package com.ruoyi.sales.service.impl;

import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.baomidou.mybatisplus.core.toolkit.CollectionUtils;
import com.baomidou.mybatisplus.core.toolkit.Wrappers;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.ruoyi.basic.mapper.CustomerMapper;
import com.ruoyi.basic.pojo.Customer;
import com.ruoyi.common.exception.base.BaseException;
import com.ruoyi.common.utils.StringUtils;
import com.ruoyi.other.mapper.TempFileMapper;
import com.ruoyi.other.pojo.TempFile;
import com.ruoyi.sales.dto.MonthlyAmountDto;
import com.ruoyi.sales.dto.SalesLedgerDto;
import com.ruoyi.sales.mapper.*;
import com.ruoyi.sales.pojo.*;
import com.ruoyi.sales.service.ISalesLedgerService;
import lombok.RequiredArgsConstructor;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.io.FilenameUtils;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.core.script.DefaultRedisScript;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import java.io.IOException;
import java.lang.reflect.Field;
import java.math.BigDecimal;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.nio.file.StandardCopyOption;
import java.time.LocalDate;
import java.time.LocalDateTime;
import java.time.YearMonth;
import java.time.format.DateTimeFormatter;
import java.util.*;
import java.util.concurrent.TimeUnit;
import java.util.function.Function;
import java.util.stream.Collectors;

/**
 * 销售台账Service业务层处理
 *
 * @author ruoyi
 * @date 2025-05-08
 */
@Service
@RequiredArgsConstructor
@Slf4j
public class SalesLedgerServiceImpl extends ServiceImpl<SalesLedgerMapper, SalesLedger> implements ISalesLedgerService {

    private final SalesLedgerMapper salesLedgerMapper;

    private final CustomerMapper customerMapper;

    private final SalesLedgerProductMapper salesLedgerProductMapper;

    private final CommonFileMapper commonFileMapper;

    private final TempFileMapper tempFileMapper;

    private final ReceiptPaymentMapper receiptPaymentMapper;

    private final InvoiceLedgerMapper invoiceLedgerMapper;

    @Autowired
    private InvoiceRegistrationProductMapper invoiceRegistrationProductMapper;

    @Value("${file.upload-dir}")
    private String uploadDir;

    private static final String LOCK_PREFIX = "contract_no_lock:";
    private static final long LOCK_WAIT_TIMEOUT = 10; // 锁等待超时时间（秒）
    private static final long LOCK_EXPIRE_TIME = 30;  // 锁自动过期时间（秒）

    private final RedisTemplate<String, String> redisTemplate;

    @Override
    public List<SalesLedger> selectSalesLedgerList(SalesLedgerDto salesLedgerDto) {
        LambdaQueryWrapper<SalesLedger> queryWrapper = new LambdaQueryWrapper<>();
        if (StringUtils.isNotBlank(salesLedgerDto.getCustomerName())) {
            queryWrapper.eq(SalesLedger::getCustomerName, salesLedgerDto.getCustomerName());
        }
        return salesLedgerMapper.selectList(queryWrapper);
    }

    public SalesLedgerDto getSalesLedgerWithProducts(SalesLedgerDto salesLedgerDto) {
        // 1. 查询主表
        SalesLedger salesLedger = salesLedgerMapper.selectById(salesLedgerDto.getId());
        if (salesLedger == null) {
            throw new BaseException("台账不存在");
        }

        // 2. 查询子表
        LambdaQueryWrapper<SalesLedgerProduct> productWrapper = new LambdaQueryWrapper<>();
        productWrapper.eq(SalesLedgerProduct::getSalesLedgerId, salesLedger.getId());
        List<SalesLedgerProduct> products = salesLedgerProductMapper.selectList(productWrapper);
        for (SalesLedgerProduct product : products) {
            product.setOriginalNoInvoiceNum(product.getNoInvoiceNum());
        }

        // 3.查询上传文件
        LambdaQueryWrapper<CommonFile> salesLedgerFileWrapper = new LambdaQueryWrapper<>();
        salesLedgerFileWrapper.eq(CommonFile::getCommonId, salesLedger.getId());
        List<CommonFile> salesLedgerFiles = commonFileMapper.selectList(salesLedgerFileWrapper);

