/**
 * Phase 6.3 — Surface catalog validation and lifecycle tests.
 *
 * Covers Contract 5.3 §§31.2-31.5 normative validation order, host state
 * lifecycle, registry refresh behavior, and the host's protocol-level
 * ability to negotiate with a genuine Contract 5.2 peer (Contract §28.2).
 * That is a property of NGN's own negotiation logic against whatever a peer
 * reports, using synthetic peer fixtures below -- distinct from, and not an
 * argument for, keeping any of this repository's own maintained reference
 * exhibits pinned to Contract 5.2. No exhibit-specific IDs appear in this
 * file.
 */
import test from 'node:test';
import assert from 'node:assert/strict';
import { validateSurfaceCatalog, validateCatalog } from '../src/validation.js';
import { ExhibitHost } from '../src/host.js';

/* ------------------------------------------------------------------ *
 * Helpers
 * ------------------------------------------------------------------ */

/** Minimal valid surface descriptor; caller may override fields. */
function validSurface(overrides = {}) {
  return {
    id: 'surface.primary-view',
    label: 'Primary View',
    kind: 'surface',
    primary: true,
    url: 'primary.html',
    ...overrides,
  };
}

/** Run validateSurfaceCatalog, capturing diagnostics. */
function validate(surfaces) {
  const diags = [];
  const result = validateSurfaceCatalog({ surfaces }, msg => diags.push(msg));
  return { result, diags };
}

/* ------------------------------------------------------------------ *
 * Absent / empty array forms (Contract 5.3 §31.3 forms 1 & 2)
 * ------------------------------------------------------------------ */

test('absent surfaces field is accepted and treated as empty', () => {
  const { result, diags } = validate(undefined);
  assert.deepEqual(result, []);
  assert.equal(diags.length, 0);
});

test('surfaces: [] is accepted and treated identically to absent', () => {
  const { result, diags } = validate([]);
  assert.deepEqual(result, []);
  assert.equal(diags.length, 0);
});

test('non-array surfaces field treated as absent', () => {
  const { result } = validate('not-an-array');
  assert.deepEqual(result, []);
});

/* ------------------------------------------------------------------ *
 * Individual entry validation — required fields (§31.2)
 * ------------------------------------------------------------------ */

test('valid single-entry catalog (one primary) is accepted', () => {
  const { result } = validate([validSurface()]);
  assert.equal(result.length, 1);
  assert.equal(result[0].id, 'surface.primary-view');
});

test('entry missing id is discarded', () => {
  const s = validSurface(); delete s.id;
  const { result, diags } = validate([s]);
  assert.deepEqual(result, []);
  assert.ok(diags.some(d => /Discarded/.test(d)));
});

test('entry with non-string id is discarded', () => {
  const { result } = validate([validSurface({ id: 42 })]);
  assert.deepEqual(result, []);
});

test('bare single-segment id (no dot) is discarded', () => {
  const { result, diags } = validate([validSurface({ id: 'nodot' })]);
  assert.deepEqual(result, []);
  assert.ok(diags.some(d => /Discarded/.test(d)));
});

test('id with uppercase is discarded', () => {
  const { result } = validate([validSurface({ id: 'Surface.control' })]);
  assert.deepEqual(result, []);
});

test('id with leading digit is discarded', () => {
  const { result } = validate([validSurface({ id: '1surface.control' })]);
  assert.deepEqual(result, []);
});

test('id with empty segment is discarded', () => {
  const { result } = validate([validSurface({ id: 'surface..control' })]);
  assert.deepEqual(result, []);
});

test('id with underscore is discarded', () => {
  const { result } = validate([validSurface({ id: 'surface_x.control' })]);
  assert.deepEqual(result, []);
});

test('entry missing label is discarded', () => {
  const s = validSurface(); delete s.label;
  const { result, diags } = validate([s]);
  assert.deepEqual(result, []);
  assert.ok(diags.some(d => /label/.test(d)));
});

test('entry with empty string label is discarded', () => {
  const { result } = validate([validSurface({ label: '' })]);
  assert.deepEqual(result, []);
});

test('entry with non-string label is discarded', () => {
  const { result } = validate([validSurface({ label: 123 })]);
  assert.deepEqual(result, []);
});

test('entry with wrong kind is discarded', () => {
  const { result, diags } = validate([validSurface({ kind: 'state' })]);
  assert.deepEqual(result, []);
  assert.ok(diags.some(d => /kind/.test(d)));
});

