/*
 * Copyright 2015 the original author or authors.
 *
 * 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 io.spring.issuebot.github;

import java.util.Date;

import org.junit.Rule;
import org.junit.Test;
import org.junit.rules.ExpectedException;
import org.springframework.core.io.UrlResource;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpMethod;
import org.springframework.http.HttpStatus;
import org.springframework.http.MediaType;
import org.springframework.test.web.client.MockRestServiceServer;
import org.springframework.test.web.client.RequestMatcher;
import org.springframework.test.web.client.response.DefaultResponseCreator;
import org.springframework.util.Base64Utils;
import org.springframework.web.client.RestTemplate;

import static org.hamcrest.Matchers.equalTo;
import static org.hamcrest.Matchers.equalToIgnoringCase;
import static org.hamcrest.Matchers.hasSize;
import static org.hamcrest.Matchers.is;
import static org.hamcrest.Matchers.not;
import static org.hamcrest.Matchers.nullValue;
import static org.junit.Assert.assertThat;
import static org.springframework.test.web.client.match.MockRestRequestMatchers.content;
import static org.springframework.test.web.client.match.MockRestRequestMatchers.header;
import static org.springframework.test.web.client.match.MockRestRequestMatchers.method;
import static org.springframework.test.web.client.match.MockRestRequestMatchers.requestTo;
import static org.springframework.test.web.client.response.MockRestResponseCreators.withStatus;
import static org.springframework.test.web.client.response.MockRestResponseCreators.withSuccess;

/**
 * Tests for {@link GitHubTemplate}.
 *
 * @author Andy Wilkinson
 */
public class GitHubTemplateTests {

	private final RestTemplate rest = GitHubTemplate.createDefaultRestTemplate("username",
			"password");

	private final MockRestServiceServer server = MockRestServiceServer
			.createServer(this.rest);

	private GitHubTemplate gitHub = new GitHubTemplate(this.rest, new RegexLinkParser());

	@Rule
	public ExpectedException thrown = ExpectedException.none();

	@Test
	public void noIssues() {
		this.server.expect(requestTo("https://api.github.com/repos/org/repo/issues"))
				.andExpect(method(HttpMethod.GET)).andExpect(basicAuth())
				.andRespond(withSuccess("[]", MediaType.APPLICATION_JSON));
		Page<Issue> issues = this.gitHub.getIssues("org", "repo");
		assertThat(issues.getContent().size(), is(0));
		assertThat(issues.next(), is(nullValue()));
	}

	@Test
	public void singlePageOfIssues() {
		this.server.expect(requestTo("https://api.github.com/repos/org/repo/issues"))
				.andExpect(method(HttpMethod.GET)).andExpect(basicAuth())
				.andRespond(withResource("issues-page-one.json"));
		Page<Issue> issues = this.gitHub.getIssues("org", "repo");
		assertThat(issues.getContent().size(), is(15));
		assertThat(issues.next(), is(nullValue()));
	}

	@Test
	public void multiplePagesOfIssues() {
		HttpHeaders headers = new HttpHeaders();
		headers.set("Link", "<page-two>; rel=\"next\"");
		this.server.expect(requestTo("https://api.github.com/repos/org/repo/issues"))
				.andExpect(method(HttpMethod.GET)).andExpect(basicAuth())
				.andRespond(withResource("issues-page-one.json",
						"Link:<page-two>; rel=\"next\""));
		this.server.expect(requestTo("page-two")).andExpect(method(HttpMethod.GET))
				.andExpect(basicAuth()).andRespond(withResource("issues-page-two.json"));
		Page<Issue> pageOne = this.gitHub.getIssues("org", "repo");
		assertThat(pageOne.getContent().size(), is(15));
		Page<Issue> pageTwo = pageOne.next();
		assertThat(pageTwo, is(not(nullValue())));
		assertThat(pageTwo.getContent().size(), is(15));
	}

	@Test
	public void rateLimited() {
		long reset = System.currentTimeMillis();
		HttpHeaders headers = new HttpHeaders();
		headers.set("X-RateLimit-Remaining", "0");
		headers.set("X-RateLimit-Reset", Long.toString(reset / 1000));
		this.server.expect(requestTo("https://api.github.com/repos/org/repo/issues"))
				.andExpect(method(HttpMethod.GET)).andExpect(basicAuth())
				.andRespond(withStatus(HttpStatus.FORBIDDEN).headers(headers));
		this.thrown.expect(IllegalStateException.class);
		this.thrown.expectMessage(equalToIgnoringCase(
				"Rate limit exceeded. Limit will reset at " + new Date(reset)));
		this.gitHub.getIssues("org", "repo");
	}

	@Test
	public void noComments() {
		this.server.expect(requestTo("commentsUrl")).andExpect(method(HttpMethod.GET))
				.andExpect(basicAuth())
				.andRespond(withSuccess("[]", MediaType.APPLICATION_JSON));
		Page<Comment> comments = this.gitHub.getComments(
				new Issue(null, "commentsUrl", null, null, null, null, null, null));
		assertThat(comments.getContent().size(), is(0));
		assertThat(comments.next(), is(nullValue()));
	}

	@Test
	public void singlePageOfComments() {
		this.server.expect(requestTo("commentsUrl")).andExpect(method(HttpMethod.GET))
				.andExpect(basicAuth())
				.andRespond(withResource("comments-page-one.json"));
		Page<Comment> comments = this.gitHub.getComments(
				new Issue(null, "commentsUrl", null, null, null, null, null, null));
		assertThat(comments.getContent().size(), is(17));
		assertThat(comments.next(), is(nullValue()));
	}

