package com.ruoyi.production.service.impl;

import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.core.toolkit.Wrappers;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.ruoyi.common.exception.ServiceException;
import com.ruoyi.common.exception.base.BaseException;
import com.ruoyi.common.utils.StringUtils;
import com.ruoyi.common.utils.bean.BeanUtils;
import com.ruoyi.common.utils.poi.ExcelUtil;
import com.ruoyi.production.bean.dto.ProductionPlanDto;
import com.ruoyi.production.bean.dto.ProductionPlanImportDto;
import com.ruoyi.production.bean.vo.ProductionPlanVo;
import com.ruoyi.production.mapper.ProductionOrderMapper;
import com.ruoyi.production.mapper.ProductionPlanMapper;
import com.ruoyi.production.pojo.ProductionOrder;
import com.ruoyi.production.pojo.ProductionPlan;
import com.ruoyi.production.service.ProductionOrderService;
import com.ruoyi.production.service.ProductionPlanService;
import jakarta.servlet.http.HttpServletResponse;
import lombok.RequiredArgsConstructor;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import org.springframework.web.multipart.MultipartFile;

import java.math.BigDecimal;
import java.time.LocalDateTime;
import java.util.*;
import java.util.stream.Collectors;

@Service
@RequiredArgsConstructor
public class ProductionPlanServiceImpl extends ServiceImpl<ProductionPlanMapper, ProductionPlan> implements ProductionPlanService {

    private static final int PLAN_STATUS_WAIT = 0;
    private static final int PLAN_STATUS_PARTIAL = 1;
    private static final int PLAN_STATUS_ISSUED = 2;

    private final ProductionPlanMapper productionPlanMapper;
    private final ProductionOrderMapper productionOrderMapper;
    private final ProductionOrderService productionOrderService;

    @Override
    public IPage<ProductionPlanVo> listPage(Page<ProductionPlanDto> page, ProductionPlanDto productionPlanDto) {
        return productionPlanMapper.listPage(page, productionPlanDto);
    }

    /**
     * 合并生产计划并下发生产订单。
     * 业务约束：
     * 1. 仅允许同一产品型号的计划合并；
     * 2. 已下发或部分下发的计划禁止再次合并；
     * 3. 下发数量不能大于所选计划需求总量；
     * 4. 订单创建统一复用 ProductionOrderService.saveProductionOrder，确保工艺/BOM/领料主单等后续逻辑一致。
     */
    @Override
    @Transactional(rollbackFor = Exception.class)
    public boolean combine(ProductionPlanDto productionPlanDto) {
        if (productionPlanDto == null || productionPlanDto.getIds() == null || productionPlanDto.getIds().isEmpty()) {
            return false;
        }

        List<Long> planIds = productionPlanDto.getIds().stream()
                .filter(Objects::nonNull)
                .distinct()
                .collect(Collectors.toList());
        if (planIds.isEmpty()) {
            throw new ServiceException("下发失败，未选择生产计划");
        }

        List<ProductionPlanDto> plans = productionPlanMapper.selectWithMaterialByIds(planIds);
        if (plans == null || plans.isEmpty() || plans.size() != planIds.size()) {
            throw new ServiceException("下发失败，生产计划不存在或已被删除");
        }

        ProductionPlanDto firstPlan = plans.getFirst();
        if (firstPlan.getProductModelId() == null) {
            throw new ServiceException("下发失败，生产计划缺少产品型号");
        }

        boolean hasDifferentModel = plans.stream()
                .anyMatch(item -> !Objects.equals(item.getProductModelId(), firstPlan.getProductModelId()));
        if (hasDifferentModel) {
            throw new BaseException("合并失败，所选生产计划的产品型号不一致");
        }

        boolean hasIssuedPlan = plans.stream()
                .anyMatch(item -> item.getStatus() != null && item.getStatus() != PLAN_STATUS_WAIT);
        if (hasIssuedPlan) {
            throw new BaseException("合并失败，所选生产计划存在已下发或部分下发数据");
        }

