/**
 * Licensed to the Apache Software Foundation (ASF) under one or more contributor license
 * agreements. See the NOTICE file distributed with this work for additional information regarding
 * copyright ownership. The ASF licenses this file to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance with the License. You may obtain a
 * copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software distributed under the License
 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
 * or implied. See the License for the specific language governing permissions and limitations under
 * the License.
 */
package org.apache.iotdb.db.metrics.ui;

import com.codahale.metrics.MetricRegistry;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.URL;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.List;
import org.apache.iotdb.db.conf.IoTDBConstant;
import org.apache.iotdb.db.metrics.server.SqlArgument;
import org.apache.iotdb.db.service.TSServiceImpl;
import org.apache.iotdb.service.rpc.thrift.TSExecuteStatementResp;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class MetricsPage {

  private static final Logger logger = LoggerFactory.getLogger(MetricsPage.class);
  private MetricRegistry mr;
  private final List<SqlArgument> sqlArguments = TSServiceImpl.getSqlArgumentList();

  public MetricsPage(MetricRegistry metricRegistry) {
    this.mr = metricRegistry;
  }

  public String render() {
    String html = "";
    String tmpStr = "";
    try {
      URL resource = MetricsPage.class.getClassLoader().getResource("iotdb/ui/static/index.html");
      InputStream is = resource.openStream();
      BufferedReader br = new BufferedReader(new InputStreamReader(is));
      while ((tmpStr = br.readLine()) != null) {
        html += tmpStr;
      }
      is.close();
    } catch (IOException e) {
      logger.error("Response page failed", e);
    }
    html = html.replace("{version}", IoTDBConstant.VERSION);
    
    html = html.replace("{server}", mr.getGauges().get("iot-metrics.host").getValue() + ":"
        + mr.getGauges().get("iot-metrics.port").getValue());
    
    int cpuRatio = (int)mr.getGauges().get("iot-metrics.cpu_ratio").getValue();
    String os = System.getProperty("os.name");
    if(cpuRatio != 500) {
      html = html.replace("{cpu}", mr.getGauges().get("iot-metrics.cores").getValue() + " Total, "
          + cpuRatio + "% CPU Ratio");
    } else {
      html = html.replace("{cpu}", mr.getGauges().get("iot-metrics.cores").getValue() + " Total  "
          + "<font color=\"red\">can't get the cpu ratio,because this OS:["+os+"] is not support</font>");
    }
    
    html = html.replace("{jvm_mem}",mr.getGauges().get("iot-metrics.max_memory").getValue() + "  "
        + mr.getGauges().get("iot-metrics.total_memory").getValue() + "  "
        + mr.getGauges().get("iot-metrics.free_memory").getValue() + " (Max/Total/Free)MB");
    
    html = html.replace("{host_mem}",String.format("%.0f",
        ((int) mr.getGauges().get("iot-metrics.totalPhysical_memory").getValue() / 1024.0))
        + " GB Total,  "+ String.format("%.1f",
        ((int) mr.getGauges().get("iot-metrics.usedPhysical_memory").getValue() / 1024.0))
        + " GB Used");
    
    html = html.replace("{sql_table}", sqlRow());
    return html;
  }

  public StringBuilder sqlRow() {
    StringBuilder table = new StringBuilder();
    SimpleDateFormat sdf = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss:SSS");
    SqlArgument sqlArgument;
    TSExecuteStatementResp resp;
    String errMsg;
    int statusCode;

    synchronized (sqlArguments) {
      for (int i = (sqlArguments.size() - 1); i >= 0; i--) {
        sqlArgument = sqlArguments.get(i);
        resp = sqlArgument.getTSExecuteStatementResp();
        errMsg = resp.getStatus().message;
        statusCode = resp.getStatus().code;
        String status;
        if (statusCode == 200) {
          status = "FINISHED";
        } else if (statusCode == 201) {
          status = "EXECUTING";
        } else if (statusCode == 202) {
          status = "INVALID_HANDLE";
        } else {
          status = "FAILED";
        }

        table.append(
            "<tr>"
                + "<td>" + resp.getOperationType() + "</td>"
                + "<td>" + sdf.format(new Date(sqlArgument.getStartTime())) + "</td>"
                + "<td>" + sdf.format(new Date(sqlArgument.getEndTime())) + "</td>"
                + "<td>" + (int) (sqlArgument.getEndTime() - sqlArgument.getStartTime()) + " ms</td>"
                + "<td class=\"sql\">" + sqlArgument.getStatement() + "</td>"
                + "<td>" + status + "</td>"
                + "<td>" + (errMsg.equals("") ? "== Parsed Physical Plan ==" : errMsg)
                +   "<span class=\"expand-details\" onclick=\"this.parentNode.querySelector('.stacktrace-details').classList.toggle('collapsed')\">+ details</span>"
                +   "<div class=\"stacktrace-details collapsed\">"
                +     "<pre>"
                +       "Physical Plan: " + sqlArgument.getPlan().getClass().getSimpleName()
                +       "</br>===========================</br>"
                +       "OperatorType: " + sqlArgument.getPlan().getOperatorType()
                +       "</br>===========================</br>"
                +       "Path: " + sqlArgument.getPlan().getPaths().toString()
                +     "</pre>"
                +   "</div>"
                + "</td>"
                +"</tr>");
      }
    }
    return table;
  }

}