        // 4. 转换 DTO
        SalesLedgerDto resultDto = new SalesLedgerDto();
        BeanUtils.copyProperties(salesLedger, resultDto);
        if (!products.isEmpty()) {
            resultDto.setHasChildren(true);
            resultDto.setProductData(products);
            resultDto.setSalesLedgerFiles(salesLedgerFiles);
        }
        return resultDto;
    }

    @Override
    public List<Map<String, Object>> getSalesNo() {
        LambdaQueryWrapper<SalesLedger> queryWrapper = Wrappers.lambdaQuery();
        queryWrapper.select(SalesLedger::getId, SalesLedger::getSalesContractNo);

        // 获取原始查询结果
        List<Map<String, Object>> result = salesLedgerMapper.selectMaps(queryWrapper);

        // 将下划线命名转换为驼峰命名
        return result.stream().map(map -> map.entrySet().stream()
                .collect(Collectors.toMap(
                        entry -> underlineToCamel(entry.getKey()),
                        Map.Entry::getValue))
        ).collect(Collectors.toList());
    }

    @Override
    public BigDecimal getContractAmount() {
        LocalDate now = LocalDate.now();
        YearMonth currentMonth = YearMonth.from(now);

        // 创建LambdaQueryWrapper
        LambdaQueryWrapper<SalesLedger> queryWrapper = new LambdaQueryWrapper<>();
        queryWrapper.ge(SalesLedger::getEntryDate, currentMonth.atDay(1).atStartOfDay())  // 大于等于本月第一天
                .lt(SalesLedger::getEntryDate, currentMonth.plusMonths(1).atDay(1).atStartOfDay()); // 小于下月第一天

        // 执行查询并计算总和
        List<SalesLedger> salesLedgers = salesLedgerMapper.selectList(queryWrapper);

        BigDecimal totalContractAmount = salesLedgers.stream()
                .map(SalesLedger::getContractAmount)
                .filter(Objects::nonNull)
                .reduce(BigDecimal.ZERO, BigDecimal::add);

        return totalContractAmount;
    }

    @Override
    public List getTopFiveList() {
        // 查询原始数据
        LambdaQueryWrapper<SalesLedger> queryWrapper = Wrappers.lambdaQuery();
        queryWrapper.select(SalesLedger::getCustomerId,
                        SalesLedger::getCustomerName,
                        SalesLedger::getContractAmount)
                .orderByDesc(SalesLedger::getContractAmount);
        List<SalesLedger> records = salesLedgerMapper.selectList(queryWrapper);

        // 按客户ID分组并聚合金额
        Map<Long, GroupedCustomer> groupedMap = new LinkedHashMap<>(); // 使用LinkedHashMap保持排序
        for (SalesLedger record : records) {
            groupedMap.computeIfAbsent(record.getCustomerId(),
                            k -> new GroupedCustomer(record.getCustomerId(), record.getCustomerName()))
                    .addAmount(record.getContractAmount());
        }

        // 转换为结果列表并取前5
        return groupedMap.values().stream()
                .sorted(Comparator.comparing(GroupedCustomer::getTotalAmount).reversed())
                .limit(5)
                .map(customer -> {
                    Map<String, Object> result = new HashMap<>();
                    result.put("customerId", customer.getCustomerId());
                    result.put("customerName", customer.getCustomerName());
                    result.put("totalAmount", customer.getTotalAmount());
                    return result;
                })
                .collect(Collectors.toList());
    }

    @Override
    public List<MonthlyAmountDto> getAmountHalfYear() {
        LocalDate now = LocalDate.now();
        YearMonth currentMonth = YearMonth.from(now);

        List<MonthlyAmountDto> monthlyAmounts = new ArrayList<>();

        for (int i = 0; i < 6; i++) {
            YearMonth targetMonth = currentMonth.minusMonths(i);
            LocalDate firstDayOfMonth = targetMonth.atDay(1);
            LocalDate firstDayOfNextMonth = targetMonth.plusMonths(1).atDay(1);

            LocalDateTime startOfMonth = firstDayOfMonth.atStartOfDay();
            LocalDateTime startOfNextMonth = firstDayOfNextMonth.atStartOfDay();

            LambdaQueryWrapper<ReceiptPayment> receiptPaymentLambdaQueryWrapper = new LambdaQueryWrapper<>();
            receiptPaymentLambdaQueryWrapper.ge(ReceiptPayment::getCreateTime, startOfMonth)
                    .lt(ReceiptPayment::getCreateTime, startOfNextMonth);

