/*
 * Copyright 2011 gitblit.com.
 *
 * 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 com.gitblit;

import java.io.IOException;
import java.text.MessageFormat;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.gitblit.Constants.RpcRequest;
import com.gitblit.models.RepositoryModel;
import com.gitblit.models.UserModel;
import com.gitblit.utils.HttpUtils;
import com.gitblit.utils.RpcUtils;

/**
 * Handles remote procedure calls.
 * 
 * @author James Moger
 * 
 */
public class RpcServlet extends JsonServlet {

	private static final long serialVersionUID = 1L;

	public RpcServlet() {
		super();
	}

	/**
	 * Processes an rpc request.
	 * 
	 * @param request
	 * @param response
	 * @throws javax.servlet.ServletException
	 * @throws java.io.IOException
	 */
	@Override
	protected void processRequest(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		RpcRequest reqType = RpcRequest.fromName(request.getParameter("req"));
		String objectName = request.getParameter("name");
		logger.info(MessageFormat.format("Rpc {0} request from {1}", reqType,
				request.getRemoteAddr()));

		UserModel user = (UserModel) request.getUserPrincipal();

		Object result = null;
		if (RpcRequest.LIST_REPOSITORIES.equals(reqType)) {
			// Determine the Gitblit clone url
			String gitblitUrl = HttpUtils.getGitblitURL(request);
			StringBuilder sb = new StringBuilder();
			sb.append(gitblitUrl);
			sb.append(Constants.GIT_PATH);
			sb.append("{0}");
			String cloneUrl = sb.toString();

			// list repositories
			List<RepositoryModel> list = GitBlit.self().getRepositoryModels(user);
			Map<String, RepositoryModel> repositories = new HashMap<String, RepositoryModel>();
			for (RepositoryModel model : list) {
				String url = MessageFormat.format(cloneUrl, model.name);
				repositories.put(url, model);
			}
			result = repositories;
		} else if (RpcRequest.LIST_USERS.equals(reqType)) {
			// list users
			List<String> names = GitBlit.self().getAllUsernames();
			List<UserModel> users = new ArrayList<UserModel>();
			for (String name : names) {
				users.add(GitBlit.self().getUserModel(name));
			}
			result = users;
		} else if (RpcRequest.CREATE_REPOSITORY.equals(reqType)) {
			// create repository
			RepositoryModel model = deserialize(request, response, RepositoryModel.class);
			try {
				GitBlit.self().updateRepositoryModel(model.name, model, true);
			} catch (GitBlitException e) {
				response.setStatus(failureCode);
			}
		} else if (RpcRequest.EDIT_REPOSITORY.equals(reqType)) {
			// edit repository
			RepositoryModel model = deserialize(request, response, RepositoryModel.class);
			// name specifies original repository name in event of rename
			String repoName = objectName;
			if (repoName == null) {
				repoName = model.name;
			}
			try {
				GitBlit.self().updateRepositoryModel(repoName, model, false);
			} catch (GitBlitException e) {
				response.setStatus(failureCode);
			}
		} else if (RpcRequest.DELETE_REPOSITORY.equals(reqType)) {
			// delete repository
			RepositoryModel model = deserialize(request, response, RepositoryModel.class);
			GitBlit.self().deleteRepositoryModel(model);
		} else if (RpcRequest.CREATE_USER.equals(reqType)) {
			// create user
			UserModel model = deserialize(request, response, UserModel.class);
			try {
				GitBlit.self().updateUserModel(model.username, model, true);
			} catch (GitBlitException e) {
				response.setStatus(failureCode);
			}
		} else if (RpcRequest.EDIT_USER.equals(reqType)) {
			// edit user
			UserModel model = deserialize(request, response, UserModel.class);
			// name parameter specifies original user name in event of rename
			String username = objectName;
			if (username == null) {
				username = model.username;
			}
			try {
				GitBlit.self().updateUserModel(username, model, false);
			} catch (GitBlitException e) {
				response.setStatus(failureCode);
			}
		} else if (RpcRequest.DELETE_USER.equals(reqType)) {
			// delete user
			UserModel model = deserialize(request, response, UserModel.class);
			if (!GitBlit.self().deleteUser(model.username)) {
				response.setStatus(failureCode);
			}
		} else if (RpcRequest.LIST_REPOSITORY_MEMBERS.equals(reqType)) {
			// get repository members
			RepositoryModel model = GitBlit.self().getRepositoryModel(objectName);
			result = GitBlit.self().getRepositoryUsers(model);
		} else if (RpcRequest.SET_REPOSITORY_MEMBERS.equals(reqType)) {
			// update repository access list
			RepositoryModel model = GitBlit.self().getRepositoryModel(objectName);
			Collection<String> names = deserialize(request, response, RpcUtils.NAMES_TYPE);
			List<String> users = new ArrayList<String>(names);
			if (!GitBlit.self().setRepositoryUsers(model, users)) {
				response.setStatus(failureCode);
			}
		} else if (RpcRequest.LIST_FEDERATION_REGISTRATIONS.equals(reqType)) {
			// return the list of federation registrations
			result = GitBlit.self().getFederationRegistrations();
		} else if (RpcRequest.LIST_FEDERATION_RESULTS.equals(reqType)) {
			// return the list of federation result registrations
			if (GitBlit.canFederate()) {
				result = GitBlit.self().getFederationResultRegistrations();
			} else {
				response.sendError(notAllowedCode);
			}
		} else if (RpcRequest.LIST_FEDERATION_PROPOSALS.equals(reqType)) {
			// return the list of federation proposals
			if (GitBlit.canFederate()) {
				result = GitBlit.self().getPendingFederationProposals();
			} else {
				response.sendError(notAllowedCode);
			}
		} else if (RpcRequest.LIST_FEDERATION_SETS.equals(reqType)) {
			// return the list of federation sets
			if (GitBlit.canFederate()) {
				String gitblitUrl = HttpUtils.getGitblitURL(request);
				result = GitBlit.self().getFederationSets(gitblitUrl);
			} else {
				response.sendError(notAllowedCode);
			}
		} else if (RpcRequest.LIST_SETTINGS.equals(reqType)) {
			// return the server's settings
			result = GitBlit.self().getSettingsModel();
		} else if (RpcRequest.LIST_STATUS.equals(reqType)) {
			// return the server's status information
			result = GitBlit.self().getStatus();
		}

		// send the result of the request
		serialize(response, result);
	}
}