"""scheduler 限界上下文用例 DTO 定义。

包含：
- 任务管理 Input/Output DTO（CRUD / 暂停 / 恢复 / 手动触发）
- 执行日志 Input/Output DTO（列表查询）
- 可观测性 Output DTO（handler 摘要 / 状态计数 / 即将执行 / 健康检查）
- 运维恢复 Input/Output DTO（回收僵尸执行）

字段约束（``min_length`` / ``max_length`` / ``pattern`` / ``ge`` / ``le``）在 DTO 中
声明，由 Pydantic 在构造时校验。DateTime 字段在 Output DTO 中以 ISO 格式字符串
表达（``str | None``），由 Router 层在序列化时格式化。JSON 字段（如 ``payload``）
使用 ``dict[str, Any]``。

对齐 ``external_systems/use_cases/dto/system.py`` 写法。
"""

from __future__ import annotations

from typing import Any

from pydantic import BaseModel, ConfigDict, Field

# ---------------------------------------------------------------------------
# 任务管理 DTO
# ---------------------------------------------------------------------------


class CreateTaskInput(BaseModel):
    """创建定时任务输入 DTO。

    ``schedule_kind`` 决定调度类型：``cron`` 必填 ``cron_expression``，
    ``at`` 必填 ``run_at``。``task_id`` 由系统生成（UUID4），不接受客户端指定。
    """

    model_config = ConfigDict(frozen=True)

    handler_name: str = Field(
        ...,
        min_length=1,
        max_length=128,
        pattern=r"^[a-zA-Z_][a-zA-Z0-9_-]*$",
        description="handler 标识，与 TaskHandler.name 引用一致",
    )
    owner_scope: str = Field(
        ...,
        min_length=1,
        max_length=64,
        description="任务归属范围：system（平台级）/ business（业务方）",
    )
    owner_id: str = Field(
        ...,
        min_length=1,
        max_length=128,
        description="业务方标识，格式如 channel_type:account_id",
    )
    schedule_kind: str = Field(
        ...,
        pattern=r"^(cron|at)$",
        description="调度类型：cron（周期）/ at（一次性）",
    )
    cron_expression: str | None = Field(
        default=None,
        max_length=128,
        description="cron 表达式（标准 5 字段），schedule_kind=cron 时必填",
    )
    run_at: str | None = Field(
        default=None,
        description="一次性执行时间（ISO 格式字符串），schedule_kind=at 时必填且须为未来时间",
    )
    tz: str = Field(
        default="Asia/Shanghai",
        max_length=64,
        description="时区标识，如 Asia/Shanghai",
    )
    payload: dict[str, Any] = Field(
        default_factory=dict,
        description="任务执行时传给 handler 的参数，序列化后不超过 64KB",
    )
    enabled: bool = Field(default=True, description="是否启用")
    delete_after_run: bool = Field(
        default=False,
        description="一次性任务执行完成后是否自动删除（schedule_kind=at 时有意义）",
    )
    block_strategy: str = Field(
        default="discard_later",
        pattern=r"^(discard_later)$",
        description="阻塞策略：discard_later（存在 running 执行时丢弃本次触发）",
    )
    created_by: str = Field(default="system", max_length=128)


class UpdateTaskInput(BaseModel):
    """更新定时任务输入 DTO。

    允许更新字段（PRD §FR-ST-05）：``cron_expression`` / ``run_at`` / ``tz`` /
    ``payload`` / ``enabled`` / ``delete_after_run`` / ``owner_scope`` / ``owner_id``。
    ``schedule_kind`` 与 ``handler_name`` 不可修改。修改 ``cron_expression`` 时
    由用例层重新计算 ``next_run_at`` 与 ``stagger_seconds``。
    """

    model_config = ConfigDict(frozen=True)

    task_id: str = Field(
        ...,
        min_length=1,
        max_length=64,
        description="任务标识（UUID4）",
    )
    cron_expression: str | None = Field(
        default=None,
        max_length=128,
        description="新的 cron 表达式，传入时重算 next_run_at 与 stagger_seconds",
    )
    run_at: str | None = Field(
        default=None,
        description="新的一次性执行时间（ISO 格式字符串）",
    )
    tz: str | None = Field(
        default=None,
        max_length=64,
        description="新的时区标识",
    )
    payload: dict[str, Any] | None = Field(
        default=None,
        description="新的 payload，传入时整体替换",
    )
    enabled: bool | None = Field(default=None, description="是否启用")
    delete_after_run: bool | None = Field(
        default=None,
        description="一次性任务执行完成后是否自动删除",
    )
    owner_scope: str | None = Field(
        default=None,
        min_length=1,
        max_length=64,
    )
    owner_id: str | None = Field(
        default=None,
        min_length=1,
        max_length=128,
    )
    updated_by: str | None = Field(default=None, max_length=128)


