/*
    * Copyright (c) 2023. Roland T. Lichti, Kaiserpfalz EDV-Service.
    *
    * This program is free software: you can redistribute it and/or modify
    * it under the terms of the GNU General Public License as published by
    * the Free Software Foundation, either version 3 of the License, or
    * (at your option) any later version.
    *
    * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with this program.  If not, see <https://www.gnu.org/licenses/>.
   */
  
  /*
   * Libravatar -- Java Library for retrieving libravatars.
   *
   * The code in this package is taken from {@linkplain https://github.com/alessandroleite/libravatar-j}.
   *
   * It is licensed under a MIT license by Alessandro Leite.
   */
  package de.kaiserpfalzedv.commons.core.libravatar;
  
  import java.io.IOException;
  import java.io.InputStream;
  import java.net.URI;
  import java.nio.charset.Charset;
  import java.util.Locale;
  
  import org.apache.commons.codec.digest.DigestUtils;
  import org.apache.commons.io.IOUtils;
  
  import de.kaiserpfalzedv.commons.api.libravatar.Avatar;
  import de.kaiserpfalzedv.commons.api.libravatar.AvatarException;
  import de.kaiserpfalzedv.commons.api.libravatar.AvatarOptions;
  import de.kaiserpfalzedv.commons.api.libravatar.LibravatarDefaultImage;
  import jakarta.inject.Inject;
  import lombok.EqualsAndHashCode;
  import lombok.Getter;
  import lombok.RequiredArgsConstructor;
  import lombok.ToString;
  import lombok.experimental.Accessors;
  import lombok.extern.slf4j.Slf4j;
  
  @RequiredArgsConstructor(onConstructor = @__(@Inject))
  @ToString(onlyExplicitlyIncluded = true)
  @EqualsAndHashCode(onlyExplicitlyIncluded = true)
  @Accessors(chain = true, fluent = false)
  @Slf4j
  public class AvatarImpl implements Avatar {
      @ToString.Include
      @EqualsAndHashCode.Include
      @Getter
      private final String email;
  
      @Override
      public byte[] download(final de.kaiserpfalzedv.commons.api.libravatar.AvatarOptions options) {
          try (InputStream is = URI.create(this.buildUrl(options)).toURL().openStream()) {
              return IOUtils.toByteArray(is);
          } catch (final IOException e) {
              throw new AvatarException(e);
          }
      }
  
      @Override
      public String buildUrl(final AvatarOptions options) {
          log.debug("avatar build. https={}, sha256={}, size={}",
                  options.useHttps(), options.useSHA256(), options.imageSize());
  
          final StringBuilder sb = new StringBuilder(
                  options.useHttps() ? options.secureBaseUri()
                          : options.baseUri());
  
          sb.append(
                  options.useSHA256() ? DigestUtils.sha256Hex(this.email.toLowerCase(Locale.getDefault()).getBytes(Charset.defaultCharset()))
                          : DigestUtils.md5Hex(this.email.toLowerCase(Locale.getDefault()).getBytes(Charset.defaultCharset())));
  
          sb.append("?s=").append(options.imageSize());
  
          sb.append(
                  options.defaultImage() != LibravatarDefaultImage.DEFAULT ? "&d=" + options.defaultImage().getCode()
                          : "");
  
          return sb.toString();
      }
  }