"""运输计划 - 证书 CRUD 与到期扫描"""
from __future__ import annotations

from datetime import date
from typing import Optional

from fastapi import HTTPException
from sqlalchemy.orm import Session

from app.core.utils import generate_uuid
from app.models.pl_models import PlCert, PlDocumentReminder, PlPersonnel, PlVehicle
from app.schemas.pl.base_data import CertRead, CertRow


def list_owner_certs(
    db: Session, tenant_no: str, owner_type: str, owner_id: str
) -> list[PlCert]:
    return (
        db.query(PlCert)
        .filter(
            PlCert.tenant_no == tenant_no,
            PlCert.owner_type == owner_type,
            PlCert.owner_id == owner_id,
            PlCert.del_flag == 0,
        )
        .order_by(PlCert.order_num.asc(), PlCert.create_time.asc())
        .all()
    )


def list_owner_certs_batch(
    db: Session, tenant_no: str, owner_type: str, owner_ids: list[str]
) -> dict[str, list[PlCert]]:
    if not owner_ids:
        return {}
    rows = (
        db.query(PlCert)
        .filter(
            PlCert.tenant_no == tenant_no,
            PlCert.owner_type == owner_type,
            PlCert.owner_id.in_(owner_ids),
            PlCert.del_flag == 0,
        )
        .order_by(PlCert.order_num.asc(), PlCert.create_time.asc())
        .all()
    )
    grouped: dict[str, list[PlCert]] = {}
    for cert in rows:
        grouped.setdefault(cert.owner_id, []).append(cert)
    return grouped


def certs_to_read(certs: list[PlCert]) -> list[CertRead]:
    return [
        CertRead(
            id=c.id,
            cert_id=c.id,
            vehicle_part=c.vehicle_part,
            cert_name=c.cert_name,
            cert_no=c.cert_no,
            expire_date=c.expire_date,
            remind_days=c.remind_days,
            attachment_urls=c.attachment_urls,
            owner_type=c.owner_type,
            owner_id=c.owner_id,
            status=c.status,
            tenant_no=c.tenant_no,
            create_time=c.create_time,
            update_time=c.update_time,
        )
        for c in certs
    ]


def _normalize_cert_row(row: CertRow | dict) -> CertRow:
    if isinstance(row, CertRow):
        return row
    return CertRow.model_validate(row)


def save_owner_certs(
    db: Session,
    owner_type: str,
    owner_id: str,
    cert_rows: list[CertRow | dict],
    tenant_no: str,
    *,
    user_id: str,
    dept_id: str,
) -> None:
    """按 ID 差量保存；旧请求仅复用唯一业务键，遗漏旧证软删。"""
    existing = db.query(PlCert).filter(
        PlCert.tenant_no == tenant_no,
        PlCert.owner_type == owner_type,
        PlCert.owner_id == owner_id,
        PlCert.del_flag == 0,
    ).populate_existing().with_for_update().all()
    existing_map = {c.id: c for c in existing}
    rows = [_normalize_cert_row(row) for row in cert_rows]
    explicit_ids: set[str] = set()
    for row in rows:
        cert_id = (row.cert_id or "").strip()
        if cert_id:
            if cert_id in explicit_ids or cert_id not in existing_map:
                raise HTTPException(400, "证书ID重复或不属于当前主体")
            explicit_ids.add(cert_id)

    def business_key(row):
        return tuple((getattr(row, key) or "").strip() for key in (
            "vehicle_part", "cert_name", "cert_no"
        ))

    by_key = {}
    for cert in existing:
        if cert.id not in explicit_ids:
            by_key.setdefault(business_key(cert), []).append(cert)
    prepared = []
    legacy_keys = set()
    for row in rows:
        cert_id = (row.cert_id or "").strip()
        if cert_id:
            cert = existing_map[cert_id]
        else:
            key = business_key(row)
            matches = by_key.get(key, [])
            if key in legacy_keys or len(matches) > 1:
                raise HTTPException(400, "证书业务键重复或不唯一，请刷新后使用证书ID保存")
            legacy_keys.add(key)
            cert = matches[0] if matches else None
        prepared.append((row, cert))

    keep_ids: set[str] = set()
    for idx, (row, cert) in enumerate(prepared):
        if cert is not None:
            for field in (
                "vehicle_part", "cert_name", "cert_no", "expire_date",
                "remind_days", "attachment_urls",
            ):
                # A submitted certificate is a full form row; UI-cleared optional
                # fields are omitted by JSON and use the schema's empty defaults.
                setattr(cert, field, getattr(row, field))
            cert.order_num = idx
            cert.update_by = user_id
            keep_ids.add(cert.id)
        else:
            cert = PlCert(
                id=generate_uuid(),
                tenant_no=tenant_no,
                owner_type=owner_type,
                owner_id=owner_id,
                vehicle_part=row.vehicle_part,
                cert_name=row.cert_name,
                cert_no=row.cert_no,
                expire_date=row.expire_date,
                remind_days=row.remind_days,
                attachment_urls=row.attachment_urls,
                status="valid",
                order_num=idx,
                create_by=user_id,
                create_dept_id=dept_id,
            )
            db.add(cert)
            db.flush()
            keep_ids.add(cert.id)

    for cert in existing:
        if cert.id not in keep_ids:
            cert.del_flag = 1
            cert.update_by = user_id

    scan_cert_expiry(db, tenant_no)


