import { content } from "@deadhead/content";
import { describe, expect, it } from "vitest";
import {
  boardPeriodMs,
  checkPilotEligibility,
  checkRoute,
  contractTripGameHours,
  generateContractBoard,
  isCompletable,
  type BoardInput,
  type Contract,
  type FleetMember,
} from "../src/index";

const earth = content.location("earth")!;
const discoveredIds = new Set(["earth", "moon", "mars"]);
const base: BoardInput = { location: earth, discoveredIds, periodIndex: 500, worldSeed: 777 };
const { config } = content;
const bands = config.contractMassBands;

/** Whether this crew can fly the contract (the sim's own route and pilot rules). */
function fits(contract: Contract, member: FleetMember): boolean {
  const model = content.shipModel(member.modelId)!;
  return (
    !contract.firstContact &&
    contract.massTonnes <= model.cargoCapacityTonnes &&
    checkRoute(model, earth, content.location(contract.destinationId)!, content.config).ok &&
    checkPilotEligibility(member.skills, contract).ok &&
    // Priority (CR-007): the ship must make the delivery window.
    (!contract.priority ||
      contractTripGameHours(model, contract, content) <= contract.deliveryWindowGameHours!)
  );
}

const floorOf = (band: { min: number }) =>
  band.min === Math.min(...bands.map((b) => b.min)) ? 0 : band.min;

const courier: FleetMember = { modelId: "courier", skills: {} };

describe("boards that fit the fleet (CR-006)", () => {
  it("gives an empty fleet an empty board: nobody could take anything (CR-019)", () => {
    expect(generateContractBoard({ ...base, fleet: [] }, content)).toEqual([]);
  });

  it("is deterministic with a fleet", () => {
    const input = { ...base, fleet: [courier] };
    expect(generateContractBoard(input, content)).toEqual(generateContractBoard(input, content));
  });

  it("gives a lone Courier a full board of jobs it can fly, with no previews (CR-019)", () => {
    for (let p = 0; p < 200; p++) {
      const board = generateContractBoard({ ...base, periodIndex: p, fleet: [courier] }, content);
      expect(board).toHaveLength(config.contractBoardSize);
      expect(board.every((c) => fits(c, courier))).toBe(true);
    }
  });

  it("offers skill cargo up to the pilot's level, never above", () => {
    const skilled: FleetMember = { modelId: "courier", skills: { "expensive-cargo": 3 } };
    let skillJobs = 0;
    for (let p = 0; p < 200; p++) {
      const board = generateContractBoard({ ...base, periodIndex: p, fleet: [skilled] }, content);
      for (const c of board.filter((c) => fits(c, skilled))) {
        if (c.requiredSkill) {
          skillJobs++;
          expect(c.requiredSkill.level).toBeLessThanOrEqual(3);
        }
      }
    }
    expect(skillJobs).toBeGreaterThan(0);
  });

  it("keeps the configured band counts when the fleet covers every band", () => {
    // Pilots skilled in everything, so no candidate is turned away (CR-019).
    const skills = Object.fromEntries(content.skills.map((k) => [k.id, k.maxLevel]));
    const fleet: FleetMember[] = ["courier", "freighter", "bulk-hauler"].map((modelId) => ({
      modelId,
      skills,
    }));
    const board = generateContractBoard({ ...base, fleet }, content);
    let slot = 0;
    for (const band of bands) {
      for (let k = 0; k < band.count; k++, slot++) {
        expect(board[slot]!.massTonnes).toBeGreaterThanOrEqual(floorOf(band));
        expect(board[slot]!.massTonnes).toBeLessThanOrEqual(band.max);
      }
    }
    for (const [i, band] of bands.entries()) {
      const inBand = board.filter((c) => c.massTonnes >= floorOf(band) && c.massTonnes <= band.max);
      // Every job is one this band's ship (or a bigger one) can take.
      expect(
        inBand.every((c) =>
          fleet.slice(i).some((m) => isCompletable(c, [m], discoveredIds, content)),
        ),
      ).toBe(true);
    }
  });

  it("expires fit jobs with the board period", () => {
    const end = (base.periodIndex + 1) * boardPeriodMs(config);
    for (const c of generateContractBoard({ ...base, fleet: [courier] }, content)) {
      expect(c.expiresAt).toBe(end);
    }
  });
});

describe("fit jobs carry varied goods (CR-008 fix)", () => {
  // The user's save: one Courier at the Moon, pilot Heavy Cargo 1 and Long Haul 1.
  const pilotCourier: FleetMember = {
    modelId: "courier",
    skills: { "heavy-cargo": 1, "long-haul": 1 },
  };
  const moonInput: BoardInput = {
    location: content.location("moon")!,
    discoveredIds: new Set(["earth", "moon"]),
    periodIndex: 0,
    worldSeed: 4242,
    fleet: [pilotCourier],
  };

  it("offers the Courier several goods it can really carry, not undersized Lunar Titanium", () => {
    let distinct = 0;
    for (let p = 0; p < 100; p++) {
      const board = generateContractBoard({ ...moonInput, periodIndex: p }, content);
      const flyable = board.filter((c) => fits(c, pilotCourier));
      expect(flyable.length).toBeGreaterThanOrEqual(5);
      for (const c of flyable) {
        const { min, max } = content.good(c.goodId)!.massTonnes;
        expect(c.massTonnes).toBeGreaterThanOrEqual(min);
        expect(c.massTonnes).toBeLessThanOrEqual(max);
        expect(c.goodId).not.toBe("lunar-titanium");
      }
      distinct += new Set(flyable.map((c) => c.goodId)).size;
    }
    expect(distinct / 100).toBeGreaterThanOrEqual(3);
  });
});