"""异步数据库引擎 + 会话。

- engine / SessionLocal:全局单例
- get_session:FastAPI 依赖,按请求注入一个会话
- sync_interface_definitions:启动时同步接口定义;表结构由 Alembic 管理
"""

from collections.abc import AsyncGenerator
import json

import settings
from services.interface_catalog import INTERFACE_DEFINITIONS
from sqlalchemy import text
from sqlalchemy.ext.asyncio import (
    AsyncSession,
    async_sessionmaker,
    create_async_engine,
)

engine = create_async_engine(settings.DATABASE_URL, echo=False, pool_pre_ping=True)
SessionLocal = async_sessionmaker(engine, expire_on_commit=False)


async def get_session() -> AsyncGenerator[AsyncSession, None]:
    async with SessionLocal() as session:
        yield session


async def sync_interface_definitions() -> None:
    async with engine.begin() as conn:
        for definition in INTERFACE_DEFINITIONS:
            await conn.execute(
                text(
                    "INSERT INTO interface_definitions "
                    "(interface_type, name, capability, field_schema, enabled, version) "
                    "VALUES (:interface_type, :name, :capability, CAST(:field_schema AS jsonb), TRUE, 1) "
                    "ON CONFLICT (interface_type) DO UPDATE SET "
                    "name = EXCLUDED.name, capability = EXCLUDED.capability, "
                    "field_schema = EXCLUDED.field_schema, enabled = TRUE, updated_at = now()"
                ),
                {
                    "interface_type": definition["interface_type"],
                    "name": definition["name"],
                    "capability": definition["capability"],
                    "field_schema": json.dumps({"fields": definition["fields"]}),
                },
            )


async def sync_default_tools() -> None:
    """Ensure system-provided reusable tools exist without overwriting edits."""
    default_tools = [
        {
            "id": "tool_end_call_default",
            "name": "结束对话",
            "function_name": "end_call",
            "type": "end_call",
            "description": "当用户明确要求结束对话，或任务已完成时调用。",
            "definition": {
                "schema_version": 1,
                "type": "end_call",
                "config": {
                    "message_type": "none",
                    "custom_message": "",
                    "capture_reason": True,
                },
            },
        },
        {
            "id": "tool_show_message_default",
            "name": "显示确认消息",
            "function_name": "show_message",
            "type": "client",
            "description": "向用户显示必须主动确认的重要消息弹窗。",
            "definition": {
                "schema_version": 1,
                "type": "client",
                "config": {
                    "allow_interruptions": False,
                    "execution_mode": "immediate",
                    "wait_for_response": True,
                    "response_wait_mode": "session",
                    "timeout_seconds": 3,
                    "parameters": [
                        {
                            "name": "title",
                            "type": "string",
                            "location": "body",
                            "description": "弹窗标题",
                            "required": False,
                        },
                        {
                            "name": "message",
                            "type": "string",
                            "location": "body",
                            "description": "需要用户确认的重要信息",
                            "required": True,
                        },
                        {
                            "name": "actions",
                            "type": "array",
                            "location": "body",
                            "description": "可选操作按钮",
                            "required": False,
                        },
                        {
                            "name": "dismissible",
                            "type": "boolean",
                            "location": "body",
                            "description": "是否允许不选择按钮直接关闭",
                            "required": False,
                        },
                    ],
                    "dynamic_variable_assignments": {},
                },
            },
        },
    ]
    async with engine.begin() as conn:
        for tool in default_tools:
            await conn.execute(
                text(
                    "INSERT INTO tools "
                    "(id, name, function_name, type, description, definition, secrets, status) "
                    "VALUES ("
                    ":id, :name, :function_name, :type, :description, "
                    "CAST(:definition AS jsonb), CAST(:secrets AS jsonb), :status"
                    ") "
                    "ON CONFLICT (function_name) DO NOTHING"
                ),
                {
                    **tool,
                    "definition": json.dumps(tool["definition"]),
                    "secrets": "{}",
                    "status": "active",
                },
            )