package fr.obeo.tools.stuart.mattermost;

import java.io.IOException;
import java.util.List;

import javax.net.ssl.HostnameVerifier;
import javax.net.ssl.SSLSession;

import com.google.common.base.Splitter;
import com.google.common.collect.Lists;
import com.google.gson.FieldNamingPolicy;
import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import com.squareup.okhttp.Call;
import com.squareup.okhttp.FormEncodingBuilder;
import com.squareup.okhttp.HttpUrl;
import com.squareup.okhttp.OkHttpClient;
import com.squareup.okhttp.Request;
import com.squareup.okhttp.RequestBody;
import com.squareup.okhttp.Response;

import fr.obeo.tools.stuart.MattermostPost;

public class MattermostEmitter {

	private String scheme;
	private String host;
	private String channel;
	private Gson gson;
	private OkHttpClient client;

	public MattermostEmitter(String scheme, String host, String channel) {
		this.scheme = scheme;
		this.host = host;
		this.channel = channel;
		this.gson = new GsonBuilder().disableHtmlEscaping()
				.setFieldNamingPolicy(FieldNamingPolicy.LOWER_CASE_WITH_UNDERSCORES).setPrettyPrinting()
				.serializeNulls().create();
		this.client = new OkHttpClient();
		this.client.setHostnameVerifier(new HostnameVerifier() {

			@Override
			public boolean verify(String hostname, SSLSession session) {
				return true;
			}
		});
	}

	public void accept(MattermostPost inPost) {
		List<MattermostPost> toSend = Lists.newArrayList();
		/*
		 * the actual limit is 4000 in mattermost.
		 */
		if (inPost.getText().length() > 3900) {

			for (String subPost : Splitter.fixedLength(3900).split(inPost.getText())) {
				MattermostPost splitPost = new MattermostPost(subPost, inPost.getUsername(), inPost.getIconUrl());
				toSend.add(splitPost);
			}
		} else {
			toSend.add(inPost);
		}

		for (MattermostPost post : toSend) {
			RequestBody body = new FormEncodingBuilder().add("payload", gson.toJson(post)).build();

			HttpUrl url = new HttpUrl.Builder().scheme(scheme).host(host).addPathSegment("hooks")
					.addPathSegment(channel).build();
			System.out.println(url);
			Request request = new Request.Builder().url(url).post(body).build();
			Response response;
			try {
				Call call = client.newCall(request);
				response = call.execute();
				if (!response.isSuccessful()) {
					throw new IOException("Unexpected code " + response + " canceled ?:" + call.isCanceled());
				}
				System.out.println(response.message());
				response.body().close();
			} catch (IOException e) {
				System.out.println("Message was length:" + post.getText().length() + "\n" + post);
				throw new RuntimeException(e);
			}

		}

	}

}

package fr.obeo.tools.stuart.mattermost;

import java.io.IOException;
import java.util.List;

import javax.net.ssl.HostnameVerifier;
import javax.net.ssl.SSLSession;

import com.google.common.base.Splitter;
import com.google.common.collect.Lists;
import com.google.gson.FieldNamingPolicy;
import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import com.squareup.okhttp.Call;
import com.squareup.okhttp.FormEncodingBuilder;
import com.squareup.okhttp.HttpUrl;
import com.squareup.okhttp.OkHttpClient;
import com.squareup.okhttp.Request;
import com.squareup.okhttp.RequestBody;
import com.squareup.okhttp.Response;

import fr.obeo.tools.stuart.MattermostPost;

public class MattermostEmitter {

	private String scheme;
	private String host;
	private String channel;
	private Gson gson;
	private OkHttpClient client;

	public MattermostEmitter(String scheme, String host, String channel) {
		this.scheme = scheme;
		this.host = host;
		this.channel = channel;
		this.gson = new GsonBuilder().disableHtmlEscaping()
				.setFieldNamingPolicy(FieldNamingPolicy.LOWER_CASE_WITH_UNDERSCORES).setPrettyPrinting()
				.serializeNulls().create();
		this.client = new OkHttpClient();
		this.client.setHostnameVerifier(new HostnameVerifier() {

			@Override
			public boolean verify(String hostname, SSLSession session) {
				return true;
			}
		});
	}

	public void accept(MattermostPost inPost) {
		List<MattermostPost> toSend = Lists.newArrayList();
		/*
		 * the actual limit is 4000 in mattermost.
		 */
		if (inPost.getText().length() > 3900) {

			for (String subPost : Splitter.fixedLength(3900).split(inPost.getText())) {
				MattermostPost splitPost = new MattermostPost(subPost, inPost.getUsername(), inPost.getIconUrl());
				toSend.add(splitPost);
			}
		} else {
			toSend.add(inPost);
		}

		for (MattermostPost post : toSend) {
			String payload = gson.toJson(post);
			RequestBody body = new FormEncodingBuilder().add("payload", payload).build();

			HttpUrl url = new HttpUrl.Builder().scheme(scheme).host(host).addPathSegment("hooks")
					.addPathSegment(channel).build();
			System.out.println(url);
			Request request = new Request.Builder().url(url).post(body).build();
			Response response;
			try {
				Call call = client.newCall(request);
				response = call.execute();
				if (!response.isSuccessful()) {
					throw new IOException("Unexpected code " + response + " canceled ?:" + call.isCanceled() + " payload:\n" + payload + "\n");
				}
				System.out.println(response.message());
				response.body().close();
			} catch (IOException e) {
				System.out.println("Message was length:" + post.getText().length() + "\n" + post);
				throw new RuntimeException(e);
			}

		}

	}

}

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