/*************************GO-LICENSE-START*********************************
 * Copyright 2014 ThoughtWorks, Inc.
 *
 * 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.
 *************************GO-LICENSE-END***********************************/

package com.thoughtworks.go.server.web;

import java.io.IOException;
import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;

import com.thoughtworks.go.presentation.FlashMessageModel;
import org.junit.Before;
import org.junit.Test;
import org.springframework.mock.web.MockFilterChain;
import org.springframework.mock.web.MockHttpServletRequest;
import org.springframework.mock.web.MockHttpServletResponse;
import org.springframework.mock.web.MockHttpSession;

import static org.hamcrest.Matchers.containsString;
import static org.hamcrest.Matchers.nullValue;
import static org.hamcrest.core.Is.is;
import static org.hamcrest.core.IsNot.not;
import static org.junit.Assert.assertThat;
import static org.junit.Assert.fail;
import static org.mockito.Mockito.mock;

public class FlashLoadingFilterIntegrationTest {
    private FlashLoadingFilter filter;
    private FlashMessageModel flash;
    private FlashMessageService service;
    private String messageKey;

    @Before
    public void setUp() throws ServletException {
        service = new FlashMessageService();
        filter = new FlashLoadingFilter();
        filter.init(null);
        flash = null;
        messageKey = null;
    }

    @Test
    public void shouldInitializeFlashIfNotPresent() throws IOException, ServletException {
        MockHttpServletRequest req = new MockHttpServletRequest();
        MockHttpServletResponse res = new MockHttpServletResponse();

        FilterChain filterChain = new MockFilterChain() {
            @Override public void doFilter(ServletRequest request, ServletResponse response) {
                messageKey = service.add(new FlashMessageModel("my message", "error"));
                flash = service.get(messageKey);
            }
        };
        assertThat(messageKey, is(nullValue()));
        filter.doFilter(req, res, filterChain);
        assertThat(messageKey, not(nullValue()));
        assertThat(flash.toString(), is("my message"));
        assertThat(flash.getFlashClass(), is("error"));
    }

    @Test
    public void shouldLoadExistingFlashFromSession() throws IOException, ServletException {
        MockHttpServletRequest req = new MockHttpServletRequest();
        MockHttpSession session = new MockHttpSession();

        FlashMessageService.Flash oldFlash = new FlashMessageService.Flash();
        oldFlash.put("my_key", new FlashMessageModel("my other message", "warning"));

        session.putValue(FlashLoadingFilter.FLASH_SESSION_KEY, oldFlash);
        req.setSession(session);

        MockHttpServletResponse res = new MockHttpServletResponse();

        FilterChain filterChain = new MockFilterChain() {
            @Override public void doFilter(ServletRequest request, ServletResponse response) {
                flash = service.get("my_key");
            }
        };

        filter.doFilter(req, res, filterChain);
        assertThat(flash.toString(), is("my other message"));
        assertThat(flash.getFlashClass(), is("warning"));
    }

    @Test
    public void shouldClearThreadContext() throws IOException, ServletException {
        MockHttpServletRequest req = new MockHttpServletRequest();
        MockHttpServletResponse res = new MockHttpServletResponse();

        FilterChain filterChain = new MockFilterChain() {
            @Override public void doFilter(ServletRequest request, ServletResponse response) {
                messageKey = service.add(new FlashMessageModel("my message", "error"));
                flash = service.get(messageKey);
            }
        };
        filter.doFilter(req, res, filterChain);
        assertThat(flash.toString(), is("my message"));
        try {
            service.get(messageKey);
            fail("attempt to load flash message should fail, as no thread local is cleared out");
        } catch (Exception e) {
            assertThat(e.getMessage(), is("No flash context found, this call should only be made within a request."));
        }
    }
    
    @Test
    public void shouldClearThreadContextInCaseOfExceptionAsWell() throws IOException, ServletException {
        MockHttpServletRequest req = new MockHttpServletRequest();
        MockHttpServletResponse res = new MockHttpServletResponse();

        FilterChain filterChain = new MockFilterChain() {
            @Override public void doFilter(ServletRequest request, ServletResponse response) {
                messageKey = service.add(new FlashMessageModel("my message", "error"));
                flash = service.get(messageKey);
                throw new RuntimeException("exception here");
            }
        };
        try {
            filter.doFilter(req, res, filterChain);
            fail("exception gobbled");
        } catch (Exception e) {
            assertThat(e.getMessage(), is("exception here"));
        }
        assertThat(flash.toString(), is("my message"));

        try {
            service.get(messageKey);
            fail("attempt to load flash message should fail, as no thread local is cleared out");
        } catch (RuntimeException e) {
            assertThat(e.getMessage(), is("No flash context found, this call should only be made within a request."));
        }
    }
    
    @Test
    public void shouldFailForNonHttpReqeusts() throws IOException, ServletException {
        try {
            filter.doFilter(mock(ServletRequest.class), mock(ServletResponse.class), new MockFilterChain());
            fail("should not process non HTTP requests");
        } catch (Exception e) {
            assertThat(e.getMessage(), containsString("cannot be cast to javax.servlet.http.HttpServletRequest"));
        }
    }
}