"""契约快照测试公共工具。

契约 = 前端/数据依赖的硬不变量：
- 路由 (METHOD /path)
- 权限字符串 (@permission_required("sys:..."))
- 数据库表名

用法：设置环境变量 UPDATE_GOLDEN=1 运行一次以重新生成 golden。
"""
import glob
import json
import os
import re

GOLDEN_DIR = os.path.join(os.path.dirname(os.path.abspath(__file__)), "golden")

PERMISSION_RE = re.compile(r'@permission_required\(\s*["\'](sys:[^"\']+)["\']')

UPDATE_GOLDEN = os.getenv("UPDATE_GOLDEN") == "1"


def collect_routes():
    """通过 openapi schema 收集全部 (METHOD /path)，去重排序。"""
    from core.app import create_app

    app = create_app()
    spec = app.openapi()
    return sorted(
        f"{method.upper()} {path}"
        for path, methods in spec["paths"].items()
        for method in methods
    )


def collect_permissions():
    """静态扫描源码中的 @permission_required("sys:...") 权限串。"""
    perms = set()
    for root in ("apps", "modules"):
        for path in glob.glob(os.path.join(root, "**", "*.py"), recursive=True):
            with open(path, encoding="utf-8") as f:
                perms.update(PERMISSION_RE.findall(f.read()))
    return sorted(perms)


def collect_tables():
    """从 SQLAlchemy metadata 收集全部表名。"""
    from core.database import Base

    return sorted(Base.metadata.tables.keys())


def compare_snapshot(name: str, actual: list):
    """与 golden 对比；UPDATE_GOLDEN=1 时重新生成并跳过断言。"""
    path = os.path.join(GOLDEN_DIR, name)
    if UPDATE_GOLDEN:
        os.makedirs(GOLDEN_DIR, exist_ok=True)
        with open(path, "w", encoding="utf-8") as f:
            json.dump(actual, f, ensure_ascii=False, indent=2)
        return
    with open(path, encoding="utf-8") as f:
        golden = json.load(f)
    assert actual == golden, (
        f"契约快照 [{name}] 不一致！\n"
        f"新增: {sorted(set(actual) - set(golden))}\n"
        f"缺失: {sorted(set(golden) - set(actual))}"
    )