"""GitHub ID 自助修改的 HTTP 面。

一个路由文件承载两侧,因为它们是同一条链路的两端,而**两端都不是按角色
判的**:提交按「是不是本人」,确认按「是不是这个人的 HR Ops」——后者是
数据驱动的责任,与邮件组 owner 同构。放进 ``router.py``(按
``can_manage_github_org`` 收口的管理面)会让 HR Ops 拿不到自己的队列;
放进 ``self_router.py`` 又会让「审批别人的单子」出现在一个语义是「我自己
的东西」的前缀下。

``_leaver_runtime_gate`` 挂在整个路由上:待离职的人既不该提新单子,也不
该再做人事确认。服务层另有同一道闸 —— MCP 工具直接调服务,不经过这里。
"""
from __future__ import annotations

from fastapi import APIRouter, Depends, Request
from pydantic import BaseModel, Field
from sqlalchemy.ext.asyncio import AsyncSession

from app.auth.models import AuthUser
from app.core.database import get_db
from app.core.dependencies import get_current_user
from app.core.dependencies import (
    require_active_employee_for_mutations as _leaver_runtime_gate,
)
from app.core.exceptions import NotFoundError
from app.core.response import success_response
from app.identity.person_models import IdentityPerson

from . import constants as const
from .handle_change_service import GithubIdChangeService

router = APIRouter(
    prefix="/api/v1/me/github-id",
    tags=["github-id-change"],
    dependencies=[Depends(_leaver_runtime_gate)],
)


class SubmitBody(BaseModel):
    # 200 而不是 39:允许粘一整条个人主页链接,归一化在校验器里做。在这里
    # 卡 39 会让一个能被正确解析的输入在到达归一化之前就被 422 掉。
    github_id: str = Field(min_length=1, max_length=200)
    reason: str | None = Field(
        default=None, max_length=const.HANDLE_CHANGE_REASON_MAX_LEN,
    )


class DecideBody(BaseModel):
    decision: str = Field(pattern="^(approve|reject)$")
    note: str | None = Field(
        default=None, max_length=const.HANDLE_CHANGE_NOTE_MAX_LEN,
    )


async def _person(db: AsyncSession, user: AuthUser) -> IdentityPerson:
    row = await db.get(IdentityPerson, user.id)
    if row is None:
        raise NotFoundError("IdentityPerson", str(user.id))
    return row


def _roles(user: AuthUser) -> list[str]:
    """角色取自 ``get_current_user`` 返回的对象,而不是 ``_person()`` 那一行。

    两者**目前是同一个 ORM 实例** —— ``get_current_user`` 依赖的也是
    ``get_db``,所以 ``db.get(IdentityPerson, user.id)`` 命中身份映射,
    ``X-View-Role`` 的收窄(``_role_names_override``,写在实例的
    ``__dict__`` 上)照样带着。所以这不是在修一个现存的泄漏。

    它是在**不依赖那个巧合**:收窄的载体按设计就是这个依赖的返回值,而
    「重新查出来的行恰好是同一个对象」是 session 作用域的实现细节。哪天
    鉴权换成自己的 session(PAT 路径、或者把用户加载挪进中间件),那个
    别名关系就没了,而按角色收口的地方会静默地开始看到未收窄的角色集。
    """
    return list(user.role_names or [])


def _trace(request: Request) -> str:
    return str(getattr(request.state, "trace_id", "") or "")


# ── 本人 ──────────────────────────────────────────────────────────


@router.get("")
async def get_my_github_id(
    request: Request,
    user: AuthUser = Depends(get_current_user),
    db: AsyncSession = Depends(get_db),
):
    """当前值 + 在途单 —— 个人设置页一次调用拿全。

    和 ``list_requestable_orgs`` 同一个道理:界面上「当前是什么」和「有没有
    在审」必须一起显示,分两次调用的那点时间差正好够渲染出一个不该有的
    「修改」按钮。
    """
    person = await _person(db, user)
    data = await GithubIdChangeService(db).get_state(person)
    return success_response(data, request=request)


@router.get("/requests")
async def list_my_requests(
    request: Request,
    user: AuthUser = Depends(get_current_user),
    db: AsyncSession = Depends(get_db),
):
    person = await _person(db, user)
    data = await GithubIdChangeService(db).list_mine(person)
    return success_response(data, request=request)


@router.post("/requests", status_code=201)
async def submit_request(
    body: SubmitBody,
    request: Request,
    user: AuthUser = Depends(get_current_user),
    db: AsyncSession = Depends(get_db),
):
    person = await _person(db, user)
    svc = GithubIdChangeService(db)
    row = await svc.submit(
        requester=person,
        github_id=body.github_id,
        reason=body.reason,
        trace_id=_trace(request),
    )
    data = await svc.serialize(row)
    await db.commit()
    return success_response(data, request=request)


@router.post("/requests/{request_id}/cancel")
async def cancel_request(
    request_id: str,
    request: Request,
    user: AuthUser = Depends(get_current_user),
    db: AsyncSession = Depends(get_db),
):
    person = await _person(db, user)
    svc = GithubIdChangeService(db)
    row = await svc.cancel(
        request_id=request_id, requester=person, trace_id=_trace(request),
    )
    data = await svc.serialize(row)
    await db.commit()
    return success_response(data, request=request)


# ── 审批人 ────────────────────────────────────────────────────────


@router.get("/approvals")
async def list_pending_approvals(
    request: Request,
    user: AuthUser = Depends(get_current_user),
    db: AsyncSession = Depends(get_db),
):
    """等我确认的单子。没有角色闸 —— 是不是审批人由数据决定。"""
    person = await _person(db, user)
    data = await GithubIdChangeService(db).list_pending_for_approver(
        person=person, role_names=_roles(user),
    )
    return success_response(data, request=request)


@router.post("/approvals/{request_id}/decide")
async def decide_request(
    request_id: str,
    body: DecideBody,
    request: Request,
    user: AuthUser = Depends(get_current_user),
    db: AsyncSession = Depends(get_db),
):
    person = await _person(db, user)
    svc = GithubIdChangeService(db)
    row, requester = await svc.decide(
        request_id=request_id,
        actor=person,
        role_names=_roles(user),
        decision=body.decision,
        note=body.note,
        trace_id=_trace(request),
    )
    data = await svc.serialize(row)
    await db.commit()
    # commit 之后才广播:``enqueue_person_sync`` 开的是自己的 session,
    # 在 commit 之前调它,它读到的还是旧 handle,于是把旧值推去飞书。
    if row.status == const.HANDLE_CHANGE_STATUS_APPROVED:
        GithubIdChangeService.broadcast_after_commit(str(requester.id))
    return success_response(data, request=request)