class GetTaskInput(BaseModel):
    """获取任务详情输入 DTO。"""

    model_config = ConfigDict(frozen=True)

    task_id: str = Field(..., min_length=1, max_length=64)


class DeleteTaskInput(BaseModel):
    """删除任务输入 DTO（软删除）。"""

    model_config = ConfigDict(frozen=True)

    task_id: str = Field(..., min_length=1, max_length=64)
    updated_by: str | None = Field(default=None, max_length=128)


class PauseTaskInput(BaseModel):
    """暂停任务输入 DTO。"""

    model_config = ConfigDict(frozen=True)

    task_id: str = Field(..., min_length=1, max_length=64)
    updated_by: str | None = Field(default=None, max_length=128)


class ResumeTaskInput(BaseModel):
    """恢复任务输入 DTO。

    对 ``status=paused`` 任务调用 ``pause`` 的逆操作；对 ``status=dead_letter``
    任务重置 ``consecutive_errors`` / ``last_error`` 并恢复为 ``active``。
    """

    model_config = ConfigDict(frozen=True)

    task_id: str = Field(..., min_length=1, max_length=64)
    updated_by: str | None = Field(default=None, max_length=128)


class TriggerTaskInput(BaseModel):
    """手动触发任务输入 DTO。

    ``triggered_by`` 标识触发来源（``auto`` / ``manual``），手动触发不入正常
    ``next_run_at`` 流，不影响下一次自动执行。死信任务允许手动触发用于验证
    handler 是否已修复，但不重置 ``status``。
    """

    model_config = ConfigDict(frozen=True)

    task_id: str = Field(..., min_length=1, max_length=64)
    triggered_by: str = Field(
        default="manual",
        pattern=r"^(auto|manual)$",
        description="触发来源：auto（tick 自动）/ manual（管理员手动）",
    )
    payload: dict[str, Any] | None = Field(
        default=None,
        description="可选 payload 覆盖，None 时使用任务定义中的 payload",
    )


class TaskOutput(BaseModel):
    """任务输出 DTO。字段与 ``ScheduledTask`` dataclass 对齐。

    DateTime 字段（``run_at`` / ``last_run_at`` / ``next_run_at`` / ``created_at``
    / ``updated_at`` / ``deleted_at``）以 ISO 格式字符串表达，由 Router 层格式化。
    """

    model_config = ConfigDict(frozen=True)

    task_id: str
    handler_name: str
    owner_scope: str
    owner_id: str
    schedule_kind: str
    cron_expression: str | None = None
    run_at: str | None = None
    tz: str = "Asia/Shanghai"
    payload: dict[str, Any] = Field(default_factory=dict)
    enabled: bool = True
    delete_after_run: bool = False
    block_strategy: str = "discard_later"
    stagger_seconds: int | None = None
    consecutive_errors: int = 0
    status: str = "active"
    last_run_at: str | None = None
    next_run_at: str | None = None
    last_error: str | None = None
    created_by: str = "system"
    updated_by: str | None = None
    id: int | None = None
    created_at: str | None = None
    updated_at: str | None = None
    is_deleted: int = 0
    deleted_at: str | None = None


class ListTasksInput(BaseModel):
    """列出任务输入 DTO。

    过滤字段对齐 PRD §FR-ST-05 列表 API 查询参数与仓储层 ``list`` 方法签名。
    """

    model_config = ConfigDict(frozen=True)

    page: int = Field(default=1, ge=1, description="页码，从 1 开始")
    page_size: int = Field(default=20, ge=1, le=100, description="每页条数，最大 100")
    owner_scope: str | None = Field(default=None, max_length=64)
    owner_id: str | None = Field(default=None, max_length=128)
    handler_name: str | None = Field(default=None, max_length=128)
    enabled: bool | None = None
    status: str | None = Field(
        default=None,
        pattern=r"^(active|paused|dead_letter)$",
        description="任务状态过滤",
    )


class ListTasksOutput(BaseModel):
    """列出任务输出 DTO。"""

    model_config = ConfigDict(frozen=True)

    items: list[TaskOutput] = Field(default_factory=list)
    total: int = 0
    page: int = 1
    page_size: int = 20


