// tests/validators/plan-validator-v18.test.mjs
// plan_version 1.8 (wave 1, order 3): `Test first:` is required on every step,
// every plan carries one "run the thing" step (`End-to-end:`), the K4 step
// fields (`Interface in:`, `Interface out:`, `Review focus:`) are optional but
// never empty, and an architectural plan carries the design part. 1.7 plans
// keep validating exactly as before.

import { test } from 'node:test';
import { strict as assert } from 'node:assert';
import { execFileSync } from 'node:child_process';
import { mkdtempSync, writeFileSync, rmSync, symlinkSync } from 'node:fs';
import { join, dirname } from 'node:path';
import { tmpdir } from 'node:os';
import { fileURLToPath } from 'node:url';
import { validatePlanContent } from '../../lib/validators/plan-validator.mjs';
import {
  parseStepFields, ceremonyFromBrief, resolveCeremony, findModuleCycle, splitSections,
} from '../../lib/parsers/plan-schema.mjs';
import { buildPlan, DESIGN } from '../helpers/plan-v18-builder.mjs';

const HERE = dirname(fileURLToPath(import.meta.url));
const VALIDATOR = join(HERE, '..', '..', 'lib', 'validators', 'plan-validator.mjs');
const codes = r => r.errors.map(e => e.code);

test('a complete 1.8 architectural plan validates strict', () => {
  const r = validatePlanContent(buildPlan());
  assert.deepEqual(r.errors, [], JSON.stringify(r.errors, null, 2));
  assert.equal(r.valid, true);
  assert.equal(r.parsed.planVersion, '1.8');
  assert.equal(r.parsed.ceremony, 'architectural');
});

test('1.8: a step without `Test first:` is rejected', () => {
  const r = validatePlanContent(buildPlan({ steps: [{ testFirst: false }, { endToEnd: 'node src/cli.mjs' }] }));
  assert.equal(r.valid, false);
  assert.ok(codes(r).includes('PLAN_STEP_NO_TEST_FIRST'), codes(r).join(','));
  assert.match(r.errors.find(e => e.code === 'PLAN_STEP_NO_TEST_FIRST').message, /Step 1/);
});

test('1.8: `Test first:` must name a File and what it Verifies', () => {
  const plan = buildPlan().replace(/  - Verifies: run1\(\)[^\n]*\n/, '');
  const r = validatePlanContent(plan);
  assert.ok(codes(r).includes('PLAN_STEP_NO_TEST_FIRST'), codes(r).join(','));
});

test('1.8: a plan without a "run the thing" step is rejected', () => {
  const r = validatePlanContent(buildPlan({ steps: [{}, {}] }));
  assert.equal(r.valid, false);
  assert.ok(codes(r).includes('PLAN_NO_END_TO_END'), codes(r).join(','));
});

test('1.8: `End-to-end:` without a backticked command does not count', () => {
  const plan = buildPlan().replace(/- \*\*End-to-end:\*\* `[^`]+`/, '- **End-to-end:** run it and look');
  assert.ok(codes(validatePlanContent(plan)).includes('PLAN_NO_END_TO_END'));
});

test('1.8: K4 fields are optional, but an empty one is rejected', () => {
  const withFields = buildPlan({ steps: [
    { interfaceOut: '`run1(): number` read by Step 2', reviewFocus: 'empty input — pinned by `tests/mod1.test.mjs`' },
    { interfaceIn: '`run1()` from Step 1', endToEnd: 'node src/cli.mjs' },
  ] });
  assert.deepEqual(validatePlanContent(withFields).errors, []);
  const empty = buildPlan({ steps: [{ interfaceIn: '' }, { endToEnd: 'node src/cli.mjs' }] });
  assert.ok(codes(validatePlanContent(empty)).includes('PLAN_STEP_FIELD_EMPTY'));
});

test('1.7 plans stay valid: no Test first, no End-to-end, no design required', () => {
  const plan = buildPlan({ version: '1.7', ceremony: null, design: false, steps: [{ testFirst: false }] });
  const r = validatePlanContent(plan);
  assert.deepEqual(r.errors, [], JSON.stringify(r.errors));
  assert.equal(r.warnings.find(w => w.code === 'PLAN_VERSION_MISMATCH'), undefined);
});

test('a CRLF plan validates like its LF twin (the manifest parser used to fail on \\r)', () => {
  const r = validatePlanContent(buildPlan().replace(/\n/g, '\r\n'));
  assert.deepEqual(r.errors, [], JSON.stringify(r.errors));
});

test('1.8: --soft downgrades the 1.8 rules to warnings', () => {
  const r = validatePlanContent(buildPlan({ steps: [{ testFirst: false }, {}] }), { strict: false });
  assert.equal(r.valid, true);
  const w = r.warnings.map(x => x.code);
  assert.ok(w.includes('PLAN_STEP_NO_TEST_FIRST') && w.includes('PLAN_NO_END_TO_END'), w.join(','));
});

