
    expect(ids).toContain('plane-starter');
  });

  it('rejects selling a flying plane with 409', async () => {
    const inst = await freshDb('sell-flying.db');
    await inst.db.insert(schema.planes).values({
      id: 'plane-extra', model: 'atr72', status: 'flying', fuel: 100, maxFuel: PLANE_TYPES.atr72.maxFuel,
      locationIcao: HUB_ICAO, contractId: null, lat: 50, lon: 8, departureSimTime: T0,
    });

    await expectActionError(sellPlane(inst, 'plane-extra'), 409, /flying/);
  });

  it('rejects selling the last remaining plane with 409', async () => {
    const inst = await freshDb('sell-last.db'); // only the starter exists
    await expectActionError(sellPlane(inst, 'plane-starter'), 409, /last remaining/);
  });

  it('rejects an unknown id with 404', async () => {
    const inst = await freshDb('sell-unknown.db');
    await expectActionError(sellPlane(inst, 'ghost'), 404);
  });
});

describe('refuelPlane', () => {
  it('fills to maxFuel and deducts (maxFuel − fuel) × FUEL_PRICE_PER_L from cash', async () => {
    const inst = await freshDb('refuel-ok.db');
    await inst.db.update(schema.planes).set({ fuel: 1_000 }).where(eq(schema.planes.id, 'plane-starter'));
    const cashBefore = (await inst.db.select().from(schema.account))[0].cash;

    const { cost } = await refuelPlane(inst, 'plane-starter');

    expect(cost).toBe(Math.round((PLANE_TYPES.atr72.maxFuel - 1_000) * FUEL_PRICE_PER_L * 100) / 100);
    const plane = (await inst.db.select().from(schema.planes))[0];
    expect(plane.fuel).toBe(PLANE_TYPES.atr72.maxFuel);
    const account = (await inst.db.select().from(schema.account))[0];
    expect(account.cash).toBeCloseTo(cashBefore - cost, 6);
  });

  it('is a free no-op when the tank is already full', async () => {
    const inst = await freshDb('refuel-full.db'); // seeded starter is full
    const cashBefore = (await inst.db.select().from(schema.account))[0].cash;

    const { cost } = await refuelPlane(inst, 'plane-starter');

    expect(cost).toBe(0);
    expect((await inst.db.select().from(schema.account))[0].cash).toBe(cashBefore);
  });

  it('rejects a flying plane with 409', async () => {
    const inst = await freshDb('refuel-flying.db');
    await inst.db.update(schema.planes)
      .set({ status: 'flying', departureSimTime: T0, contractId: 'c-x' })
      .where(eq(schema.planes.id, 'plane-starter'));

    await expectActionError(refuelPlane(inst, 'plane-starter'), 409, /flying/);
  });

  it('rejects the fill-up when cash is below the cost with 409', async () => {
    const inst = await freshDb('refuel-poor.db');
    await inst.db.update(schema.planes).set({ fuel: 1_000 }).where(eq(schema.planes.id, 'plane-starter'));
    await inst.db.update(schema.account).set({ cash: 10 }); // cost is ~4960

    await expectActionError(refuelPlane(inst, 'plane-starter'), 409, /insufficient funds/i);
  });

  it('rejects an unknown id with 404', async () => {
    const inst = await freshDb('refuel-unknown.db');
    await expectActionError(refuelPlane(inst, 'ghost'), 404);
  });
});