/*
 *  Copyright 2020 Anyware Services
 *
 *  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 org.ametys.plugins.workspaces.documents.onlyoffice;

import java.util.HashMap;
import java.util.Map;
import java.util.Set;

import org.apache.avalon.framework.component.Component;
import org.apache.avalon.framework.service.ServiceException;
import org.apache.avalon.framework.service.ServiceManager;
import org.apache.avalon.framework.service.Serviceable;
import org.apache.commons.lang3.StringUtils;

import org.ametys.core.authentication.token.AuthenticationTokenManager;
import org.ametys.core.ui.Callable;
import org.ametys.core.user.CurrentUserProvider;
import org.ametys.plugins.explorer.resources.Resource;
import org.ametys.plugins.repository.AmetysObjectResolver;
import org.ametys.runtime.config.Config;
import org.ametys.runtime.plugin.component.AbstractLogEnabled;

import com.auth0.jwt.JWT;
import com.auth0.jwt.algorithms.Algorithm;

/**
 * Main helper for OnlyOffice edition
 */
public class OnlyOfficeManager extends AbstractLogEnabled implements Component, Serviceable
{
    /** The Avalon role */
    public static final String ROLE = OnlyOfficeManager.class.getName();
    
    /** The token manager */
    protected AuthenticationTokenManager _tokenManager;
    /** The current user provider */
    protected CurrentUserProvider _currentUserProvider;
    /** The Ametys object resolver */
    protected AmetysObjectResolver _resolver;
    /** The Only Office key manager */
    protected OnlyOfficeKeyManager _onlyOfficeKeyManager;
    
    @Override
    public void service(ServiceManager manager) throws ServiceException
    {
        _currentUserProvider = (CurrentUserProvider) manager.lookup(CurrentUserProvider.ROLE);
        _tokenManager = (AuthenticationTokenManager) manager.lookup(AuthenticationTokenManager.ROLE);
        _resolver = (AmetysObjectResolver) manager.lookup(AmetysObjectResolver.ROLE);
        _onlyOfficeKeyManager = (OnlyOfficeKeyManager) manager.lookup(OnlyOfficeKeyManager.ROLE);
    }
    
    /**
     * Determines if OnlyOffice edition is available
     * @return true if OnlyOffice edition is available
     */
    @Callable
    public boolean isOnlyOfficeEditionAvailable()
    {
        return Config.getInstance().getValue("workspaces.onlyoffice.enabled", false, false);
    }
    
    /**
     * Get the needed information for Only Office edition
     * @param resourceId the id of resource to edit
     * @return the only office informations
     */
    @Callable
    public Map<String, Object> getOnlyOfficeInfo(String resourceId)
    {
        Map<String, Object> infos = new HashMap<>();
        
        Resource resource = _resolver.resolveById(resourceId);
        
        String token = generateToken(resourceId);
        String tokenCtx = StringUtils.substringAfter(resourceId, "://");
        
        Map<String, Object> fileInfo = new HashMap<>();
        fileInfo.put("title", resource.getName());
        fileInfo.put("fileExtension", StringUtils.substringAfterLast(resource.getName(), ".").toLowerCase());
        fileInfo.put("key", _onlyOfficeKeyManager.getKey(resourceId));
        
        String ooCMSUrl = Config.getInstance().getValue("workspaces.onlyoffice.bo.url");
        if (StringUtils.isEmpty(ooCMSUrl))
        {
            ooCMSUrl = Config.getInstance().getValue("cms.url");
        }
        
        String downloadUrl = ooCMSUrl
                + "/_workspaces/only-office/download-resource?"
                + "id=" + resourceId
                + "&token=" + token
                + "&tokenContext=" + tokenCtx;
        
        fileInfo.put("urlDownload", downloadUrl);
        
        infos.put("file", fileInfo);
        
        String callbackUrl = ooCMSUrl
                + "/_workspaces/only-office/response.json?"
                + "id=" + resourceId
                + "&token=" + token
                + "&tokenContext=" + tokenCtx;
        
        infos.put("callbackUrl", callbackUrl);
        
        return infos;
    }
    /**
     * Generate a token for OnlyOffice use
     * @param fileId id of the resource that will be used by OnlyOffice
     * @return the token
     */
    @Callable
    public String generateToken(String fileId)
    {
        Set<String> contexts = Set.of(StringUtils.substringAfter(fileId, "://"));
        
        return _tokenManager.generateToken(_currentUserProvider.getUser(), 30000, true, null, contexts, "onlyOfficeResponse", null);
    }
    
    /**
     * Sign a json configuration for OnlyOffice using a secret parametrized key
     * @param toSign The json to sign
     * @return The signed json
     */
    @Callable
    public Map<String, Object> signConfiguration(String toSign)
    {
        String secret = Config.getInstance().getValue("workspaces.onlyoffice.secret");
        
        Map<String, Object> result = new HashMap<>();
        
        if (StringUtils.isNotBlank(secret))
        {
            Algorithm algorithm = Algorithm.HMAC256(secret);
            String token = JWT.create()
                    .withIssuer(toSign)
                    .sign(algorithm);
            result.put("signature", token);
        }
        
        result.put("success", "true");
        return result;
    }
}