import { describe, it, expect } from 'vitest';
import { getEncodedToken, type Proof } from '@cashu/cashu-ts';
import {
  normalizeCashuPubkey,
  escrowLocktime,
  escrowP2PKOptions,
  secretPolicy,
  parseEscrowToken,
  createEscrowToken,
  type EscrowP2PKOptions,
  SECONDS_PER_DAY,
  ESCROW_MIN_LOCK_DAYS,
} from './cashuEscrow';

const SELLER_XONLY = 'ab'.repeat(32);
const SELLER = `02${SELLER_XONLY}`;
const BUYER = `02${'cd'.repeat(32)}`;

function toHex(text: string): string {
  return [...new TextEncoder().encode(text)]
    .map((b) => b.toString(16).padStart(2, '0'))
    .join('');
}

function p2pkSecret(overrides: Record<string, string> = {}): string {
  return toHex(
    JSON.stringify({
      nonce: '00'.repeat(8),
      data: SELLER,
      tags: [
        ['sigflag', 'SIG_INPUTS'],
        ['n_sigs', '1'],
        ['locktime', String(overrides.locktime ?? '4102444800')],
        ['refund', BUYER],
      ],
    }),
  );
}

function token(secret: string, amount: number): string {
  return getEncodedToken({
    mint: 'https://mint.example',
    unit: 'sat',
    proofs: [{ id: '009a1f293253e41e', amount, secret, C: `02${'00'.repeat(32)}` }],
  });
}

function lockedProofs(options: EscrowP2PKOptions, amount = 1000): Proof[] {
  const secret = toHex(
    JSON.stringify({
      nonce: '00'.repeat(8),
      data: options.pubkey,
      tags: [
        ['sigflag', 'SIG_INPUTS'],
        ['n_sigs', String(options.requiredSignatures)],
        ['locktime', String(options.locktime)],
        ['refund', ...options.refundKeys],
      ],
    }),
  );
  return [{ id: '009a1f293253e41e', amount, secret, C: `02${'00'.repeat(32)}` }];
}

describe('normalizeCashuPubkey', () => {
  it('prefixes 32-byte x-only keys with 02', () => {
    expect(normalizeCashuPubkey(SELLER_XONLY)).toBe(SELLER);
  });

  it('leaves compressed keys unchanged', () => {
    expect(normalizeCashuPubkey(SELLER)).toBe(SELLER);
  });

  it('rejects non-hex and wrong-length input', () => {
    expect(normalizeCashuPubkey('nope')).toBeNull();
    expect(normalizeCashuPubkey('1234')).toBeNull();
    expect(normalizeCashuPubkey(undefined)).toBeNull();
  });
});

describe('escrowLocktime', () => {
  it('adds the requested number of days', () => {
    const from = 1_000_000_000_000; // ms
    expect(escrowLocktime(3, from)).toBe(Math.floor(from / 1000) + 3 * SECONDS_PER_DAY);
  });

  it('enforces a minimum lock of one day', () => {
    const from = 0;
    expect(escrowLocktime(0, from)).toBe((from / 1000) + ESCROW_MIN_LOCK_DAYS * SECONDS_PER_DAY);
  });
});

describe('secretPolicy', () => {
  it('parses a P2PK secret into a policy', () => {
    const policy = secretPolicy(p2pkSecret());
    expect(policy?.pubkey).toBe(SELLER);
    expect(policy?.refundKeys).toContain(BUYER);
    expect(policy?.locktime).toBe(4102444800);
    expect(policy?.requiredSignatures).toBe(1);
  });

  it('returns null for non-locked secrets', () => {
    expect(secretPolicy('00'.repeat(32))).toBeNull();
    expect(secretPolicy(toHex('not json'))).toBeNull();
  });
});

describe('escrowP2PKOptions', () => {
  it('locks to the seller with the buyer as refund key', () => {
    const opts = escrowP2PKOptions({
      sellerPubkey: SELLER_XONLY,
      buyerPubkey: BUYER,
      lockDays: 3,
      from: 1_000_000_000_000,
    });
    expect(opts.pubkey).toBe(SELLER);
    expect(opts.refundKeys).toEqual([BUYER]);
    expect(opts.locktime).toBe(Math.floor(1_000_000_000_000 / 1000) + 3 * SECONDS_PER_DAY);
    expect(opts.requiredRefundSignatures).toBe(1);
  });

