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.production.pojo.ProductMaterial;
import com.ruoyi.production.pojo.ProductMaterialSku;
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.*;
import com.ruoyi.project.system.domain.SysDictData;
import com.ruoyi.project.system.mapper.SysDictDataMapper;
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 ProductBomMapper productBomMapper;

    @Autowired
    private ProductStructureService productStructureService;

    @Autowired
    private ProductProcessService productProcessService;

    @Autowired
    private ProductMaterialService productMaterialService;

    @Autowired
    private ProductMaterialSkuService productMaterialSkuService;

    @Autowired
    private SysDictDataMapper sysDictDataMapper;

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

    @Override
    @Transactional(rollbackFor = Exception.class)
    public AjaxResult add(ProductBom productBom) {
        if (productBom == null || productBom.getDictCode() == null) {
            throw new ServiceException("新增BOM失败,产品类型不能为空");
        }

        SysDictData sysDictData = sysDictDataMapper.selectDictDataById(productBom.getDictCode());
        if (sysDictData == null) {
            throw new ServiceException("新增BOM失败,产品类型不存在");
        }

        boolean save = productBomMapper.insert(productBom) > 0;
        if (save) {
            String no = "BM." + String.format("%05d", productBom.getId());
            productBom.setBomNo(no);
            productBomMapper.updateById(productBom);

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

    @Override
    @Transactional(rollbackFor = Exception.class)
    public AjaxResult uploadBom(MultipartFile file, Long dictCode) {
        if (dictCode == null) {
            return AjaxResult.error("导入失败,产品类型不能为空");
        }
        SysDictData sysDictData = sysDictDataMapper.selectDictDataById(dictCode);
        if (sysDictData == null) {
            return AjaxResult.error("导入失败,产品类型不存在");
        }
        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");
        }

        list.forEach(dto -> {
            dto.setParentName(clean(dto.getParentName()));
            dto.setParentSpec(clean(dto.getParentSpec()));
            dto.setChildName(clean(dto.getChildName()));
            dto.setChildSpec(clean(dto.getChildSpec()));
            dto.setProcess(clean(dto.getProcess()));
        });

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

        Map<String, Long> processMap = new HashMap<>();
        if (!processNames.isEmpty()) {
            List<ProductProcess> exists = productProcessService.list(
                    new LambdaQueryWrapper<ProductProcess>().in(ProductProcess::getName, processNames)
            );
            processMap = exists.stream().collect(Collectors.toMap(ProductProcess::getName, ProductProcess::getId, (k1, k2) -> k1));

            Map<String, Long> finalProcessMap = processMap;
            List<String> missingProcesses = processNames.stream()
                    .filter(n -> !finalProcessMap.containsKey(n))
                    .collect(Collectors.toList());

            if (!missingProcesses.isEmpty()) {
                throw new ServiceException("导入失败，以下工序不存在：" + String.join(", ", missingProcesses));
            }
        }

        Set<String> materialKeys = new HashSet<>();
        for (BomImportDto dto : list) {
            if (StringUtils.isNotBlank(dto.getParentName())) {
                materialKeys.add(dto.getParentName() + "|" + (dto.getParentSpec() == null ? "" : dto.getParentSpec()));
            }
            if (StringUtils.isNotBlank(dto.getChildName())) {
                materialKeys.add(dto.getChildName() + "|" + (dto.getChildSpec() == null ? "" : dto.getChildSpec()));
            }
        }

        Map<String, ProductMaterialSku> skuMap = validateAndGetSkuMap(materialKeys);

        ProductBom bom = new ProductBom();
        bom.setDictCode(dictCode);
        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 (BomImportDto dto : list) {
            String parentName = dto.getParentName();
            String parentSpec = dto.getParentSpec();
            String childName = dto.getChildName();
            String childSpec = dto.getChildSpec();

            String parentKey = parentName + "|" + (parentSpec == null ? "" : parentSpec);
            String childKey = childName + "|" + (childSpec == null ? "" : childSpec);

            //  处理顶级节点 (子项及其规格均为空当作顶级节点定义)
            if (StringUtils.isBlank(childName) && StringUtils.isBlank(childSpec)) {
                if (!treePathMap.containsKey(parentKey)) {
                    ProductMaterialSku model = skuMap.get(parentKey);
                    ProductStructure node = saveStructure(bom.getId(), null, model, dto.getUnitQty(), null);
                    treePathMap.put(parentKey, node.getId());
                } else {
                    // 如果已经存在，仅在它是顶级节点时更新
                    Long structureId = treePathMap.get(parentKey);
                    ProductStructure node = productStructureService.getById(structureId);
                    if (node != null && node.getParentId() == null && dto.getUnitQty() != null) {
                        node.setUnitQuantity(dto.getUnitQty());
                        productStructureService.updateById(node);
                    }
                }
                continue;
            }

