package me.chanjar.weixin.common.util.http;

import me.chanjar.weixin.common.bean.result.WxError;
import me.chanjar.weixin.common.exception.WxErrorException;
import me.chanjar.weixin.common.util.StringUtils;
import me.chanjar.weixin.common.util.fs.FileUtils;
import org.apache.http.Header;
import org.apache.http.HttpHost;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.config.RequestConfig;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.entity.ContentType;
import org.apache.http.impl.client.CloseableHttpClient;

import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

/**
 * 下载媒体文件请求执行器，请求的参数是String, 返回的结果是File
 * @author Daniel Qian
 *
 */
public class MediaDownloadRequestExecutor implements RequestExecutor<File, String> {
	
  private File tmpDirFile;

  public MediaDownloadRequestExecutor() {
    super();
  }

  public MediaDownloadRequestExecutor(File tmpDirFile) {
    super();
    this.tmpDirFile = tmpDirFile;
  }
  

  @Override
  public File execute(CloseableHttpClient httpclient, HttpHost httpProxy, String uri, String queryParam) throws WxErrorException, ClientProtocolException, IOException {
    if (queryParam != null) {
      if (uri.indexOf('?') == -1) {
        uri += '?';
      }
      uri += uri.endsWith("?") ? queryParam : '&' + queryParam;
    }
    
    HttpGet httpGet = new HttpGet(uri);
    if (httpProxy != null) {
      RequestConfig config = RequestConfig.custom().setProxy(httpProxy).build();
      httpGet.setConfig(config);
    }

    try (CloseableHttpResponse response = httpclient.execute(httpGet)) {

      Header[] contentTypeHeader = response.getHeaders("Content-Type");
      if (contentTypeHeader != null && contentTypeHeader.length > 0) {
        // 下载媒体文件出错
        if (ContentType.TEXT_PLAIN.getMimeType().equals(contentTypeHeader[0].getValue())) {
          String responseContent = Utf8ResponseHandler.INSTANCE.handleResponse(response);
          throw new WxErrorException(WxError.fromJson(responseContent));
        }
      }
      InputStream inputStream = InputStreamResponseHandler.INSTANCE.handleResponse(response);

      // 视频文件不支持下载
      String fileName = getFileName(response);
      if (StringUtils.isBlank(fileName)) {
        return null;
      }
      String[] name_ext = fileName.split("\\.");
      File localFile = FileUtils.createTmpFile(inputStream, name_ext[0], name_ext[1], tmpDirFile);
      return localFile;

    }finally {
      httpGet.releaseConnection();
    }

  }

  protected String getFileName(CloseableHttpResponse response) {
    Header[] contentDispositionHeader = response.getHeaders("Content-disposition");
    Pattern p = Pattern.compile(".*filename=\"(.*)\"");
    Matcher m = p.matcher(contentDispositionHeader[0].getValue());
    m.matches();
    String fileName = m.group(1);
    return fileName;
  }
  
}
