import pytest
import subprocess
import os
from pathlib import Path

# 项目根目录
PROJECT_ROOT = "/Users/Chiguyong/Code/Fischer/geo/backend"

# 从迁移文件 a79329c23b20_initial_complete_schema.py 提取的实际表名
REQUIRED_TABLES = [
    "agent_registry",
    "api_keys",
    "brands",
    "optimization_insights",
    "organizations",
    "platform_rule_versions",
    "platform_rules",
    "publish_records",
    "alert_settings",
    "alerts",
    "competitor_insights",
    "competitors",
    "content_metrics",
    "detection_tasks",
    "diagnosis_records",
    "monitoring_records",
    "schema_suggestions",
    "suggestions",
    "trend_insights",
    "usage_records",
    "users",
    "agent_configs",
    "brand_knowledge",
    "content_baselines",
    "geo_plans",
    "knowledge_bases",
    "knowledge_search_logs",
    "lifecycle_projects",
    "org_members",
    "payment_orders",
    "queries",
    "subscriptions",
    "agent_tasks",
    "citation_records",
    "contents",
    "geo_plan_actions",
    "keywords",
    "knowledge_documents",
    "project_stages",
    "query_tasks",
    "agent_task_logs",
    "attribution_records",
    "content_reviews",
    "content_versions",
    "distribution_schedules",
    "knowledge_chunks",
    "knowledge_entities",
    "knowledge_relations",
]


class TestDatabaseMigration:
    """数据库迁移验证测试"""

    def test_alembic_current_shows_no_errors(self):
        """alembic current 应无错误输出"""
        result = subprocess.run(
            ["alembic", "current"],
            cwd=PROJECT_ROOT,
            capture_output=True,
            text=True
        )
        if result.returncode != 0 and "gaierror" in result.stderr:
            pytest.skip("数据库不可用，跳过 alembic current 测试")
        assert result.returncode == 0, f"alembic current failed: {result.stderr}"

    def test_all_required_tables_exist(self):
        """所有必需表应存在"""
        import asyncio
        import sys
        sys.path.insert(0, os.path.join(PROJECT_ROOT, "app"))

        async def check_tables():
            from app.database import engine
            from sqlalchemy import inspect

            async with engine.connect() as conn:
                tables = await conn.run_sync(lambda sync_conn: inspect(sync_conn).get_table_names())
                return set(tables)

        try:
            existing_tables = asyncio.run(check_tables())
        except Exception as e:
            pytest.skip(f"无法连接数据库: {e}")

        missing_tables = [t for t in REQUIRED_TABLES if t not in existing_tables]
        assert not missing_tables, f"缺失表: {missing_tables}"

    def test_migration_head_matches_models(self):
        """迁移头应与模型定义一致"""
        result = subprocess.run(
            ["alembic", "check"],
            cwd=PROJECT_ROOT,
            capture_output=True,
            text=True
        )
        if result.returncode != 0 and "gaierror" in result.stderr:
            pytest.skip("数据库不可用，跳过 alembic check 测试")
        assert result.returncode == 0, f"alembic check failed: {result.stderr}"

    def test_no_duplicate_migration_versions(self):
        """迁移版本号应唯一"""
        versions_dir = Path(PROJECT_ROOT) / "alembic" / "versions"
        if not versions_dir.exists():
            pytest.skip("alembic/versions/ 目录不存在")

        version_files = list(versions_dir.glob("*.py"))
        version_numbers = []

        for f in version_files:
            name = f.stem
            if "_" in name:
                version_num = name.split("_")[0]
                version_numbers.append((version_num, f.name))

        seen = {}
        duplicates = []
        for version_num, filename in version_numbers:
            if version_num in seen:
                duplicates.append((version_num, filename, seen[version_num]))
            else:
                seen[version_num] = filename

        assert not duplicates, f"发现重复版本号: {duplicates}"

    def test_foreign_keys_integrity(self):
        """关键外键约束应存在"""
        import asyncio
        import sys
        sys.path.insert(0, os.path.join(PROJECT_ROOT, "app"))

        async def check_fks():
            from app.database import engine
            from sqlalchemy import inspect

            async with engine.connect() as conn:
                fks = await conn.run_sync(
                    lambda sync_conn: inspect(sync_conn).get_foreign_keys("brands")
                )
                return fks

        try:
            foreign_keys = asyncio.run(check_fks())
        except Exception as e:
            pytest.skip(f"无法连接数据库: {e}")

        fk_columns = [fk['constrained_columns'] for fk in foreign_keys]

        has_user_fk = any('user_id' in cols for cols in fk_columns)
        assert has_user_fk, "brands 表缺少 user_id 外键"

    def test_alembic_history_shows_migrations(self):
        """alembic history 应显示迁移历史"""
        result = subprocess.run(
            ["alembic", "history"],
            cwd=PROJECT_ROOT,
            capture_output=True,
            text=True
        )
        if result.returncode != 0 and "gaierror" in result.stderr:
            pytest.skip("数据库不可用，跳过 alembic history 测试")
        assert result.returncode == 0, f"alembic history failed: {result.stderr}"
        assert result.stdout.strip(), "alembic history 为空"

    @pytest.mark.skipif(
        os.environ.get("CI") is None,
        reason="alembic check drift detection 仅在 CI 环境中运行（需要完整数据库）"
    )
    def test_alembic_check_detects_drift(self):
        """alembic check 应检测到模型与迁移之间的漂移"""
        result = subprocess.run(
            ["alembic", "check"],
            cwd=PROJECT_ROOT,
            capture_output=True,
            text=True
        )
        # returncode 0 表示无漂移，非零表示存在漂移
        assert result.returncode == 0, (
            f"检测到迁移漂移！模型定义与迁移文件不一致:\n{result.stderr}\n{result.stdout}"
        )