/**
 * Tests for `state prune` command (#1970).
 */

'use strict';

const { test, describe, 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');

function writeStateMd(tmpDir, content) {
  fs.writeFileSync(path.join(tmpDir, '.planning', 'STATE.md'), content);
}

function readStateMd(tmpDir) {
  return fs.readFileSync(path.join(tmpDir, '.planning', 'STATE.md'), 'utf-8');
}

function archiveExists(tmpDir) {
  return fs.existsSync(path.join(tmpDir, '.planning', 'STATE-ARCHIVE.md'));
}

function readArchive(tmpDir) {
  return fs.readFileSync(path.join(tmpDir, '.planning', 'STATE-ARCHIVE.md'), 'utf-8');
}

describe('state prune (#1970)', () => {
  let tmpDir;

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

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

  test('prunes decisions older than cutoff', () => {
    writeStateMd(tmpDir, [
      '# Session State',
      '',
      '**Current Phase:** 10',
      '',
      '## Decisions',
      '',
      '- [Phase 1]: Old decision',
      '- [Phase 3]: Old decision 3',
      '- [Phase 8]: Recent decision',
      '- [Phase 10]: Current decision',
      '',
    ].join('\n'));

    const result = runGsdTools('state prune --keep-recent 3', tmpDir);
    assert.ok(result.success, `Command failed: ${result.error}`);

    const output = JSON.parse(result.output);
    assert.strictEqual(output.pruned, true);
    assert.strictEqual(output.cutoff_phase, 7);

    const newState = readStateMd(tmpDir);
    assert.match(newState, /\[Phase 8\]: Recent decision/);
    assert.match(newState, /\[Phase 10\]: Current decision/);
    assert.doesNotMatch(newState, /\[Phase 1\]: Old decision/);
    assert.doesNotMatch(newState, /\[Phase 3\]: Old decision 3/);

    assert.ok(archiveExists(tmpDir), 'STATE-ARCHIVE.md should exist');
    const archive = readArchive(tmpDir);
    assert.match(archive, /\[Phase 1\]: Old decision/);
    assert.match(archive, /\[Phase 3\]: Old decision 3/);
  });

  test('--dry-run reports what would be pruned without modifying STATE.md', () => {
    const originalContent = [
      '# Session State',
      '',
      '**Current Phase:** 10',
      '',
      '## Decisions',
      '',
      '- [Phase 1]: Old decision',
      '- [Phase 2]: Another old decision',
      '- [Phase 9]: Recent decision',
      '',
    ].join('\n');
    writeStateMd(tmpDir, originalContent);

    const result = runGsdTools('state prune --keep-recent 3 --dry-run', tmpDir);
    assert.ok(result.success, `Command failed: ${result.error}`);

    const output = JSON.parse(result.output);
    assert.strictEqual(output.pruned, false);
    assert.strictEqual(output.dry_run, true);
    assert.strictEqual(output.total_would_archive, 2);

    // STATE.md should be unchanged
    const unchanged = readStateMd(tmpDir);
    assert.strictEqual(unchanged, originalContent);

    // No archive file should be created
    assert.ok(!archiveExists(tmpDir), 'dry-run should not create archive');
  });

  test('prunes resolved blockers older than cutoff', () => {
    writeStateMd(tmpDir, [
      '# Session State',
      '',
      '**Current Phase:** 10',
      '',
      '## Blockers',
      '',
      '- ~~Phase 1: Old resolved issue~~',
      '- [RESOLVED] Phase 2: Another old issue',
      '- Phase 9: Current blocker (unresolved)',
      '',
    ].join('\n'));

    const result = runGsdTools('state prune --keep-recent 3', tmpDir);
    assert.ok(result.success, `Command failed: ${result.error}`);

    const output = JSON.parse(result.output);
    assert.strictEqual(output.pruned, true);
    const blockerSection = output.sections.find(s => /Blockers/i.test(s.section));
    assert.ok(blockerSection, 'should report Blockers section');
    assert.strictEqual(blockerSection.entries_archived, 2);

    const newState = readStateMd(tmpDir);
    assert.match(newState, /Phase 9: Current blocker/);
    assert.doesNotMatch(newState, /Phase 1: Old resolved issue/);
  });

  test('returns pruned:false when nothing to prune', () => {
    writeStateMd(tmpDir, [
      '# Session State',
      '',
      '**Current Phase:** 2',
      '',
      '## Decisions',
      '',
      '- [Phase 1]: Recent decision',
      '- [Phase 2]: Current decision',
      '',
    ].join('\n'));

    const result = runGsdTools('state prune --keep-recent 3', tmpDir);
    assert.ok(result.success, `Command failed: ${result.error}`);

    const output = JSON.parse(result.output);
    assert.strictEqual(output.pruned, false);
  });
});