"""缺料审批接口

核心原则：
- 所有写操作仅在 pms_db（PmsMaterialApproval 表）中进行
- 绝对禁止对 inventory_db 进行任何写操作
- 物料信息（MaterialBase）仅从只读库查询，不进行写操作
"""
from fastapi import APIRouter, Depends, HTTPException, Query
from sqlalchemy.orm import Session

from app.database import get_db_pms
from app.models import PmsWorkOrder, PmsMaterialApproval, MaterialBase, ApprovalStatus
from app.schemas.approval import (
    ApprovalCreate,
    ApprovalStatusUpdate,
    ApprovalDetailResponse,
)

router = APIRouter(prefix="/api/approvals", tags=["缺料审批"])


@router.post(
    "",
    response_model=ApprovalDetailResponse,
    status_code=201,
    summary="员工提交缺料审批申请",
)
async def create_approval(data: ApprovalCreate, db: Session = Depends(get_db_pms)):
    work_order = db.query(PmsWorkOrder).filter(
        PmsWorkOrder.id == data.work_order_id
    ).first()
    if not work_order:
        raise HTTPException(status_code=400, detail=f"工单 ID={data.work_order_id} 不存在")

    material = db.query(MaterialBase).filter(
        MaterialBase.id == data.missing_material_id
    ).first()
    if not material:
        raise HTTPException(status_code=400, detail=f"物料 ID={data.missing_material_id} 不存在")

    approval = PmsMaterialApproval(
        work_order_id=data.work_order_id,
        missing_material_id=data.missing_material_id,
        required_qty=data.required_qty,
        reason=data.reason,
        status=ApprovalStatus.PENDING,
    )
    db.add(approval)
    db.commit()
    db.refresh(approval)

    return ApprovalDetailResponse(
        id=approval.id,
        work_order_id=approval.work_order_id,
        work_order_no=work_order.work_order_no,
        missing_material_id=approval.missing_material_id,
        material_name=material.name,
        required_qty=approval.required_qty,
        reason=approval.reason,
        status=approval.status,
        created_at=approval.created_at,
    )


@router.get(
    "",
    response_model=list[ApprovalDetailResponse],
    summary="查询待审批列表",
)
async def list_pending_approvals(
    skip: int = Query(0, ge=0),
    limit: int = Query(20, gt=0, le=100),
    db: Session = Depends(get_db_pms)
):
    approvals = db.query(PmsMaterialApproval).filter(
        PmsMaterialApproval.status == ApprovalStatus.PENDING
    ).order_by(
        PmsMaterialApproval.created_at.desc()
    ).offset(skip).limit(limit).all()

    if not approvals:
        return []

    work_order_ids = list(set(a.work_order_id for a in approvals))
    material_ids = list(set(a.missing_material_id for a in approvals))

    work_orders = {
        wo.id: wo for wo in db.query(PmsWorkOrder).filter(
            PmsWorkOrder.id.in_(work_order_ids)
        ).all()
    }
    materials = {
        m.id: m for m in db.query(MaterialBase).filter(
            MaterialBase.id.in_(material_ids)
        ).all()
    }

    result = []
    for approval in approvals:
        wo = work_orders.get(approval.work_order_id)
        mat = materials.get(approval.missing_material_id)
        result.append(ApprovalDetailResponse(
            id=approval.id,
            work_order_id=approval.work_order_id,
            work_order_no=wo.work_order_no if wo else f"WO-{approval.work_order_id}",
            missing_material_id=approval.missing_material_id,
            material_name=mat.name if mat else f"物料-{approval.missing_material_id}",
            required_qty=approval.required_qty,
            reason=approval.reason,
            status=approval.status,
            created_at=approval.created_at,
        ))

    return result


@router.put(
    "/{approval_id}/status",
    response_model=ApprovalDetailResponse,
    summary="主管审批",
)
async def update_approval_status(
    approval_id: int,
    data: ApprovalStatusUpdate,
    db: Session = Depends(get_db_pms)
):
    approval = db.query(PmsMaterialApproval).filter(
        PmsMaterialApproval.id == approval_id
    ).first()
    if not approval:
        raise HTTPException(status_code=404, detail=f"审批记录 ID={approval_id} 不存在")

    if approval.status != ApprovalStatus.PENDING:
        raise HTTPException(status_code=400, detail=f"当前状态为 {approval.status.value}，终态不可再次修改")

    if data.status == ApprovalStatus.PENDING:
        raise HTTPException(status_code=400, detail="不允许将状态改回 PENDING")

    approval.status = data.status
    db.commit()
    db.refresh(approval)

    work_order = db.query(PmsWorkOrder).filter(
        PmsWorkOrder.id == approval.work_order_id
    ).first()
    material = db.query(MaterialBase).filter(
        MaterialBase.id == approval.missing_material_id
    ).first()

    return ApprovalDetailResponse(
        id=approval.id,
        work_order_id=approval.work_order_id,
        work_order_no=work_order.work_order_no if work_order else f"WO-{approval.work_order_id}",
        missing_material_id=approval.missing_material_id,
        material_name=material.name if material else f"物料-{approval.missing_material_id}",
        required_qty=approval.required_qty,
        reason=approval.reason,
        status=approval.status,
        created_at=approval.created_at,
    )


@router.get(
    "/{approval_id}",
    response_model=ApprovalDetailResponse,
    summary="获取审批详情",
)
async def get_approval(
    approval_id: int,
    db: Session = Depends(get_db_pms)
):
    approval = db.query(PmsMaterialApproval).filter(
        PmsMaterialApproval.id == approval_id
    ).first()
    if not approval:
        raise HTTPException(status_code=404, detail=f"审批记录 ID={approval_id} 不存在")

    work_order = db.query(PmsWorkOrder).filter(
        PmsWorkOrder.id == approval.work_order_id
    ).first()
    material = db.query(MaterialBase).filter(
        MaterialBase.id == approval.missing_material_id
    ).first()

    return ApprovalDetailResponse(
        id=approval.id,
        work_order_id=approval.work_order_id,
        work_order_no=work_order.work_order_no if work_order else f"WO-{approval.work_order_id}",
        missing_material_id=approval.missing_material_id,
        material_name=material.name if material else f"物料-{approval.missing_material_id}",
        required_qty=approval.required_qty,
        reason=approval.reason,
        status=approval.status,
        created_at=approval.created_at,
    )