import { describe, it, expect, beforeEach } from "vitest";
import { bytesToHex } from "@hamradio/packet";
import { Identity, LocalIdentity, Contact, Group, Contacts, parseNodeHash } from "../src/identity";
import { PrivateKey, PublicKey, SharedSecret } from "../src/crypto";
import { DecryptedGroupText, DecryptedGroupData } from "../src/packet.types";

function randomBytes(len: number) {
  return Uint8Array.from({ length: len }, () => Math.floor(Math.random() * 256));
}

describe("parseNodeHash", () => {
  it("parses Uint8Array", () => {
    expect(parseNodeHash(Uint8Array.of(0x42))).toBe(0x42);
  });
  it("parses number", () => {
    expect(parseNodeHash(0x42)).toBe(0x42);
    expect(() => parseNodeHash(-1)).toThrow();
    expect(() => parseNodeHash(256)).toThrow();
  });
  it("parses string", () => {
    expect(parseNodeHash("2a")).toBe(0x2a);
    expect(() => parseNodeHash("2a2a")).toThrow();
  });
  it("throws on invalid type", () => {
    // @ts-expect-error testing invalid input
    expect(() => parseNodeHash({})).toThrow();
  });
});

describe("Identity", () => {
  let pub: Uint8Array;
  let identity: Identity;

  beforeEach(() => {
    pub = randomBytes(32);
    identity = new Identity(pub);
  });

  it("constructs from Uint8Array", () => {
    expect(identity.publicKey.toBytes()).toEqual(pub);
  });

  it("constructs from string", () => {
    const hex = bytesToHex(pub);
    const id = new Identity(hex);
    expect(id.publicKey.toBytes()).toEqual(pub);
  });

  it("hash returns NodeHash", () => {
    expect(typeof identity.hash()).toBe("number");
  });

  it("toString returns string", () => {
    expect(typeof identity.toString()).toBe("string");
  });

  it("verify delegates to publicKey", () => {
    const msg = randomBytes(10);
    const sig = randomBytes(64);
    expect(identity.verify(sig, msg)).toBe(identity.publicKey.verify(msg, sig));
  });

  it("matches works for various types", () => {
    expect(identity.matches(identity)).toBe(true);
    expect(identity.matches(identity.publicKey)).toBe(true);
    expect(identity.matches(identity.publicKey.toBytes())).toBe(true);
    expect(identity.matches(identity.publicKey.toString())).toBe(true);
    expect(identity.matches(randomBytes(32))).toBe(false);
  });

  /* eslint-disable  @typescript-eslint/no-explicit-any */
  it("constructor throws on invalid type", () => {
    expect(() => new (Identity as any)(123)).toThrow();
  });

  it("matches throws on invalid type", () => {
    const pub = randomBytes(32);
    const id = new Identity(pub);
    // @ts-expect-error testing wrong type
    expect(() => id.matches({})).toThrow();
  });
});

describe("LocalIdentity", () => {
  let priv: PrivateKey;
  let pub: PublicKey;
  let local: LocalIdentity;

  beforeEach(() => {
    priv = PrivateKey.generate();
    pub = priv.toPublicKey();
    local = new LocalIdentity(priv, pub);
  });

  it("constructs from PrivateKey and PublicKey", () => {
    expect(local.publicKey.toBytes()).toEqual(pub.toBytes());
  });

  it("constructs from Uint8Array and string", () => {
    const priv2 = PrivateKey.generate();
    const pub2 = priv2.toPublicKey();
    const local2 = new LocalIdentity(priv2.toBytes(), pub2.toString());
    expect(local2.publicKey.toBytes()).toEqual(pub2.toBytes());
  });

  it("signs message", () => {
    const msg = Uint8Array.from([1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12]);
    const sig = local.sign(msg);
    expect(sig).toBeInstanceOf(Uint8Array);
    expect(sig.length).toBeGreaterThan(0);
  });

  it("calculates shared secret with Identity", () => {
    const otherPriv = PrivateKey.generate();
    const other = new Identity(otherPriv.toPublicKey().toBytes());
    const secret = local.calculateSharedSecret(other);
    expect(secret).toBeInstanceOf(SharedSecret);
  });

  it("calculates shared secret with IPublicKey", () => {
    const otherPriv = PrivateKey.generate();
    const otherPub = otherPriv.toPublicKey();
    const secret = local.calculateSharedSecret(otherPub);
    expect(secret).toBeInstanceOf(SharedSecret);
  });

  it("calculateSharedSecret throws on invalid input", () => {
    const other: any = {};
    expect(() => local.calculateSharedSecret(other)).toThrow();
  });
});

describe("Contact", () => {
  let priv: PrivateKey;
  let pub: PublicKey;
  let identity: Identity;
  let contact: Contact;

  beforeEach(() => {
    priv = PrivateKey.generate();
    pub = priv.toPublicKey();
    identity = new Identity(pub.toBytes());
    contact = new Contact("Alice", identity);
  });

  it("constructs from Identity", () => {
    expect(contact.identity).toBe(identity);
    expect(contact.name).toBe("Alice");
  });

