import { describe, expect, it } from "vitest";
import { normalizeProgress } from "./progressNormalization";

const isGrade = (value: unknown): value is "correct" | "missed" =>
  value === "correct" || value === "missed";

function normalize(order: string[], currentIndex: number, liveIds: string[]) {
  return normalizeProgress({
    orderJson: JSON.stringify(order),
    currentIndex,
    dataJson: JSON.stringify({ a: "correct", deleted: "missed" }),
    liveIds,
    isValidValue: isGrade,
  });
}

describe("normalizeProgress", () => {
  it("preserves the logical current card when a prior card was deleted", () => {
    expect(normalize(["a", "b", "c"], 1, ["b", "c"]).currentIndex).toBe(0);
  });

  it("uses the next survivor when the current card was deleted", () => {
    expect(normalize(["a", "b", "c"], 1, ["a", "c"]).currentIndex).toBe(1);
  });

  it("uses the previous survivor when no later card remains", () => {
    expect(normalize(["a", "b", "c"], 2, ["a", "b"]).currentIndex).toBe(1);
  });

  it("preserves completed state after stale IDs are removed", () => {
    const result = normalize(["a", "b", "c"], 3, ["a", "c"]);
    expect(result.currentIndex).toBe(2);
    expect(result.completed).toBe(true);
  });

  it("recovers malformed JSON and filters stale result keys", () => {
    const result = normalizeProgress({
      orderJson: "not-json",
      currentIndex: -1,
      dataJson: '{"a":"correct","b":"invalid"}',
      liveIds: ["a", "b"],
      isValidValue: isGrade,
    });
    expect(result).toMatchObject({
      order: ["a", "b"],
      currentIndex: 0,
      data: { a: "correct" },
      completed: false,
      wasRecovered: true,
    });
  });

  it("returns a clear completed state when all saved cards were deleted", () => {
    const result = normalize(["deleted"], 0, []);
    expect(result).toMatchObject({ order: [], currentIndex: 0, completed: true });
  });

  it("lets content-specific validation reject a value owned by another item", () => {
    const result = normalizeProgress({
      orderJson: '["q1","q2"]',
      currentIndex: 0,
      dataJson: '{"q1":["q2-option"]}',
      liveIds: ["q1", "q2"],
      isValidValue: (value, id): value is string[] =>
        Array.isArray(value) && value.every((optionId) => optionId === `${id}-option`),
    });
    expect(result.data).toEqual({});
    expect(result.wasRecovered).toBe(true);
  });
});