/**
 * Copyright (c) 2023, WSO2 LLC. (https://www.wso2.com).
 *
 * WSO2 LLC. 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 com.wso2.openbanking.accelerator.identity.authenticator.util;

import org.apache.commons.lang.StringUtils;
import org.wso2.carbon.identity.application.authentication.framework.context.AuthenticationContext;
import org.wso2.carbon.identity.application.authentication.framework.exception.InvalidCredentialsException;
import org.wso2.carbon.identity.core.util.IdentityUtil;
import org.wso2.carbon.utils.multitenancy.MultitenantUtils;

/**
 * Util methods for OBIdentifierFirstAuthenticator.
 */
public class OBIdentifierAuthUtil {

    /**
     * Add tenant domain to the username.
     *
     * @param username - username
     * @param context  - authentication context
     * @return - processed username
     */
    public static String preprocessUsername(String username, AuthenticationContext context) {
        if (context.getSequenceConfig().getApplicationConfig().isSaaSApp()) {
            return username;
        } else {
            if (IdentityUtil.isEmailUsernameEnabled()) {
                if (StringUtils.countMatches(username, "@") == 1) {
                    return username + "@" + context.getTenantDomain();
                }
            } else if (!username.contains("@")) {
                return username + "@" + context.getTenantDomain();
            }
            return username;
        }
    }

    /**
     * Check if the username exists.
     *
     * @param username - username
     * @param context  -  authentication context
     * @throws InvalidCredentialsException
     */
    public static void validateUsername(String username, AuthenticationContext context)
            throws InvalidCredentialsException {
        if (IdentityUtil.isEmailUsernameEnabled()) {
            String tenantAwareUsername = MultitenantUtils.getTenantAwareUsername(username);
            if (StringUtils.countMatches(tenantAwareUsername, "@") < 1) {
                context.setProperty("InvalidEmailUsername", true);
                throw new InvalidCredentialsException("Invalid username. Username has to be an email.");
            }
        }
    }
}
