import { describe, it, expect } from "vitest";
import { validateEntry, type ValidationContext } from "../validate.js";

const ctx: ValidationContext = {
  sourceLanguage: "es",
  pos: "noun",
  targetLanguages: ["en", "it", "de", "fr"],
  inputWords: new Set(["casa", "banco"]),
};

type Translation = {
  target_language: string;
  word: string;
  gender: string | null;
  difficulty: string;
};

const translations = (): Translation[] => [
  { target_language: "en", word: "house", gender: null, difficulty: "easy" },
  {
    target_language: "it",
    word: "casa",
    gender: "feminine",
    difficulty: "easy",
  },
  { target_language: "de", word: "Haus", gender: "neuter", difficulty: "easy" },
  {
    target_language: "fr",
    word: "maison",
    gender: "feminine",
    difficulty: "easy",
  },
];

const sense = (
  overrides: Record<string, unknown> = {},
): Record<string, unknown> => ({
  sense_index: 0,
  difficulty: "easy",
  definitions: ["Un edificio para vivir."],
  examples: ["Compraron una casa en la ciudad."],
  translations: translations(),
  ...overrides,
});

const entry = (
  overrides: Record<string, unknown> = {},
): Record<string, unknown> => ({
  headword: "casa",
  language: "es",
  pos: "noun",
  senses: [sense()],
  ...overrides,
});

const errorsOf = (raw: unknown): string[] => {
  const result = validateEntry(raw, ctx);
  return result.status === "invalid" ? result.errors : [];
};

describe("validateEntry", () => {
  it("accepts a fully valid entry", () => {
    const result = validateEntry(entry(), ctx);
    expect(result.status).toBe("valid");
  });

  it("treats senses: [] as empty (word skipped, not rejected)", () => {
    const result = validateEntry(entry({ senses: [] }), ctx);
    expect(result).toEqual({ status: "empty", headword: "casa" });
  });

  it("rejects senses: [] when the rest of the entry is invalid", () => {
    const result = validateEntry(entry({ senses: [], language: "en" }), ctx);
    expect(result.status).toBe("invalid");
  });

  it("rejects non-object input", () => {
    expect(validateEntry("casa", ctx).status).toBe("invalid");
    expect(validateEntry(null, ctx).status).toBe("invalid");
    expect(validateEntry([entry()], ctx).status).toBe("invalid");
  });

  it("rejects a headword that was not in the input batch", () => {
    expect(errorsOf(entry({ headword: "perro" }))).toContainEqual(
      expect.stringContaining("not in the input batch"),
    );
  });

  it("rejects a wrong source language", () => {
    expect(errorsOf(entry({ language: "en" }))).toContainEqual(
      expect.stringContaining('language must be "es"'),
    );
  });

  it("rejects a wrong pos", () => {
    expect(errorsOf(entry({ pos: "verb" }))).toContainEqual(
      expect.stringContaining('pos must be "noun"'),
    );
  });

  it("rejects more than 3 senses", () => {
    const senses = [0, 1, 2, 3].map((i) => sense({ sense_index: i }));
    expect(errorsOf(entry({ senses }))).toContainEqual(
      expect.stringContaining("at most 3"),
    );
  });

  it("rejects non-sequential sense_index", () => {
    const senses = [sense({ sense_index: 0 }), sense({ sense_index: 2 })];
    expect(errorsOf(entry({ senses }))).toContainEqual(
      expect.stringContaining("sense_index must be 1"),
    );
  });

  it("rejects an unknown difficulty", () => {
    expect(
      errorsOf(entry({ senses: [sense({ difficulty: "intermediate" })] })),
    ).toContainEqual(expect.stringContaining("difficulty must be one of"));
  });

  it("rejects empty definitions and examples", () => {
    expect(
      errorsOf(entry({ senses: [sense({ definitions: [] })] })),
    ).toContainEqual(
      expect.stringContaining("definitions must be a non-empty array"),
    );
    expect(
      errorsOf(entry({ senses: [sense({ examples: [""] })] })),
    ).toContainEqual(
      expect.stringContaining("examples must contain only non-empty strings"),
    );
  });