// --- design part (P2) gated on ceremony (K1) ---

test('ceremony: absent means architectural (heaviest on doubt), so the design part is required', () => {
  const r = validatePlanContent(buildPlan({ ceremony: null, design: false }));
  assert.ok(codes(r).includes('PLAN_DESIGN_MISSING'), codes(r).join(','));
  assert.equal(r.parsed.ceremony, 'architectural');
});

test('ceremony: small and bounded plans need no design part', () => {
  for (const c of ['small', 'bounded']) {
    const r = validatePlanContent(buildPlan({ ceremony: c, design: false }));
    assert.deepEqual(r.errors, [], `${c}: ${JSON.stringify(r.errors)}`);
  }
});

test('ceremony: an unknown class is rejected', () => {
  assert.ok(codes(validatePlanContent(buildPlan({ ceremony: 'huge' }))).includes('PLAN_CEREMONY_INVALID'));
});

test('design part: every required subsection must be present', () => {
  const r = validatePlanContent(buildPlan({ designText: DESIGN.replace('### Data Flow', '### Flow of data') }));
  const e = r.errors.find(x => x.code === 'PLAN_DESIGN_SECTION_MISSING');
  assert.ok(e, codes(r).join(','));
  assert.match(e.message, /Data Flow/);
});

test('design part: a cycle in the module map is rejected', () => {
  const cyclic = DESIGN.replace('  parser --> util[src/util.mjs]', '  parser --> util[src/util.mjs]\n  util --> cli');
  const r = validatePlanContent(buildPlan({ designText: cyclic }));
  const e = r.errors.find(x => x.code === 'PLAN_MODULE_CYCLE');
  assert.ok(e, codes(r).join(','));
  assert.match(e.message, /cli -> parser -> util -> cli/);
});

test('design part: every architecture rule names its enforcer', () => {
  const noEnforcer = DESIGN.replace('| Prefer pure functions in the parser | advisory — `.claude/rules/parser.md` | — |',
    '| Prefer pure functions in the parser | we will try | — |');
  assert.ok(codes(validatePlanContent(buildPlan({ designText: noEnforcer }))).includes('PLAN_ARCH_RULE_NO_ENFORCER'));
});

test('design part: a checked rule names the step that proves it, and the step exists', () => {
  const noProof = DESIGN.replace('src` | Step 1 |', 'src` | — |');
  assert.ok(codes(validatePlanContent(buildPlan({ designText: noProof }))).includes('PLAN_ARCH_RULE_NO_PROOF'));
  const ghost = DESIGN.replace('src` | Step 1 |', 'src` | Step 9 |');
  assert.ok(codes(validatePlanContent(buildPlan({ designText: ghost }))).includes('PLAN_ARCH_RULE_NO_PROOF'));
});

test('design part: an advisory rule says which .claude/rules/ file carries it', () => {
  const nowhere = DESIGN.replace('advisory — `.claude/rules/parser.md`', 'advisory');
  assert.ok(codes(validatePlanContent(buildPlan({ designText: nowhere }))).includes('PLAN_ARCH_RULE_NO_ENFORCER'));
});

// --- parser units ---

test('parseStepFields reads bold and plain field bullets with their blocks', () => {
  const f = parseStepFields('### Step 1: x\n\n- **Files:** `a.ts`\n- Test first:\n  - File: `t.ts`\n  - Verifies: y\n- **Interface in:** `f()`\n');
  assert.equal(f.get('Files').inline, '`a.ts`');
  assert.match(f.get('Test first').text, /File: `t\.ts`/);
  assert.equal(f.get('Interface in').inline, '`f()`');
});

test('parseStepFields stops at the next heading: a later section cannot lend the last step a field', () => {
  const f = parseStepFields('### Step 2: x\n\n- **Files:** `a.ts`\n\n## Verification\n\n- **End-to-end:** `npm start`\n');
  assert.equal(f.has('End-to-end'), false);
  const plan = buildPlan({ steps: [{}, {}] }).replace('## Verification\n', '## Verification\n\n- **End-to-end:** `npm start` → expected: up\n');
  assert.ok(codes(validatePlanContent(plan)).includes('PLAN_NO_END_TO_END'), 'only a step can be the run step');
});

test('findModuleCycle finds a cycle through labelled and chained edges', () => {
  assert.equal(findModuleCycle('graph TD\n  a --> b\n  b -->|uses| c\n'), null);
  assert.deepEqual(findModuleCycle('graph LR\n  a --> b --> c\n  c -.-> a\n'), ['a', 'b', 'c', 'a']);
});