            LambdaQueryWrapper<InvoiceLedger> invoiceLedgerLambdaQueryWrapper = new LambdaQueryWrapper<>();
            invoiceLedgerLambdaQueryWrapper.ge(InvoiceLedger::getCreateTime, startOfMonth)
                    .lt(InvoiceLedger::getCreateTime, startOfNextMonth);

            // 获取回款金额
            List<ReceiptPayment> receiptPaymentList = receiptPaymentMapper.selectList(receiptPaymentLambdaQueryWrapper);
            //开票金额
            List<InvoiceLedger> invoiceLedgerList = invoiceLedgerMapper.selectList(invoiceLedgerLambdaQueryWrapper);

            // 使用 Stream 求和
            BigDecimal invoiceAmount = invoiceLedgerList.stream()
                    .map(InvoiceLedger::getInvoiceTotal)
                    .filter(Objects::nonNull)
                    .reduce(BigDecimal.ZERO, BigDecimal::add);

            BigDecimal receiptAmount = receiptPaymentList.stream()
                    .map(ReceiptPayment::getReceiptPaymentAmount)
                    .filter(Objects::nonNull)
                    .reduce(BigDecimal.ZERO, BigDecimal::add);

            MonthlyAmountDto monthlyAmount = new MonthlyAmountDto();
            monthlyAmount.setMonth(targetMonth.format(DateTimeFormatter.ofPattern("yyyy-MM")));
            monthlyAmount.setInvoiceAmount(invoiceAmount);
            monthlyAmount.setReceiptAmount(receiptAmount);

            monthlyAmounts.add(monthlyAmount);
        }

        return monthlyAmounts;
    }

    // 内部类用于存储聚合结果
    private static class GroupedCustomer {
        private final Long customerId;
        private final String customerName;
        private BigDecimal totalAmount = BigDecimal.ZERO;

        public GroupedCustomer(Long customerId, String customerName) {
            this.customerId = customerId;
            this.customerName = customerName;
        }

        public void addAmount(BigDecimal amount) {
            if (amount != null) {
                this.totalAmount = this.totalAmount.add(amount);
            }
        }

        public Long getCustomerId() {
            return customerId;
        }

        public String getCustomerName() {
            return customerName;
        }

        public BigDecimal getTotalAmount() {
            return totalAmount;
        }
    }

    /**
     * 下划线命名转驼峰命名
     */
    private String underlineToCamel(String param) {
        if (param == null || "".equals(param.trim())) {
            return "";
        }
        int len = param.length();
        StringBuilder sb = new StringBuilder(len);
        for (int i = 0; i < len; i++) {
            char c = param.charAt(i);
            if (c == '_') {
                if (++i < len) {
                    sb.append(Character.toUpperCase(param.charAt(i)));
                }
            } else {
                sb.append(Character.toLowerCase(c));
            }
        }
        return sb.toString();
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public int deleteSalesLedgerByIds(Long[] ids) {
        List<Long> idList = Arrays.stream(ids)
                .filter(Objects::nonNull)
                .collect(Collectors.toList());

        if (CollectionUtils.isEmpty(idList)) {
            return 0;
        }
        // 1. 先删除子表数据
        LambdaQueryWrapper<SalesLedgerProduct> productWrapper = new LambdaQueryWrapper<>();
        productWrapper.in(SalesLedgerProduct::getSalesLedgerId, idList);
        salesLedgerProductMapper.delete(productWrapper);

        // 2. 再删除主表数据
        return salesLedgerMapper.deleteBatchIds(idList);
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public int addOrUpdateSalesLedger(SalesLedgerDto salesLedgerDto) {
        try {
            // 1. 校验客户信息
            Customer customer = customerMapper.selectById(salesLedgerDto.getCustomerId());
            if (customer == null) {
                throw new BaseException("客户不存在");
            }

            // 2. DTO转Entity
            SalesLedger salesLedger = convertToEntity(salesLedgerDto);
            salesLedger.setCustomerName(customer.getCustomerName());
            salesLedger.setTenantId(customer.getTenantId());

            // 3. 新增或更新主表
            if (salesLedger.getId() == null) {
                String contractNo = generateSalesContractNo();
                salesLedger.setSalesContractNo(contractNo);
                salesLedgerMapper.insert(salesLedger);
            } else {
                salesLedgerMapper.updateById(salesLedger);
            }