test('entry with kind impulse is discarded', () => {
  const { result } = validate([validSurface({ kind: 'impulse' })]);
  assert.deepEqual(result, []);
});

test('entry missing kind is discarded', () => {
  const s = validSurface(); delete s.kind;
  const { result } = validate([s]);
  assert.deepEqual(result, []);
});

test('entry with non-boolean primary (string) is discarded', () => {
  const { result, diags } = validate([validSurface({ primary: 'true' })]);
  assert.deepEqual(result, []);
  assert.ok(diags.some(d => /primary/.test(d)));
});

test('entry with primary: 1 (number) is discarded', () => {
  const { result } = validate([validSurface({ primary: 1 })]);
  assert.deepEqual(result, []);
});

test('entry with primary: null is discarded', () => {
  const { result } = validate([validSurface({ primary: null })]);
  assert.deepEqual(result, []);
});

test('entry missing url is discarded', () => {
  const s = validSurface(); delete s.url;
  const { result, diags } = validate([s]);
  assert.deepEqual(result, []);
  assert.ok(diags.some(d => /url/.test(d)));
});

test('absolute url is rejected as individually-invalid', () => {
  const { result, diags } = validate([validSurface({ url: 'https://evil.example/page.html' })]);
  assert.deepEqual(result, []);
  assert.ok(diags.some(d => /url/.test(d)));
});

test('protocol-relative url is rejected as individually-invalid', () => {
  const { result, diags } = validate([validSurface({ url: '//evil.example/page.html' })]);
  assert.deepEqual(result, []);
  assert.ok(diags.some(d => /url/.test(d)));
});

test('url with scheme (http:) is rejected', () => {
  const { result } = validate([validSurface({ url: 'http:page.html' })]);
  assert.deepEqual(result, []);
});

test('relative path url is accepted', () => {
  const { result } = validate([validSurface({ url: 'views/primary.html' })]);
  assert.equal(result.length, 1);
});

test('relative path with query string is accepted', () => {
  const { result } = validate([validSurface({ url: 'primary.html?surface=main' })]);
  assert.equal(result.length, 1);
});

test('bare query string is accepted (single-page exhibit)', () => {
  const { result } = validate([validSurface({ url: '?surface=main' })]);
  assert.equal(result.length, 1);
});

test('fragment-only url is accepted', () => {
  const { result } = validate([validSurface({ url: '#surface-main' })]);
  assert.equal(result.length, 1);
});

/* ------------------------------------------------------------------ *
 * §31.4 same-origin resolution with exhibitBaseUrl
 * ------------------------------------------------------------------ */

/** validateSurfaceCatalog with base URL supplied. */
function validateWithBase(surfaces, exhibitBaseUrl) {
  const diags = [];
  const result = validateSurfaceCatalog({ surfaces }, exhibitBaseUrl, msg => diags.push(msg));
  return { result, diags };
}

test('§31.4: relative url resolves same-origin — accepted', () => {
  const { result } = validateWithBase(
    [validSurface({ url: 'primary.html' })],
    'http://127.0.0.1:4173/test-fixtures/reference-exhibits/gallery/control.html'
  );
  assert.equal(result.length, 1);
});

test('§31.4: relative url that resolves to same origin with subdirectory — accepted', () => {
  const { result } = validateWithBase(
    [validSurface({ url: '../other/view.html' })],
    'http://127.0.0.1:4173/test-fixtures/exhibit/index.html'
  );
  assert.equal(result.length, 1);
});

test('§31.4: bare query string resolves same-origin — accepted', () => {
  const { result } = validateWithBase(
    [validSurface({ url: '?view=artifact' })],
    'http://127.0.0.1:4173/test-fixtures/exhibit/index.html'
  );
  assert.equal(result.length, 1);
});

test('§31.4: relative url that resolves cross-origin is rejected as individually-invalid', () => {
  // This cannot happen with a purely relative URL in practice, but a URL like
  // '//evil.example/x' would already be caught by structural form check.
  // To test cross-origin resolution we need a contrived exhibitBaseUrl on a different port.
  // An absolute URL with a scheme is already blocked by isRelativeSurfaceUrl; here we
  // verify that a structural-form-valid relative path resolving cross-origin is caught.
  // We pass a data: URL as base, which will fail to resolve and produce a diagnostic.
  const { result, diags } = validateWithBase(
    [validSurface({ url: 'primary.html', primary: true })],
    'data:text/html,<p>not-a-real-origin</p>'
  );
  // data: scheme — resolved URL will not be same-origin with data: base
  assert.deepEqual(result, []);
  assert.ok(diags.some(d => /Discarded/.test(d)));
});

