import hashlib
import http.client
import json
import os
import shutil
import stat
import subprocess
import tempfile
import time

BASE = '/www/backup/txiaw-mysql-fix-20260831'
STAGE = BASE + '/stage'
WEB = '/www/wwwroot/www.txiaw.com'
PHP = '/www/server/php/56/bin/php'
TEMPLATE = WEB + '/Tpl/icp/gxl_index.html'
HELPER = WEB + '/Lib/HomeNewsCache.php'
RUNTIME = WEB + '/Runtime/TxiawHomeNews'
QUERY = b"gxl_mysql_news('field:news_id,news_cid,news_name;limit:100;order:news_addtime desc')"
REPLACEMENT = b"txiaw_home_news_cached()"

if not os.path.exists(BASE + '/index-result.json'):
    raise RuntimeError('Verify the new database index before enabling the cache')
manifest = json.load(open(STAGE + '/baseline.json'))
baseline = next(item for item in manifest if item['remote'] == TEMPLATE)
original = open(TEMPLATE, 'rb').read()
if hashlib.sha256(original).hexdigest() != baseline['sha256']:
    raise RuntimeError('Homepage template changed since inspection; refusing overwrite')
if os.path.exists(HELPER):
    raise RuntimeError('Unexpected cache helper already exists')
assert original.count(QUERY) == 1
modified = original.replace(b'<php>$jishu =' + QUERY, b"<php>require_once APP_PATH . 'HomeNewsCache.php'; $jishu =" + REPLACEMENT, 1)
assert modified != original and QUERY not in modified

for name in ['HomeNewsCache.php', 'test_home_news_cache.php']:
    subprocess.run([PHP, '-n', '-l', STAGE + '/' + name], check=True, timeout=10)
unit_dir = tempfile.mkdtemp(prefix='cache-unit-', dir=BASE)
subprocess.run([PHP, '-n', STAGE + '/test_home_news_cache.php', unit_dir], check=True, timeout=10)
subprocess.run(['python3', STAGE + '/test_cache_concurrency.py'], check=True, timeout=15)

def atomic_write(data, target, metadata):
    fd, tmp = tempfile.mkstemp(prefix='.txiaw-repair-', suffix='.tmp', dir=os.path.dirname(target))
    try:
        with os.fdopen(fd, 'wb') as f:
            f.write(data)
            f.flush()
            os.fsync(f.fileno())
        os.chmod(tmp, stat.S_IMODE(metadata.st_mode))
        os.chown(tmp, metadata.st_uid, metadata.st_gid)
        os.replace(tmp, target)
    finally:
        if os.path.exists(tmp):
            os.unlink(tmp)

template_info = os.stat(TEMPLATE)
runtime_info = os.stat(WEB + '/Runtime')
if not os.path.isdir(RUNTIME):
    os.mkdir(RUNTIME, 0o750)
    os.chown(RUNTIME, runtime_info.st_uid, runtime_info.st_gid)

compiled = []
cache_root = os.path.realpath(WEB + '/Runtime/Cache')
compiled_backup = BASE + '/compiled-home-before'
os.makedirs(compiled_backup, mode=0o700, exist_ok=True)
for root, dirs, files in os.walk(cache_root):
    dirs[:] = [d for d in dirs if not os.path.islink(os.path.join(root, d))]
    for name in files:
        path = os.path.join(root, name)
        if not name.endswith('.php') or os.path.islink(path) or os.path.getsize(path) > 2 * 1024 * 1024:
            continue
        if os.path.commonpath([cache_root, os.path.realpath(path)]) != cache_root:
            raise RuntimeError('Compiled-cache path escaped site cache root')
        data = open(path, 'rb').read()
        if QUERY in data:
            backup = compiled_backup + '/' + hashlib.sha256(path.encode()).hexdigest() + '.php'
            shutil.copy2(path, backup)
            info = os.stat(path)
            os.chmod(backup, 0o600)
            compiled.append((path, backup, info))

def request(path):
    c = http.client.HTTPConnection('127.0.0.1', 80, timeout=10)
    started = time.monotonic()
    c.request('GET', path, headers={'Host': 'www.txiaw.com', 'User-Agent': 'Codex-Repair-Check/1.0'})
    r = c.getresponse()
    data = r.read()
    result = {'path': path, 'status': r.status, 'bytes': len(data), 'seconds': round(time.monotonic() - started, 4)}
    c.close()
    if r.status != 200 or len(data) < 1000:
        raise RuntimeError('Homepage check failed: ' + str(result))
    return result

try:
    atomic_write(open(STAGE + '/HomeNewsCache.php', 'rb').read(), HELPER, os.stat(WEB + '/Lib/HomeRequestProtection.php'))
    atomic_write(modified, TEMPLATE, template_info)
    for path, backup, info in compiled:
        os.unlink(path)
    probes = [request('/')]
    cache_path = RUNTIME + '/news-list-v1.json'
    entry = json.load(open(cache_path))
    if len(entry['items']) != 100:
        raise RuntimeError('Cache did not preserve the expected 100 list items')
    digest = hashlib.sha256(open(cache_path, 'rb').read()).hexdigest()
    probes.append(request('/?r=codex-cache-key-check'))
    if digest != hashlib.sha256(open(cache_path, 'rb').read()).hexdigest():
        raise RuntimeError('Query parameter unexpectedly changed the fresh list cache')
except Exception:
    atomic_write(original, TEMPLATE, template_info)
    # Keep the harmless helper available to any in-flight newly compiled template.
    for path, backup, info in compiled:
        atomic_write(open(backup, 'rb').read(), path, info)
    raise

result = {'status': 'installed', 'ttl_seconds': 60, 'stale_seconds': 300, 'items': len(entry['items']), 'invalidated_compiled_files': [p for p, _, _ in compiled], 'http_probes': probes, 'query_argument_reuses_cache': True}
json.dump(result, open(BASE + '/cache-result.json', 'w'), indent=2)
print('CACHE_DEPLOYED', json.dumps(result), flush=True)