/**
*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.apache.airavata.service.security.authzcache;

import org.apache.airavata.common.exception.ApplicationSettingsException;
import org.apache.airavata.security.AiravataSecurityException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class DefaultAuthzCacheManager implements AuthzCacheManager {

    private static final Logger logger = LoggerFactory.getLogger(DefaultAuthzCacheManager.class);

    @Override
    public AuthzCachedStatus getAuthzCachedStatus(AuthzCacheIndex authzCacheIndex) throws AiravataSecurityException {
        if (isAuthzDecisionCached(authzCacheIndex)) {
            AuthzCacheEntry cacheEntry = getAuthzCacheEntry(authzCacheIndex);
            long expiryTime = cacheEntry.getExpiryTime();
            long currentTime = System.currentTimeMillis();
            long timePassed = (currentTime - cacheEntry.getEntryTimestamp()) / 1000;
            if (expiryTime > timePassed) {
                // access token is still valid. Hence, return the cached decision
                if (cacheEntry.getDecision()) {
                    return AuthzCachedStatus.AUTHORIZED;
                } else {
                    return AuthzCachedStatus.NOT_AUTHORIZED;
                }
            } else {
                // access token has been expired. Hence, remove the entry and return.
                removeAuthzCacheEntry(authzCacheIndex);
                return AuthzCachedStatus.NOT_CACHED;
            }
        } else {
            return AuthzCachedStatus.NOT_CACHED;
        }
    }

    @Override
    public void addToAuthzCache(AuthzCacheIndex authzCacheIndex, AuthzCacheEntry authzCacheEntry)
            throws AiravataSecurityException {
        try {
            AuthzCache.getInstance().put(authzCacheIndex, authzCacheEntry);
        } catch (ApplicationSettingsException e) {
            logger.error(e.getMessage(), e);
            throw new AiravataSecurityException("Error in obtaining the authorization cache instance.");
        }
    }

    @Override
    public boolean isAuthzDecisionCached(AuthzCacheIndex authzCacheIndex) throws AiravataSecurityException {
        try {
            return AuthzCache.getInstance().containsKey(authzCacheIndex);
        } catch (ApplicationSettingsException e) {
            logger.error(e.getMessage(), e);
            throw new AiravataSecurityException("Error in obtaining the authorization cache instance.");
        }
    }

    @Override
    public AuthzCacheEntry getAuthzCacheEntry(AuthzCacheIndex authzCacheIndex) throws AiravataSecurityException {
        try {
            return AuthzCache.getInstance().get(authzCacheIndex);
        } catch (ApplicationSettingsException e) {
            logger.error(e.getMessage(), e);
            throw new AiravataSecurityException("Error in obtaining the authorization cache instance.");
        }
    }

    @Override
    public void removeAuthzCacheEntry(AuthzCacheIndex authzCacheIndex) throws AiravataSecurityException {
        try {
            AuthzCache.getInstance().remove(authzCacheIndex);
        } catch (ApplicationSettingsException e) {
            logger.error(e.getMessage(), e);
            throw new AiravataSecurityException("Error in obtaining the authorization cache instance.");
        }
    }

    @Override
    public void clearCache() throws AiravataSecurityException {
        try {
            AuthzCache.getInstance().clear();
        } catch (ApplicationSettingsException e) {
            logger.error(e.getMessage(), e);
            throw new AiravataSecurityException("Error in obtaining the authorization cache instance.");
        }
    }
}
