package net.curisit.securis;

import java.io.File;
import java.io.IOException;

import net.curisit.securis.beans.LicenseBean;
import net.curisit.securis.beans.RequestBean;
import net.curisit.securis.utils.JsonUtils;
import net.curisit.securis.utils.Params;

import org.apache.commons.io.FileUtils;

/**
 * Manage all licenses tasks, just like, validation, sync, requesting, ...
 * 
 * @author roberto <roberto.sanchez@curisit.net>
 */
public class LicenseManager {

	private static LicenseManager singleton = new LicenseManager();

	private LicenseManager() {
	}

	public static LicenseManager getInstance() {
		return singleton;
	}

	/**
	 * Validates the license stored in {@code licFile} and get the corresponding LicenseBean
	 * <p>
	 * The validation includes:
	 * <ul>
	 * <li>Signature</li>
	 * <li>HW data</li>
	 * <li>Logo CRC</li>
	 * </ul>
	 * </p>
	 * 
	 * @param licFile
	 * @param appCode
	 * @param customerCode
	 * @return
	 * @throws SeCurisException
	 */
	public LicenseBean validateLicense(File licFile) throws SeCurisException {
		LicenseBean licBean;
		try {
			licBean = JsonUtils.json2object(FileUtils.readFileToString(licFile), LicenseBean.class);
		} catch (IOException e) {
			throw new SeCurisException("Error getting license data from file: " + licFile, e);
		}
		SignatureHelper.getInstance().validateSignature(licBean);
		LicenseValidator.getInstance().validateHW(licBean, Params.get(Params.KEYS.APPLICATION_CODE), Params.get(Params.KEYS.CUSTOMER_CODE));
		LicenseValidator.getInstance().validateLogo(licBean);

		return licBean;
	}

	/**
	 * Creates a new request file with current hardware in the File passed as paramter
	 * 
	 * @param outputRequestFile
	 *            File where the request data will be saved
	 * @return The generated request bean
	 * @throws SeCurisException
	 */
	public RequestBean createRequestFile(File outputRequestFile) throws SeCurisException {
		RequestBean req = ReqGenerator.getInstance().createRequest(Params.get(Params.KEYS.APPLICATION_CODE), Params.get(Params.KEYS.CUSTOMER_CODE));

		ReqGenerator.getInstance().save(req, outputRequestFile);

		return req;
	}

	/**
	 * Send the current license file to server, which is previously validated, to get a renewed one if it is prepared in server side.
	 * 
	 * @param licenseFile
	 *            Current and valid License file
	 * @return New license bean if server creates a new one, otherwise the same current License bean will be returned
	 * @throws SeCurisException
	 */
	public LicenseBean sync(File licenseFile) throws SeCurisException {
		LicenseBean lic = validateLicense(licenseFile);
		// TODO: Send the current LicenseBean to server to check if a new one is prepared.
		return lic;
	}

}