from __future__ import annotations

import json
from datetime import datetime
from typing import Any
from zoneinfo import ZoneInfo

from croniter import croniter
from markupsafe import Markup
from sqladmin import ModelView, action
from sqladmin.filters import BooleanFilter, OperationColumnFilter, StaticValuesFilter
from sqladmin.models import Request
from starlette.responses import RedirectResponse

from app.admin.filters import RecentDateTimeFilter
from app.db.models import Job, JobLog
from app.plugins.manager import load_job_class
from app.security.fernet import encrypt_json
from app.tasks.execute import execute_job


def _maybe_json(value: Any) -> Any:
    if isinstance(value, str):
        s = value.strip()
        if not s:
            return value
        try:
            return json.loads(s)
        except json.JSONDecodeError:
            return value
    return value


def _fmt_dt_seconds(dt: datetime | None) -> str:
    if not dt:
        return ""
    # DB 中保存的时间多为 naive；按 UTC 解释后转换为 Asia/Shanghai 展示
    tz = ZoneInfo("Asia/Shanghai")
    if dt.tzinfo is None:
        dt = dt.replace(tzinfo=ZoneInfo("UTC"))
    return dt.astimezone(tz).strftime("%Y-%m-%d %H:%M:%S")


def _truncate(s: str, n: int = 120) -> str:
    s = s or ""
    return (s[: n - 3] + "...") if len(s) > n else s


class JobAdmin(ModelView, model=Job):
    name = "任务"
    name_plural = "任务"
    icon = "fa fa-cogs"

    column_list = [Job.id, Job.enabled, Job.cron_expr, Job.handler_path, Job.updated_at]
    column_details_list = [
        Job.id,
        Job.enabled,
        Job.cron_expr,
        Job.handler_path,
        Job.public_cfg,
        Job.secret_cfg,
        Job.last_run_at,
        Job.created_at,
        Job.updated_at,
    ]

    # 允许在表单中编辑主键（创建 Job 必填）
    form_include_pk = True
    form_columns = [Job.id, Job.enabled, Job.cron_expr, Job.handler_path, Job.public_cfg, Job.secret_cfg]

    # 为 Job 详情页指定模板（用于调整按钮间距）
    details_template = "job_details.html"

    # 编辑页：secret_cfg 只写不读（不回显密文；留空表示不更新）
    edit_template = "job_edit.html"

    # 列表页模板：加入每行 Run Now
    list_template = "job_list.html"

    # 编辑页排除 secret_cfg，避免回显密文；由自定义模板额外渲染一个空输入框
    # 注意：SQLAdmin 这里需要字段名字符串（不是 SQLAlchemy Column 对象）
    form_edit_rules = ["id", "enabled", "cron_expr", "handler_path", "public_cfg"]

    column_labels = {
        "id": "任务ID",
        "enabled": "启用",
        "cron_expr": "Cron 表达式",
        "handler_path": "处理器",
        "public_cfg": "明文配置",
        "secret_cfg": "密文配置",
        "last_run_at": "上次运行时间",
        "created_at": "创建时间",
        "updated_at": "更新时间",
    }

    column_formatters = {
        Job.created_at: lambda m, a: _fmt_dt_seconds(m.created_at),
        Job.updated_at: lambda m, a: _fmt_dt_seconds(m.updated_at),
        Job.last_run_at: lambda m, a: _fmt_dt_seconds(m.last_run_at),
    }

    column_formatters_detail = {
        Job.created_at: lambda m, a: _fmt_dt_seconds(m.created_at),
        Job.updated_at: lambda m, a: _fmt_dt_seconds(m.updated_at),
        Job.last_run_at: lambda m, a: _fmt_dt_seconds(m.last_run_at),
    }

    # 搜索：顶部 Search 输入框
    column_searchable_list = [Job.id, Job.handler_path, Job.cron_expr]

    # 筛选：右侧 Filters 栏
    column_filters = [
        BooleanFilter(Job.enabled),
        OperationColumnFilter(Job.handler_path),
        RecentDateTimeFilter(Job.created_at, title="创建时间", parameter_name="created_at_recent"),
    ]

    @action(
        name="run_now",
        label="立即运行",
        confirmation_message="确认立即执行该任务？",
        add_in_list=True,
        add_in_detail=True,
    )
    async def run_now(self, request: Request):  # type: ignore[override]
        pks = request.query_params.get("pks", "").split(",")
        for pk in [p for p in pks if p]:
            execute_job.delay(job_id=pk)
        referer = request.headers.get("Referer")
        return RedirectResponse(referer or request.url_for("admin:list", identity=self.identity), status_code=303)

    async def on_model_change(self, data: dict, model: Job, is_created: bool, request) -> None:  # type: ignore[override]
        # id 必填（避免插入时触发 NOT NULL）
        raw_id = data.get("id") if is_created else (data.get("id") or getattr(model, "id", None))
        if raw_id is None or not str(raw_id).strip():
            raise ValueError("id is required")

        # handler_path 强校验：必须可 import 且继承 BaseJob
        handler_path = data.get("handler_path") if is_created else (data.get("handler_path") or model.handler_path)
        if handler_path is None or not str(handler_path).strip():
            raise ValueError("handler_path is required")
        load_job_class(str(handler_path).strip())

