package org.gcube.gcat.utils;

import java.io.InputStream;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.Map;
import java.util.Properties;

import javax.ws.rs.InternalServerErrorException;
import javax.ws.rs.WebApplicationException;

import org.gcube.common.authorization.utils.manager.SecretManager;
import org.gcube.common.authorization.utils.secret.Secret;
import org.gcube.common.authorization.utils.secret.SecretUtility;
import org.gcube.common.keycloak.KeycloakClientFactory;
import org.gcube.common.keycloak.model.TokenResponse;

/**
 * @author Luca Frosini (ISTI - CNR)
 */
public class Constants {
	
	public static final String CATALOGUE_NAME = "gCat";
	
	private static final String PROPERTY_FILENAME = "config.properties";
	/*
	 * Key : Context
	 * Value : Application Token
	 */
	protected static final Map<String,String> applicationTokens;
	
	static {
		try {
			applicationTokens = new HashMap<>();
			Properties properties = new Properties();
			InputStream input = Constants.class.getClassLoader().getResourceAsStream(PROPERTY_FILENAME);
			// load a properties file
			properties.load(input);
			Enumeration<?> enumeration = properties.propertyNames();
			while(enumeration.hasMoreElements()) {
				String context = (String) enumeration.nextElement();
				String applicationToken = properties.getProperty(context);
				applicationTokens.put(context, applicationToken);
			}
		} catch(Exception e) {
			throw new WebApplicationException(e);
		}
	}
	
	@Deprecated
	private static String getCatalogueApplicationToken() {
		String context = SecretManager.instance.get().getContext();
		try {
			return applicationTokens.get(context);
		} catch(Exception e) {
			throw new InternalServerErrorException(
					"Unable to retrieve Application Token for context " + context, e);
		}
	}
	
	private static final String CLIENT_SECRET_FILENAME = "clientSecret";
	private static final String CLIENT_ID = "gcat";
	protected static String clientSecret;
	
	private static String getClientSecret(String context) {
		try {
			if(clientSecret==null) {
				Properties properties = new Properties();
				InputStream input = Constants.class.getClassLoader().getResourceAsStream(CLIENT_SECRET_FILENAME);
				properties.load(input);
				String root = context.substring(0, context.indexOf('/', 1));
				clientSecret = properties.getProperty(root);
			}
			return clientSecret;
		} catch(Exception e) {
			throw new InternalServerErrorException(
					"Unable to retrieve Application Token for context " + SecretManager.instance.get().getContext(), e);
		}
	}
	
	private static String getJWTAccessToken() throws Exception {
		String contextToAuthorise = SecretManager.instance.get().getContext();
		TokenResponse tr = KeycloakClientFactory.newInstance().queryUMAToken(CLIENT_ID, getClientSecret(contextToAuthorise), contextToAuthorise, null);
	    return tr.getAccessToken();
	}
	
	public static String getCatalogueSecurityToken() throws Exception {
		try {
			return getJWTAccessToken();
		}catch (Exception e) {
			return getCatalogueApplicationToken();
		}
	}
	
	public static Secret getCatalogueSecret() throws Exception {
		String securityToken = getCatalogueSecurityToken();
		return SecretUtility.getSecretByTokenString(securityToken);
	}
	
}