'use strict';

/**
 * W021 validation rule — milestone-prefixed phase ID convention.
 *
 * W021 fires when a phase ID's integer prefix doesn't match its enclosing
 * milestone section (e.g. phase '1-01' listed under ## v2.0 is a mismatch).
 *
 * Also covers: `gsd-tools roadmap validate` subcommand shape.
 *
 * These features do NOT exist yet — this file is written TDD-first.
 */

const { describe, test, beforeEach, afterEach } = require('node:test');
const assert = require('node:assert/strict');
const fs = require('node:fs');
const path = require('node:path');

const { runGsdTools, createTempProject, cleanup } = require('./helpers.cjs');

// ---------------------------------------------------------------------------
// Fixture builder
// ---------------------------------------------------------------------------

/**
 * Build a ROADMAP.md with milestone-prefixed sections at
 * `tmpDir/.planning/ROADMAP.md`.
 *
 * @param {string} tmpDir - Temp project root returned by createTempProject().
 * @param {Array<{version: string, label: string, phases: Array<{id: string, name: string}>}>} milestones
 *   Each milestone maps to a `## [GSD] vX.Y — Label` section; each phase maps
 *   to a `### Phase <id>: <name>` heading inside that section.
 * @param {object} [opts]
 * @param {string|null} [opts.conventionValue] - Value for the `phase_id_convention`
 *   front-matter field. Pass `null` to emit the key with a null/absent value.
 *   Omit (undefined) to use the default ('milestone-prefixed').
 */
function buildRoadmap(tmpDir, milestones, opts = {}) {
  const { conventionValue } = opts;

  let conventionLine;
  if (conventionValue === null) {
    conventionLine = 'phase_id_convention: null';
  } else if (conventionValue === undefined) {
    conventionLine = 'phase_id_convention: milestone-prefixed';
  } else {
    conventionLine = `phase_id_convention: ${conventionValue}`;
  }

  const frontmatter = `---\n${conventionLine}\n---\n\n`;

  const sections = milestones
    .map(({ version, label, phases }) => {
      const phaseBlocks = phases
        .map(({ id, name }) => `### Phase ${id}: ${name}\n**Goal:** Placeholder goal\n`)
        .join('\n');
      return `## [GSD] ${version} — ${label}\n\n${phaseBlocks}`;
    })
    .join('\n\n');

  const content = `${frontmatter}# Roadmap\n\n${sections}\n`;
  fs.writeFileSync(path.join(tmpDir, '.planning', 'ROADMAP.md'), content);
}

// ---------------------------------------------------------------------------
// Suite
// ---------------------------------------------------------------------------

describe('W021 — milestone-prefixed phase ID convention', () => {
  let tmpDir;

  beforeEach(() => {
    tmpDir = createTempProject();
  });

  afterEach(() => {
    cleanup(tmpDir);
  });

  // ── 1. Mismatch fires W021 ────────────────────────────────────────────────

  test('W021 fires when phase 1-01 is listed under ## v2.0 (mismatch)', () => {
    buildRoadmap(tmpDir, [
      {
        version: 'v2.0',
        label: 'Expansion',
        phases: [{ id: '1-01', name: 'Setup' }],
      },
    ]);

    const result = runGsdTools(['roadmap', 'validate'], tmpDir);
    assert.ok(result.success, `roadmap validate should exit 0 even with warnings: ${result.error}`);

    const out = JSON.parse(result.output);
    assert.ok(Array.isArray(out.warnings), 'output.warnings should be an array');

    const w021 = out.warnings.filter(w => w.code === 'W021');
    assert.ok(w021.length > 0, 'at least one W021 warning expected for prefix mismatch');

    const warning = w021[0];
    assert.ok(warning.message, 'W021 entry should have a message field');
  });

  // ── 2. Match does NOT fire W021 ───────────────────────────────────────────

  test('W021 does NOT fire when phase 2-01 is under ## v2.0 (match)', () => {
    buildRoadmap(tmpDir, [
      {
        version: 'v2.0',
        label: 'Expansion',
        phases: [{ id: '2-01', name: 'New thing' }],
      },
    ]);

    const result = runGsdTools(['roadmap', 'validate'], tmpDir);
    assert.ok(result.success, `roadmap validate failed: ${result.error}`);

    const out = JSON.parse(result.output);
    assert.ok(Array.isArray(out.warnings), 'output.warnings should be an array');

    const w021 = out.warnings.filter(w => w.code === 'W021');
    assert.strictEqual(w021.length, 0, 'no W021 warnings expected when prefix matches milestone');
  });