  it("rejects a non-null gender for English targets", () => {
    const bad = translations();
    bad[0] = {
      target_language: "en",
      word: "house",
      gender: "feminine",
      difficulty: "easy",
    };
    expect(
      errorsOf(entry({ senses: [sense({ translations: bad })] })),
    ).toContainEqual(
      expect.stringContaining('gender must be null for target "en"'),
    );
  });

  it("rejects a null gender for German targets", () => {
    const bad = translations();
    bad[2] = {
      target_language: "de",
      word: "Haus",
      gender: null,
      difficulty: "easy",
    };
    expect(
      errorsOf(entry({ senses: [sense({ translations: bad })] })),
    ).toContainEqual(expect.stringContaining('for target "de"'));
  });

  it("rejects neuter for Romance-language targets", () => {
    const bad = translations();
    bad[3] = {
      target_language: "fr",
      word: "maison",
      gender: "neuter",
      difficulty: "easy",
    };
    expect(
      errorsOf(entry({ senses: [sense({ translations: bad })] })),
    ).toContainEqual(expect.stringContaining('for target "fr"'));
  });

  it("rejects an invented gender value", () => {
    const bad = translations();
    bad[2] = {
      target_language: "de",
      word: "Haus",
      gender: "common",
      difficulty: "easy",
    };
    expect(
      errorsOf(entry({ senses: [sense({ translations: bad })] })).length,
    ).toBeGreaterThan(0);
  });

  it("rejects a missing target language", () => {
    const partial = translations().filter((t) => t.target_language !== "fr");
    expect(
      errorsOf(entry({ senses: [sense({ translations: partial })] })),
    ).toContainEqual(
      expect.stringContaining('missing translation for target language "fr"'),
    );
  });

  it("rejects the source language as a target", () => {
    const bad = [
      ...translations(),
      {
        target_language: "es",
        word: "hogar",
        gender: "masculine",
        difficulty: "easy",
      },
    ];
    expect(
      errorsOf(entry({ senses: [sense({ translations: bad })] })),
    ).toContainEqual(expect.stringContaining("target_language must be one of"));
  });

  it("rejects more than 2 translations for one target language", () => {
    const bad = [
      ...translations(),
      {
        target_language: "de",
        word: "Gebäude",
        gender: "neuter",
        difficulty: "medium",
      },
      {
        target_language: "de",
        word: "Heim",
        gender: "neuter",
        difficulty: "medium",
      },
    ];
    expect(
      errorsOf(entry({ senses: [sense({ translations: bad })] })),
    ).toContainEqual(
      expect.stringContaining(
        'more than 2 translations for target language "de"',
      ),
    );
  });

  it("rejects duplicate translation words for one target language", () => {
    const bad = [
      ...translations(),
      {
        target_language: "de",
        word: "Haus",
        gender: "neuter",
        difficulty: "medium",
      },
    ];
    expect(
      errorsOf(entry({ senses: [sense({ translations: bad })] })),
    ).toContainEqual(
      expect.stringContaining(
        'duplicate translation word for target language "de"',
      ),
    );
  });

  it("rejects a translation difficulty below the sense difficulty", () => {
    const easyTranslations = translations();
    expect(
      errorsOf(
        entry({
          senses: [
            sense({ difficulty: "medium", translations: easyTranslations }),
          ],
        }),
      ),
    ).toContainEqual(
      expect.stringContaining('is lower than sense difficulty "medium"'),
    );
  });

  it("allows a translation difficulty above the sense difficulty", () => {
    const harder = translations();
    harder[2] = {
      target_language: "de",
      word: "Geldinstitut",
      gender: "neuter",
      difficulty: "medium",
    };
    const result = validateEntry(
      entry({ senses: [sense({ translations: harder })] }),
      ctx,
    );
    expect(result.status).toBe("valid");
  });
});