'use strict';

const assert = require('node:assert/strict');
const fs = require('node:fs');
const os = require('node:os');
const path = require('node:path');
const versioning = require('../../scripts/lib/skill-evolution/versioning');
const health = require('../../scripts/lib/skill-evolution/health');

let passed = 0;
let failed = 0;

function createFixture() {
  const root = fs.mkdtempSync(path.join(os.tmpdir(), 'skill-evolution-storage-'));
  const skillDir = path.join(root, 'skills', 'demo');
  fs.mkdirSync(skillDir, { recursive: true });
  fs.writeFileSync(path.join(skillDir, 'SKILL.md'), '# Original\n');
  return { root, skillDir, versionsDir: versioning.getVersionsDir(skillDir) };
}

function test(name, fn) {
  const fixture = createFixture();
  try {
    fn(fixture);
    passed += 1;
    console.log(`  ✓ ${name}`);
  } catch (error) {
    failed += 1;
    console.error(`  ✗ ${name}: ${error.message}`);
  } finally {
    fs.rmSync(fixture.root, { recursive: true, force: true });
  }
}

test('snapshot creation preserves occupied directories and links plus earlier snapshots', fixture => {
  const { root, skillDir, versionsDir } = fixture;
  versioning.createVersion(skillDir);
  fs.mkdirSync(path.join(versionsDir, 'v2.md'));
  fs.writeFileSync(path.join(versionsDir, 'v2.md', 'keep.txt'), 'preserve');
  if (process.platform !== 'win32') {
    fs.symlinkSync(path.join(root, 'missing'), path.join(versionsDir, 'v3.md'));
  }
  fs.writeFileSync(path.join(skillDir, 'SKILL.md'), '# Updated\n');
  const snapshot = versioning.createVersion(skillDir);
  assert.equal(snapshot.version, process.platform === 'win32' ? 3 : 4);
  assert.equal(fs.readFileSync(snapshot.path, 'utf8'), '# Updated\n');
  assert.equal(fs.readFileSync(path.join(versionsDir, 'v1.md'), 'utf8'), '# Original\n');
  assert.equal(fs.readFileSync(path.join(versionsDir, 'v2.md', 'keep.txt'), 'utf8'), 'preserve');
  assert.equal(versioning.getEvolutionLog(skillDir, 'amendments').at(-1).version, snapshot.version);
  if (process.platform !== 'win32') {
    assert.ok(fs.lstatSync(path.join(versionsDir, 'v3.md')).isSymbolicLink());
    fs.symlinkSync(path.join(versionsDir, 'v1.md'), path.join(versionsDir, 'v5.md'));
    assert.deepEqual(versioning.listVersions(skillDir).map(entry => entry.version), [1, 4, 5]);
    assert.equal(versioning.getCurrentVersion(skillDir), 5);
  }
});

test('health skips malformed amendment rows while retaining a valid pending proposal', fixture => {
  const { root, skillDir } = fixture;
  versioning.ensureSkillVersioning(skillDir);
  fs.writeFileSync(versioning.getEvolutionLogPath(skillDir, 'amendments'),
    'null\n[]\n42\n{bad}\n{"event":"proposal","status":"pending"}\n');
  const report = health.collectSkillHealth({
    skillsRoot: path.join(root, 'skills'), homeDir: root, now: '2026-03-15T12:00:00.000Z',
  });
  assert.equal(report.skills.find(skill => skill.skill_id === 'demo').pending_amendments, 1);
});

test('snapshot allocation ignores invalid numeric names and preserves their contents', fixture => {
  const { skillDir, versionsDir } = fixture;
  fs.mkdirSync(versionsDir);
  const names = ['v0.md', 'v9007199254740992.md', `v${'9'.repeat(80)}.md`];
  for (const name of names) fs.writeFileSync(path.join(versionsDir, name), 'preserve');
  assert.deepEqual(versioning.listVersions(skillDir), []);
  const snapshot = versioning.createVersion(skillDir);
  assert.equal(snapshot.version, 1);
  assert.equal(fs.readFileSync(snapshot.path, 'utf8'), '# Original\n');
  for (const name of names) assert.equal(fs.readFileSync(path.join(versionsDir, name), 'utf8'), 'preserve');
});

