"""Only temporary synthetic seals are used; production publication is never run."""
import hashlib
import json
from pathlib import Path
import tempfile
import unittest
from unittest import mock

import publication


def _sha(path):
    return hashlib.sha256(path.read_bytes()).hexdigest()


def _write(path, value):
    path.parent.mkdir(parents=True, exist_ok=True)
    path.write_text(json.dumps(value), encoding='utf-8')


def _seal(root):
    rows = [dict(path=path.relative_to(root).as_posix(), bytes=path.stat().st_size, sha256=_sha(path))
            for path in sorted(root.rglob('*')) if path.is_file() and
            path.name not in ('manifest.json', 'checksums.sha256') and '__pycache__' not in path.parts]
    _write(root / 'manifest.json', dict(root=str(root), files=rows))
    lines = [row['sha256'] + '  ' + row['path'] for row in rows]
    lines.append(_sha(root / 'manifest.json') + '  manifest.json')
    (root / 'checksums.sha256').write_text('\n'.join(lines) + '\n', encoding='utf-8')


class PublicationTests(unittest.TestCase):
    def setUp(self):
        self.temporary = tempfile.TemporaryDirectory(prefix='phase4ai-publication-unit-')
        self.addCleanup(self.temporary.cleanup)
        self.root = Path(self.temporary.name).resolve()
        self.model = self.root / publication.MODEL_RELATIVE
        self.experiment = self.root / publication.EXPERIMENT_RELATIVE
        self.registry = self.root / publication.REGISTRY_RELATIVE
        self.model.mkdir(parents=True)
        self.experiment.mkdir(parents=True)
        (self.model / 'module.py').write_text('# synthetic\n', encoding='utf-8')
        status = dict(status=publication.FINAL_STATUS, pass_all=True, candidate_generated=False,
                      learning_achieved=False, new_brain_simulation=False, GPU_used=False)
        _write(self.experiment / 'audit/final-status.json', status)
        _write(self.experiment / 'trials/example/summary.json', dict(synthetic=True))
        _write(self.experiment / 'trials/example/apl-summary.json', dict(synthetic=True))
        (self.experiment / 'REPORT.md').write_text('Synthetic evidence.\n', encoding='utf-8')
        (self.experiment / 'unit-tests.log').write_text('Synthetic tests passed.\n', encoding='utf-8')
        (self.experiment / 'counts.npy').write_bytes(b'not-a-real-array')
        _seal(self.model)
        _seal(self.experiment)

    def test_all_payload_and_checksum_self_hash_are_verified(self):
        result = publication.verify_seal(self.experiment)
        self.assertTrue(result['pass_all'])
        self.assertEqual(result['payload_file_count'], 6)
        self.assertEqual(result['manifest_sha256'], _sha(self.experiment / 'manifest.json'))

    def test_publication_only_copies_small_evidence_and_leaves_sources_unchanged(self):
        before = {str(path): _sha(path) for base in (self.model, self.experiment)
                  for path in base.rglob('*') if path.is_file()}
        outcome = publication.publish(self.root)
        self.assertTrue(outcome['publication_complete'])
        self.assertFalse(outcome['scientific_gate_executed_by_publisher'])
        self.assertTrue((self.registry / 'evidence/trials/example/apl-summary.json').is_file())
        self.assertTrue((self.registry / 'evidence/unit-tests.log').is_file())
        self.assertFalse((self.registry / 'evidence/counts.npy').exists())
        self.assertFalse((self.registry / 'model/module.py').exists())
        self.assertTrue((self.registry / 'model/manifest.json').is_file())
        receipt = json.loads((self.registry / 'publication-receipt.json').read_text())
        self.assertFalse(receipt['complete_bulk_backup'])
        self.assertFalse(receipt['scientific_gate_certified_by_publication'])
        for row in receipt['files']:
            path = self.registry / row['path']
            self.assertEqual(path.stat().st_size, row['bytes'])
            self.assertEqual(_sha(path), row['sha256'])
        for name, checksum in before.items():
            self.assertEqual(_sha(Path(name)), checksum)

    def test_existing_registry_is_never_overwritten_or_resumed(self):
        self.registry.mkdir(parents=True)
        sentinel = self.registry / 'keep.txt'
        sentinel.write_text('keep', encoding='utf-8')
        with self.assertRaisesRegex(ValueError, 'Registry already exists'):
            publication.publish(self.root)
        self.assertEqual(sentinel.read_text(), 'keep')
        self.assertEqual(list(self.registry.iterdir()), [sentinel])

    def test_bulk_payload_corruption_blocks_before_registry_creation(self):
        (self.experiment / 'counts.npy').write_bytes(b'corrupt')
        with self.assertRaisesRegex(ValueError, 'Payload byte count mismatch'):
            publication.publish(self.root)
        self.assertFalse(self.registry.exists())

    def test_same_size_payload_hash_corruption_is_detected(self):
        path = self.experiment / 'counts.npy'
        path.write_bytes(b'x' * path.stat().st_size)
        with self.assertRaisesRegex(ValueError, 'Payload SHA-256 mismatch'):
            publication.verify_seal(self.experiment)