  /* eslint-disable  @typescript-eslint/no-explicit-any */
  it("constructor throws on invalid type", () => {
    expect(() => new (Contact as any)("X", 123)).toThrow();
  });

  it("constructs from Uint8Array", () => {
    const c = new Contact("Bob", pub.toBytes());
    expect(c.identity.publicKey.toBytes()).toEqual(pub.toBytes());
  });

  it("matches works", () => {
    expect(contact.matches(pub)).toBe(true);
    expect(contact.matches(pub.toBytes())).toBe(true);
    expect(contact.matches(new PublicKey(randomBytes(32)))).toBe(false);
  });

  it("publicKey returns PublicKey", () => {
    expect(contact.publicKey()).toBeInstanceOf(PublicKey);
  });

  it("calculateSharedSecret delegates", () => {
    const me = new LocalIdentity(priv, pub);
    const secret = contact.calculateSharedSecret(me);
    expect(secret).toBeInstanceOf(SharedSecret);
  });
});

describe("Group", () => {
  let group: Group;
  let secret: SharedSecret;
  let name: string;

  beforeEach(() => {
    name = "#test";
    secret = SharedSecret.fromName(name);
    group = new Group(name, secret);
  });

  it("constructs with and without secret", () => {
    const g1 = new Group(name, secret);
    expect(g1).toBeInstanceOf(Group);
    const g2 = new Group(name);
    expect(g2).toBeInstanceOf(Group);
  });

  it("hash returns NodeHash", () => {
    expect(typeof group.hash()).toBe("number");
  });

  it("encryptText and decryptText roundtrip", () => {
    const plain: DecryptedGroupText = {
      timestamp: new Date(),
      textType: 1,
      attempt: 2,
      message: "hello"
    };
    const { hmac, ciphertext } = group.encryptText(plain);
    const decrypted = group.decryptText(hmac, ciphertext);
    expect(decrypted.message).toBe(plain.message);
    expect(decrypted.textType).toBe(plain.textType);
    expect(decrypted.attempt).toBe(plain.attempt);
    expect(typeof decrypted.timestamp).toBe("object");
  });

  it("encryptData and decryptData roundtrip", () => {
    const plain: DecryptedGroupData = {
      timestamp: new Date(),
      data: randomBytes(10)
    };
    const { hmac, ciphertext } = group.encryptData(plain);
    const decrypted = group.decryptData(hmac, ciphertext);
    expect(decrypted.data).toEqual(plain.data);
    expect(typeof decrypted.timestamp).toBe("object");
  });

  it("decryptText throws on short ciphertext", () => {
    expect(() => group.decryptText(randomBytes(16), Uint8Array.of(1, 2, 3, 4))).toThrow();
  });

  it("decryptData throws on short ciphertext", () => {
    expect(() => group.decryptData(randomBytes(16), Uint8Array.of(1, 2, 3))).toThrow();
  });
});

describe("Contacts", () => {
  let contacts: Contacts;
  let local: LocalIdentity;
  let contact: Contact;
  let group: Group;

  beforeEach(() => {
    contacts = new Contacts();
    const priv = PrivateKey.generate();
    const pub = priv.toPublicKey();
    local = new LocalIdentity(priv, pub);
    contact = new Contact("Alice", pub.toBytes());
    group = new Group("Public");
  });

  it("addLocalIdentity and addContact", () => {
    contacts.addLocalIdentity(local);
    contacts.addContact(contact);
    // No error means success
  });

  it("addGroup", () => {
    contacts.addGroup(group);
  });

  it("decryptGroupText and decryptGroupData", () => {
    contacts.addGroup(group);
    const text: DecryptedGroupText = {
      timestamp: new Date(),
      textType: 1,
      attempt: 0,
      message: "hi"
    };
    const { hmac, ciphertext } = group.encryptText(text);
    const res = contacts.decryptGroupText(group.hash(), hmac, ciphertext);
    expect(res.decrypted.message).toBe(text.message);