            //  处理父子层级关系
            Long parentStructureId = treePathMap.get(parentKey);
            if (parentStructureId == null) {
                // 如果 Map 里找不到父节点，视为顶级父节点
                ProductMaterialSku parentModel = skuMap.get(parentKey);
                ProductStructure parentNode = saveStructure(bom.getId(), null, parentModel, BigDecimal.ONE, null);
                parentStructureId = parentNode.getId();
                treePathMap.put(parentKey, parentStructureId);
            }

            //  获取子项模型信息
            ProductMaterialSku childModel = skuMap.get(childKey);
            Long processId = null;
            if (StringUtils.isNotBlank(dto.getProcess())) {
                processId = processMap.get(dto.getProcess());
            }
            // 插入子节点结构表
            ProductStructure childNode = saveStructure(bom.getId(), parentStructureId, childModel, dto.getUnitQty(), processId);
            // 把当前子项记录到 Map,作为以后更深层级的父项查找依据
            treePathMap.put(childKey, childNode.getId());
        }

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

    /**
     * 保存结构节点
     */
    private ProductStructure saveStructure(Integer bomId, Long parentId, ProductMaterialSku model, BigDecimal qty, Long processId) {
        ProductStructure node = new ProductStructure();
        node.setBomId(bomId);
        node.setParentId(parentId);
        node.setProductModelId(model.getId());
        node.setUnitQuantity(qty != null ? qty : BigDecimal.ONE);
        ProductMaterial material = productMaterialService.getById(model.getProductId());
        node.setUnit(material != null ? material.getUnit() : null);
        node.setProcessId(processId);
        productStructureService.save(node);
        return node;
    }


    @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");
    }

    @Override
    public String strengthById(Long bomId) {
        if (bomId == null) {
            return null;
        }
        return baseMapper.selectStrengthById(bomId);
    }

    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);
        }
    }


    /**
     * 批量验证并获取产品SKU信息
     */
    private Map<String, ProductMaterialSku> validateAndGetSkuMap(Set<String> materialKeys) {
        if (materialKeys == null || materialKeys.isEmpty()) {
            return Collections.emptyMap();
        }

        // 1. 获取所有产品名称并查询
        Set<String> productNames = materialKeys.stream()
                .map(k -> k.split("\\|")[0])
                .collect(Collectors.toSet());

        List<ProductMaterial> products = productMaterialService.list(
                new LambdaQueryWrapper<ProductMaterial>().in(ProductMaterial::getProductName, productNames)
        );
        Map<String, ProductMaterial> productMap = products.stream()
                .collect(Collectors.toMap(ProductMaterial::getProductName, p -> p, (k1, k2) -> k1));

        // 检查缺失的产品
        List<String> missingProducts = productNames.stream()
                .filter(n -> !productMap.containsKey(n))
                .collect(Collectors.toList());
        if (!missingProducts.isEmpty()) {
            throw new ServiceException("导入失败，以下产品未维护：" + String.join(", ", missingProducts));
        }

        // 2. 查询所有相关的 SKU
        // 构造查询：(productId = ? AND model = ?) OR (productId = ? AND model = ?) ...
        // 由于 MyBatis Plus 的 Or 嵌套可能较慢且此处数量通常可控，我们可以先查出所有这些 Product 的所有 SKU
        List<Long> productIds = products.stream().map(ProductMaterial::getId).collect(Collectors.toList());
        List<ProductMaterialSku> skus = productMaterialSkuService.list(
                new LambdaQueryWrapper<ProductMaterialSku>().in(ProductMaterialSku::getProductId, productIds)
        );

        // 构建 Map: "产品名称|规格" -> Sku
        Map<String, ProductMaterialSku> skuMap = new HashMap<>();
        for (ProductMaterialSku sku : skus) {
            ProductMaterial p = productMap.values().stream()
                    .filter(pm -> pm.getId().equals(sku.getProductId()))
                    .findFirst().orElse(null);
            if (p != null) {
                String key = p.getProductName() + "|" + (sku.getModel() == null ? "" : sku.getModel());
                skuMap.put(key, sku);
            }
        }

        // 检查缺失的规格
        List<String> missingSkus = materialKeys.stream()
                .filter(k -> !skuMap.containsKey(k))
                .map(k -> {
                    String[] parts = k.split("\\|");
                    return parts[0] + "[" + (parts.length > 1 ? parts[1] : "") + "]";
                })
                .collect(Collectors.toList());

        if (!missingSkus.isEmpty()) {
            throw new ServiceException("导入失败，以下产品规格未维护：" + String.join(", ", missingSkus));
        }

        return skuMap;
    }

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