import { readFileSync } from 'node:fs';
import { join } from 'node:path';
import { describe, expect, it } from 'vitest';
import { buildChains, matchKeys } from './cert-chain';
import { detectBlob } from './cert-model';
import type { AnyItem, CertItem, CsrItem, KeyItem } from './cert-types';

const fx = (name: string) => readFileSync(join(__dirname, '__fixtures__', name));

function load(...names: string[]): CertItem[] {
  const items: CertItem[] = [];
  names.forEach((name, file) => {
    const result = detectBlob(fx(name), { file, path: name, passwords: [] });
    for (const item of result.items) if (item.kind === 'certificate') items.push(item);
  });
  return items;
}

const cnOf = (certs: CertItem[], id: string) => certs.find((c) => c.id === id)?.cn;
const pathCns = (certs: CertItem[], path: string[]) => path.map((id) => cnOf(certs, id));

describe('buildChains', () => {
  it('Server + Zwischenzertifikat ohne Wurzel: unvollstaendig, Luecke nach der CA', () => {
    const certs = load('rsa-leaf.pem', 'rsa-inter.pem');
    const { chains } = buildChains(certs);
    expect(chains).toHaveLength(1);
    expect(pathCns(certs, chains[0].path)).toEqual(['www.example.test', 'Tessera Test Inter RSA']);
    expect(chains[0].complete).toBe(false);
    expect(chains[0].rootId).toBeNull();
    expect(chains[0].gap).toMatchObject({
      kind: 'afterCa',
      missingIssuerCn: 'Tessera Test Root RSA',
    });
  });

  it('mit Wurzel: vollstaendig, rootId gesetzt, keine Luecke', () => {
    const certs = load('rsa-leaf.pem', 'rsa-inter.pem', 'rsa-root.pem');
    const { chains } = buildChains(certs);
    expect(chains).toHaveLength(1);
    expect(chains[0].complete).toBe(true);
    expect(cnOf(certs, chains[0].rootId as string)).toBe('Tessera Test Root RSA');
    expect(chains[0].gap).toBeNull();
    expect(chains[0].path).toHaveLength(3);
  });

  it('nur das Serverzertifikat: Luecke nach dem Server mit Adresse des Ausstellers', () => {
    const certs = load('rsa-leaf.pem');
    const { chains } = buildChains(certs);
    expect(chains[0].gap).toMatchObject({
      kind: 'afterLeaf',
      missingIssuerCn: 'Tessera Test Inter RSA',
      aiaUrls: ['http://pki.example.test/rsa-inter.cer'],
    });
  });

  it('gleichnamige CA mit anderem Schluessel (Attrappe) wird nie genommen', () => {
    const certs = load(
      'rsa-leaf-noaki.pem',
      'rsa-inter-decoy.pem',
      'rsa-inter.pem',
      'rsa-root.pem',
    );
    const { chains } = buildChains(certs);
    expect(chains).toHaveLength(1);
    const names = chains[0].path.map((id) => certs.find((c) => c.id === id));
    expect(names[1]?.sources[0].path).toBe('rsa-inter.pem');
    expect(chains[0].complete).toBe(true);
  });

  it('nur die Attrappe vorhanden: die Signaturpruefung lehnt sie ab, Luecke nach dem Server', () => {
    const certs = load('rsa-leaf-noaki.pem', 'rsa-inter-decoy.pem', 'rsa-root.pem');
    const { chains } = buildChains(certs);
    expect(chains).toHaveLength(1);
    expect(chains[0].path).toHaveLength(1);
    expect(chains[0].gap?.kind).toBe('afterLeaf');
  });

  it('kreuzsigniertes Zwischenzertifikat fuehrt zur zweiten Wurzel', () => {
    const certs = load('rsa-leaf.pem', 'rsa-inter-cross.pem', 'rsa-root2.pem');
    const { chains } = buildChains(certs);
    expect(chains[0].complete).toBe(true);
    expect(cnOf(certs, chains[0].rootId as string)).toBe('Tessera Test Root RSA 2');
  });

  it('beide Varianten vorhanden: Hauptkette ueber rsa-inter und rsa-root, mindestens eine Alternative', () => {
    const certs = load('rsa-leaf.pem', 'rsa-inter.pem', 'rsa-inter-cross.pem', 'rsa-root.pem');
    const { chains } = buildChains(certs);
    expect(chains).toHaveLength(1);
    expect(chains[0].complete).toBe(true);
    expect(cnOf(certs, chains[0].rootId as string)).toBe('Tessera Test Root RSA');
    expect(chains[0].alternatives).toBeGreaterThanOrEqual(1);
  });

  it('abgelaufenes Zwischenzertifikat wird nicht als Hauptkette genommen', () => {
    const certs = load('rsa-leaf.pem', 'rsa-inter-expired.pem', 'rsa-inter.pem', 'rsa-root.pem');
    const { chains } = buildChains(certs);
    const middle = certs.find((c) => c.id === chains[0].path[1]);
    expect(middle?.isExpired).toBe(false);
    expect(middle?.sources[0].path).toBe('rsa-inter.pem');
    expect(chains[0].alternatives).toBeGreaterThanOrEqual(1);
  });

  it('die Reihenfolge der Eingabe aendert die Hauptkette nicht', () => {
    const names = ['rsa-leaf.pem', 'rsa-inter-expired.pem', 'rsa-inter.pem', 'rsa-root.pem'];
    const forward = load(...names);
    const reversed = load(...[...names].reverse());
    const a = buildChains(forward).chains[0];
    const b = buildChains(reversed).chains[0];
    expect(a.path).toEqual(b.path);
    expect(a.alternatives).toBe(b.alternatives);
  });

