"""cloud/migrate_sqlite_to_postgres.py CLI 包装层单测
（CI 第二阶段覆盖率：基线 0%）。

只测包装层本身：参数解析、行数合计打印、missing 警告分支、
unmigrated/skipped 报告行。真正的迁移逻辑在
cloud/migrations.migrate_sqlite_to_postgres，另有
test_p2_migrations / test_postgres_integration 覆盖；
本文件 patch 的是包装层调用的两个函数名，不碰迁移本身。
"""

import io
import sys
import unittest
from contextlib import redirect_stdout
from pathlib import Path
from unittest import mock

try:
    from cloud import migrate_sqlite_to_postgres as mig_cli
except ImportError:
    sys.path.insert(0, str(Path(__file__).resolve().parents[2]))
    from cloud import migrate_sqlite_to_postgres as mig_cli


def _coverage(**over):
    base = {"missing_from_migration": [],
            "unmigrated_no_pg_schema": ["legacy_x"],
            "skipped_by_design": ["audit_log"]}
    base.update(over)
    return base


class MigrateCliTest(unittest.TestCase):
    def test_totals_and_reports(self):
        with mock.patch.object(
                mig_cli, "migrate_sqlite_to_postgres",
                return_value={"users": 2, "tasks": 0}), \
                mock.patch.object(mig_cli, "migration_coverage",
                                  return_value=_coverage()):
            out = io.StringIO()
            with redirect_stdout(out):
                rc = mig_cli.main(["--sqlite", "/tmp/x.db"])
        self.assertEqual(rc, 0)
        text = out.getvalue()
        self.assertIn("users: 2", text)
        self.assertIn("tasks: 0", text)
        self.assertIn("total inserted: 2", text)
        self.assertNotIn("WARNING", text)
        self.assertIn("unmigrated (no PG schema, NOT migrated): legacy_x",
                      text)
        self.assertIn("skipped by design: audit_log", text)

    def test_missing_warning_branch(self):
        with mock.patch.object(
                mig_cli, "migrate_sqlite_to_postgres",
                return_value={}), \
                mock.patch.object(
                    mig_cli, "migration_coverage",
                    return_value=_coverage(
                        missing_from_migration=["tasks"])):
            out = io.StringIO()
            with redirect_stdout(out):
                rc = mig_cli.main(["--sqlite", "/tmp/x.db"])
        self.assertEqual(rc, 0)
        self.assertIn("WARNING missing_from_migration: tasks",
                      out.getvalue())

    def test_sqlite_arg_required(self):
        with self.assertRaises(SystemExit) as ctx:
            mig_cli.main([])
        self.assertEqual(ctx.exception.code, 2)


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