	@Test
	public void multiplePagesOfComments() {
		HttpHeaders headers = new HttpHeaders();
		headers.set("Link", "<page-two>; rel=\"next\"");
		this.server.expect(requestTo("commentsUrl")).andExpect(method(HttpMethod.GET))
				.andExpect(basicAuth()).andRespond(withResource("comments-page-one.json",
						"Link:<page-two>; rel=\"next\""));
		this.server.expect(requestTo("page-two")).andExpect(method(HttpMethod.GET))
				.andExpect(basicAuth())
				.andRespond(withResource("comments-page-two.json"));
		Page<Comment> pageOne = this.gitHub.getComments(
				new Issue(null, "commentsUrl", null, null, null, null, null, null));
		assertThat(pageOne.getContent().size(), is(17));
		Page<Comment> pageTwo = pageOne.next();
		assertThat(pageTwo, is(not(nullValue())));
		assertThat(pageTwo.getContent().size(), is(3));
	}

	@Test
	public void addLabelToIssue() {
		this.server.expect(requestTo("labelsUrl")).andExpect(method(HttpMethod.POST))
				.andExpect(basicAuth())
				.andExpect(content().string("{\"labels\":[\"test\"]}")).andRespond(
						withSuccess("[{\"name\":\"test\"}]", MediaType.APPLICATION_JSON));
		Issue issue = new Issue("issueUrl", null, null, "labelsUrl{/name}", null, null,
				null, null);
		Issue modifiedIssue = this.gitHub.addLabel(issue, "test");
		assertThat(modifiedIssue.getLabels(), hasSize(1));
	}

	@Test
	public void removeLabelFromIssue() {
		this.server.expect(requestTo("labels/test")).andExpect(method(HttpMethod.DELETE))
				.andExpect(basicAuth())
				.andRespond(withSuccess("[]", MediaType.APPLICATION_JSON));
		Issue issue = new Issue(null, null, null, "labels{/name}", null, null, null,
				null);
		Issue modifiedIssue = this.gitHub.removeLabel(issue, "test");
		assertThat(modifiedIssue.getLabels(), hasSize(0));
	}

	@Test
	public void addCommentToIssue() {
		this.server.expect(requestTo("commentsUrl")).andExpect(method(HttpMethod.POST))
				.andExpect(basicAuth())
				.andExpect(content().string("{\"body\":\"A test comment\"}"))
				.andRespond(withResource("new-comment.json"));
		Issue issue = new Issue(null, "commentsUrl", null, null, null, null, null, null);
		Comment comment = this.gitHub.addComment(issue, "A test comment");
		assertThat(comment, is(not(nullValue())));
	}

	@Test
	public void singlePageOfEvents() {
		this.server.expect(requestTo("eventsUrl")).andExpect(method(HttpMethod.GET))
				.andExpect(basicAuth()).andRespond(withResource("events-page-one.json"));
		Page<Event> events = this.gitHub.getEvents(
				new Issue(null, null, "eventsUrl", null, null, null, null, null));
		assertThat(events.getContent().size(), is(12));
		assertThat(events.next(), is(nullValue()));
	}

	@Test
	public void multiplePagesOfEvents() {
		HttpHeaders headers = new HttpHeaders();
		headers.set("Link", "<page-two>; rel=\"next\"");
		this.server.expect(requestTo("eventsUrl")).andExpect(method(HttpMethod.GET))
				.andExpect(basicAuth()).andRespond(withResource("events-page-one.json",
						"Link:<page-two>; rel=\"next\""));
		this.server.expect(requestTo("page-two")).andExpect(method(HttpMethod.GET))
				.andExpect(basicAuth()).andRespond(withResource("events-page-two.json"));
		Page<Event> pageOne = this.gitHub.getEvents(
				new Issue(null, null, "eventsUrl", null, null, null, null, null));
		assertThat(pageOne.getContent().size(), is(12));
		Page<Event> pageTwo = pageOne.next();
		assertThat(pageTwo, is(not(nullValue())));
		assertThat(pageTwo.getContent().size(), is(3));
	}

	@Test
	public void closeIssue() {
		this.server.expect(requestTo("issueUrl")).andExpect(method(HttpMethod.PATCH))
				.andExpect(basicAuth())
				.andExpect(content().string("{\"state\":\"closed\"}"))
				.andRespond(withSuccess("{\"url\":\"updatedIssueUrl\"}",
						MediaType.APPLICATION_JSON));
		Issue closedIssue = this.gitHub
				.close(new Issue("issueUrl", null, null, null, null, null, null, null));
		assertThat(closedIssue.getUrl(), is(equalTo("updatedIssueUrl")));
	}

	private DefaultResponseCreator withResource(String resource, String... headers) {
		HttpHeaders httpHeaders = new HttpHeaders();
		for (String header : headers) {
			String[] components = header.split(":");
			httpHeaders.set(components[0], components[1]);
		}
		return withSuccess(new UrlResource(getClass().getResource(resource)),
				MediaType.APPLICATION_JSON).headers(httpHeaders);
	}

	private RequestMatcher basicAuth() {
		return header("Authorization", "Basic "
				+ new String(Base64Utils.encode("username:password".getBytes())));
	}

}