"""话题ID扩展/回填验证，复用独立测试库连接配置。"""
import os
import re
import unittest
from pathlib import Path
from urllib.parse import urlsplit

@unittest.skipUnless(os.getenv("QINGHE_INTEGRITY_TEST_URL"), "未配置独立测试库")
class TopicIdMigrationTest(unittest.TestCase):
    def setUp(self):
        import pymysql
        e=urlsplit(os.environ["QINGHE_INTEGRITY_TEST_URL"].removeprefix("jdbc:"))
        if not re.fullmatch(r"qinghe_integrity_test_[a-z0-9_]+", e.path.strip("/")):raise ValueError("禁止业务库")
        self.db=pymysql.connect(host=e.hostname,port=e.port or 3306,database=e.path.strip("/"),
            user=os.environ["QINGHE_INTEGRITY_TEST_USER"],password=os.environ["QINGHE_INTEGRITY_TEST_PASSWORD"],charset="utf8mb4")
        self.addCleanup(self.db.close)
        self.tables=["topic_follow","topic_favorite","topic_visit","topic_hot_snapshot"]
        with self.db.cursor() as q:
            for t in self.tables+ [t+"_bak_v24_id" for t in self.tables]+["topic"]:q.execute("DROP TABLE IF EXISTS `"+t+"`")
            q.execute("CREATE TABLE topic(id VARCHAR(36) PRIMARY KEY,name VARCHAR(100) UNIQUE,created_at DATETIME,deleted TINYINT) ENGINE=InnoDB COLLATE=utf8mb4_unicode_ci")
            q.execute("INSERT INTO topic VALUES('old-id','旧名_deleted_old', '2026-01-01',1),('new-id','旧名','2026-10-01',0)")
            for t in self.tables:
                q.execute("CREATE TABLE `"+t+"` (id VARCHAR(36) PRIMARY KEY,user_id VARCHAR(36),topic_name VARCHAR(100),created_at DATETIME,captured_at DATETIME) ENGINE=InnoDB")
                q.execute("INSERT INTO `"+t+"`(id,user_id,topic_name,created_at) VALUES('valid','u1','旧名','2026-10-02'),('deleted-parent','u2','旧名_deleted_old','2026-02-01'),('ambiguous','u3','旧名','2026-02-01'),('missing','u4','不存在','2026-10-02')")
        self.db.commit()

    def run_script(self, file):
        text=(Path(__file__).resolve().parents[1]/"src/main/resources/db/migration"/file).read_text(encoding="utf-8")
        text="\n".join(line for line in text.splitlines() if not line.lstrip().startswith("--"))
        try:
            with self.db.cursor() as q:
                for s in text.split(";"):
                    if s.strip():q.execute(s)
        except Exception:self.db.rollback();raise

    def test_expand_preview_apply_repeat_and_ambiguous_rows(self):
        self.run_script("V23__expand_topic_stable_id.sql")
        self.run_script("V23__expand_topic_stable_id.sql")
        self.run_script("V24__backfill_topic_stable_id.sql")
        with self.db.cursor() as q:
            q.execute("SELECT COUNT(*) FROM topic_follow WHERE topic_id IS NOT NULL");self.assertEqual(0,q.fetchone()[0])
            q.execute("SET @topic_id_apply=1")
        self.run_script("V24__backfill_topic_stable_id.sql")
        with self.db.cursor() as q:
            for t in self.tables:
                q.execute("SELECT id,topic_id FROM `"+t+"`");rows=dict(q.fetchall())
                self.assertEqual("new-id",rows["valid"]);self.assertEqual("old-id",rows["deleted-parent"])
                self.assertIsNone(rows["ambiguous"]);self.assertIsNone(rows["missing"])
            q.execute("SET @topic_id_apply=1")
        self.run_script("V24__backfill_topic_stable_id.sql")
        with self.db.cursor() as q:
            q.execute("SELECT COUNT(*) FROM topic_follow_bak_v24_id");self.assertEqual(2,q.fetchone()[0])