# -*- coding: utf-8 -*-
"""业务运行上下文管理 API。"""

from __future__ import annotations

import logging
from datetime import date

from fastapi import APIRouter, Depends, HTTPException, Query, status
from psycopg2.extras import RealDictCursor

from app.auth.dependencies import CurrentUser, get_current_user
from app.database import get_connection
from app.schemas.runtime_context import (
    RuntimeContextResponse,
    RuntimeSwitchRequest,
    RuntimeSwitchResponse,
    RuntimeTransitionStep,
)
from app.services.runtime_context import (
    MODE_LIVE,
    MODE_SANDBOX,
    RuntimeContext,
    get_runtime_context,
    new_sandbox_instance_id,
)

logger = logging.getLogger(__name__)

router = APIRouter(prefix="/api/admin/runtime-context", tags=["业务运行上下文"])
config_router = APIRouter(prefix="/api/config", tags=["业务配置"])


def _require_super_admin(user: CurrentUser) -> None:
    if "super_admin" not in user.roles:
        raise HTTPException(
            status_code=status.HTTP_403_FORBIDDEN,
            detail="仅超级管理员可切换业务运行上下文",
        )


def _context_response(ctx: RuntimeContext) -> RuntimeContextResponse:
    return RuntimeContextResponse(**ctx.to_dict())


@config_router.get("/runtime-context", response_model=RuntimeContextResponse)
async def get_current_runtime_context(
    user: CurrentUser = Depends(get_current_user),
) -> RuntimeContextResponse:
    """返回当前登录用户门店的业务运行上下文。"""
    return _context_response(get_runtime_context(user.site_id))


@router.get("", response_model=RuntimeContextResponse)
async def get_admin_runtime_context(
    site_id: int = Query(..., ge=1),
    user: CurrentUser = Depends(get_current_user),
) -> RuntimeContextResponse:
    """系统管理端按门店查看业务运行上下文。"""
    _require_super_admin(user)
    return _context_response(get_runtime_context(site_id))


@router.get("/sites")
async def list_runtime_sites(
    user: CurrentUser = Depends(get_current_user),
) -> list[dict]:
    """列出可配置门店及其当前运行上下文。"""
    _require_super_admin(user)
    conn = get_connection()
    try:
        with conn.cursor(cursor_factory=RealDictCursor) as cur:
            cur.execute(
                """
                SELECT s.site_id, s.site_name, s.site_code, s.is_active,
                       c.mode, c.sandbox_date, c.sandbox_instance_id,
                       c.ai_mode, c.status, c.updated_at
                FROM biz.sites s
                LEFT JOIN biz.site_runtime_context c ON c.site_id = s.site_id
                ORDER BY s.is_active DESC, s.site_id
                """
            )
            rows = cur.fetchall()
        conn.commit()
    except Exception:
        conn.rollback()
        raise
    finally:
        conn.close()

    return [dict(row) for row in rows]


@router.patch("", response_model=RuntimeSwitchResponse)
async def switch_runtime_context(
    body: RuntimeSwitchRequest,
    user: CurrentUser = Depends(get_current_user),
) -> RuntimeSwitchResponse:
    """切换门店业务运行上下文。

    切换前会终止当前运行中的 ETL、取消未完成 AI 触发记录。
    `biz.trigger_jobs` 是全局调度表（无 site_id 列），不随单门店沙箱切换暂停；
    多门店隔离完全通过 runtime_mode + sandbox_instance_id 实现。
    """
    _require_super_admin(user)

    if body.mode == MODE_SANDBOX and body.sandbox_date is None:
        raise HTTPException(status_code=422, detail="沙箱模式必须设置 sandbox_date")
    if body.mode == MODE_LIVE and body.sandbox_date is not None:
        raise HTTPException(status_code=422, detail="live 模式不能设置 sandbox_date")
    if body.mode == MODE_SANDBOX and body.sandbox_date and body.sandbox_date > date.today():
        raise HTTPException(status_code=422, detail="sandbox_date 不能晚于真实今天")

    steps: list[RuntimeTransitionStep] = []
    steps.extend(await _stop_runtime_activity(body.site_id))

    conn = get_connection()
    try:
        with conn.cursor() as cur:
            old_ctx = get_runtime_context(body.site_id, conn=conn)
            sandbox_instance_id = None
            if body.mode == MODE_SANDBOX:
                if body.reset_sandbox or not old_ctx.sandbox_instance_id:
                    sandbox_instance_id = new_sandbox_instance_id()
                else:
                    sandbox_instance_id = old_ctx.sandbox_instance_id

            cur.execute(
                """
                INSERT INTO biz.site_runtime_context
                    (site_id, mode, sandbox_date, sandbox_instance_id, ai_mode,
                     status, updated_by, updated_at, reason)
                VALUES (%s, %s, %s, %s, 'live', 'active', %s, NOW(), %s)
                ON CONFLICT (site_id)
                DO UPDATE SET
                    mode = EXCLUDED.mode,
                    sandbox_date = EXCLUDED.sandbox_date,
                    sandbox_instance_id = EXCLUDED.sandbox_instance_id,
                    ai_mode = EXCLUDED.ai_mode,
                    status = EXCLUDED.status,
                    updated_by = EXCLUDED.updated_by,
                    updated_at = NOW(),
                    reason = EXCLUDED.reason
                """,
                (
                    body.site_id,
                    body.mode,
                    body.sandbox_date,
                    sandbox_instance_id,
                    user.user_id,
                    body.reason,
                ),
            )