def nearest_expire_date(
    db: Session, tenant_no: str, owner_type: str, owner_id: str
) -> Optional[date]:
    row = (
        db.query(PlCert.expire_date)
        .filter(
            PlCert.tenant_no == tenant_no,
            PlCert.owner_type == owner_type,
            PlCert.owner_id == owner_id,
            PlCert.del_flag == 0,
            PlCert.expire_date.isnot(None),
        )
        .order_by(PlCert.expire_date.asc())
        .first()
    )
    return row[0] if row else None


def _resolve_owner_label(
    db: Session, tenant_no: str, owner_type: str, owner_id: str
) -> str:
    if owner_type == "vehicle":
        vehicle = (
            db.query(PlVehicle)
            .filter(
                PlVehicle.id == owner_id,
                PlVehicle.tenant_no == tenant_no,
                PlVehicle.del_flag == 0,
            )
            .first()
        )
        return vehicle.license_plate if vehicle else owner_id

    personnel = (
        db.query(PlPersonnel)
        .filter(
            PlPersonnel.id == owner_id,
            PlPersonnel.tenant_no == tenant_no,
            PlPersonnel.del_flag == 0,
        )
        .first()
    )
    return personnel.personnel_name if personnel else owner_id


def _pending_reminder_for_cert(
    db: Session, cert_id: str
) -> Optional[PlDocumentReminder]:
    return (
        db.query(PlDocumentReminder)
        .filter(
            PlDocumentReminder.cert_id == cert_id,
            PlDocumentReminder.status == "pending",
            PlDocumentReminder.del_flag == 0,
        )
        .first()
    )


def _resolve_pending_reminder(
    reminder: PlDocumentReminder,
    *,
    remark: str,
    expire_date: Optional[date] = None,
    days_remaining: Optional[int] = None,
    document_type: Optional[str] = None,
    document_no: Optional[str] = None,
) -> None:
    """关闭待处理提醒：证件已处理/退出窗口后不再继续提醒。"""
    reminder.status = "resolved"
    reminder.remark = remark
    if expire_date is not None:
        reminder.expire_date = expire_date
    if days_remaining is not None:
        reminder.days_remaining = days_remaining
    if document_type is not None:
        reminder.document_type = document_type
    if document_no is not None:
        reminder.document_no = document_no


def scan_cert_expiry(db: Session, tenant_no: Optional[str] = None, *, today: Optional[date] = None) -> int:
    """扫描 pl_cert 生成到期提醒；退出提醒窗口或证件失效时关闭旧 pending。"""
    today = today or date.today()
    query = db.query(PlCert).filter(
        PlCert.del_flag == 0,
        PlCert.expire_date.isnot(None),
        PlCert.status == "valid",
    )
    if tenant_no:
        query = query.filter(PlCert.tenant_no == tenant_no)

    active_cert_ids: set[str] = set()
    created_count = 0
    for cert in query.all():
        active_cert_ids.add(cert.id)
        days_remaining = (cert.expire_date - today).days
        existing = _pending_reminder_for_cert(db, cert.id)

        # 尚未进入提醒窗口：关闭因旧有效期留下的 pending，等真正临近再提醒
        if days_remaining > cert.remind_days:
            if existing:
                _resolve_pending_reminder(
                    existing,
                    remark="系统自动关闭：证件有效期已更新，已退出提醒窗口",
                    expire_date=cert.expire_date,
                    days_remaining=days_remaining,
                    document_type=cert.cert_name,
                    document_no=cert.cert_no,
                )
            continue

        owner_label = _resolve_owner_label(
            db, cert.tenant_no, cert.owner_type, cert.owner_id
        )
        driver_id = cert.owner_id if cert.owner_type == "personnel" else None
        driver_name = owner_label if cert.owner_type == "personnel" else None

        if existing:
            existing.owner_type = cert.owner_type
            existing.owner_id = cert.owner_id
            existing.owner_label = owner_label
            existing.driver_id = driver_id
            existing.driver_name = driver_name
            existing.document_type = cert.cert_name
            existing.document_no = cert.cert_no
            existing.expire_date = cert.expire_date
            existing.days_remaining = days_remaining
            continue

        reminder = PlDocumentReminder(
            id=generate_uuid(),
            tenant_no=cert.tenant_no,
            cert_id=cert.id,
            owner_type=cert.owner_type,
            owner_id=cert.owner_id,
            owner_label=owner_label,
            driver_id=driver_id,
            driver_name=driver_name,
            document_type=cert.cert_name,
            document_no=cert.cert_no,
            expire_date=cert.expire_date,
            days_remaining=days_remaining,
            status="pending",
            create_by=cert.create_by or "system",
            create_dept_id=cert.create_dept_id or "",
        )
        db.add(reminder)
        created_count += 1

    # 软删/作废/无有效期的证件：关闭仍挂着的 pending
    stale_q = db.query(PlDocumentReminder).filter(
        PlDocumentReminder.status == "pending",
        PlDocumentReminder.del_flag == 0,
        PlDocumentReminder.cert_id.isnot(None),
    )
    if tenant_no:
        stale_q = stale_q.filter(PlDocumentReminder.tenant_no == tenant_no)
    for reminder in stale_q.all():
        if reminder.cert_id in active_cert_ids:
            continue
        _resolve_pending_reminder(
            reminder,
            remark="系统自动关闭：关联证件已删除或失效",
        )

    return created_count