test('§31.4: no exhibitBaseUrl — structural form only, relative url accepted without resolution', () => {
  // When no base URL is supplied (e.g. test-only contexts), structural check only.
  const { result } = validate([validSurface({ url: 'primary.html' })]);
  assert.equal(result.length, 1);
});


test('individually-invalid primary discarded; remaining valid primary => catalog valid', () => {
  const entries = [
    validSurface({ id: 'INVALID_ID', primary: true }),
    validSurface({ id: 'surface.secondary', label: 'Secondary', primary: true, url: 'secondary.html' }),
  ];
  const { result } = validate(entries);
  assert.equal(result.length, 1);
  assert.equal(result[0].id, 'surface.secondary');
});

test('individually-invalid primary discarded; zero valid primaries => whole catalog fallback', () => {
  const entries = [
    validSurface({ id: 'BAD', primary: true }),
    validSurface({ id: 'surface.secondary', label: 'Secondary', primary: false, url: 'secondary.html' }),
  ];
  const { result, diags } = validate(entries);
  assert.deepEqual(result, []);
  assert.ok(diags.some(d => /SURFACE_CATALOG_REJECTED/.test(d) || /exactly one/.test(d)));
});

test('zero primaries among valid entries => whole catalog rejected', () => {
  const entries = [
    validSurface({ id: 'surface.a', label: 'A', primary: false, url: 'a.html' }),
    validSurface({ id: 'surface.b', label: 'B', primary: false, url: 'b.html' }),
  ];
  const { result, diags } = validate(entries);
  assert.deepEqual(result, []);
  assert.ok(diags.some(d => /SURFACE_CATALOG_REJECTED/.test(d) || /exactly one/.test(d)));
});

test('multiple valid primaries => whole catalog rejected', () => {
  const entries = [
    validSurface({ id: 'surface.a', label: 'A', primary: true, url: 'a.html' }),
    validSurface({ id: 'surface.b', label: 'B', primary: true, url: 'b.html' }),
  ];
  const { result, diags } = validate(entries);
  assert.deepEqual(result, []);
  assert.ok(diags.some(d => /SURFACE_CATALOG_REJECTED/.test(d) || /exactly one/.test(d)));
});

test('all entries individually invalid => absent-equivalent, not malformed-primary', () => {
  const entries = [
    { id: 'BAD ID', label: 'x', kind: 'surface', primary: true, url: 'x.html' },
    { id: 'surface.y', label: '', kind: 'surface', primary: true, url: 'y.html' },
  ];
  const { result, diags } = validate(entries);
  assert.deepEqual(result, []);
  assert.ok(!diags.some(d => /SURFACE_CATALOG_REJECTED/.test(d)), 'empty valid set is absent-equivalent, not a primary violation');
});

test('non-empty valid catalog with one primary is fully returned', () => {
  const entries = [
    validSurface({ id: 'surface.ctrl', label: 'Control', primary: true, url: 'ctrl.html' }),
    validSurface({ id: 'surface.display', label: 'Display', primary: false, url: 'display.html' }),
    validSurface({ id: 'surface.info', label: 'Info', primary: false, url: 'info.html' }),
  ];
  const { result } = validate(entries);
  assert.equal(result.length, 3);
  assert.equal(result.filter(s => s.primary).length, 1);
});

/* ------------------------------------------------------------------ *
 * Optional fields preserved generically (§31.2)
 * ------------------------------------------------------------------ */

test('optional fields are preserved in validated descriptors', () => {
  const s = validSurface({
    description: 'The operator control surface.',
    role: 'control',
    aspectRatio: '16:9',
    category: 'operator',
    requires: ['render'],
  });
  const { result } = validate([s]);
  assert.equal(result.length, 1);
  assert.equal(result[0].description, 'The operator control surface.');
  assert.equal(result[0].role, 'control');
  assert.equal(result[0].aspectRatio, '16:9');
  assert.equal(result[0].category, 'operator');
  assert.deepEqual(result[0].requires, ['render']);
});

/* ------------------------------------------------------------------ *
 * Duplicate id handling
 * ------------------------------------------------------------------ */

test('duplicate id: second entry with same id is discarded', () => {
  const entries = [
    validSurface({ id: 'surface.ctrl', label: 'First', primary: true, url: 'ctrl.html' }),
    validSurface({ id: 'surface.ctrl', label: 'Duplicate', primary: false, url: 'ctrl2.html' }),
  ];
  const { result, diags } = validate(entries);
  assert.equal(result.length, 1);
  assert.equal(result[0].label, 'First');
  assert.ok(diags.some(d => /duplicate/.test(d)));
});