            // 4. 处理子表数据
            List<SalesLedgerProduct> productList = salesLedgerDto.getProductData();
            if (productList != null && !productList.isEmpty()) {
                handleSalesLedgerProducts(salesLedger.getId(), productList, salesLedgerDto.getType());
                updateMainContractAmount(
                        salesLedger.getId(),
                        productList,
                        SalesLedgerProduct::getTaxInclusiveTotalPrice,
                        salesLedgerMapper,
                        SalesLedger.class
                );
            }

            // 5. 迁移临时文件到正式目录
            if (salesLedgerDto.getTempFileIds() != null && !salesLedgerDto.getTempFileIds().isEmpty()) {
                migrateTempFilesToFormal(salesLedger.getId(), salesLedgerDto.getTempFileIds());
            }
            return 1;
        } catch (IOException e) {
            throw new BaseException("文件迁移失败: " + e.getMessage());
        }
    }

    // 文件迁移方法

    /**
     * 将临时文件迁移到正式目录
     *
     * @param businessId  业务ID（销售台账ID）
     * @param tempFileIds 临时文件ID列表
     * @throws IOException 文件操作异常
     */
    private void migrateTempFilesToFormal(Long businessId, List<String> tempFileIds) throws IOException {
        if (CollectionUtils.isEmpty(tempFileIds)) {
            return;
        }

        // 构建正式目录路径（按业务类型和日期分组）
        String formalDir = uploadDir + LocalDate.now().format(DateTimeFormatter.ISO_LOCAL_DATE);

        Path formalDirPath = Paths.get(formalDir);

        // 确保正式目录存在（递归创建）
        if (!Files.exists(formalDirPath)) {
            Files.createDirectories(formalDirPath);
        }

        for (String tempFileId : tempFileIds) {
            // 查询临时文件记录
            TempFile tempFile = tempFileMapper.selectById(tempFileId);
            if (tempFile == null) {
                log.warn("临时文件不存在，跳过处理: {}", tempFileId);
                continue;
            }

            // 构建正式文件名（包含业务ID和时间戳，避免冲突）
            String originalFilename = tempFile.getOriginalName();
            String fileExtension = FilenameUtils.getExtension(originalFilename);
            String formalFilename = businessId + "_" +
                    System.currentTimeMillis() + "_" +
                    UUID.randomUUID().toString().substring(0, 8) +
                    (StringUtils.hasText(fileExtension) ? "." + fileExtension : "");

            Path formalFilePath = formalDirPath.resolve(formalFilename);

            try {
                // 执行文件迁移（使用原子操作确保安全性）
                Files.move(
                        Paths.get(tempFile.getTempPath()),
                        formalFilePath,
                        StandardCopyOption.REPLACE_EXISTING,
                        StandardCopyOption.ATOMIC_MOVE
                );
                log.info("文件迁移成功: {} -> {}", tempFile.getTempPath(), formalFilePath);

                // 更新文件记录（关联到业务ID）
                CommonFile fileRecord = new CommonFile();
                fileRecord.setCommonId(businessId);
                fileRecord.setName(originalFilename);
                fileRecord.setUrl(formalFilePath.toString());
                fileRecord.setCreateTime(LocalDateTime.now());
                fileRecord.setType("1");
                commonFileMapper.insert(fileRecord);

                // 删除临时文件记录
                tempFileMapper.deleteById(tempFile);

                log.info("文件迁移成功: {} -> {}", tempFile.getTempPath(), formalFilePath);
            } catch (IOException e) {
                log.error("文件迁移失败: {}", tempFile.getTempPath(), e);
                // 可选择回滚事务或记录失败文件
                throw new IOException("文件迁移异常", e);
            }
        }
    }


    private void handleSalesLedgerProducts(Long salesLedgerId, List<SalesLedgerProduct> products, Integer type) {
        // 按ID分组，区分新增和更新的记录
        Map<Boolean, List<SalesLedgerProduct>> partitionedProducts = products.stream()
                .peek(p -> p.setSalesLedgerId(salesLedgerId))
                .collect(Collectors.partitioningBy(p -> p.getId() != null));

        List<SalesLedgerProduct> updateList = partitionedProducts.get(true);
        List<SalesLedgerProduct> insertList = partitionedProducts.get(false);

