"""Phase 2 影响分析测试 — EXPLAIN预检 + 部分失败策略 + 上下文感知规则。"""

import pytest
from unittest.mock import MagicMock, AsyncMock, patch


# ===== EXPLAIN 预检: 表名提取 =====

class TestExtractTableNames:
    """SQL 表名提取测试。"""

    def test_update_table(self):
        from app.services.explain_preview import _extract_table_names
        assert "users" in _extract_table_names("UPDATE users SET x=1")

    def test_delete_from_table(self):
        from app.services.explain_preview import _extract_table_names
        assert "users" in _extract_table_names("DELETE FROM users WHERE id=1")

    def test_alter_table(self):
        from app.services.explain_preview import _extract_table_names
        assert "orders" in _extract_table_names("ALTER TABLE orders ADD COLUMN price DECIMAL")

    def test_drop_table(self):
        from app.services.explain_preview import _extract_table_names
        assert "temp" in _extract_table_names("DROP TABLE temp")

    def test_drop_table_if_exists(self):
        from app.services.explain_preview import _extract_table_names
        assert "temp" in _extract_table_names("DROP TABLE IF EXISTS temp")

    def test_insert_into(self):
        from app.services.explain_preview import _extract_table_names
        assert "logs" in _extract_table_names("INSERT INTO logs (msg) VALUES ('hi')")

    def test_select_from(self):
        from app.services.explain_preview import _extract_table_names
        names = _extract_table_names("SELECT * FROM users WHERE id=1")
        assert "users" in names

    def test_join_tables(self):
        from app.services.explain_preview import _extract_table_names
        names = _extract_table_names("SELECT * FROM users JOIN orders ON users.id = orders.user_id")
        assert "users" in names
        assert "orders" in names

    def test_create_table(self):
        from app.services.explain_preview import _extract_table_names
        assert "new_table" in _extract_table_names("CREATE TABLE new_table (id INT)")

    def test_create_table_if_not_exists(self):
        from app.services.explain_preview import _extract_table_names
        assert "new_table" in _extract_table_names("CREATE TABLE IF NOT EXISTS new_table (id INT)")

    def test_deduplication(self):
        from app.services.explain_preview import _extract_table_names
        names = _extract_table_names("SELECT * FROM users JOIN users AS u2 ON users.id = u2.id")
        assert names.count("users") == 1

    def test_empty_sql(self):
        from app.services.explain_preview import _extract_table_names
        assert _extract_table_names("") == []


# ===== ExplainResult 测试 =====

class TestExplainResult:
    """EXPLAIN 结果数据结构测试。"""

    def test_to_dict(self):
        from app.services.explain_preview import ExplainResult
        r = ExplainResult(
            sql="SELECT * FROM users",
            sql_type="DQL",
            estimated_rows=1000,
            full_table_scan=True,
            warnings=["Using filesort"],
        )
        d = r.to_dict()
        assert d["sql_type"] == "DQL"
        assert d["estimated_rows"] == 1000
        assert d["full_table_scan"] is True
        assert "Using filesort" in d["warnings"]

    def test_error_field(self):
        from app.services.explain_preview import ExplainResult
        r = ExplainResult(error="Connection refused")
        d = r.to_dict()
        assert d["error"] == "Connection refused"


# ===== 执行策略测试 =====

class TestExecStrategy:
    """部分失败策略测试。"""

    def test_schema_default_strategy(self):
        """TicketCreate schema 默认策略是 stop_on_error。"""
        from app.schemas.ticket import TicketCreate
        data = TicketCreate(
            title="测试工单12345",
            db_type="mysql",
            instance_id=1,
            target_database="test_db",
            sql_content="SELECT 1",
            reason="测试原因abcde",
        )
        assert data.exec_strategy == "stop_on_error"

    def test_schema_continue_strategy(self):
        from app.schemas.ticket import TicketCreate
        data = TicketCreate(
            title="测试工单12345",
            db_type="mysql",
            instance_id=1,
            target_database="test_db",
            sql_content="SELECT 1",
            reason="测试原因abcde",
            exec_strategy="continue",
        )
        assert data.exec_strategy == "continue"

    def test_schema_transaction_strategy(self):
        from app.schemas.ticket import TicketCreate
        data = TicketCreate(
            title="测试工单12345",
            db_type="mysql",
            instance_id=1,
            target_database="test_db",
            sql_content="SELECT 1",
            reason="测试原因abcde",
            exec_strategy="transaction",
        )
        assert data.exec_strategy == "transaction"


# ===== 上下文感知规则测试 =====

class TestRiskEvaluatorTableSizes:
    """risk_evaluator 大表检测测试（合并自原 CTX-001）。"""

    def test_alter_large_table_upgraded_to_high(self):
        """大表 ALTER 升级为 high。"""
        from app.services.risk_evaluator import evaluate_risk_level
        level = evaluate_risk_level(
            "ALTER TABLE big_table ADD COLUMN status INT",
            db_type="mysql",
            table_sizes={"big_table": 500000},
        )
        assert level == "high"

    def test_alter_small_table_not_upgraded(self):
        """小表 ALTER 保持 medium。"""
        from app.services.risk_evaluator import evaluate_risk_level
        level = evaluate_risk_level(
            "ALTER TABLE users ADD COLUMN age INT",
            db_type="mysql",
            table_sizes={"users": 100},
        )
        assert level == "medium"

    def test_update_large_table_upgraded_to_high(self):
        """大表 UPDATE 无 WHERE 升级为 high。"""
        from app.services.risk_evaluator import evaluate_risk_level
        level = evaluate_risk_level(
            "UPDATE big_table SET status = 1",
            db_type="mysql",
            table_sizes={"big_table": 200000},
        )
        assert level == "high"

    def test_no_table_sizes_no_upgrade(self):
        """无 table_sizes 时不升级。"""
        from app.services.risk_evaluator import evaluate_risk_level
        level = evaluate_risk_level(
            "ALTER TABLE users ADD COLUMN age INT",
            db_type="mysql",
        )
        assert level == "medium"

    def test_select_large_table_stays_low(self):
        """SELECT 大表不升级。"""
        from app.services.risk_evaluator import evaluate_risk_level
        level = evaluate_risk_level(
            "SELECT * FROM big_table",
            db_type="mysql",
            table_sizes={"big_table": 500000},
        )
        assert level == "low"