package cn.iocoder.yudao.module.mes.service.dv.spare;

import cn.iocoder.yudao.framework.common.exception.ErrorCode;
import cn.iocoder.yudao.framework.common.pojo.PageResult;
import cn.iocoder.yudao.framework.common.util.object.BeanUtils;
import cn.iocoder.yudao.module.mes.controller.admin.dv.spare.vo.*;
import cn.iocoder.yudao.module.mes.dal.dataobject.dv.spare.*;
import cn.iocoder.yudao.module.mes.dal.dataobject.dv.repair.MesDvRepairDO;
import cn.iocoder.yudao.module.mes.dal.mysql.dv.spare.*;
import cn.iocoder.yudao.module.mes.dal.mysql.dv.repair.MesDvRepairMapper;
import cn.iocoder.yudao.module.mes.dal.mysql.dv.machinery.MesDvMachineryMapper;
import cn.iocoder.yudao.module.mes.enums.dv.MesDvRepairStatusEnum;
import cn.iocoder.yudao.module.system.api.user.AdminUserApi;
import jakarta.annotation.Resource;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.*;
import java.math.BigDecimal;
import java.util.*;
import static cn.iocoder.yudao.framework.common.exception.util.ServiceExceptionUtil.exception;

/** 备件库存只通过留痕的流水变更，元数据编辑不允许覆盖库存。 */
@Service
public class MesDvSpareService {
    private static final ErrorCode INVALID = new ErrorCode(1_040_807_001, "备件操作失败：{}");
    private static final BigDecimal MAX_QUANTITY = new BigDecimal("999999999999999.999");
    @Resource private MesDvSparePartMapper partMapper;
    @Resource private MesDvSpareMovementMapper movementMapper;
    @Resource private MesDvRepairMapper repairMapper;
    @Resource private MesDvMachineryMapper machineryMapper;
    @Resource private AdminUserApi adminUserApi;

    @Transactional(rollbackFor=Exception.class, isolation=Isolation.READ_COMMITTED)
    public Long create(MesDvSparePartSaveReqVO req, Long operator) {
        validateMetadata(req);
        MesDvSparePartDO part = BeanUtils.toBean(req,MesDvSparePartDO.class);
        part.setStockQuantity(req.getInitialQuantity());
        partMapper.insert(part);
        if (req.getInitialQuantity().signum()>0) {
            writeMovement(part,1,req.getInitialQuantity(),BigDecimal.ZERO,null,null,null,operator,
                    "opening-"+UUID.randomUUID(),"登记初始库存");
        }
        return part.getId();
    }
    @Transactional(rollbackFor=Exception.class, isolation=Isolation.READ_COMMITTED)
    public void update(MesDvSparePartSaveReqVO req) {
        MesDvSparePartDO part = requirePart(req.getId());
        validateMetadata(req);
        MesDvSparePartDO changes = BeanUtils.toBean(req,MesDvSparePartDO.class);
        changes.setStockQuantity(part.getStockQuantity());
        partMapper.updateById(changes);
    }
    private void validateMetadata(MesDvSparePartSaveReqVO req) {
        req.setCode(req.getCode().trim());
        req.setName(req.getName().trim());
        req.setUnit(req.getUnit().trim());
        if (req.getCode().isEmpty() || req.getName().isEmpty() || req.getUnit().isEmpty()) fail("编码、名称和单位不能为空");
        var old=partMapper.selectOne(MesDvSparePartDO::getCode,req.getCode());
        if(old!=null&&!Objects.equals(old.getId(),req.getId())) fail("备件编码已存在");
        if(req.getId()!=null && movementMapper.selectCount(MesDvSpareMovementDO::getSparePartId,req.getId())>0) {
            var saved=partMapper.selectById(req.getId());
            if(!Objects.equals(saved.getUnit(),req.getUnit())) fail("已有库存流水的备件不能修改计量单位");
        }
    }
    @Transactional(rollbackFor=Exception.class, isolation=Isolation.READ_COMMITTED)
    public void delete(Long id) {
        var part=requirePart(id);
        if(part.getStockQuantity().signum()!=0 || movementMapper.selectCount(MesDvSpareMovementDO::getSparePartId,id)>0)
            fail("有库存或已有流水的备件不能删除，请停用");
        partMapper.deleteById(id);
    }
    public MesDvSparePartDO get(Long id) { return partMapper.selectById(id); }
    public PageResult<MesDvSparePartDO> page(MesDvSparePageReqVO req) { return partMapper.page(req); }
