/*
    * Copyright 2002-2011 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
    *
    *      https://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 org.springframework.security.oauth2.provider.password;
  
  import java.util.LinkedHashMap;
  import java.util.Map;
  
  import org.springframework.security.authentication.AbstractAuthenticationToken;
  import org.springframework.security.authentication.AccountStatusException;
  import org.springframework.security.authentication.AuthenticationManager;
  import org.springframework.security.authentication.BadCredentialsException;
  import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
  import org.springframework.security.core.Authentication;
  import org.springframework.security.oauth2.common.exceptions.InvalidGrantException;
  import org.springframework.security.oauth2.provider.ClientDetails;
  import org.springframework.security.oauth2.provider.ClientDetailsService;
  import org.springframework.security.oauth2.provider.OAuth2Authentication;
  import org.springframework.security.oauth2.provider.OAuth2Request;
  import org.springframework.security.oauth2.provider.OAuth2RequestFactory;
  import org.springframework.security.oauth2.provider.TokenRequest;
  import org.springframework.security.oauth2.provider.token.AbstractTokenGranter;
  import org.springframework.security.oauth2.provider.token.AuthorizationServerTokenServices;
  
  /**
   * @author Dave Syer
   * 
   */
  public class ResourceOwnerPasswordTokenGranter extends AbstractTokenGranter {
  
  	private static final String GRANT_TYPE = "password";
  
  	private final AuthenticationManager authenticationManager;
  
  	public ResourceOwnerPasswordTokenGranter(AuthenticationManager authenticationManager,
  			AuthorizationServerTokenServices tokenServices, ClientDetailsService clientDetailsService, OAuth2RequestFactory requestFactory) {
  		this(authenticationManager, tokenServices, clientDetailsService, requestFactory, GRANT_TYPE);
  	}
  
  	protected ResourceOwnerPasswordTokenGranter(AuthenticationManager authenticationManager, AuthorizationServerTokenServices tokenServices,
  			ClientDetailsService clientDetailsService, OAuth2RequestFactory requestFactory, String grantType) {
  		super(tokenServices, clientDetailsService, requestFactory, grantType);
  		this.authenticationManager = authenticationManager;
  	}
  
  	@Override
  	protected OAuth2Authentication getOAuth2Authentication(ClientDetails client, TokenRequest tokenRequest) {
  
  		Map<String, String> parameters = new LinkedHashMap<String, String>(tokenRequest.getRequestParameters());
  		String username = parameters.get("username");
  		String password = parameters.get("password");
  		// Protect from downstream leaks of password
  		parameters.remove("password");
  
  		Authentication userAuth = new UsernamePasswordAuthenticationToken(username, password);
  		((AbstractAuthenticationToken) userAuth).setDetails(parameters);
  		try {
  			userAuth = authenticationManager.authenticate(userAuth);
  		}
  		catch (AccountStatusException ase) {
  			//covers expired, locked, disabled cases (mentioned in section 5.2, draft 31)
  			throw new InvalidGrantException(ase.getMessage());
  		}
  		catch (BadCredentialsException e) {
  			// If the username/password are wrong the spec says we should send 400/invalid grant
  			throw new InvalidGrantException(e.getMessage());
  		}
  		if (userAuth == null || !userAuth.isAuthenticated()) {
  			throw new InvalidGrantException("Could not authenticate user: " + username);
  		}
  		
  		OAuth2Request storedOAuth2Request = getRequestFactory().createOAuth2Request(client, tokenRequest);		
  		return new OAuth2Authentication(storedOAuth2Request, userAuth);
  	}
  }