/* ------------------------------------------------------------------ *
 * Malformed surfaces do NOT invalidate targets/capabilities
 * ------------------------------------------------------------------ */

test('malformed surfaces field does not throw and does not affect validateCatalog', () => {
  const message = {
    exhibit: {}, contract: { major: 5 },
    registryRevision: 0, stateRevision: 0,
    capabilities: [],
    targets: [{ id: 'sample.level', kind: 'state', valueType: 'boolean', readable: true, writable: true, requires: [] }],
    surfaces: [{ id: 'BAD', label: '', kind: 'not-surface', primary: 'yes', url: 'https://evil.example' }],
  };
  assert.doesNotThrow(() => validateCatalog(message));
  const { result } = validate(message.surfaces);
  assert.deepEqual(result, []);
});

/* ------------------------------------------------------------------ *
 * ExhibitHost lifecycle — surfaces cleared on disconnect, refreshed on
 * registry.changed  (Parts 3 & 4)
 * ------------------------------------------------------------------ */

function peer53() {
  let receive, session = 0, sequence = 0;
  let currentSurfaces = [
    { id: 'surface.primary', label: 'Primary', kind: 'surface', primary: true, url: 'primary.html' },
    { id: 'surface.secondary', label: 'Secondary', kind: 'surface', primary: false, url: 'secondary.html' },
  ];
  const fixture = {
    transport: {
      subscribe(fn) { receive = fn; return () => {}; },
      close() {},
      send(m) {
        const out = { xzbt: '5.3', requestId: m.requestId, sessionId: `s${session}` };
        if (m.type === 'hello') {
          session++; sequence = 0;
          receive({ ...out, type: 'hello.result', sessionId: `s${session}`, contract: { major: 5, minor: 3 }, exhibit: { product: 'Synthetic 5.3 peer' } });
        } else if (m.type === 'describe') {
          receive({ ...out, type: 'describe.result', exhibit: { product: 'Synthetic 5.3 peer' },
            contract: { major: 5, minor: 3 }, targets: [{ id: 'sample.state', kind: 'state', valueType: 'boolean',
            readable: true, writable: true, requires: [] }], capabilities: [],
            registryRevision: 1, stateRevision: 0, surfaces: currentSurfaces });
        } else if (m.type === 'state.get') {
          receive({ ...out, type: 'state.result', stateRevision: 0, values: { 'sample.state': true } });
        }
      }
    },
    event(type, payload = {}) {
      receive({ xzbt: '5.3', type, sessionId: `s${session}`, sequence: ++sequence, timestamp: Date.now(), ...payload });
    },
    setSurfaces(list) { currentSurfaces = list; }
  };
  return fixture;
}

function peer52() {
  let receive, session = 0;
  const fixture = {
    transport: {
      subscribe(fn) { receive = fn; return () => {}; },
      close() {},
      send(m) {
        const out = { xzbt: '5.2', requestId: m.requestId, sessionId: `s${session}` };
        if (m.type === 'hello') {
          session++;
          receive({ ...out, type: 'hello.result', sessionId: `s${session}`, contract: { major: 5, minor: 2 }, exhibit: { product: 'Synthetic 5.2 peer' } });
        } else if (m.type === 'describe') {
          receive({ ...out, type: 'describe.result', exhibit: { product: 'Synthetic 5.2 peer' },
            contract: { major: 5, minor: 2 }, targets: [{ id: 'sample.state', kind: 'state', valueType: 'boolean',
            readable: true, writable: true, requires: [] }], capabilities: [],
            registryRevision: 1, stateRevision: 0 });
        } else if (m.type === 'state.get') {
          receive({ ...out, type: 'state.result', stateRevision: 0, values: { 'sample.state': true } });
        }
      }
    }
  };
  return fixture;
}

const settle = () => new Promise(resolve => setTimeout(resolve, 25));

test('Contract 5.3 exhibit: surfaces discovered after connect', async t => {
  const fixture = peer53();
  const host = new ExhibitHost({ debounceMs: 5, timeoutMs: 200 });
  t.after(() => host.disconnect());
  await host.connect(fixture.transport);
  assert.equal(host.contractMinor, 3);
  assert.equal(host.surfaces.length, 2);
  assert.equal(host.surfaces.filter(s => s.primary).length, 1);
  assert.equal(host.surfaces[0].id, 'surface.primary');
});