    public PageResult<MesDvSpareMovementRespVO> movements(MesDvSparePageReqVO req) {
        var page=movementMapper.page(req);
        var ids=page.getList().stream().filter(m->m.getType()==3).map(MesDvSpareMovementDO::getId).toList();
        Map<Long,BigDecimal> totals=new HashMap<>();
        movementMapper.returns(ids).forEach(m->totals.merge(m.getOriginalId(),m.getQuantity(),BigDecimal::add));
        return new PageResult<>(page.getList().stream().map(m-> {
            var vo=BeanUtils.toBean(m,MesDvSpareMovementRespVO.class);
            vo.setReturnedQuantity(totals.getOrDefault(m.getId(),BigDecimal.ZERO));
            vo.setReturnableQuantity(m.getType()==3?m.getQuantity().subtract(vo.getReturnedQuantity()):BigDecimal.ZERO);
            return vo;
        }).toList(),page.getTotal());
    }
    @Transactional(rollbackFor=Exception.class, isolation=Isolation.READ_COMMITTED)
    public Long receive(MesDvSpareActionReqVO req,Long operator) {
        validateAction(req);
        var part=requirePart(req.getSparePartId());
        Long prior=duplicate(req,2,operator,part.getId(),null,null,null);
        if(prior!=null)return prior;
        requireEnabled(part);
        var before=part.getStockQuantity();
        changeStock(part,req.getQuantity());
        return writeMovement(part,2,req.getQuantity(),before,null,null,null,operator,req.getRequestKey(),req.getRemark());
    }
    @Transactional(rollbackFor=Exception.class, isolation=Isolation.READ_COMMITTED)
    public Long issue(MesDvSpareActionReqVO req,Long operator) {
        validateAction(req);
        if(req.getRepairId()==null || req.getSparePartId()==null || req.getReceiverUserId()==null) fail("请选择维修单、备件和领用人");
        // 与维修状态流转使用同一行锁；先维修单再备件，保持一致锁序。
        var repair=repairMapper.lockForSpare(req.getRepairId());
        if(repair==null)fail("维修单不存在");
        var part=requirePart(req.getSparePartId());
        Long prior=duplicate(req,3,operator,part.getId(),repair.getId(),null,req.getReceiverUserId());
        if(prior!=null)return prior;
        if(!Objects.equals(repair.getStatus(),MesDvRepairStatusEnum.PREPARE.getStatus()) &&
                !Objects.equals(repair.getStatus(),MesDvRepairStatusEnum.CONFIRMED.getStatus()))
            fail("仅草稿或维修中的维修单可以领用备件");
        requireEnabled(part);
        var receiver=adminUserApi.getUser(req.getReceiverUserId());
        if(receiver==null || !Objects.equals(receiver.getStatus(),0))fail("领用人不存在或已停用");
        var before=part.getStockQuantity();
        changeStock(part,req.getQuantity().negate());
        return writeMovement(part,3,req.getQuantity(),before,repair,null,req.getReceiverUserId(),
                operator,req.getRequestKey(),req.getRemark());
    }
    @Transactional(rollbackFor=Exception.class, isolation=Isolation.READ_COMMITTED)
    public Long returnPart(MesDvSpareActionReqVO req,Long operator) {
        validateAction(req);
        if(req.getOriginalId()==null)fail("请选择原领用记录");
        var original=movementMapper.lock(req.getOriginalId());
        if(original==null || original.getType()!=3)fail("原领用记录不存在");
        var part=requirePart(original.getSparePartId());
        Long prior=duplicate(req,4,operator,part.getId(),original.getRepairId(),original.getId(),original.getReceiverUserId());
        if(prior!=null)return prior;
        BigDecimal returned=movementMapper.returns(List.of(original.getId())).stream()
                .map(MesDvSpareMovementDO::getQuantity).reduce(BigDecimal.ZERO,BigDecimal::add);
        if(returned.add(req.getQuantity()).compareTo(original.getQuantity())>0)fail("退回数量超过尚未退回的领用数量");
        var before=part.getStockQuantity();
        changeStock(part,req.getQuantity()); // 已停用备件仍允许退回。
        var record=snapshot(part,4,req.getQuantity(),before,operator,req.getRequestKey(),req.getRemark());