    def test_missing_payload_or_unlisted_file_is_detected(self):
        (self.experiment / 'extra.txt').write_text('unlisted', encoding='utf-8')
        with self.assertRaisesRegex(ValueError, 'unlisted/missing'):
            publication.verify_seal(self.experiment)

    def test_wrong_manifest_self_checksum_is_detected(self):
        path = self.experiment / 'checksums.sha256'
        lines = path.read_text().splitlines()
        lines[-1] = '0' * 64 + '  manifest.json'
        path.write_text('\n'.join(lines) + '\n')
        with self.assertRaisesRegex(ValueError, 'manifest self-checksum'):
            publication.verify_seal(self.experiment)

    def test_duplicate_checksum_path_is_detected(self):
        path = self.experiment / 'checksums.sha256'
        text = path.read_text()
        path.write_text(text + text.splitlines()[0] + '\n')
        with self.assertRaisesRegex(ValueError, 'Duplicate checksum'):
            publication.verify_seal(self.experiment)

    def test_manifest_root_mismatch_is_detected(self):
        path = self.experiment / 'manifest.json'
        value = json.loads(path.read_text())
        value['root'] = str(self.model)
        _write(path, value)
        with self.assertRaisesRegex(ValueError, 'another root'):
            publication.verify_seal(self.experiment)

    def test_manifest_duplicate_path_and_traversal_are_rejected(self):
        manifest = self.experiment / 'manifest.json'
        original = json.loads(manifest.read_text())
        for bad_path in ('../escape.txt', '/absolute', 'a/../escape', 'a\\escape', 'C:/escape'):
            with self.subTest(path=bad_path):
                value = json.loads(json.dumps(original))
                value['files'][0]['path'] = bad_path
                _write(manifest, value)
                with self.assertRaises(ValueError):
                    publication.verify_seal(self.experiment)
        original['files'].append(original['files'][0].copy())
        _write(manifest, original)
        with self.assertRaisesRegex(ValueError, 'Duplicate manifest path'):
            publication.verify_seal(self.experiment)

    def test_explicitly_excluded_pycache_is_not_published(self):
        cache = self.experiment / '__pycache__/unused.pyc'
        cache.parent.mkdir()
        cache.write_bytes(b'cache')
        self.assertEqual(publication.verify_seal(self.experiment)['excluded_pycache_files'], 1)
        publication.publish(self.root)
        self.assertFalse((self.registry / 'evidence/__pycache__').exists())

    def test_file_size_limit_skips_large_json_without_omitting_verification(self):
        huge = self.experiment / 'huge.json'
        huge.write_bytes(b' ' * (publication.MAX_EVIDENCE_BYTES + 1))
        _seal(self.experiment)
        publication.publish(self.root)
        self.assertFalse((self.registry / 'evidence/huge.json').exists())
        receipt = json.loads((self.registry / 'publication-receipt.json').read_text())
        omitted = {row['path']: row for row in receipt['experiment_payload_not_copied']}
        self.assertEqual(omitted['huge.json']['reason'], 'exceeds_4_MiB')

    def test_unexpected_final_status_or_scope_flag_blocks_publication(self):
        path = self.experiment / 'audit/final-status.json'
        original = json.loads(path.read_text())
        for field, value in [('status', 'OTHER-PASS'), ('pass_all', False), ('learning_achieved', True),
                             ('GPU_used', True), ('new_brain_simulation', True), ('candidate_generated', True)]:
            with self.subTest(field=field):
                bad = dict(original)
                bad[field] = value
                _write(path, bad)
                _seal(self.experiment)
                with self.assertRaises(ValueError):
                    publication.publish(self.root)
                self.assertFalse(self.registry.exists())

    def test_copy_failure_is_retained_without_success_receipt(self):
        with mock.patch.object(publication, '_copy_verified', side_effect=OSError('synthetic interruption')):
            with self.assertRaisesRegex(OSError, 'synthetic interruption'):
                publication.publish(self.root)
        self.assertTrue(self.registry.is_dir())
        self.assertTrue((self.registry / 'publication-failure.json').is_file())
        self.assertFalse((self.registry / 'publication-receipt.json').exists())
        with self.assertRaisesRegex(ValueError, 'Registry already exists'):
            publication.publish(self.root)

    def test_source_change_during_copy_prevents_success(self):
        original = publication._copy_verified
        changed = False

        def copy_then_modify(source, target, byte_count, checksum):
            nonlocal changed
            original(source, target, byte_count, checksum)
            if not changed:
                changed = True
                (self.experiment / 'counts.npy').write_bytes(b'deliberately-changed-after-initial-verification')

        with mock.patch.object(publication, '_copy_verified', side_effect=copy_then_modify):
            with self.assertRaisesRegex(ValueError, 'Payload byte count mismatch'):
                publication.publish(self.root)
        self.assertFalse((self.registry / 'publication-receipt.json').exists())
        self.assertTrue((self.registry / 'publication-failure.json').exists())


if __name__ == '__main__':
    unittest.main()