# ---------------------------------------------------------------------------
# 执行日志 DTO
# ---------------------------------------------------------------------------


class ListRunLogsInput(BaseModel):
    """列出执行日志输入 DTO。

    ``task_id`` 必填，按任务维度查询执行明细。``status`` / ``start_date`` /
    ``end_date`` 为可选过滤字段，``start_date`` / ``end_date`` 为 ISO 格式字符串，
    由用例层解析为 ``datetime`` 后传入仓储层。
    """

    model_config = ConfigDict(frozen=True)

    task_id: str = Field(..., min_length=1, max_length=64)
    page: int = Field(default=1, ge=1)
    page_size: int = Field(default=20, ge=1, le=100)
    status: str | None = Field(
        default=None,
        pattern=r"^(running|success|failure|timeout|skipped)$",
        description="执行状态过滤",
    )
    start_date: str | None = Field(
        default=None,
        description="起始时间（ISO 格式字符串），按 started_at 过滤",
    )
    end_date: str | None = Field(
        default=None,
        description="截止时间（ISO 格式字符串），按 started_at 过滤",
    )


class GetRunLogInput(BaseModel):
    """获取执行日志详情输入 DTO。"""

    model_config = ConfigDict(frozen=True)

    run_id: str = Field(..., min_length=1, max_length=64)


class RunLogOutput(BaseModel):
    """执行日志输出 DTO。字段与 ``ScheduledTaskRunLog`` dataclass 对齐。

    DateTime 字段（``started_at`` / ``finished_at`` / ``created_at`` /
    ``updated_at`` / ``deleted_at``）以 ISO 格式字符串表达。
    """

    model_config = ConfigDict(frozen=True)

    task_id: str
    run_id: str
    triggered_by: str = "auto"
    status: str = "running"
    error_message: str | None = None
    output: dict[str, Any] | None = None
    started_at: str | None = None
    finished_at: str | None = None
    created_by: str = "system"
    updated_by: str | None = None
    id: int | None = None
    created_at: str | None = None
    updated_at: str | None = None
    is_deleted: int = 0
    deleted_at: str | None = None


class ListRunLogsOutput(BaseModel):
    """列出执行日志输出 DTO。"""

    model_config = ConfigDict(frozen=True)

    items: list[RunLogOutput] = Field(default_factory=list)
    total: int = 0
    page: int = 1
    page_size: int = 20


class ListAllRunLogsInput(BaseModel):
    """跨任务执行日志查询输入 DTO。

    ``task_id`` 与 ``status`` 均可选，但不可同时为空（由用例层校验），
    避免无过滤的全表扫描。``start_date`` / ``end_date`` 为 ISO 格式字符串，
    由用例层解析为 ``datetime`` 后传入仓储层。
    """

    model_config = ConfigDict(frozen=True)

    page: int = Field(default=1, ge=1)
    page_size: int = Field(default=20, ge=1, le=100)
    status: str | None = Field(
        default=None,
        pattern=r"^(running|success|failure|timeout|skipped)$",
        description="执行状态过滤",
    )
    start_date: str | None = Field(
        default=None,
        description="起始时间（ISO 格式字符串），按 started_at 过滤",
    )
    end_date: str | None = Field(
        default=None,
        description="截止时间（ISO 格式字符串），按 started_at 过滤",
    )
    task_id: str | None = Field(default=None, min_length=1, max_length=64)


# ---------------------------------------------------------------------------
# 可观测性 DTO
# ---------------------------------------------------------------------------


class HandlerSummaryOutput(BaseModel):
    """handler 聚合摘要输出 DTO。

    对齐 PRD §FR-ST-05 ``GET /handlers`` 端点响应字段，走 DB 聚合
    （``task_repo.list_handler_summary``），不查内存注册表。
    """

    model_config = ConfigDict(frozen=True)

    handler_name: str
    description: str = ""
    task_count: int = 0
    active_task_count: int = 0
    last_active_at: str | None = None


class ListHandlerSummaryOutput(BaseModel):
    """handler 聚合摘要列表输出 DTO。"""

    model_config = ConfigDict(frozen=True)

    items: list[HandlerSummaryOutput] = Field(default_factory=list)


class CountByStatusOutput(BaseModel):
    """任务状态计数输出 DTO。

    对齐 PRD §FR-ST-07 健康检查与指标需求，按 ``status`` 维度统计任务数。
    """

    model_config = ConfigDict(frozen=True)

    active: int = 0
    paused: int = 0
    dead_letter: int = 0


class ListUpcomingInput(BaseModel):
    """即将执行任务查询输入 DTO。

    对齐 PRD §FR-ST-09 统计查询，按 ``next_run_at`` 升序返回即将执行的任务列表。
    """

    model_config = ConfigDict(frozen=True)

    limit: int = Field(default=100, ge=1, le=1000, description="返回条数上限")
    handler_name: str | None = Field(default=None, max_length=128)


class ListUpcomingOutput(BaseModel):
    """即将执行任务列表输出 DTO。"""