    const data: DecryptedGroupData = {
      timestamp: new Date(),
      data: randomBytes(8)
    };
    const enc = group.encryptData(data);
    const res2 = contacts.decryptGroupData(group.hash(), enc.hmac, enc.ciphertext);
    expect(res2.decrypted.data).toEqual(data.data);
  });

  it("decryptGroupText throws on unknown group", () => {
    expect(() => contacts.decryptGroupText(0x99, randomBytes(16), randomBytes(16))).toThrow();
  });

  it("decryptGroupData throws on unknown group", () => {
    expect(() => contacts.decryptGroupData(0x99, randomBytes(16), randomBytes(16))).toThrow();
  });

  it("decrypt throws on unknown source/destination", () => {
    contacts.addLocalIdentity(local);
    expect(() => contacts.decrypt(0x99, 0x99, randomBytes(16), randomBytes(16))).toThrow();
  });

  it("decrypt throws on decryption failure", () => {
    contacts.addLocalIdentity(local);
    contacts.addContact(contact);
    expect(() =>
      contacts.decrypt(contact.identity.hash(), local.publicKey.key[0], randomBytes(16), randomBytes(16))
    ).toThrow();
  });

  it("decrypt works for valid shared secret", () => {
    // Setup two identities that can communicate
    const privA = PrivateKey.generate();
    const pubA = privA.toPublicKey();
    const localA = new LocalIdentity(privA, pubA);

    const privB = PrivateKey.generate();
    const pubB = privB.toPublicKey();
    const contactB = new Contact("Bob", pubB);

    contacts.addLocalIdentity(localA);
    contacts.addContact(contactB);

    // Encrypt a message using the shared secret
    const shared = localA.calculateSharedSecret(contactB.identity);
    const msg = Uint8Array.from([2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37]);
    const { hmac, ciphertext } = shared.encrypt(msg);

    const srcHash = contactB.identity.hash();
    const dstHash = localA.publicKey.key[0];

    const res = contacts.decrypt(srcHash, dstHash, hmac, ciphertext);
    expect(res.decrypted).toEqual(msg);
    expect(res.contact.name).toBe("Bob");
    expect(res.localIdentity.publicKey.toBytes()).toEqual(pubA.toBytes());
  });

  /* eslint-disable  @typescript-eslint/no-explicit-any */
  /* eslint-disable  @typescript-eslint/no-unused-vars */
  it("group decryption falls back when first group fails", () => {
    // Setup a group that will succeed and a fake one that throws
    const name = "#fallback";
    const real = new Group(name);
    contacts.addGroup(real);
    const hash = real.hash();
    const fake = {
      name,
      decryptText: (_h: Uint8Array, _c: Uint8Array) => {
        throw new Error("fail");
      }
    } as any;
    // Inject fake group before real one
    (contacts as any).groups[hash] = [fake, real];

    const text = { timestamp: new Date(), textType: 1, attempt: 0, message: "hi" } as DecryptedGroupText;
    const enc = real.encryptText(text);
    const res = contacts.decryptGroupText(hash, enc.hmac, enc.ciphertext);
    expect(res.decrypted.message).toBe(text.message);
    expect(res.group).toBe(real);
  });

  /* eslint-disable  @typescript-eslint/no-explicit-any */
  /* eslint-disable  @typescript-eslint/no-unused-vars */
  it("group data decryption falls back when first group fails", () => {
    const name = "#fallbackdata";
    const real = new Group(name);
    contacts.addGroup(real);
    const hash = real.hash();
    const fake = {
      name,
      decryptData: (_h: Uint8Array, _c: Uint8Array) => {
        throw new Error("fail");
      }
    } as any;
    (contacts as any).groups[hash] = [fake, real];

    const data = { timestamp: new Date(), data: randomBytes(8) } as DecryptedGroupData;
    const enc = real.encryptData(data);
    const res = contacts.decryptGroupData(hash, enc.hmac, enc.ciphertext);
    expect(res.decrypted.data).toEqual(data.data);
    expect(res.group).toBe(real);
  });

  it("decryptText throws when decrypted payload is too short", () => {
    const name = "#short";
    const secret = SharedSecret.fromName(name);
    const group = new Group(name, secret);
    // Create ciphertext that decrypts to a payload shorter than 5 bytes
    const small = new Uint8Array([1, 2, 3, 4]);
    const enc = secret.encrypt(small);
    expect(() => group.decryptText(enc.hmac, enc.ciphertext)).toThrow(/Invalid ciphertext/);
  });

  it("decryptData throws when decrypted payload is too short", () => {
    const name = "#shortdata";
    const secret = SharedSecret.fromName(name);
    const group = new Group(name, secret);
    const small = new Uint8Array([1, 2, 3]);
    const enc = secret.encrypt(small);
    expect(() => group.decryptData(enc.hmac, enc.ciphertext)).toThrow(/Invalid ciphertext/);
  });

  it("decrypt throws on unknown destination hash", () => {
    contacts.addContact(contact);
    expect(() => contacts.decrypt(contact.identity.hash(), 0x99, randomBytes(16), randomBytes(16))).toThrow(
      /Unknown destination hash/
    );
  });

