"""OA 审批人解析（不读 sys_role；职位成员走 sys_user_post）"""
from __future__ import annotations

from typing import Any, Dict, List, Optional, Tuple

from sqlalchemy.orm import Session

from app.crud import user as user_crud
from app.models.models import SysDept, SysUser


class AssigneeResolveError(ValueError):
    """审批人解析失败"""


VALID_ASSIGNEE_TYPES = frozenset(
    {
        "users",
        "posts",
        "dept_leader",
        "direct_supervisor",
        "initiator_select",
    }
)


def normalize_cc_assignee_types(assignee_config: Optional[Dict[str, Any]]) -> List[str]:
    cfg = assignee_config or {}
    raw = cfg.get("assigneeTypes") or cfg.get("assignee_types")
    out: List[str] = []
    seen = set()
    if isinstance(raw, list) and raw:
        for item in raw:
            t = str(item or "").strip()
            if t in VALID_ASSIGNEE_TYPES and t not in seen:
                seen.add(t)
                out.append(t)
        return out
    single = (cfg.get("assigneeType") or cfg.get("assignee_type") or "").strip()
    if single in VALID_ASSIGNEE_TYPES:
        return [single]
    return []


def resolve_cc_assignees(
    db: Session,
    *,
    tenant_no: str,
    assignee_config: Dict[str, Any],
    initiator_user_id: str,
    initiator_dept_id: Optional[str] = None,
    advanced: Optional[Dict[str, Any]] = None,
    initiator_select_user_ids: Optional[List[str]] = None,
) -> Tuple[List[str], Dict[str, Any]]:
    """抄送多策略软并集：单策略失败/空则跳过；全部无人返回 []，不抛错。"""
    cfg = assignee_config or {}
    types = normalize_cc_assignee_types(cfg)
    merged: List[str] = []
    seen = set()
    sources: List[str] = []
    skipped: List[Dict[str, str]] = []

    for t in types:
        single_cfg = {**cfg, "assigneeType": t}
        try:
            users, meta = resolve_assignees(
                db,
                tenant_no=tenant_no,
                assignee_config=single_cfg,
                initiator_user_id=initiator_user_id,
                initiator_dept_id=initiator_dept_id,
                advanced=advanced,
                initiator_select_user_ids=initiator_select_user_ids,
            )
        except AssigneeResolveError as e:
            skipped.append({"type": t, "reason": str(e)})
            continue
        if not users:
            skipped.append({"type": t, "reason": "empty"})
            continue
        src = str((meta or {}).get("resolve_source") or t)
        sources.append(src)
        for uid in users:
            if uid and uid not in seen:
                seen.add(uid)
                merged.append(uid)

    if len(sources) == 1:
        resolve_source = sources[0]
    elif len(sources) > 1:
        resolve_source = "multi"
    else:
        resolve_source = ""

    return merged, {
        "resolve_source": resolve_source,
        "sources": sources,
        "skipped": skipped,
        "assigneeTypes": types,
    }


def _active_user_id(db: Session, user_id: Optional[str], tenant_no: str) -> Optional[str]:
    uid = (user_id or "").strip()
    if not uid:
        return None
    u = (
        db.query(SysUser)
        .filter(
            SysUser.id == uid,
            SysUser.tenant_no == tenant_no,
            SysUser.del_flag == 0,
            SysUser.status == "1",
        )
        .first()
    )
    return u.id if u else None


def resolve_dept_leader(
    db: Session, *, tenant_no: str, initiator_dept_id: Optional[str]
) -> Tuple[List[str], Dict[str, Any]]:
    dept_id = (initiator_dept_id or "").strip()
    if not dept_id:
        raise AssigneeResolveError("发起人部门为空，无法解析部门负责人")
    dept = (
        db.query(SysDept)
        .filter(SysDept.id == dept_id, SysDept.tenant_no == tenant_no, SysDept.del_flag == 0)
        .first()
    )
    if not dept:
        raise AssigneeResolveError("发起人部门不存在")
    leader_uid = _active_user_id(db, getattr(dept, "leader_user_id", None), tenant_no)
    if not leader_uid:
        raise AssigneeResolveError("部门负责人未配置或用户无效，请在组织管理中维护负责人")
    return [leader_uid], {"resolve_source": "dept_leader"}


