src/lib/game/scoring.test.ts

import { describe, it, expect } from "vitest";
import { calculateScore, getStreakMultiplier, getSpeedBonus } from "./scoring";

describe("getStreakMultiplier", () => {
  it("returns 1.0 for streak 0-2", () => {
    expect(getStreakMultiplier(0)).toBe(1.0);
    expect(getStreakMultiplier(2)).toBe(1.0);
  });
  it("returns 1.5 for streak 3-4", () => {
    expect(getStreakMultiplier(3)).toBe(1.5);
    expect(getStreakMultiplier(4)).toBe(1.5);
  });
  it("returns 2.0 for streak 5-9", () => {
    expect(getStreakMultiplier(5)).toBe(2.0);
    expect(getStreakMultiplier(9)).toBe(2.0);
  });
  it("returns 3.0 for streak 10+", () => {
    expect(getStreakMultiplier(10)).toBe(3.0);
    expect(getStreakMultiplier(50)).toBe(3.0);
  });
});

describe("getSpeedBonus", () => {
  it("returns max bonus when most time remains", () => {
    expect(getSpeedBonus(9, 10)).toBeCloseTo(1.45, 1);
  });
  it("returns min bonus when no time remains", () => {
    expect(getSpeedBonus(0, 10)).toBe(1.0);
  });
  it("returns middle value at half time", () => {
    const bonus = getSpeedBonus(5, 10);
    expect(bonus).toBeGreaterThan(1.0);
    expect(bonus).toBeLessThan(1.5);
  });
});

describe("calculateScore", () => {
  it("scores easy question with no streak and no speed bonus", () => {
    expect(calculateScore("easy", 0, 0, 10)).toBe(100);
  });
  it("scores hard question with streak 10 and full speed", () => {
    const score = calculateScore("hard", 10, 9, 10);
    expect(score).toBe(Math.round(300 * 3.0 * (1.0 + 0.9 * 0.5)));
  });
  it("rounds to integer", () => {
    const score = calculateScore("medium", 3, 3, 10);
    expect(Number.isInteger(score)).toBe(true);
  });
});