test('exhausted snapshot numbering refuses creation before initializing evolution logs', fixture => {
  const { skillDir, versionsDir } = fixture;
  fs.mkdirSync(versionsDir);
  const last = path.join(versionsDir, `v${Number.MAX_SAFE_INTEGER}.md`);
  fs.writeFileSync(last, 'preserve');
  assert.throws(() => versioning.createVersion(skillDir), /snapshot version range is exhausted/);
  assert.deepEqual(fs.readdirSync(versionsDir), [`v${Number.MAX_SAFE_INTEGER}.md`]);
  assert.equal(fs.readFileSync(last, 'utf8'), 'preserve');
  assert.equal(fs.existsSync(versioning.getEvolutionDir(skillDir)), false);
});

test('an occupied final safe snapshot path refuses creation while preserving the directory', fixture => {
  const { skillDir, versionsDir } = fixture;
  fs.mkdirSync(versionsDir);
  fs.writeFileSync(path.join(versionsDir, `v${Number.MAX_SAFE_INTEGER - 1}.md`), 'preserve');
  const occupied = path.join(versionsDir, `v${Number.MAX_SAFE_INTEGER}.md`);
  fs.mkdirSync(occupied);
  fs.writeFileSync(path.join(occupied, 'keep.txt'), 'preserve');
  assert.throws(() => versioning.createVersion(skillDir), /snapshot version range is exhausted/);
  assert.equal(fs.readdirSync(versionsDir).length, 2);
  assert.equal(fs.readFileSync(path.join(occupied, 'keep.txt'), 'utf8'), 'preserve');
  assert.equal(fs.existsSync(versioning.getEvolutionDir(skillDir)), false);
});

test('exhausted rollback preserves unsnapshotted content, snapshot files and evolution state', fixture => {
  const { skillDir, versionsDir } = fixture;
  fs.mkdirSync(versionsDir);
  const previous = path.join(versionsDir, 'v1.md');
  const last = path.join(versionsDir, `v${Number.MAX_SAFE_INTEGER}.md`);
  fs.writeFileSync(previous, '# Previous\n');
  fs.writeFileSync(last, '# Latest snapshot\n');
  const assertPreserved = () => {
    assert.equal(fs.readFileSync(path.join(skillDir, 'SKILL.md'), 'utf8'), '# Original\n');
    assert.equal(fs.readFileSync(previous, 'utf8'), '# Previous\n');
    assert.equal(fs.readFileSync(last, 'utf8'), '# Latest snapshot\n');
    assert.equal(fs.readdirSync(versionsDir).length, 2);
  };
  assert.throws(() => versioning.rollbackTo(skillDir, 1), /snapshot version range is exhausted/);
  assertPreserved();
  assert.equal(fs.existsSync(versioning.getEvolutionDir(skillDir)), false);
  versioning.ensureSkillVersioning(skillDir);
  const logs = versioning.EVOLUTION_LOG_TYPES.map(type => versioning.getEvolutionLogPath(skillDir, type));
  for (const file of logs) fs.writeFileSync(file, '{"event":"preserve"}\n');
  assert.throws(() => versioning.rollbackTo(skillDir, 1), /snapshot version range is exhausted/);
  assertPreserved();
  for (const file of logs) assert.equal(fs.readFileSync(file, 'utf8'), '{"event":"preserve"}\n');
});

test('unsafe rollback targets preserve the live skill and excluded snapshots', fixture => {
  const { skillDir, versionsDir } = fixture;
  fs.mkdirSync(versionsDir);
  const invalid = path.join(versionsDir, 'v9007199254740992.md');
  fs.writeFileSync(invalid, '# Excluded snapshot\n');
  for (const target of [9007199254740992, '9007199254740992']) {
    assert.throws(() => versioning.rollbackTo(skillDir, target), /Invalid target version/);
    assert.equal(fs.readFileSync(path.join(skillDir, 'SKILL.md'), 'utf8'), '# Original\n');
    assert.equal(fs.readFileSync(invalid, 'utf8'), '# Excluded snapshot\n');
    assert.equal(fs.readdirSync(versionsDir).length, 1);
    assert.equal(fs.existsSync(versioning.getEvolutionDir(skillDir)), false);
  }
});

console.log(`Results: Passed: ${passed}, Failed: ${failed}`);
process.exitCode = failed > 0 ? 1 : 0;