        BigDecimal totalRequiredQuantity = plans.stream()
                .map(ProductionPlan::getQtyRequired)
                .filter(Objects::nonNull)
                .reduce(BigDecimal.ZERO, BigDecimal::add);
        if (totalRequiredQuantity.compareTo(BigDecimal.ZERO) <= 0) {
            throw new ServiceException("下发失败，所选生产计划需求总量必须大于0");
        }

        BigDecimal assignedQuantity = productionPlanDto.getTotalAssignedQuantity();
        if (assignedQuantity == null || assignedQuantity.compareTo(BigDecimal.ZERO) <= 0) {
            throw new ServiceException("下发失败，下发数量必须大于0");
        }
        if (assignedQuantity.compareTo(totalRequiredQuantity) > 0) {
            throw new ServiceException("下发失败，下发数量不能大于计划需求总量");
        }

        ProductionOrder productionOrder = new ProductionOrder();
        productionOrder.setProductionPlanIds(formatPlanIds(planIds));
        productionOrder.setProductModelId(firstPlan.getProductModelId());
        productionOrder.setQuantity(assignedQuantity);
        productionOrder.setPlanCompleteTime(productionPlanDto.getPlanCompleteTime());

        boolean saved = productionOrderService.saveProductionOrder(productionOrder);
        if (!saved) {
            throw new ServiceException("下发失败，生产订单保存失败");
        }

        int targetStatus = assignedQuantity.compareTo(totalRequiredQuantity) < 0 ? PLAN_STATUS_PARTIAL : PLAN_STATUS_ISSUED;
        List<ProductionPlan> updates = planIds.stream().map(id -> {
            ProductionPlan update = new ProductionPlan();
            update.setId(id);
            update.setStatus(targetStatus);
            return update;
        }).collect(Collectors.toList());
        if (!updates.isEmpty()) {
            this.updateBatchById(updates);
        }
        return true;
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public boolean add(ProductionPlanDto dto) {
        if (StringUtils.isBlank(dto.getApplyNo())) {
            throw new ServiceException("新增失败，申请单编号不能为空");
        }
        checkApplyNoUnique(dto.getApplyNo(), null);

        dto.setStatus(PLAN_STATUS_WAIT);
        return productionPlanMapper.insert(dto) > 0;
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public boolean update(ProductionPlanDto dto) {
        if (dto == null || dto.getId() == null) {
            throw new ServiceException("编辑失败，数据不能为空");
        }

        ProductionPlan old = getById(dto.getId());
        if (old == null) {
            throw new ServiceException("编辑失败，生产计划不存在");
        }

        if (old.getStatus() != PLAN_STATUS_WAIT) {
            throw new BaseException("编辑失败，该生产计划已下发或部分下发，禁止编辑");
        }

        if (StringUtils.isNotBlank(dto.getApplyNo()) && !dto.getApplyNo().equals(old.getApplyNo())) {
            checkApplyNoUnique(dto.getApplyNo(), dto.getId());
        }

        return productionPlanMapper.updateById(dto) > 0;
    }

    private void checkApplyNoUnique(String applyNo, Long excludeId) {
        LambdaQueryWrapper<ProductionPlan> wrapper = Wrappers.lambdaQuery();
        wrapper.eq(ProductionPlan::getApplyNo, applyNo);
        if (excludeId != null) {
            wrapper.ne(ProductionPlan::getId, excludeId);
        }
        if (productionPlanMapper.selectCount(wrapper) > 0) {
            throw new ServiceException("申请单编号 " + applyNo + " 已存在");
        }
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public boolean delete(List<Long> ids) {
        if (productionPlanMapper.selectList(Wrappers.<ProductionPlan>lambdaQuery().in(ProductionPlan::getId, ids))
                .stream()
                .anyMatch(p -> p.getStatus() == PLAN_STATUS_PARTIAL || p.getStatus() == PLAN_STATUS_ISSUED)) {
            throw new BaseException("删除失败，存在已下发或部分下发的计划");
        }

        if (productionOrderMapper.selectList(Wrappers.<ProductionOrder>lambdaQuery().in(ProductionOrder::getProductionPlanIds, ids))
                .stream()
                .anyMatch(p -> p.getId() != null)) {
            throw new BaseException("删除失败，存在关联生产订单");
        }

        return productionPlanMapper.deleteBatchIds(ids) > 0;
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public void importProdData(MultipartFile file) {
        if (file == null || file.isEmpty()) {
            throw new ServiceException("导入数据不能为空");
        }

