package net.curisit.securis;

import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.UnsupportedEncodingException;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.nio.file.StandardOpenOption;

import net.curisit.securis.beans.RequestBean;
import net.curisit.securis.utils.HWInfo;
import net.curisit.securis.utils.JsonUtils;
import net.curisit.securis.utils.LicUtils;

import org.apache.commons.io.IOUtils;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;

public class ReqGenerator {

    private static final Logger LOG = LogManager.getLogger(ReqGenerator.class);

    private static ReqGenerator singleton = new ReqGenerator();

    private ReqGenerator() {
    }

    public static ReqGenerator getInstance() {
        return singleton;
    }

    public RequestBean createRequest(String licTypeCode, String customerCode, String packCode) throws SeCurisException {
        RequestBean req = new RequestBean();

        req.setLicenseTypeCode(licTypeCode);
        req.setCustomerCode(customerCode);
        req.setPackCode(packCode);
        req.setArch(HWInfo.getArch());
        req.setCrcLogo(getCrcLogo());
        req.setMacAddresses(HWInfo.getMACAddress());
        req.setOsName(HWInfo.getOsName());

        return req;
    }

    public RequestBean loadRequest(File requestFile) throws SeCurisException {
        try {
            String json = new String(Files.readAllBytes(Paths.get(requestFile.toURI())), "utf-8");
            RequestBean req = JsonUtils.json2object(json, RequestBean.class);
            return req;
        } catch (IOException e) {
            LOG.error("Request file {} was not found or is not accesible");
            throw new SeCurisException("ERROR accesing request file: " + requestFile.getAbsolutePath(), e);
        }
    }

    /**
     * Generate a request file using a {@link RequestBean}
     * 
     * @param req
     * @param file
     * @throws SeCurisException
     */
    public void save(RequestBean req, File file) throws SeCurisException {
        byte[] json;
        try {
            json = JsonUtils.toPrettyJSON(req).getBytes("utf-8");
            Files.write(Paths.get(file.toURI()), json, StandardOpenOption.CREATE, StandardOpenOption.TRUNCATE_EXISTING);
        } catch (UnsupportedEncodingException e) {
            LOG.error("Error creating json doc from request: " + req, e);
            throw new SeCurisException("Error creating json doc from request: " + req, e);
        } catch (IOException e) {
            LOG.error("Error creating request file: " + file, e);
            throw new SeCurisException("Error creating request file: " + file, e);
        }

        LOG.debug("License saved in {}", file);

    }

    private String getCrcLogo() {
        String logResource = "images/logo_customer.png";
        InputStream is = getClass().getClassLoader().getResourceAsStream(logResource);
        if (is == null)
            return null;
        try {
            String shaLogo = LicUtils.sha256(IOUtils.toByteArray(is), LicenseValidator.LOGO_SECRET);
            return shaLogo;
        } catch (IOException e) {
            LOG.error("Customer logo was not found in classpath in " + logResource, e);
            return null;
        }
    }
}