  /* eslint-disable  @typescript-eslint/no-explicit-any */
  /* eslint-disable  @typescript-eslint/no-unused-vars */
  it("decryptGroupText throws when all groups fail", () => {
    const name = "#onlyfail";
    const group = new Group(name);
    const hash = group.hash();
    const fake = {
      decryptText: (_h: Uint8Array, _c: Uint8Array) => {
        throw new Error("fail");
      }
    } as any;
    (contacts as any).groups[hash] = [fake];
    expect(() => contacts.decryptGroupText(hash, randomBytes(16), randomBytes(16))).toThrow(
      /Decryption failed with all known groups/
    );
  });

  /* eslint-disable  @typescript-eslint/no-explicit-any */
  /* eslint-disable  @typescript-eslint/no-unused-vars */
  it("decryptGroupData throws when all groups fail", () => {
    const name = "#onlyfaildata";
    const group = new Group(name);
    const hash = group.hash();
    const fake = {
      decryptData: (_h: Uint8Array, _c: Uint8Array) => {
        throw new Error("fail");
      }
    } as any;
    (contacts as any).groups[hash] = [fake];
    expect(() => contacts.decryptGroupData(hash, randomBytes(16), randomBytes(16))).toThrow(
      /Decryption failed with all known groups/
    );
  });

  it("decrypt accepts PublicKey as source", () => {
    // Setup two identities that can communicate
    const privA = PrivateKey.generate();
    const pubA = privA.toPublicKey();
    const localA = new LocalIdentity(privA, pubA);

    const privB = PrivateKey.generate();
    const pubB = privB.toPublicKey();
    const contactB = new Contact("Bob", pubB);

    contacts.addLocalIdentity(localA);
    contacts.addContact(contactB);

    const shared = localA.calculateSharedSecret(contactB.identity);
    const msg = randomBytes(12);
    const { hmac, ciphertext } = shared.encrypt(msg);

    const res = contacts.decrypt(pubB, localA.publicKey.key[0], hmac, ciphertext);
    expect(res.decrypted).toEqual(msg);
    expect(res.contact.name).toBe("Bob");
  });

  it("decrypt with unknown PublicKey creates temporary contact and fails", () => {
    contacts.addLocalIdentity(local);
    const unknownPub = new PublicKey(randomBytes(32));
    expect(() => contacts.decrypt(unknownPub, local.publicKey.key[0], randomBytes(16), randomBytes(16))).toThrow();
  });

  it("LocalIdentity.calculateSharedSecret handles objects with publicKey variants", () => {
    const priv = PrivateKey.generate();
    const pub = priv.toPublicKey();
    const localId = new LocalIdentity(priv, pub);

    const s1 = localId.calculateSharedSecret(pub);
    expect(s1).toBeInstanceOf(SharedSecret);

    const obj2 = new Identity(pub.toBytes());
    const s2 = localId.calculateSharedSecret(obj2);
    expect(s2).toBeInstanceOf(SharedSecret);

    const obj3 = new Identity(pub);
    const s3 = localId.calculateSharedSecret(obj3);
    expect(s3).toBeInstanceOf(SharedSecret);
  });

  it("decrypt uses cached shared secret on repeated attempts", () => {
    // Setup two identities that can communicate
    const privA = PrivateKey.generate();
    const pubA = privA.toPublicKey();
    const localA = new LocalIdentity(privA, pubA);

    const privB = PrivateKey.generate();
    const pubB = privB.toPublicKey();
    const contactB = new Contact("Bob", pubB);

    contacts.addLocalIdentity(localA);
    contacts.addContact(contactB);

    const shared = localA.calculateSharedSecret(contactB.identity);
    const msg = randomBytes(12);
    const { hmac, ciphertext } = shared.encrypt(msg);

    const res1 = contacts.decrypt(contactB.identity.hash(), localA.publicKey.key[0], hmac, ciphertext);
    expect(res1.decrypted).toEqual(msg);

    // Second call should hit cached shared secret path
    const res2 = contacts.decrypt(contactB.identity.hash(), localA.publicKey.key[0], hmac, ciphertext);
    expect(res2.decrypted).toEqual(msg);
  });
});