package com.dashboard.aws.lambda.handler;

import com.amazonaws.services.lambda.runtime.Context;
import com.amazonaws.services.lambda.runtime.RequestHandler;
import com.dashboard.aws.lambda.Constants;
import com.dashboard.aws.lambda.service.MySQLService;
import com.dashboard.aws.lambda.service.S3Service;
import com.dashboard.aws.lambda.util.CsvUtil;
import com.dashboard.aws.lambda.util.DateUtil;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.time.LocalDate;
import java.time.ZoneId;
import java.util.*;

public class S3ToMySQLHandler implements RequestHandler<Map<String, Object>, String> {

    private static final Logger logger = LoggerFactory.getLogger(S3ToMySQLHandler.class);

    private final MySQLService mysqlService = new MySQLService();
    private final S3Service s3Service = new S3Service();

    @Override
    public String handleRequest(Map<String, Object> event, Context context) {
        try {
            // 同步目标日期（这里同步 3 天前的数据）
//            LocalDate targetDate = LocalDate.now(ZoneId.of("Asia/Tokyo")).minusDays(3);
//            String dateStr = targetDate.format(java.time.format.DateTimeFormatter.ISO_DATE);
//            String dateStr = "2025-10-08";
            ZoneId zone = ZoneId.of("Asia/Tokyo");
            LocalDate now = DateUtil.resolveEventDate( event, zone);
            String dateStr = DateUtil.getLastYearSameIsoWeekDayStr(now);

            // 查询符合条件的企业ID
            List<Long> companyIds = mysqlService.getActiveCompanyIds();
            logger.info("company id list: {}", companyIds);

            List<String> tables = Constants.tables;

            for (Long companyId : companyIds) {
                String schema = "data_center_dongjian_" + companyId;

                for (String table : tables) {
                    // 构造 S3 文件路径
                    String s3Key = String.format("%s/%s/%s.csv", table, companyId, dateStr);
                    logger.info("processing s3 file: {}", s3Key);

                    // 下载 CSV
                    byte[] content = s3Service.download(s3Key);
                    if (content == null || content.length == 0) {
                        logger.warn("[{}][{}] file empty or not found: {}", schema, table, s3Key);
                        continue;
                    }

                    // 解析 CSV
                    List<Map<String, String>> rows = CsvUtil.parseCsv(content);
                    if (rows.isEmpty()) {
                        logger.warn("[{}][{}] csv empty: {}", schema, table, s3Key);
                        continue;
                    }

                    // 插入到 MySQL
                    try {
                        int inserted = mysqlService.insertRows(schema, table, rows);
                        logger.info("[{}][{}] inserted {} rows", schema, table, inserted);
                    } catch (Exception e) {
                        logger.error("[{}][{}] insert failed -> {}", schema, table, s3Key, e);
                    }
                }
            }

            return "sync process finished";

        } catch (Exception e) {
            logger.error("sync error", e);
            return "sync error：" + e.getMessage();
        }
    }
}