import hashlib
import json
import os
from pathlib import Path

import pytest

from tools.runtime.report_files import (apply_moves, migration_plan, report_log,
    report_output, resolve_report_input, retention_plan)


def test_migration_preserves_operational_data_and_report_bytes(tmp_path):
    for name in ['documents.json', 'chunks.json', 'index_version.json', '.reindex.lock', 'zp_index.sqlite']:
        (tmp_path/name).write_text('operational')
    (tmp_path/'old.json').write_bytes(b'{"old":true}\n')
    (tmp_path/'old.pytest.log').write_text('log')
    plan = migration_plan(tmp_path)
    assert {Path(m['source']).name for m in plan} == {'old.json', 'old.pytest.log'}
    journal = apply_moves(plan, data_dir=tmp_path)
    assert len(json.loads(journal.read_text())['moves']) == 2
    for move in plan:
        assert hashlib.sha256(Path(move['destination']).read_bytes()).hexdigest() == move['sha256']
        assert resolve_report_input(Path(move['source']), data_dir=tmp_path) == Path(move['destination'])
    assert (tmp_path/'documents.json').read_text() == 'operational'
    assert not migration_plan(tmp_path)


def test_no_overwrites_and_changed_plan_is_rejected_before_any_move(tmp_path):
    for name in ['a.json','b.json']:
        (tmp_path/name).write_text('{}')
    plan = migration_plan(tmp_path)
    (tmp_path/'b.json').write_text('{"changed":1}')
    with pytest.raises(RuntimeError):
        apply_moves(plan, data_dir=tmp_path)
    assert (tmp_path/'a.json').exists()
    output = report_output(None, 'verification', data_dir=tmp_path)
    output.write_text('{}')
    with pytest.raises(FileExistsError):
        report_output(output, 'verification', data_dir=tmp_path)
    for name in ['documents.json', 'chunks.json', 'index_version.json', 'zp_index.sqlite']:
        with pytest.raises(ValueError):
            report_output(tmp_path/name, 'verification', data_dir=tmp_path)


def test_flat_legacy_output_is_redirected_and_unique_default_has_separate_log(tmp_path):
    output = report_output(tmp_path/'old.json', 'verification', data_dir=tmp_path)
    assert output == tmp_path/'reports/verification/old.json'
    assert report_log(output, data_dir=tmp_path) == tmp_path/'logs/verification/old.pytest.log'
    assert report_output(None, 'verification', data_dir=tmp_path) != report_output(None, 'verification', data_dir=tmp_path)
    assert report_log(tmp_path/'custom/result.json', data_dir=tmp_path).parent == tmp_path/'logs/custom'


def test_retention_archives_only_completed_verifications_and_follows_move_chain(tmp_path):
    outputs = []
    for i in range(8):
        output = report_output(tmp_path/f'run{i}.json', 'verification', data_dir=tmp_path)
        output.write_text(json.dumps({'passed': bool(i%2)}))
        os.utime(output, (100+i,100+i))
        report_log(output, data_dir=tmp_path).write_text('log')
        outputs.append(output)
    incomplete = tmp_path/'reports/verification/incomplete.json'
    incomplete.write_text('{}')
    experiment = report_output(None, 'rag_verified', data_dir=tmp_path)
    experiment.write_text('{"passed":true}')
    plan = retention_plan(tmp_path, keep=5)
    assert len(plan) == 6
    apply_moves(plan, data_dir=tmp_path)
    assert incomplete.exists() and experiment.exists()
    assert len(list((tmp_path/'reports/verification').glob('*.json'))) == 6
    archived = resolve_report_input(outputs[0], data_dir=tmp_path)
    assert archived.exists() and archived.parent == tmp_path/'reports/archive/verification'
    next_target = tmp_path/'reports/archive/older'/archived.name
    apply_moves([{'source':str(archived),'destination':str(next_target),
                  'sha256':hashlib.sha256(archived.read_bytes()).hexdigest()}], data_dir=tmp_path)
    assert resolve_report_input(outputs[0], data_dir=tmp_path) == next_target