  it('rejects invalid keys', () => {
    expect(() => escrowP2PKOptions({ sellerPubkey: 'bad', buyerPubkey: BUYER })).toThrow();
    expect(() => escrowP2PKOptions({ sellerPubkey: SELLER, buyerPubkey: '' })).toThrow();
  });

  it('builds an optional seller+arbiter / buyer+arbiter 2-of-3 policy', () => {
    const arbiter = '02' + 'c'.repeat(64);
    const opts = escrowP2PKOptions({
      sellerPubkey: SELLER_XONLY,
      buyerPubkey: BUYER,
      arbiterPubkey: arbiter,
    });
    expect(opts.pubkey).toEqual([SELLER, arbiter]);
    expect(opts.refundKeys).toEqual([BUYER, arbiter]);
    expect(opts.requiredSignatures).toBe(2);
    expect(opts.requiredRefundSignatures).toBe(2);
  });

  it('rejects an arbiter that is also the buyer or seller', () => {
    expect(() =>
      escrowP2PKOptions({ sellerPubkey: SELLER, buyerPubkey: BUYER, arbiterPubkey: SELLER }),
    ).toThrow();
  });
});

describe('parseEscrowToken', () => {
  it('reads amount, mint and lock policy', () => {
    const info = parseEscrowToken(token(p2pkSecret(), 2100));
    expect(info.amount).toBe(2100);
    expect(info.mint).toBe('https://mint.example');
    expect(info.locked).toBe(true);
    expect(info.policy?.locktime).toBe(4102444800);
    expect(info.refundable).toBe(false);
  });

  it('marks past locktimes as refundable', () => {
    const info = parseEscrowToken(token(p2pkSecret({ locktime: '1' }), 21));
    expect(info.refundable).toBe(true);
  });

  it('treats a plain token as unlocked', () => {
    const plain = getEncodedToken({
      mint: 'https://mint.example',
      unit: 'sat',
      proofs: [{ id: '009a1f293253e41e', amount: 5, secret: '00'.repeat(32), C: `02${'00'.repeat(32)}` }],
    });
    const info = parseEscrowToken(plain);
    expect(info.locked).toBe(false);
    expect(info.refundable).toBe(false);
  });

  it('throws on a malformed token', () => {
    expect(() => parseEscrowToken('not-a-token')).toThrow();
  });
});

describe('createEscrowToken', () => {
  it('pays the invoice, mints locked proofs, and returns a parsable token', async () => {
    const paid: string[] = [];
    let seen: EscrowP2PKOptions | null = null;

    const wallet = {
      async createMintQuote(amount: number) {
        expect(amount).toBe(1000);
        return { quote: 'q1', request: 'lnbc1fake' };
      },
      async checkMintQuote() {
        return { state: 'PAID' };
      },
      async mintProofs(amount: number, quote: string, options: { p2pk: EscrowP2PKOptions }) {
        expect(amount).toBe(1000);
        expect(quote).toBe('q1');
        seen = options.p2pk;
        return lockedProofs(options.p2pk);
      },
    };

    const result = await createEscrowToken(
      { wallet, payInvoice: async (bolt11) => { paid.push(bolt11); }, pollMs: 0 },
      {
        mintUrl: 'https://mint.example',
        amountSats: 1000,
        sellerPubkey: SELLER_XONLY,
        buyerPubkey: BUYER,
        lockDays: 2,
      },
    );

    expect(paid).toEqual(['lnbc1fake']);
    expect(result.amount).toBe(1000);
    expect(seen).toMatchObject({ pubkey: SELLER, refundKeys: [BUYER] });

    const info = parseEscrowToken(result.token);
    expect(info.locked).toBe(true);
    expect(info.policy?.pubkey).toBe(SELLER);
    expect(info.policy?.refundKeys).toContain(BUYER);
    expect(info.refundable).toBe(false);
  });

  it('throws when the invoice is never paid (and never mints)', async () => {
    const wallet = {
      async createMintQuote() {
        return { quote: 'q', request: 'r' };
      },
      async checkMintQuote() {
        return { state: 'UNPAID' };
      },
      async mintProofs(): Promise<Proof[]> {
        throw new Error('should not mint');
      },
    };

    await expect(
      createEscrowToken(
        { wallet, payInvoice: async () => {}, maxWaitMs: 5, pollMs: 1 },
        { mintUrl: 'https://mint.example', amountSats: 10, sellerPubkey: SELLER, buyerPubkey: BUYER },
      ),
    ).rejects.toThrow(/never confirmed/);
  });
});