use sea_orm::{Database, ConnectionTrait, Statement, DatabaseBackend};

use erp_server_migration::MigratorTrait;

/// 测试数据库 — 使用本地 PostgreSQL 创建隔离测试库
///
/// 连接本地 PostgreSQL（wiki/infrastructure.md 配置），为每个测试创建独立的测试数据库。
/// 不依赖 Docker/Testcontainers，与开发环境一致。
pub struct TestDb {
    db: Option<sea_orm::DatabaseConnection>,
    db_name: String,
}

impl TestDb {
    pub async fn new() -> Self {
        let db_name = format!("erp_test_{}", uuid::Uuid::now_v7().simple());

        // 连接本地 PostgreSQL 的默认库（postgres）来创建测试库
        let admin_url = "postgres://postgres:123123@localhost:5432/postgres";
        let admin_db = Database::connect(admin_url)
            .await
            .expect("连接本地 PostgreSQL 失败，请确认服务正在运行");

        admin_db
            .execute(Statement::from_string(
                DatabaseBackend::Postgres,
                format!("CREATE DATABASE \"{}\"", db_name),
            ))
            .await
            .expect("创建测试数据库失败");

        drop(admin_db);

        // 连接测试库
        let test_url = format!("postgres://postgres:123123@localhost:5432/{}", db_name);
        let db = Database::connect(&test_url)
            .await
            .expect("连接测试数据库失败");

        // 运行所有迁移
        erp_server_migration::Migrator::up(&db, None)
            .await
            .expect("执行数据库迁移失败");

        Self { db: Some(db), db_name }
    }

    /// 获取数据库连接引用
    pub fn db(&self) -> &sea_orm::DatabaseConnection {
        self.db.as_ref().expect("数据库连接已被释放")
    }
}

impl Drop for TestDb {
    fn drop(&mut self) {
        let db_name = self.db_name.clone();
        self.db.take();

        // 尝试在独立线程中清理，避免在 tokio runtime 内创建新 runtime
        let _ = std::thread::spawn(move || {
            let rt = tokio::runtime::Builder::new_current_thread()
                .enable_all()
                .build();
            if let Ok(rt) = rt {
                rt.block_on(async {
                    let admin_url = "postgres://postgres:123123@localhost:5432/postgres";
                    if let Ok(admin_db) = Database::connect(admin_url).await {
                        let disconnect_sql = format!(
                            "SELECT pg_terminate_backend(pid) FROM pg_stat_activity WHERE datname = '{}'",
                            db_name
                        );
                        admin_db
                            .execute(Statement::from_string(DatabaseBackend::Postgres, disconnect_sql))
                            .await
                            .ok();

                        admin_db
                            .execute(Statement::from_string(
                                DatabaseBackend::Postgres,
                                format!("DROP DATABASE IF EXISTS \"{}\"", db_name),
                            ))
                            .await
                            .ok();
                    }
                });
            }
        });
    }
}