// --- review findings (independent code review, 06.10) ---

test('ceremony is read only from frontmatter or the header line, never from prose', () => {
  const plan = buildPlan({ ceremony: null, design: false })
    .replace('Why: the brief asks for a parser CLI.', 'Why: the brief once said `ceremony: small`.\nceremony: small');
  const r = validatePlanContent(plan);
  assert.equal(r.parsed.ceremony, 'architectural');
  assert.ok(codes(r).includes('PLAN_DESIGN_MISSING'));
});

test('module map: the edge forms mermaid allows are all read, so their cycles are caught', () => {
  const cyclic = [
    'a-->b\nb-->a',
    'a <--> b',
    'a ---> b\nb ===> a',
    'a -. uses .-> b\nb == calls ==> a',
    'a -- calls --> b\nb --> a',
    'a & c --> b\nb --> a',
    'a --> b; b --> a',
    'a:::hot --> b\nb --> a',
    'a{{hex}} --> b[[sub]]\nb --> a',
    'end-user --> api\napi --> end-user',
    'graph.mjs --> x\nx --> graph.mjs',
  ];
  for (const body of cyclic) {
    assert.ok(findModuleCycle(`graph TD\n${body}\n`), `cycle not found in: ${JSON.stringify(body)}`);
  }
  assert.equal(findModuleCycle('graph TD\n  a --- b\n  b --> a\n'), null, 'an undirected link is not a dependency');
});

test('module map: a link line the parser cannot read is an error, not silently dropped', () => {
  const odd = DESIGN.replace('  parser --> util[src/util.mjs]', '  parser --> util[src/util.mjs]\n  util --> @weird id');
  assert.ok(codes(validatePlanContent(buildPlan({ designText: odd }))).includes('PLAN_MODULE_MAP_UNPARSED'));
});

test('module map: a cycle across two mermaid blocks is caught', () => {
  const two = DESIGN.replace('  parser --> util[src/util.mjs]\n```',
    '  parser --> util[src/util.mjs]\n```\n\n```mermaid\ngraph TD\n  util --> cli\n```');
  assert.ok(codes(validatePlanContent(buildPlan({ designText: two }))).includes('PLAN_MODULE_CYCLE'));
});

test('findModuleCycle survives a 20 000-node chain (iterative, no stack overflow)', () => {
  const edges = [];
  for (let i = 0; i < 20000; i++) edges.push([`n${i}`, `n${i + 1}`]);
  assert.equal(findModuleCycle(edges), null);
  edges.push(['n20000', 'n0']);
  assert.equal(findModuleCycle(edges).length, 20002);
});

test('Test first with an empty File: or Verifies: does not count', () => {
  const noPath = buildPlan().replace('  - File: `tests/mod1.test.mjs` (new)', '  - File:');
  assert.ok(codes(validatePlanContent(noPath)).includes('PLAN_STEP_NO_TEST_FIRST'));
  const noWhat = buildPlan().replace(/  - Verifies: run1\(\)[^\n]*/, '  - Verifies:');
  assert.ok(codes(validatePlanContent(noWhat)).includes('PLAN_STEP_NO_TEST_FIRST'));
});

test('a column-0 # comment inside a fenced block does not end the step fields', () => {
  const f = parseStepFields('### Step 1: x\n\n- **Changes:** run\n  ```bash\n# a comment\nnpm test\n  ```\n- **Test first:**\n  - File: `t.mjs`\n  - Verifies: y\n');
  assert.ok(f.has('Test first'));
});

test('a ~~~ line inside a ``` block does not end the fence (headings in code stay code)', () => {
  const t = '## A\n\n```md\n~~~\n## Not a heading\n~~~\n```\n\n## B\n';
  assert.deepEqual(splitSections(t, 2).filter(s => s.title).map(s => s.title), ['A', 'B']);
});

test('K1 stub: ceremonyFromBrief reads the brief frontmatter; absent → architectural', () => {
  assert.equal(ceremonyFromBrief('---\ntype: brief\nceremony: small\n---\n# B\n').value, 'small');
  const none = ceremonyFromBrief('---\ntype: brief\n---\n# B\n');
  assert.equal(none.value, 'architectural');
  assert.equal(none.defaulted, true);
  assert.equal(resolveCeremony('huge').valid, false);
});

// --- CLI: strict is the default, and the main-module guard survives a symlink ---

test('CLI --strict exits 1 on a 1.8 plan missing Test first; exits 0 through a symlinked path with a space', () => {
  const dir = mkdtempSync(join(tmpdir(), 'plan v18 '));
  try {
    const bad = join(dir, 'bad.md');
    writeFileSync(bad, buildPlan({ steps: [{ testFirst: false }, { endToEnd: 'node x' }] }));
    let code = 0;
    try { execFileSync('node', [VALIDATOR, '--strict', '--json', bad], { stdio: 'pipe' }); } catch (e) { code = e.status; }
    assert.equal(code, 1);
    const good = join(dir, 'good.md');
    writeFileSync(good, buildPlan());
    const link = join(dir, 'linked validator.mjs');
    symlinkSync(VALIDATOR, link);
    const out = execFileSync('node', [link, '--json', good], { encoding: 'utf-8' });
    assert.equal(JSON.parse(out).valid, true, 'symlinked CLI must run, not silently no-op');
  } finally {
    rmSync(dir, { recursive: true, force: true });
  }
});