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.extension.plugins.pagination.Page;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.ruoyi.basic.pojo.Product;
import com.ruoyi.basic.pojo.ProductModel;
import com.ruoyi.basic.service.IProductModelService;
import com.ruoyi.basic.service.IProductService;
import com.ruoyi.common.exception.ServiceException;
import com.ruoyi.common.utils.StringUtils;
import com.ruoyi.common.utils.poi.ExcelUtil;
import com.ruoyi.framework.web.domain.AjaxResult;
import com.ruoyi.production.dto.BomImportDto;
import com.ruoyi.production.dto.ProductBomDto;
import com.ruoyi.production.dto.ProductStructureDto;
import com.ruoyi.production.mapper.ProductBomMapper;
import com.ruoyi.production.pojo.ProductBom;
import com.ruoyi.production.pojo.ProductProcess;
import com.ruoyi.production.pojo.ProductStructure;
import com.ruoyi.production.service.ProductBomService;
import com.ruoyi.production.service.ProductProcessService;
import com.ruoyi.production.service.ProductStructureService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.http.HttpServletResponse;
import java.math.BigDecimal;
import java.util.*;
import java.util.stream.Collectors;

/**
 * <p>
 * BOM主表 服务实现类
 * </p>
 *
 * @author 芯导软件（江苏）有限公司
 * @since 2026-01-15 09:59:27
 */
@Service
public class ProductBomServiceImpl extends ServiceImpl<ProductBomMapper, ProductBom> implements ProductBomService {

    @Autowired
    private IProductService productService;

    @Autowired
    private ProductBomMapper productBomMapper;


    @Autowired
    private IProductModelService productModelService;

    @Autowired
    private ProductStructureService productStructureService;

    @Autowired
    private ProductProcessService productProcessService;

    @Override
    public IPage<ProductBomDto> listPage(Page page, ProductBomDto productBomDto) {
        return productBomMapper.listPage(page, productBomDto);
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public AjaxResult add(ProductBom productBom) {
        boolean save = productBomMapper.insert(productBom) > 0;
        if (save) {
            String no = "BM." + String.format("%05d", productBom.getId());
            productBom.setBomNo(no);
            productBomMapper.updateById(productBom);

            //  查询出产品模型信息
            if (productBom.getProductModelId() == null) {
                throw new ServiceException("请选择产品模型");
            }

            ProductModel productModel = productModelService.getById(productBom.getProductModelId());
            if (productModel == null) {
                throw new ServiceException("选择的产品模型不存在");
            }

            //  添加初始的产品结构
            ProductStructure productStructure = new ProductStructure();
            productStructure.setProductModelId(productBom.getProductModelId());
            productStructure.setUnit(productModel.getUnit());
            productStructure.setUnitQuantity(BigDecimal.valueOf(1));
            productStructure.setBomId(productBom.getId());

            productStructureService.save(productStructure);

            return AjaxResult.success();
        }
        return AjaxResult.error();
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public AjaxResult uploadBom(MultipartFile file) {
        ExcelUtil<BomImportDto> util = new ExcelUtil<>(BomImportDto.class);
        List<BomImportDto> list;
        try {
            list = util.importExcel(file.getInputStream());
        } catch (Exception e) {
            return AjaxResult.error("Excel解析失败");
        }

        if (list == null || list.isEmpty()) return AjaxResult.error("数据为空");

        //  处理工序
        list.forEach(dto -> {
            dto.setParentName(clean(dto.getParentName()));
            dto.setParentSpec(clean(dto.getParentSpec()));
            dto.setChildName(clean(dto.getChildName()));
            dto.setChildSpec(clean(dto.getChildSpec()));
        });
        handleProcess(list);
        Map<String, Long> processMap = productProcessService.list().stream()
                .collect(Collectors.toMap(ProductProcess::getName, ProductProcess::getId, (k1, k2) -> k1));

        //  创建 BOM 数据
        BomImportDto first = list.get(0);
        ProductModel rootModel = findModel(first.getParentName(), first.getParentSpec());
        ProductBom bom = new ProductBom();
        bom.setProductModelId(rootModel.getId());
        bom.setVersion("1.0");
        productBomMapper.insert(bom);
        bom.setBomNo("BM." + String.format("%05d", bom.getId()));
        productBomMapper.updateById(bom);

        // 记录已经插入结构的节点：Key = "名称+规格", Value = structure_id
        Map<String, Long> treePathMap = new HashMap<>();

        for (int i = 0; i < list.size(); i++) {
            BomImportDto dto = list.get(i);
            String parentKey = dto.getParentName() + "|" + dto.getParentSpec();
            String childKey = dto.getChildName() + "|" + dto.getChildSpec();

            //处理根节点,第一行且子项为空
            if (i == 0 && StringUtils.isBlank(dto.getChildName())) {
                ProductStructure rootNode = new ProductStructure();
                rootNode.setBomId(bom.getId());
                rootNode.setParentId(null); // 顶层没有父节点
                rootNode.setProductModelId(rootModel.getId());
                rootNode.setUnitQuantity(BigDecimal.ONE);
                rootNode.setUnit(rootModel.getUnit());
                productStructureService.save(rootNode);

                treePathMap.put(parentKey, rootNode.getId());
                continue;
            }