  it('Zwischenzertifikat + Wurzel ohne Serverzertifikat: eine Kette mit dem Zwischenzertifikat als Kopf', () => {
    const certs = load('rsa-inter.pem', 'rsa-root.pem');
    const { chains } = buildChains(certs);
    expect(chains).toHaveLength(1);
    expect(cnOf(certs, chains[0].headId)).toBe('Tessera Test Inter RSA');
    expect(chains[0].complete).toBe(true);
  });

  it('selbstsigniertes Serverzertifikat: Kette aus ihm selbst, vollstaendig, ohne Wurzel', () => {
    const certs = load('selfsigned-leaf.pem');
    const { chains } = buildChains(certs);
    expect(chains[0].path).toEqual([certs[0].id]);
    expect(chains[0].complete).toBe(true);
    expect(chains[0].rootId).toBeNull();
    expect(chains[0].gap).toBeNull();
  });

  it('EC-Kette wird genauso gebaut', () => {
    const certs = load('ec-leaf.pem', 'ec-inter.pem', 'ec-root.pem');
    const { chains } = buildChains(certs);
    expect(pathCns(certs, chains[0].path)).toEqual([
      'ec.example.test',
      'Tessera Test Inter EC',
      'Tessera Test Root EC',
    ]);
    expect(chains[0].complete).toBe(true);
  });

  it('mit vorgegebenem Kopf wird genau diese Kette gebaut', () => {
    const certs = load('rsa-leaf.pem', 'rsa-inter.pem', 'rsa-root.pem');
    const inter = certs.find((c) => c.role === 'intermediate') as CertItem;
    const { chains } = buildChains(certs, [inter.id]);
    expect(chains).toHaveLength(1);
    expect(chains[0].headId).toBe(inter.id);
  });

  it('leere Menge ergibt keine Ketten', () => {
    expect(buildChains([])).toEqual({ chains: [] });
  });
});

describe('matchKeys', () => {
  const PASSWORD = 'Test-Pass-123';
  function all(...names: [string, string?][]): AnyItem[] {
    const items: AnyItem[] = [];
    names.forEach(([name, password], file) => {
      const result = detectBlob(fx(name), {
        file,
        path: name,
        passwords: password ? [password] : [],
        ownPassword: password ?? '',
      });
      items.push(...result.items);
    });
    return items;
  }
  const certsOf = (items: AnyItem[]) =>
    items.filter((i): i is CertItem => i.kind === 'certificate');
  const keysOf = (items: AnyItem[]) => items.filter((i): i is KeyItem => i.kind === 'privateKey');
  const csrsOf = (items: AnyItem[]) => items.filter((i): i is CsrItem => i.kind === 'csr');

  it('ordnet Schluessel und Anfrage dem Serverzertifikat zu (RSA und EC)', () => {
    const items = all(
      ['rsa-leaf.pem'],
      ['rsa-leaf-key-enc-trad.pem', PASSWORD],
      ['rsa-leaf.csr'],
      ['ec-leaf.pem'],
      ['ec-leaf-key-sec1.der'],
      ['ec-leaf.csr.der'],
    );
    matchKeys(certsOf(items), keysOf(items), csrsOf(items));
    const certs = certsOf(items);
    const rsa = certs.find((c) => c.cn === 'www.example.test') as CertItem;
    const ec = certs.find((c) => c.cn === 'ec.example.test') as CertItem;
    const rsaKey = keysOf(items).find((k) => k.keyType === 'RSA') as KeyItem;
    const ecKey = keysOf(items).find((k) => k.keyType === 'EC') as KeyItem;
    const rsaCsr = csrsOf(items).find((r) => r.keyType === 'RSA') as CsrItem;
    const ecCsr = csrsOf(items).find((r) => r.keyType === 'EC') as CsrItem;
    expect(rsa.keyId).toBe(rsaKey.id);
    expect(rsaKey.certIds).toEqual([rsa.id]);
    expect(rsa.csrIds).toEqual([rsaCsr.id]);
    expect(rsaCsr.keyId).toBe(rsaKey.id);
    expect(rsaCsr.certIds).toEqual([rsa.id]);
    expect(ec.keyId).toBe(ecKey.id);
    expect(ecKey.certIds).toEqual([ec.id]);
    expect(ecCsr.keyId).toBe(ecKey.id);
    expect(ecCsr.certIds).toEqual([ec.id]);
  });

  it('ein fremder Schluessel gehoert zu keinem Zertifikat', () => {
    const items = all(['rsa-leaf.pem'], ['ec-leaf-key.pem']);
    matchKeys(certsOf(items), keysOf(items), csrsOf(items));
    expect(certsOf(items)[0].keyId).toBeNull();
    expect(keysOf(items)[0].certIds).toEqual([]);
  });

  it('Anfrage ohne Zertifikat und ohne Schluessel bleibt ohne Zuordnung', () => {
    const items = all(['ec-leaf.csr']);
    matchKeys(certsOf(items), keysOf(items), csrsOf(items));
    expect(csrsOf(items)[0].keyId).toBeNull();
    expect(csrsOf(items)[0].certIds).toEqual([]);
  });

  it('Zwischenzertifikat und Wurzel bekommen nie einen Schluessel, die Zuordnung ist wiederholbar', () => {
    const items = all(['rsa-leaf.pem'], ['rsa-inter.pem'], ['rsa-leaf-key.pem']);
    matchKeys(certsOf(items), keysOf(items), csrsOf(items));
    matchKeys(certsOf(items), keysOf(items), csrsOf(items));
    const withKey = certsOf(items).filter((c) => c.keyId !== null);
    expect(withKey.map((c) => c.cn)).toEqual(['www.example.test']);
    expect(keysOf(items)[0].certIds).toHaveLength(1);
  });
});