        # cron_expr 校验：必须是合法 cron 表达式
        cron_expr = data.get("cron_expr") if is_created else (data.get("cron_expr") or model.cron_expr)
        if cron_expr is None or not str(cron_expr).strip():
            raise ValueError("cron_expr is required")
        base = datetime.now(ZoneInfo("Asia/Shanghai"))
        itr = croniter(str(cron_expr).strip(), base)
        _ = itr.get_next(datetime)

        # public_cfg：必须是合法 JSON 对象（dict），否则直接报错阻止落库
        pcfg = data.get("public_cfg")
        if isinstance(pcfg, str):
            try:
                pcfg = json.loads(pcfg)
            except json.JSONDecodeError as e:
                raise ValueError("public_cfg must be a JSON object") from e
        if not isinstance(pcfg, dict):
            raise ValueError("public_cfg must be a JSON object")
        data["public_cfg"] = pcfg

        # secret_cfg：
        # - 创建：必须是合法 JSON 对象（dict），并且保存时必须加密落库
        # - 编辑：出于安全考虑不回显密文；若留空则保留原密文不更新；若填写则按 JSON 校验并加密覆盖
        if is_created:
            scfg = data.get("secret_cfg")
            if isinstance(scfg, str):
                try:
                    scfg = json.loads(scfg)
                except json.JSONDecodeError as e:
                    raise ValueError("secret_cfg must be a JSON object") from e
            if not isinstance(scfg, dict):
                raise ValueError("secret_cfg must be a JSON object")
            data["secret_cfg"] = encrypt_json(scfg)
        else:
            # 自定义编辑页会以 textarea 传回 secret_cfg（可能不存在或为空）
            try:
                form = await request.form()
                raw = form.get("secret_cfg")
            except Exception:
                raw = None
            raw_s = str(raw).strip() if raw is not None else ""
            if not raw_s:
                # 留空：不更新密文字段
                data.pop("secret_cfg", None)
            else:
                try:
                    scfg2 = json.loads(raw_s)
                except json.JSONDecodeError as e:
                    raise ValueError("secret_cfg must be a JSON object") from e
                if not isinstance(scfg2, dict):
                    raise ValueError("secret_cfg must be a JSON object")
                data["secret_cfg"] = encrypt_json(scfg2)


class JobLogAdmin(ModelView, model=JobLog):
    name = "任务日志"
    name_plural = "任务日志"
    icon = "fa fa-list"

    can_create = False
    can_edit = False
    can_delete = False

    # 列表更适合扫读：保留关键字段 + message（截断）
    column_list = [JobLog.id, JobLog.job_id, JobLog.status, JobLog.started_at, JobLog.finished_at, JobLog.message]
    # 默认按 started_at 倒序（最新在前）
    column_default_sort = [(JobLog.started_at, True)]
    column_details_list = [
        JobLog.id,
        JobLog.job_id,
        JobLog.status,
        JobLog.snapshot_params,
        JobLog.message,
        JobLog.traceback,
        JobLog.run_log,
        JobLog.celery_task_id,
        JobLog.attempt,
        JobLog.started_at,
        JobLog.finished_at,
    ]

    # 列表页模板：加入每行 Retry
    list_template = "joblog_list.html"
    # 为 JobLog 详情页单独指定模板（用于加入 Retry 按钮）
    details_template = "joblog_details.html"

    column_labels = {
        "id": "日志ID",
        "job_id": "任务ID",
        "status": "状态",
        "snapshot_params": "快照参数",
        "message": "消息",
        "traceback": "异常堆栈",
        "run_log": "运行日志",
        "celery_task_id": "Celery任务ID",
        "attempt": "重试次数",
        "started_at": "开始时间",
        "finished_at": "结束时间",
    }

    # 搜索：任务ID / message / celery_task_id
    column_searchable_list = [JobLog.job_id, JobLog.message, JobLog.celery_task_id]

    # 筛选：状态 / 重试次数 / 最近开始时间
    column_filters = [
        StaticValuesFilter(
            JobLog.status,
            options=(
                ("RUNNING", "运行中"),
                ("SUCCESS", "成功"),
                ("FAILURE", "失败"),
                ("RETRY", "重试"),
            ),
            title="状态",
        ),
        OperationColumnFilter(JobLog.attempt),
        RecentDateTimeFilter(JobLog.started_at, title="开始时间", parameter_name="started_at_recent"),
    ]

    column_formatters = {
        JobLog.started_at: lambda m, a: _fmt_dt_seconds(m.started_at),
        JobLog.finished_at: lambda m, a: _fmt_dt_seconds(m.finished_at),
        JobLog.message: lambda m, a: _truncate(m.message, 120),
    }

    column_formatters_detail = {
        JobLog.started_at: lambda m, a: _fmt_dt_seconds(m.started_at),
        JobLog.finished_at: lambda m, a: _fmt_dt_seconds(m.finished_at),
        JobLog.message: lambda m, a: Markup(
            "<pre style='max-height:240px;overflow:auto;white-space:pre-wrap'>"
            + (m.message or "")
            + "</pre>"
        ),
        JobLog.traceback: lambda m, a: Markup(f"<pre style='white-space:pre-wrap'>{m.traceback or ''}</pre>"),
        JobLog.run_log: lambda m, a: Markup(
            "<pre style='max-height:480px;overflow:auto;white-space:pre-wrap'>"
            + (m.run_log or "")
            + "</pre>"
        ),
        JobLog.snapshot_params: lambda m, a: Markup(
            "<pre style='white-space:pre-wrap'>"
            + json.dumps(m.snapshot_params or {}, ensure_ascii=False, indent=2, sort_keys=True)
            + "</pre>"
        ),
    }