            //  处理子层级节点
            //  找到父节点在数据库里的 ID
            Long parentStructureId = treePathMap.get(parentKey);
            if (parentStructureId == null) {
                // 如果 Map 里找不到，说明 Excel 顺序乱了或者数据有误
                throw new ServiceException("导入失败: 父项[" + dto.getParentName() + "]必须在其子项之前定义");
            }

            //  获取子项模型信息
            ProductModel childModel = findModel(dto.getChildName(), dto.getChildSpec());

            //  插入结构表
            ProductStructure node = new ProductStructure();
            node.setBomId(bom.getId());
            node.setParentId(parentStructureId); // 父节点ID
            node.setProductModelId(childModel.getId());
            node.setUnitQuantity(dto.getUnitQty());
            node.setUnit(childModel.getUnit());
            if (processMap.containsKey(dto.getProcess())) {
                node.setProcessId(processMap.get(dto.getProcess()));
            }
            productStructureService.save(node);

            //  把当前子项记录到 Map,作为以后更深层级的父项查找依据
            //  同一父项下的同名子项不需要重复记录
            treePathMap.put(childKey, node.getId());
        }

        return AjaxResult.success("BOM导入成功");
    }


    @Override
    public void exportBom(HttpServletResponse response, Integer bomId) {
        if (bomId == null) {
            return;
        }

        List<ProductStructureDto> treeData = productStructureService.listBybomId(bomId);
        if (treeData == null || treeData.isEmpty()) {
            return;
        }

        //  将树形结构扁平化 使用 BFS算法 导出,按层级顺序
        List<BomImportDto> exportList = new ArrayList<>();

        // Map<ID, Node> idMap 用于查找父节点
        Map<Long, ProductStructureDto> idMap = new HashMap<>();
        populateMap(treeData, idMap);

        //  treeData 的第一个是根节点
        for (ProductStructureDto root : treeData) {
            //  添加根节点
            BomImportDto rootRow = new BomImportDto();
            rootRow.setParentName(root.getProductName());
            rootRow.setParentSpec(root.getModel());
            rootRow.setUnitQty(root.getUnitQuantity());
            rootRow.setRemark("");
            exportList.add(rootRow);

            //  BFS 遍历-队列
            Queue<ProductStructureDto> queue = new LinkedList<>();
            if (root.getChildren() != null) {
                queue.addAll(root.getChildren());
            }

            while (!queue.isEmpty()) {
                ProductStructureDto child = queue.poll();

                // 查找父节点
                ProductStructureDto parent = idMap.get(child.getParentId());
                if (parent == null) {
                    // 除了最外层节点,其他节点的父类肯定是不会为空的
                    continue;
                }

                BomImportDto row = new BomImportDto();
                // 父类信息
                row.setParentName(parent.getProductName());
                row.setParentSpec(parent.getModel());
                // 子类信息
                row.setChildName(child.getProductName());
                row.setChildSpec(child.getModel());
                row.setUnitQty(child.getUnitQuantity());
                row.setProcess(child.getProcessName());

                exportList.add(row);

                //  将子节点的子节点加入队列-下一层
                if (child.getChildren() != null && !child.getChildren().isEmpty()) {
                    queue.addAll(child.getChildren());
                }
            }
        }

        ExcelUtil<BomImportDto> util = new ExcelUtil<>(BomImportDto.class);
        util.exportExcel(response, exportList, "BOM结构导出");
    }

    private void populateMap(List<ProductStructureDto> nodes, Map<Long, ProductStructureDto> map) {
        if (nodes == null || nodes.isEmpty()) {
            return;
        }
        for (ProductStructureDto node : nodes) {
            map.put(node.getId(), node);
            populateMap(node.getChildren(), map);
        }
    }

    private ProductModel findModel(String name, String spec) {
        Product product = productService.getOne(new LambdaQueryWrapper<Product>()
                .eq(Product::getProductName, name).last("limit 1"));
        if (product == null) throw new ServiceException("产品未维护：" + name);

        ProductModel model = productModelService.getOne(new LambdaQueryWrapper<ProductModel>()
                .eq(ProductModel::getProductId, product.getId())
                .eq(ProductModel::getModel, spec).last("limit 1"));
        if (model == null) throw new ServiceException("规格未维护：" + name + "[" + spec + "]");
        return model;
    }

    private void handleProcess(List<BomImportDto> list) {

        Set<String> processNames = list.stream()
                .map(BomImportDto::getProcess)
                .filter(StringUtils::isNotBlank)
                .collect(Collectors.toSet());

        if (processNames.isEmpty()) {
            return;
        }

        List<ProductProcess> exists = productProcessService.list(
                new LambdaQueryWrapper<ProductProcess>().in(ProductProcess::getName, processNames)
        );

        Set<String> existNames = exists.stream()
                .map(ProductProcess::getName)
                .collect(Collectors.toSet());

        List<ProductProcess> needSave = processNames.stream()
                .filter(n -> !existNames.contains(n))
                .map(n -> {
                    ProductProcess p = new ProductProcess();
                    p.setName(n);
                    return p;
                })
                .collect(Collectors.toList());

        if (!needSave.isEmpty()) {
            productProcessService.saveBatch(needSave);
            needSave.forEach(p -> p.setNo("GX" + String.format("%08d", p.getId())));
            productProcessService.updateBatchById(needSave);
        }
    }

    private String clean(String s) {
        if (s == null) return null;
        return s.replaceAll("[\\u00A0\\u3000]", "").trim();
    }
}