        ExcelUtil<ProductionPlanImportDto> excelUtil = new ExcelUtil<>(ProductionPlanImportDto.class);
        List<ProductionPlanImportDto> list;
        try {
            list = excelUtil.importExcel(file.getInputStream());
        } catch (Exception e) {
            throw new ServiceException("Excel解析失败");
        }

        if (list == null || list.isEmpty()) {
            throw new ServiceException("Excel没有数据");
        }

        Set<String> applyNos = new HashSet<>();
        Set<String> materialCodes = new HashSet<>();
        for (int i = 0; i < list.size(); i++) {
            ProductionPlanImportDto dto = list.get(i);
            String applyNo = dto.getApplyNo();
            String materialCode = dto.getMaterialCode();

            if (StringUtils.isEmpty(applyNo)) {
                throw new ServiceException("导入失败：第 " + (i + 2) + " 行申请单编号不能为空");
            }
            if (!applyNos.add(applyNo)) {
                throw new ServiceException("导入失败：Excel 中存在重复的申请单编号 " + applyNo);
            }
            if (StringUtils.isEmpty(materialCode)) {
                throw new ServiceException("导入失败：第 " + (i + 2) + " 行物料编码不能为空");
            }

            String strength = dto.getStrength();
            if (StringUtils.isNotEmpty(strength) && !"A3.5".equals(strength) && !"A5.0".equals(strength)) {
                throw new ServiceException("导入失败：第 " + (i + 2) + " 行强度只能是 A3.5 或 A5.0");
            }

            materialCodes.add(materialCode);
        }

        Long existApplyNoCount = baseMapper.selectCount(Wrappers.<ProductionPlan>lambdaQuery()
                .in(ProductionPlan::getApplyNo, applyNos));
        if (existApplyNoCount > 0) {
            List<String> existApplyNos = baseMapper.selectList(Wrappers.<ProductionPlan>lambdaQuery()
                            .in(ProductionPlan::getApplyNo, applyNos))
                    .stream()
                    .map(ProductionPlan::getApplyNo)
                    .collect(Collectors.toList());
            throw new ServiceException("导入失败，申请单编号已存在: " + String.join(", ", existApplyNos));
        }

        LocalDateTime now = LocalDateTime.now();
        List<ProductionPlan> entityList = list.stream().map(dto -> {
            ProductionPlan entity = new ProductionPlan();
            BeanUtils.copyProperties(dto, entity);
            entity.setStatus(PLAN_STATUS_WAIT);
            entity.setCreateTime(now);
            entity.setUpdateTime(now);
            return entity;
        }).collect(Collectors.toList());

        this.saveBatch(entityList);
    }

    @Override
    public void exportProdData(HttpServletResponse response, List<Long> ids) {
        List<ProductionPlan> list;
        if (ids != null && !ids.isEmpty()) {
            list = baseMapper.selectBatchIds(ids);
        } else {
            list = baseMapper.selectList(null);
        }

        List<ProductionPlanImportDto> exportList = new ArrayList<>();
        for (ProductionPlan entity : list) {
            ProductionPlanImportDto dto = new ProductionPlanImportDto();
            BeanUtils.copyProperties(entity, dto);
            exportList.add(dto);
        }
        ExcelUtil<ProductionPlanImportDto> util = new ExcelUtil<>(ProductionPlanImportDto.class);
        util.exportExcel(response, exportList, "销售生产需求数据");
    }

    private String formatPlanIds(List<Long> planIds) {
        return planIds.stream()
                .filter(Objects::nonNull)
                .distinct()
                .map(String::valueOf)
                .collect(Collectors.joining(",", "[", "]"));
    }
}