// Copyright (C) 2015 The Android Open Source Project
//
// Licensed 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 com.googlesource.gerrit.plugins.rabbitmq.config;

import com.google.gerrit.server.util.TimeUtil;
import com.googlesource.gerrit.plugins.rabbitmq.annotation.MessageHeader;
import com.googlesource.gerrit.plugins.rabbitmq.config.section.Message;
import com.googlesource.gerrit.plugins.rabbitmq.config.section.Section;
import com.rabbitmq.client.AMQP;

import org.apache.commons.codec.CharEncoding;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.lang.reflect.Field;
import java.util.Date;
import java.util.HashMap;
import java.util.Map;

public class AMQProperties {

  public final static String EVENT_APPID = "gerrit";
  public final static String CONTENT_TYPE_JSON = "application/json";

  private static final Logger LOGGER = LoggerFactory.getLogger(AMQProperties.class);

  private final PluginProperties properties;
  private AMQP.BasicProperties amqpProperties;

  public AMQProperties(PluginProperties properties) {
    this.properties = properties;
  }

  public AMQP.BasicProperties getBasicProperties() {
    if (amqpProperties == null) {
      Map<String, Object> headers = new HashMap<>();
      for (Section section : properties.getSections()) {
        for (Field f : section.getClass().getFields()) {
          if (f.isAnnotationPresent(MessageHeader.class)) {
            MessageHeader mh = f.getAnnotation(MessageHeader.class);
            try {
              switch(f.getType().getSimpleName()) {
                case "String":
                  headers.put(mh.value(), f.get(section).toString());
                  break;
                case "Integer":
                  headers.put(mh.value(), f.getInt(section));
                  break;
                case "Long":
                  headers.put(mh.value(), f.getLong(section));
                  break;
                case "Boolean":
                  headers.put(mh.value(), f.getBoolean(section));
                  break;
                default:
                  break;
              }
            } catch (Exception ex) {
              LOGGER.info(ex.getMessage());
            }
          }
        }
      }
      Message message = properties.getSection(Message.class);
      amqpProperties = new AMQP.BasicProperties.Builder()
        .appId(EVENT_APPID)
        .contentEncoding(CharEncoding.UTF_8)
        .contentType(CONTENT_TYPE_JSON)
        .deliveryMode(message.deliveryMode)
        .priority(message.priority)
        .headers(headers)
        .timestamp(new Date(TimeUtil.nowMs()))
        .build();
    }
    return amqpProperties;
  }
}