package com.mystarvindata.vindata.utils;

import com.mystarvindata.vindata.config.CloudConfig;
import com.tencentcloudapi.common.Credential;
import com.tencentcloudapi.common.profile.ClientProfile;
import com.tencentcloudapi.common.profile.HttpProfile;
import com.tencentcloudapi.dlc.v20210125.DlcClient;
import com.tencentcloudapi.dlc.v20210125.models.*;
import lombok.RequiredArgsConstructor;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Component;

import java.nio.charset.StandardCharsets;
import java.util.*;

@Slf4j
@Component
@RequiredArgsConstructor
public class WeDataUtils {

    private final CloudConfig.WeDataConfig weDataConfig;

    private static final long POLL_INTERVAL_MS = 1000;
    private static final long MAX_WAIT_MS = 300_000;

    public List<Map<String, Object>> queryWeData(String sql, List<Object> params) {
        if (params != null && !params.isEmpty()) {
            sql = applyParams(sql, params);
        }

        try {
            DlcClient dlcClient = buildDlcClient();

            String taskId = submitTask(dlcClient, sql);
            log.info("WeData DLC task submitted, taskId={}", taskId);

            TaskResultInfo resultInfo = pollTaskResult(dlcClient, taskId);

            return parseResultSet(resultInfo);
        } catch (Exception e) {
            log.error("WeData DLC query failed, sql={}", sql, e);
            return new ArrayList<>();
        }
    }

    public List<Map<String, Object>> queryWeData(String sql) {
        return queryWeData(sql, null);
    }

    private DlcClient buildDlcClient() {
        Credential credential = new Credential(
                weDataConfig.getAccessKey(),
                weDataConfig.getSecretKey()
        );

        HttpProfile httpProfile = new HttpProfile();
        httpProfile.setEndpoint(
                weDataConfig.getEndpoint() != null
                        ? weDataConfig.getEndpoint()
                        : "dlc.tencentcloudapi.com"
        );

        ClientProfile clientProfile = new ClientProfile();
        clientProfile.setHttpProfile(httpProfile);

        String region = weDataConfig.getRegion() != null
                ? weDataConfig.getRegion()
                : "ap-shanghai";

        return new DlcClient(credential, region, clientProfile);
    }

    private String submitTask(DlcClient dlcClient, String sql) throws Exception {
        String encodedSql = Base64.getEncoder().encodeToString(
                sql.getBytes(StandardCharsets.UTF_8)
        );


        SQLTask sqlTask = new SQLTask();
        sqlTask.setSQL(encodedSql);

        Task task = new Task();
        task.setSparkSQLTask(sqlTask);
//        task.setSQLTask(sqlTask);


        CreateTaskRequest request = new CreateTaskRequest();
        request.setTask(task);
//        request.setDatasourceConnectionName("gen6_prod_aiag");

        request.setDataEngineName("gen6_prod_aiag");
        request.setDatabaseName("dws");

        CreateTaskResponse response = dlcClient.CreateTask(request);
        return response.getTaskId();
    }

    private TaskResultInfo pollTaskResult(DlcClient dlcClient, String taskId) throws Exception {
        long startTime = System.currentTimeMillis();

        while (true) {
            DescribeTaskResultRequest request = new DescribeTaskResultRequest();
            request.setTaskId(taskId);
            request.setMaxResults(1000L);

            DescribeTaskResultResponse response = dlcClient.DescribeTaskResult(request);
            TaskResultInfo taskInfo = response.getTaskInfo();
            Long state = taskInfo.getState();

            // 2=success
            if (state != null && state == 2L) {
                return taskInfo;
            }
            // -1=failed, -3=cancelled
            if (state != null && (state == -1L || state == -3L)) {
                throw new RuntimeException(
                        "WeData DLC task failed, state=" + state
                                + ", message=" + taskInfo.getOutputMessage()
                );
            }

            if (System.currentTimeMillis() - startTime > MAX_WAIT_MS) {
                throw new RuntimeException(
                        "WeData DLC task timeout after " + MAX_WAIT_MS + "ms, taskId=" + taskId
                );
            }

            Thread.sleep(POLL_INTERVAL_MS);
        }
    }

    private List<Map<String, Object>> parseResultSet(TaskResultInfo resultInfo) {
        List<Map<String, Object>> resultList = new ArrayList<>();

        Column[] schema = resultInfo.getResultSchema();
        String resultSet = resultInfo.getResultSet();

        if (schema == null || resultSet == null || resultSet.isEmpty()) {
            return resultList;
        }

        String[] columnNames = new String[schema.length];
        for (int i = 0; i < schema.length; i++) {
            columnNames[i] = schema[i].getName();
        }

        // ResultSet is a JSON string: array of arrays, e.g. [["val1","val2"],["val3","val4"]]
        resultSet = resultSet.trim();
        if (!resultSet.startsWith("[")) {
            return resultList;
        }

        // Parse the JSON array of arrays manually to avoid extra dependencies
        // Format: [["v1","v2"],["v3","v4"]]
        List<List<String>> rows = parseJsonArrayOfArrays(resultSet);
        for (List<String> row : rows) {
            Map<String, Object> map = new HashMap<>();
            for (int i = 0; i < columnNames.length && i < row.size(); i++) {
                map.put(columnNames[i], row.get(i));
            }
            resultList.add(map);
        }

        return resultList;
    }

    private List<List<String>> parseJsonArrayOfArrays(String json) {
        List<List<String>> result = new ArrayList<>();
        // Use hutool or simple JSON parsing
        // The SDK returns format: [["a","b"],["c","d"]]
        try {
            cn.hutool.json.JSONArray outerArray = new cn.hutool.json.JSONArray(json);
            for (int i = 0; i < outerArray.size(); i++) {
                cn.hutool.json.JSONArray innerArray = outerArray.getJSONArray(i);
                List<String> row = new ArrayList<>();
                for (int j = 0; j < innerArray.size(); j++) {
                    Object val = innerArray.get(j);
                    row.add(val == null ? null : val.toString());
                }
                result.add(row);
            }
        } catch (Exception e) {
            log.warn("Failed to parse DLC result set JSON", e);
        }
        return result;
    }

    private String applyParams(String sql, List<Object> params) {
        StringBuilder sb = new StringBuilder();
        int paramIndex = 0;
        for (int i = 0; i < sql.length(); i++) {
            char c = sql.charAt(i);
            if (c == '?' && paramIndex < params.size()) {
                Object param = params.get(paramIndex++);
                if (param == null) {
                    sb.append("NULL");
                } else if (param instanceof Number) {
                    sb.append(param);
                } else {
                    sb.append('\'').append(param.toString().replace("'", "''")).append('\'');
                }
            } else {
                sb.append(c);
            }
        }
        return sb.toString();
    }
}