        record.setOriginalId(original.getId());
        record.setRepairId(original.getRepairId()); record.setRepairCode(original.getRepairCode());
        record.setMachineryId(original.getMachineryId()); record.setMachineryName(original.getMachineryName());
        record.setReceiverUserId(original.getReceiverUserId()); record.setReceiverName(original.getReceiverName());
        movementMapper.insert(record);
        return record.getId();
    }
    private Long duplicate(MesDvSpareActionReqVO req,int type,Long operator,Long partId,Long repairId,Long originalId,Long receiverId) {
        var old=movementMapper.byKey(req.getRequestKey());
        if(old==null)return null;
        if(old.getType()!=type || !Objects.equals(old.getOperatorUserId(),operator)
                || !Objects.equals(old.getSparePartId(),partId) || !Objects.equals(old.getRepairId(),repairId)
                || !Objects.equals(old.getOriginalId(),originalId) || !Objects.equals(old.getReceiverUserId(),receiverId)
                || old.getQuantity().compareTo(req.getQuantity())!=0 || !Objects.equals(old.getRemark(),req.getRemark()))
            fail("请求标识已用于其他操作，请刷新后重试");
        return old.getId();
    }
    private void validateAction(MesDvSpareActionReqVO req) {
        if(req.getQuantity()==null || req.getQuantity().signum()<=0 || req.getQuantity().scale()>3
                || req.getQuantity().compareTo(MAX_QUANTITY)>0)fail("数量必须大于0，最多三位小数");
        if(req.getRemark()==null || req.getRemark().trim().isEmpty())fail("请填写操作说明");
    }
    private MesDvSparePartDO requirePart(Long id) {
        if(id==null)fail("请选择备件");
        var part=partMapper.lock(id);
        if(part==null)fail("备件不存在");
        return part;
    }
    private void requireEnabled(MesDvSparePartDO part) { if(!Objects.equals(part.getStatus(),0))fail("备件已停用"); }
    private void changeStock(MesDvSparePartDO part,BigDecimal delta) {
        var after=part.getStockQuantity().add(delta);
        if(after.signum()<0)fail("库存不足，当前可用："+part.getStockQuantity()+part.getUnit());
        if(after.compareTo(MAX_QUANTITY)>0)fail("库存数量超出系统允许范围");
        part.setStockQuantity(after);
        partMapper.updateById(new MesDvSparePartDO().setId(part.getId()).setStockQuantity(after));
    }
    private MesDvSpareMovementDO snapshot(MesDvSparePartDO part,int type,BigDecimal qty,BigDecimal before,
                                         Long operator,String key,String remark) {
        return new MesDvSpareMovementDO().setRequestKey(key).setSparePartId(part.getId())
                .setSparePartCode(part.getCode()).setSparePartName(part.getName()).setSpecification(part.getSpecification())
                .setUnit(part.getUnit()).setType(type).setQuantity(qty).setBeforeQuantity(before)
                .setAfterQuantity(part.getStockQuantity()).setOperatorUserId(operator).setRemark(remark);
    }
    private Long writeMovement(MesDvSparePartDO part,int type,BigDecimal qty,BigDecimal before,MesDvRepairDO repair,
                               Long original,Long receiver,Long operator,String key,String remark) {
        var record=snapshot(part,type,qty,before,operator,key,remark).setOriginalId(original).setReceiverUserId(receiver);
        if(receiver!=null)record.setReceiverName(adminUserApi.getUser(receiver).getNickname());
        if(repair!=null) {
            var machine=machineryMapper.selectById(repair.getMachineryId());
            if(machine==null)fail("维修设备不存在");
            record.setRepairId(repair.getId()).setRepairCode(repair.getCode()).setMachineryId(machine.getId()).setMachineryName(machine.getName());
        }
        movementMapper.insert(record);
        return record.getId();
    }
    private static void fail(String reason) { throw exception(INVALID,reason); }
}