  // ── 3. Sentinel ranges are exempt ────────────────────────────────────────

  test('W021 does NOT fire for sentinel range: phase 999-01 (backlog)', () => {
    buildRoadmap(tmpDir, [
      {
        version: 'v1.0',
        label: 'Foundation',
        phases: [{ id: '999-01', name: 'Backlog item' }],
      },
    ]);

    const result = runGsdTools(['roadmap', 'validate'], tmpDir);
    assert.ok(result.success, `roadmap validate failed: ${result.error}`);

    const out = JSON.parse(result.output);
    const w021 = (out.warnings || []).filter(w => w.code === 'W021');
    assert.strictEqual(w021.length, 0, 'backlog sentinel (999-xx) should be exempt from W021');
  });

  test('W021 does NOT fire for sentinel range: phase 0-01 (pre-milestone)', () => {
    buildRoadmap(tmpDir, [
      {
        version: 'v1.0',
        label: 'Foundation',
        phases: [{ id: '0-01', name: 'Pre-milestone work' }],
      },
    ]);

    const result = runGsdTools(['roadmap', 'validate'], tmpDir);
    assert.ok(result.success, `roadmap validate failed: ${result.error}`);

    const out = JSON.parse(result.output);
    const w021 = (out.warnings || []).filter(w => w.code === 'W021');
    assert.strictEqual(w021.length, 0, 'pre-milestone sentinel (0-xx) should be exempt from W021');
  });

  // ── 4. null convention disables W021 ─────────────────────────────────────

  test('W021 does NOT fire when phase_id_convention is null (free-form roadmap)', () => {
    buildRoadmap(
      tmpDir,
      [
        {
          version: 'v2.0',
          label: 'Expansion',
          // Deliberately mismatched prefix to confirm the rule is disabled
          phases: [{ id: '1-01', name: 'Setup' }],
        },
      ],
      { conventionValue: null }
    );

    const result = runGsdTools(['roadmap', 'validate'], tmpDir);
    assert.ok(result.success, `roadmap validate failed: ${result.error}`);

    const out = JSON.parse(result.output);
    const w021 = (out.warnings || []).filter(w => w.code === 'W021');
    assert.strictEqual(w021.length, 0, 'W021 must not fire when convention is null');
  });

  // ── 5. `roadmap validate` returns JSON with warnings array ───────────────

  test("'gsd-tools roadmap validate' subcommand returns JSON with warnings array", () => {
    buildRoadmap(tmpDir, [
      {
        version: 'v1.0',
        label: 'Foundation',
        phases: [{ id: '1-01', name: 'Setup' }],
      },
    ]);

    const result = runGsdTools(['roadmap', 'validate'], tmpDir);
    assert.ok(result.success, `roadmap validate should succeed: ${result.error}`);

    let out;
    try {
      out = JSON.parse(result.output);
    } catch {
      assert.fail(`roadmap validate output is not valid JSON: ${result.output}`);
    }

    assert.ok(typeof out === 'object' && out !== null, 'output should be a JSON object');
    assert.ok(Array.isArray(out.warnings), 'output should have a warnings array');
  });

  // ── 6. W021 message includes migration command ────────────────────────────

  test('W021 warning text includes the migration command', () => {
    buildRoadmap(tmpDir, [
      {
        version: 'v2.0',
        label: 'Expansion',
        phases: [{ id: '1-01', name: 'Mismatched phase' }],
      },
    ]);

    const result = runGsdTools(['roadmap', 'validate'], tmpDir);
    assert.ok(result.success, `roadmap validate failed: ${result.error}`);

    const out = JSON.parse(result.output);
    const w021 = (out.warnings || []).filter(w => w.code === 'W021');
    assert.ok(w021.length > 0, 'W021 warning expected');

    const migrationCmd = 'gsd-tools roadmap upgrade --convention milestone-prefixed';
    const hasMigration = w021.some(w => typeof w.message === 'string' && w.message.includes(migrationCmd));
    assert.ok(
      hasMigration,
      `W021 warning message should include "${migrationCmd}". Got: ${JSON.stringify(w021.map(w => w.message))}`
    );
  });
});