            steps.append(RuntimeTransitionStep(
                key="biz_triggers_unchanged",
                title="保持业务触发器",
                status="skipped",
                count=0,
                detail=(
                    "biz.trigger_jobs 为全局调度表（无 site_id 列），单门店沙箱切换不影响其它门店；"
                    "沙箱隔离由 runtime_mode + sandbox_instance_id 在数据写入层完成。"
                ),
            ))

        conn.commit()
    except Exception:
        conn.rollback()
        logger.exception("切换业务运行上下文失败: site_id=%s", body.site_id)
        raise
    finally:
        conn.close()

    ctx = get_runtime_context(body.site_id)
    steps.append(RuntimeTransitionStep(
        key="apply_context",
        title="写入业务运行上下文",
        status="success",
        detail=(
            f"当前模式={ctx.mode}，业务日期={ctx.business_date}"
            + (f"，沙箱实例={ctx.sandbox_instance_id}" if ctx.is_sandbox else "")
        ),
    ))
    return RuntimeSwitchResponse(context=_context_response(ctx), steps=steps)


async def _stop_runtime_activity(site_id: int) -> list[RuntimeTransitionStep]:
    """终止切换前仍在运行的 ETL/AI/队列活动。"""
    steps: list[RuntimeTransitionStep] = []

    # 1. 终止当前进程内 ETL 执行。
    try:
        from app.services.task_executor import task_executor

        running_ids = task_executor.get_running_ids()
        cancelled = 0
        for execution_id in running_ids:
            if await task_executor.cancel(execution_id):
                cancelled += 1
        steps.append(RuntimeTransitionStep(
            key="cancel_etl_processes",
            title="终止当前 ETL 执行",
            status="success",
            count=cancelled,
            detail=f"检测到 {len(running_ids)} 个当前进程内执行，已发送取消信号。",
        ))
    except Exception as exc:
        logger.exception("终止 ETL 执行失败")
        steps.append(RuntimeTransitionStep(
            key="cancel_etl_processes",
            title="终止当前 ETL 执行",
            status="warning",
            detail=str(exc)[:300],
        ))

    # 2. 清理当前门店队列中未完成任务。
    conn = get_connection()
    try:
        with conn.cursor() as cur:
            cur.execute(
                """
                UPDATE task_queue
                SET status = 'cancelled',
                    finished_at = NOW(),
                    error_message = COALESCE(error_message, '') || E'\n[runtime-context] 切换业务运行上下文时取消'
                WHERE site_id = %s
                  AND status IN ('pending', 'running')
                """,
                (site_id,),
            )
            queue_cancelled = cur.rowcount
        conn.commit()
        steps.append(RuntimeTransitionStep(
            key="cancel_task_queue",
            title="取消 ETL 队列",
            status="success",
            count=queue_cancelled,
            detail="已取消当前门店 pending/running 的 task_queue 记录。",
        ))
    except Exception as exc:
        conn.rollback()
        logger.exception("取消 ETL 队列失败")
        steps.append(RuntimeTransitionStep(
            key="cancel_task_queue",
            title="取消 ETL 队列",
            status="warning",
            detail=str(exc)[:300],
        ))
    finally:
        conn.close()

    # 3. 取消当前站点内存 AI 调用链，并标记未完成 ai_trigger_jobs。
    try:
        from app.ai.dispatcher import get_dispatcher

        dispatcher = get_dispatcher()
        cancelled = dispatcher.cancel_running(site_id)
        steps.append(RuntimeTransitionStep(
            key="cancel_ai_runtime",
            title="取消当前 AI 调用链",
            status="success",
            count=cancelled,
            detail="已取消当前进程内属于该门店的 AI 异步调用链。",
        ))
    except Exception as exc:
        steps.append(RuntimeTransitionStep(
            key="cancel_ai_runtime",
            title="取消当前 AI 调用链",
            status="warning",
            detail=f"AI Dispatcher 不可用或取消失败：{str(exc)[:240]}",
        ))

    conn = get_connection()
    try:
        with conn.cursor() as cur:
            cur.execute(
                """
                UPDATE biz.ai_trigger_jobs
                SET status = 'cancelled',
                    finished_at = NOW(),
                    error_message = COALESCE(error_message, '') || E'\n[runtime-context] 切换业务运行上下文时取消'
                WHERE site_id = %s
                  AND status IN ('pending', 'running')
                """,
                (site_id,),
            )
            ai_cancelled = cur.rowcount
        conn.commit()
        steps.append(RuntimeTransitionStep(
            key="cancel_ai_jobs",
            title="标记未完成 AI 触发",
            status="success",
            count=ai_cancelled,
            detail="已将当前门店 pending/running 的 ai_trigger_jobs 标记为 cancelled。",
        ))
    except Exception as exc:
        conn.rollback()
        logger.exception("标记 AI 触发失败")
        steps.append(RuntimeTransitionStep(
            key="cancel_ai_jobs",
            title="标记未完成 AI 触发",
            status="warning",
            detail=str(exc)[:300],
        ))
    finally:
        conn.close()

    return steps