"""Hash-pinned native recovery receipts, with original completion timestamps."""
import hashlib
import json
import re
from pathlib import Path
from service_assurance import timestamp

ROOT = Path(__file__).resolve().parents[1]


def pinned_receipt(entry, root):
    path = (root / entry['path']).resolve()
    if not path.is_relative_to((root / 'docs/evidence').resolve()):
        raise ValueError('receipt outside evidence directory')
    raw = path.read_bytes()
    if hashlib.sha256(raw).hexdigest() != entry['sha256']:
        raise ValueError('receipt drift')
    return json.loads(raw)


def operation_times(receipt, now):
    start, finish = (timestamp(receipt[key]) for key in ('started_at', 'finished_at'))
    if not start <= finish <= now:
        raise ValueError('invalid receipt chronology')
    return start, finish


def primary_archive(receipt, now):
    """Accept only explicit full primary transfers, including a verified versioned GET."""
    operation_times(receipt, now)
    if (receipt['schema'] != 'platform.forgejo-primary-archive.v1'
            or receipt['status'] != 'primary_fetched_pending_application_restore'
            or receipt['stage'] != 'transfer_verified'
            or receipt['archive_profile'] != 'full'
            or not receipt['destination'].startswith(
                's3://railiance-platform-pg-backup/platform-pg/application-archives/forgejo/')
            or not re.fullmatch(r'[0-9a-f]{64}', receipt['ciphertext_sha256'])
            or not all(receipt.get(key) is True for key in
                       ('multipart_completed', 'version_pinned', 'download_hash_matches'))
            or type(receipt['ciphertext_bytes']) is not int
            or receipt['ciphertext_bytes'] <= 0
            or any(type(receipt[key]) is not int or receipt[key] != receipt['ciphertext_bytes']
                   for key in ('uploaded_bytes', 'downloaded_bytes'))):
        raise ValueError('primary archive not accepted')


def archive_signal(entry, receipt, now, root):
    if entry['signal'] == 'offsite.upload':
        primary_archive(receipt, now)
    else:
        start, _ = operation_times(receipt, now)
        if (receipt['schema'] != 'platform.forgejo-isolated-restore.v1'
                or receipt['status'] != 'restored'
                or receipt['archive_profile'] != 'full'
                or receipt['source_provider'] != 'Scaleway'
                or receipt['stage'] != 'package_blob_recovery'
                or not all(receipt.get(key) is True for key in
                           ('database_import', 'application_health', 'cleanup'))
                or not receipt['repositories_verified']
                or type(receipt['package_blobs_verified']) is not int
                or receipt['package_blobs_verified'] < 0
                or type(receipt['database_counts']['package_blobs']) is not int
                or receipt['package_blobs_verified'] != receipt['database_counts']['package_blobs']):
            raise ValueError('full application recovery not accepted')
        decryption = pinned_receipt(entry['decryption'], root)
        transfer = pinned_receipt(entry['transfer'], root)
        primary_archive(transfer, now)
        decrypt_start, decrypt_finish = operation_times(decryption, now)
        if (decryption['schema'] != 'platform.forgejo-primary-decryption.v1'
                or decryption['status'] != 'primary_fetched_pending_application_restore'
                or decryption['archive_profile'] != 'full'
                or decryption['decrypted'] is not True
                or decryption['download_hash_matches'] is not True
                or not re.fullmatch(r'[0-9a-f]{64}', decryption['plaintext_sha256'])
                or receipt['transfer_receipt_sha256'] != entry['decryption']['sha256']
                or decryption['transfer_receipt_sha256'] != entry['transfer']['sha256']
                or not timestamp(transfer['finished_at']) <= decrypt_start <= decrypt_finish <= start
                or receipt['offsite_artifact'] != transfer['destination']
                or decryption['destination'] != transfer['destination']
                or decryption['ciphertext_bytes'] != transfer['ciphertext_bytes']
                or any(r['ciphertext_sha256'] != transfer['ciphertext_sha256']
                       for r in (receipt, decryption))):
            raise ValueError('recovery provenance mismatch')
    return {'result': 'pass', 'observed_at': receipt['finished_at']}


def recovery_signals(now, root=ROOT):
    index = json.loads((root / 'assurance/recovery-evidence.json').read_text())
    if index['schema'] != 'railiance-platform.recovery-evidence.v1':
        raise ValueError('unknown recovery index')
    signals = {}
    for entry in index['receipts']:
        signal = entry['signal']
        if signal in signals or signal not in ('apps-pg.restore', 'forgejo-db.restore',
                                               'openbao.snapshot', 'offsite.upload', 'offsite.restore'):
            raise ValueError('unexpected recovery signal')
        sample = {'result': 'unavailable', 'observed_at': now.isoformat()}
        try:
            if signal.startswith('offsite.'):
                signals[signal] = archive_signal(entry, pinned_receipt(entry, root), now, root)
                continue
            path = (root / entry['path']).resolve()
            allowed = [root / 'docs/evidence']
            if signal == 'openbao.snapshot':
                allowed.append(root / 'reviews')
            if not any(path.is_relative_to(directory.resolve()) for directory in allowed):
                raise ValueError('receipt outside evidence directory')
            raw = path.read_bytes()
            if hashlib.sha256(raw).hexdigest() != entry['sha256']:
                raise ValueError('receipt drift')
            receipt = json.loads(raw)
            if signal == 'openbao.snapshot':
                required = ('snapshot_created', 'source_initialized', 'source_unsealed',
                            'snapshot_encrypted', 'encrypted_copy_off_host',
                            'encryption_verified', 'hash_verified', 'no_secret_material_recorded')
                if (receipt.get('receipt_version') != 1
                        or receipt.get('source_cluster') != 'railiance01'
                        or receipt.get('source_namespace') != 'openbao'
                        or receipt.get('cluster_id') != 'fd28df5d-98ec-57dd-42ec-9b3e4f4e53bf'
                        or not all(receipt.get(key) is True for key in required)
                        or not receipt.get('encrypted_location_ref', '').startswith('offhost-custody:')):
                    raise ValueError('snapshot not accepted')
                for key in ('snapshot_sha256', 'encrypted_snapshot_sha256'):
                    value = receipt.get(key, '')
                    if not re.fullmatch(r'sha256:[0-9a-f]{64}', value):
                        raise ValueError('snapshot hash missing')
                if timestamp(receipt['created_at']) > now:
                    raise ValueError('future snapshot')
                signals[signal] = {'result': 'pass', 'observed_at': receipt['created_at']}
                continue
            cell = signal.removesuffix('.restore')
            if (receipt['schema'] != 'platform.scaleway-primary-restore.v1'
                    or receipt['primary_destination'] != f's3://railiance-platform-pg-backup/platform-pg/{cell}/'
                    or receipt['source'] != 'Scaleway Barman base backup and WAL'
                    or receipt['stage'] != 'database_acceptance'
                    or receipt['status'] != 'verified'
                    or receipt['cleanup'] is not True
                    or receipt['production_ready'] is not True):
                raise ValueError('receipt not accepted')
            completed = timestamp(receipt['finished_at'])
            if not timestamp(receipt['started_at']) <= completed <= now:
                raise ValueError('invalid receipt chronology')
            sample = {'result': 'pass', 'observed_at': receipt['finished_at']}
        except (OSError, ValueError, KeyError, TypeError, AttributeError):
            pass
        signals[signal] = sample
    return signals