test('disconnect clears surface catalog', async t => {
  const fixture = peer53();
  const host = new ExhibitHost({ debounceMs: 5, timeoutMs: 200 });
  t.after(() => host.disconnect());
  await host.connect(fixture.transport);
  assert.equal(host.surfaces.length, 2);
  host.disconnect();
  assert.equal(host.surfaces.length, 0, 'surfaces must be empty after disconnect');
});

test('reconnect after disconnect rediscovers surface catalog', async t => {
  const fixture = peer53();
  const host = new ExhibitHost({ debounceMs: 5, timeoutMs: 200 });
  t.after(() => host.disconnect());
  await host.connect(fixture.transport);
  assert.equal(host.surfaces.length, 2);
  host.disconnect();
  assert.equal(host.surfaces.length, 0);
  await host.connect(fixture.transport);
  assert.equal(host.surfaces.length, 2, 'surfaces restored after reconnect');
});

test('registry.changed refreshes surface catalog when it changes', async t => {
  const fixture = peer53();
  const host = new ExhibitHost({ debounceMs: 5, timeoutMs: 200 });
  t.after(() => host.disconnect());
  await host.connect(fixture.transport);
  assert.equal(host.surfaces.length, 2);

  fixture.setSurfaces([
    { id: 'surface.primary', label: 'Primary Updated', kind: 'surface', primary: true, url: 'primary.html' }
  ]);
  fixture.event('registry.changed');
  await settle();

  assert.equal(host.surfaces.length, 1);
  assert.equal(host.surfaces[0].label, 'Primary Updated');
});

test('registry.changed can clear surfaces entirely', async t => {
  const fixture = peer53();
  const host = new ExhibitHost({ debounceMs: 5, timeoutMs: 200 });
  t.after(() => host.disconnect());
  await host.connect(fixture.transport);
  assert.equal(host.surfaces.length, 2);
  fixture.setSurfaces([]);
  fixture.event('registry.changed');
  await settle();
  assert.equal(host.surfaces.length, 0);
});

/* ------------------------------------------------------------------ *
 * Contract 5.2 backward compatibility
 * ------------------------------------------------------------------ */

test('Contract 5.2 exhibit: surfaces stays empty, no error', async t => {
  const fixture = peer52();
  const host = new ExhibitHost({ debounceMs: 5, timeoutMs: 200 });
  t.after(() => host.disconnect());
  await host.connect(fixture.transport);
  assert.equal(host.contractMinor, 2);
  assert.equal(host.surfaces.length, 0);
  assert.ok(!host.logs.some(l => l.code === 'SURFACE_CATALOG'));
});

test('Contract 5.2 exhibit: controls, state and events still work', async t => {
  const fixture = peer52();
  const host = new ExhibitHost({ debounceMs: 5, timeoutMs: 200 });
  t.after(() => host.disconnect());
  await host.connect(fixture.transport);
  assert.equal(host.status, 'connected');
  assert.equal(host.sync, 'synchronized');
  assert.equal(host.catalog.length, 1);
  assert.equal(host.surfaces.length, 0);
});

test('NGN emits xzbt 5.3 advisory on hello; 5.2 exhibit negotiates normally', async t => {
  const sentMessages = [];
  let receive, session = 0;
  const transport = {
    subscribe(fn) { receive = fn; return () => {}; },
    close() {},
    send(m) {
      sentMessages.push(m);
      const out = { xzbt: '5.2', requestId: m.requestId, sessionId: `s${session}` };
      if (m.type === 'hello') {
        session++;
        receive({ ...out, type: 'hello.result', sessionId: `s${session}`, contract: { major: 5, minor: 2 }, exhibit: { product: 'Test 5.2' } });
      } else if (m.type === 'describe') {
        receive({ ...out, type: 'describe.result', exhibit: { product: 'Test 5.2' }, contract: { major: 5, minor: 2 },
          targets: [], capabilities: [], registryRevision: 0, stateRevision: 0 });
      } else if (m.type === 'state.get') {
        receive({ ...out, type: 'state.result', stateRevision: 0, values: {} });
      }
    }
  };
  const host = new ExhibitHost({ debounceMs: 5, timeoutMs: 200 });
  t.after(() => host.disconnect());
  await host.connect(transport);
  const helloMsg = sentMessages.find(m => m.type === 'hello');
  assert.equal(helloMsg.xzbt, '5.3', 'NGN emits xzbt 5.3 advisory');
  assert.equal(host.contractMinor, 2, 'negotiated minor reflects what 5.2 exhibit reported');
  assert.equal(host.status, 'connected');
});