// Copyright (C) 2014 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.its.storyboard;

import com.google.gson.Gson;
import com.google.gson.JsonObject;

import org.apache.http.StatusLine;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.Reader;
import java.net.HttpURLConnection;


public class StoryboardClient {

  private static final Logger log =
      LoggerFactory.getLogger(StoryboardClient.class);

  public static final String STORIES_ENDPOINT = "/api/v1/stories";
  public static final String SYS_INFO_ENDPOINT = "/api/v1/systeminfo";
  public static final String TASKS_ENDPOINT = "/api/v1/tasks";

  private final String baseUrl;
  private final String password;

  public StoryboardClient(final String baseUrl, String password) {
    this.baseUrl = baseUrl;
    this.password = password;
  }

  // generic method to get data from a REST endpoint
  public String getData(final String url) throws IOException {

    HttpGet httpget = new HttpGet(url);
    try (CloseableHttpClient client = HttpClients.createDefault();
        CloseableHttpResponse response = client.execute(httpget)) {
      log.debug("Making request for " + httpget.getRequestLine());
      StatusLine sl = response.getStatusLine();
      int responseCode = sl.getStatusCode();
      if (responseCode == HttpURLConnection.HTTP_OK) {
        log.debug("Retreiving data from response " + httpget.getRequestLine());
        InputStream inputStream = response.getEntity().getContent();
        Reader reader = new InputStreamReader(inputStream);
        int contentLength = (int) response.getEntity().getContentLength();
        char[] charArray = new char[contentLength];
        reader.read(charArray);
        String responseJson = new String(charArray);
        log.debug("Data retreived: " + responseJson);
        return responseJson;
      } else {
        log.error("Failed request: " + httpget.getRequestLine()
            + " with response: " + responseCode);
      }
    }
    return null;
  }

  // generic method to POST data with a REST endpoint
  public void postData(final String url, final String data) throws IOException {

    HttpPost httpPost = new HttpPost(url);
    httpPost.addHeader("Authorization", "Bearer " + password);
    httpPost.addHeader("Content-Type", "application/json; charset=utf-8");
    httpPost.setEntity(new StringEntity(data, "utf-8"));
    try (CloseableHttpClient httpclient = HttpClients.createDefault();
        CloseableHttpResponse response = httpclient.execute(httpPost)) {
      log.debug("Executing request " + httpPost.getRequestLine());
      int responseCode = response.getStatusLine().getStatusCode();
      if (responseCode == HttpURLConnection.HTTP_OK) {
        log.info("Updated " + url + " with " + data);
      } else {
        log.error("Failed to post, response: " + responseCode + " ("
            + response.getStatusLine().getReasonPhrase() + ")");
      }
    }
  }

  public String getSysInfo() throws IOException {
    return getData(this.baseUrl + SYS_INFO_ENDPOINT);
  }

  public String getStory(final String id) throws IOException {
    return getData(this.baseUrl + STORIES_ENDPOINT + "/" + getStoryId(id));
  }

  public int getStoryId(final String issueId) throws IOException {
    String taskJson = getTask(issueId);
    JsonObject jobj = new Gson().fromJson(taskJson, JsonObject.class);
    return jobj.get("story_id").getAsInt();
  }

  public String getTask(final String issueId) throws IOException {
    return getData(this.baseUrl + TASKS_ENDPOINT + "/" + issueId);
  }

  public void addComment(final String issueId, final String comment)
      throws IOException {
    int story_id = getStoryId(issueId);
    log.debug("Posting comment with data: ({},{})", story_id, comment);
    final String url =
        baseUrl + STORIES_ENDPOINT + "/" + story_id + "/comments";
    final String escapedComment = comment.replace("\n", "\\n");
    final String json = "{\"story_id\":\"" + issueId + "\",\"content\":\""
        + escapedComment + "\"}";

    postData(url, json);
  }
}