def resolve_direct_supervisor(
    db: Session,
    *,
    tenant_no: str,
    initiator_user_id: str,
    initiator_dept_id: Optional[str],
    fallback_to_dept_leader: bool = True,
) -> Tuple[List[str], Dict[str, Any]]:
    initiator = (
        db.query(SysUser)
        .filter(
            SysUser.id == initiator_user_id,
            SysUser.tenant_no == tenant_no,
            SysUser.del_flag == 0,
        )
        .first()
    )
    if not initiator:
        raise AssigneeResolveError("发起人不存在")
    supervisor_uid = _active_user_id(
        db, getattr(initiator, "supervisor_user_id", None), tenant_no
    )
    if supervisor_uid:
        # 允许主管配置为本人（如部门经理），由高级设置 autoPassWhenApproverIsInitiator 决定是否自动通过
        return [supervisor_uid], {"resolve_source": "direct_supervisor"}
    if fallback_to_dept_leader:
        users, meta = resolve_dept_leader(
            db, tenant_no=tenant_no, initiator_dept_id=initiator_dept_id or initiator.dept_id
        )
        meta = {**meta, "resolve_source": "supervisor_fallback_dept_leader"}
        return users, meta
    raise AssigneeResolveError("未配置直属主管，且未开启回退部门负责人")


def resolve_assignees(
    db: Session,
    *,
    tenant_no: str,
    assignee_config: Dict[str, Any],
    initiator_user_id: str,
    initiator_dept_id: Optional[str] = None,
    advanced: Optional[Dict[str, Any]] = None,
    initiator_select_user_ids: Optional[List[str]] = None,
) -> Tuple[List[str], Dict[str, Any]]:
    """
    按节点 approverConfig 解析处理人。
    assigneeType: users | posts | dept_leader | direct_supervisor | initiator_select
    """
    cfg = assignee_config or {}
    assignee_type = (cfg.get("assigneeType") or cfg.get("assignee_type") or "").strip()
    advanced = advanced or {}
    fallback = advanced.get("supervisorFallbackToDeptLeader", True)
    if isinstance(fallback, str):
        fallback = fallback.lower() in ("1", "true", "yes")

    if assignee_type == "users":
        ids = cfg.get("userIds") or cfg.get("user_ids") or []
        out: List[str] = []
        seen = set()
        for uid in ids:
            real = _active_user_id(db, uid, tenant_no)
            if real and real not in seen:
                seen.add(real)
                out.append(real)
        if not out:
            raise AssigneeResolveError("指定成员为空或均无效")
        return out, {"resolve_source": "users"}

    if assignee_type == "posts":
        post_ids = cfg.get("postIds") or cfg.get("post_ids") or []
        users = user_crud.list_user_ids_bound_to_posts(db, list(post_ids), tenant_no)
        out = []
        seen = set()
        for uid in users:
            real = _active_user_id(db, uid, tenant_no)
            if real and real not in seen:
                seen.add(real)
                out.append(real)
        if not out:
            raise AssigneeResolveError("职位成员为空或均无效")
        return out, {"resolve_source": "posts"}

    if assignee_type == "dept_leader":
        return resolve_dept_leader(
            db, tenant_no=tenant_no, initiator_dept_id=initiator_dept_id
        )

    if assignee_type == "direct_supervisor":
        return resolve_direct_supervisor(
            db,
            tenant_no=tenant_no,
            initiator_user_id=initiator_user_id,
            initiator_dept_id=initiator_dept_id,
            fallback_to_dept_leader=bool(fallback),
        )

    if assignee_type == "initiator_select":
        ids = initiator_select_user_ids or cfg.get("userIds") or []
        out = []
        seen = set()
        for uid in ids:
            real = _active_user_id(db, uid, tenant_no)
            if real and real not in seen:
                seen.add(real)
                out.append(real)
        if not out:
            raise AssigneeResolveError("发起人未选择审批人")
        return out, {"resolve_source": "initiator_select"}

    raise AssigneeResolveError(f"不支持的审批人类型: {assignee_type or '(空)'}")