    model_config = ConfigDict(frozen=True)

    items: list[TaskOutput] = Field(default_factory=list)


class GetHealthOutput(BaseModel):
    """调度器健康检查输出 DTO。

    对齐 PRD §FR-ST-07 健康检查端点响应：``status`` 表示 worker 是否在最近
    5 分钟内执行 tick；``last_tick_at`` 为最近 tick 时间；``active_task_count``
    / ``dead_letter_count`` / ``running_count`` 为关键状态计数。
    """

    model_config = ConfigDict(frozen=True)

    status: str = Field(
        default="healthy",
        pattern=r"^(healthy|unhealthy)$",
        description="健康状态：healthy（最近 5 分钟内有 tick）/ unhealthy",
    )
    last_tick_at: str | None = Field(default=None, description="最近 tick 时间（ISO 格式字符串）")
    active_task_count: int = 0
    dead_letter_count: int = 0
    running_count: int = 0


# ---------------------------------------------------------------------------
# 日聚合统计 DTO
# ---------------------------------------------------------------------------


class ListDailyStatsInput(BaseModel):
    """日聚合统计查询输入 DTO。

    ``start_date`` / ``end_date`` 为 ISO 日期字符串（``YYYY-MM-DD``），由用例层
    解析为 ``date`` 后传入仓储层。日期范围上限 90 天。
    """

    model_config = ConfigDict(frozen=True)

    start_date: str = Field(..., description="ISO 日期 YYYY-MM-DD")
    end_date: str = Field(..., description="ISO 日期 YYYY-MM-DD")
    handler_name: str | None = Field(default=None, max_length=128)


class DailyStatOutput(BaseModel):
    """日聚合统计输出 DTO。字段对齐 ``DailyStat`` dataclass，补充派生字段。

    ``total_count`` / ``success_rate`` 为派生字段，由 mapper 计算：
    ``total_count = success_count + failure_count + timeout_count``，
    ``success_rate = success_count / total_count if total_count > 0 else 0.0``。
    """

    model_config = ConfigDict(frozen=True)

    stat_date: str
    handler_name: str
    success_count: int = 0
    failure_count: int = 0
    timeout_count: int = 0
    dead_letter_count: int = 0
    total_count: int = 0
    success_rate: float = 0.0


class ListDailyStatsOutput(BaseModel):
    """日聚合统计列表输出 DTO。"""

    model_config = ConfigDict(frozen=True)

    items: list[DailyStatOutput] = Field(default_factory=list)


# ---------------------------------------------------------------------------
# 运维恢复 DTO
# ---------------------------------------------------------------------------


class ReclaimStaleRunsInput(BaseModel):
    """回收僵尸执行输入 DTO。

    用于 scheduler 重启后回收 ``status=running`` 但实际已超时的执行记录，
    将其标记为 ``failure`` 并写入回收错误信息。``timeout_seconds`` 为可选参数，
    未传入时由用例层从配置取默认值。
    """

    model_config = ConfigDict(frozen=True)

    timeout_seconds: int | None = Field(
        default=None,
        ge=1,
        description="执行超时阈值（秒），None 时从配置取默认值",
    )


class ReclaimStaleRunsOutput(BaseModel):
    """回收僵尸执行输出 DTO。"""

    model_config = ConfigDict(frozen=True)

    reclaimed_count: int = 0


# ---------------------------------------------------------------------------
# 任务回收站 DTO
# ---------------------------------------------------------------------------


class ListDeletedTasksInput(BaseModel):
    """列出已删除任务（回收站）输入 DTO。

    ``start_date`` / ``end_date`` 为 ISO 格式字符串，由用例层解析为 ``datetime``
    后按 ``deleted_at`` 过滤。
    """

    model_config = ConfigDict(frozen=True)

    page: int = Field(default=1, ge=1)
    page_size: int = Field(default=20, ge=1, le=100)
    start_date: str | None = Field(
        default=None,
        description="起始时间（ISO 格式字符串），按 deleted_at 过滤",
    )
    end_date: str | None = Field(
        default=None,
        description="截止时间（ISO 格式字符串），按 deleted_at 过滤",
    )


class RestoreTaskInput(BaseModel):
    """恢复已删除任务输入 DTO。"""

    model_config = ConfigDict(frozen=True)

    task_id: str = Field(..., min_length=1, max_length=64)
    updated_by: str | None = Field(default=None, max_length=128)


class HardDeleteTaskInput(BaseModel):
    """硬删除任务输入 DTO。"""

    model_config = ConfigDict(frozen=True)

    task_id: str = Field(..., min_length=1, max_length=64)
    updated_by: str | None = Field(default=None, max_length=128)