        // 执行更新操作
        if (!updateList.isEmpty()) {
            for (SalesLedgerProduct product : updateList) {
                product.setType(type);
                salesLedgerProductMapper.updateById(product);
            }
        }
        // 执行插入操作
        if (!insertList.isEmpty()) {
            for (SalesLedgerProduct salesLedgerProduct : insertList) {
                salesLedgerProduct.setType(type);
                salesLedgerProduct.setNoInvoiceNum(salesLedgerProduct.getQuantity().intValue());
                salesLedgerProduct.setNoInvoiceAmount(salesLedgerProduct.getTaxInclusiveTotalPrice());
                salesLedgerProductMapper.insert(salesLedgerProduct);
            }
        }
    }

    private SalesLedger convertToEntity(SalesLedgerDto dto) {
        SalesLedger entity = new SalesLedger();
        BeanUtils.copyProperties(dto, entity);
        return entity;
    }

    @Transactional(readOnly = true)
    public String generateSalesContractNo() {
        LocalDate currentDate = LocalDate.now();
        String datePart = currentDate.format(DateTimeFormatter.BASIC_ISO_DATE);
        String lockKey = LOCK_PREFIX + datePart;
        String lockValue = Thread.currentThread().getId() + "-" + System.nanoTime(); // 唯一标识锁持有者

        try {
            // 1. 尝试获取分布式锁（循环直到超时）
            long startWaitTime = System.currentTimeMillis();
            while (System.currentTimeMillis() - startWaitTime < LOCK_WAIT_TIMEOUT * 1000) {
                // SET key value NX PX 30000：仅当锁不存在时获取，设置30秒过期
                Boolean locked = redisTemplate.opsForValue().setIfAbsent(lockKey, lockValue, LOCK_EXPIRE_TIME, TimeUnit.SECONDS);
                if (Boolean.TRUE.equals(locked)) {
                    break; // 成功获取锁
                }
                // 短暂休眠避免忙等待
                try {
                    Thread.sleep(100);
                } catch (InterruptedException e) {
                    Thread.currentThread().interrupt();
                    throw new RuntimeException("获取锁时被中断", e);
                }
            }

            if (!redisTemplate.hasKey(lockKey)) {
                throw new RuntimeException("获取合同编号生成锁失败：超时");
            }

            // 2. 查询当天已存在的序列号（与原逻辑一致）
            List<Integer> existingSequences = salesLedgerMapper.selectSequencesByDate(datePart);
            int nextSequence = findFirstMissingSequence(existingSequences);

            return datePart + String.format("%02d", nextSequence);
        } finally {
            // 3. 释放锁（使用Lua脚本保证原子性，避免误删其他线程的锁）
            String luaScript = "if redis.call('GET', KEYS[1]) == ARGV[1] then return redis.call('DEL', KEYS[1]) else return 0 end";
            redisTemplate.execute(
                    new DefaultRedisScript<>(luaScript, Long.class),
                    Collections.singletonList(lockKey),
                    lockValue // 只有持有相同值的线程才能删除锁
            );
        }
    }

    private int findFirstMissingSequence(List<Integer> sequences) {
        if (sequences.isEmpty()) {
            return 1;
        }
        // 排序后查找第一个缺失的正整数（与原逻辑一致）
        sequences.sort(Integer::compareTo);
        int next = 1;
        for (int seq : sequences) {
            if (seq == next) {
                next++;
            } else if (seq > next) {
                break;
            }
        }
        return next;
    }

    public <T, S> void updateMainContractAmount(
            Long mainId,
            List<T> subList,
            Function<T, BigDecimal> amountGetter,
            BaseMapper<S> mainMapper,
            Class<S> mainEntityClass) {

        if (mainId == null || subList == null || subList.isEmpty()) {
            return;
        }

        // 计算子表金额总和
        BigDecimal totalAmount = subList.stream()
                .map(amountGetter)
                .filter(Objects::nonNull)
                .reduce(BigDecimal.ZERO, BigDecimal::add);

        // 构造主表更新对象（支持任意主表类型）
        try {
            S entity = mainEntityClass.getDeclaredConstructor().newInstance();
            Field idField = mainEntityClass.getDeclaredField("id");
            idField.setAccessible(true);
            idField.set(entity, mainId);

            // 设置 contractAmount 字段，注意这里假设字段名为 "contractAmount"
            Field amountField = mainEntityClass.getDeclaredField("contractAmount");
            amountField.setAccessible(true);
            amountField.set(entity, totalAmount);

            mainMapper.updateById(entity);
        } catch (Exception e) {
            throw new RuntimeException("动态更新主表金额失败", e);
        }
    }
}