package de.twomartens.template.controller;

import java.io.FileNotFoundException;
import java.io.InputStream;
import java.net.InetAddress;
import java.net.URL;
import java.net.UnknownHostException;
import java.nio.charset.StandardCharsets;
import java.nio.file.Paths;
import java.util.Collection;
import java.util.List;
import java.util.Optional;
import java.util.jar.JarFile;
import java.util.zip.ZipEntry;
import lombok.RequiredArgsConstructor;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.RequestHeader;
import org.springframework.web.bind.annotation.RequestMapping;

/**
 * used to show version and title information on html pages
 */
@Slf4j
@Controller
@RequiredArgsConstructor
@RequestMapping(value = "/vorlage")
public class VersionHtmlController {

  @GetMapping(path = "/html/version.html")
  public String version() {
    return "version";
  }

  @ControllerAdvice
  public static class VersionControllerAdvice {

    @ModelAttribute("version")
    public String getApplicationVersion() {
      return getTitle() + " " + getVersion();
    }

    @ModelAttribute("footerString")
    public String getApplicationVersion(@RequestHeader("host") String hostName) {
      return getTitle() + " " + getVersion() + " - " + hostName;
    }

    private String getTitle() {
      return Optional.ofNullable(VersionControllerAdvice.class.getPackage().getImplementationTitle())
          .filter(s -> !s.isBlank())
          .orElse("application");
    }

    public String getVersion() {
      return Optional.ofNullable(VersionControllerAdvice.class.getPackage().getImplementationVersion())
          .filter(s -> !s.isBlank())
          .orElse("DEVELOPER");
    }

    @ModelAttribute("hostname")
    public String getHostname() {
      try {
        return InetAddress.getLocalHost().getHostName();
      } catch (UnknownHostException e) {
        log.warn(e.toString(), e);
      }
      return "";
    }

    @ModelAttribute("manifest")
    private Collection<String> getManifest() {
      try {
        URL location = getClass().getProtectionDomain().getCodeSource().getLocation();
        String jarFileName = Paths.get(location.toURI()).toString();
        try (JarFile jarFile = new JarFile(jarFileName)) {
          ZipEntry entry = jarFile.getEntry(JarFile.MANIFEST_NAME);
          try (InputStream in = jarFile.getInputStream(entry)) {
            return new String(in.readAllBytes(), StandardCharsets.UTF_8).lines().toList();
          }
        }
      } catch (FileNotFoundException ignored) {
        // do nothing if manifest file is not available
      } catch (Exception e) {
        log.info(e.toString(), e);
      }
      return List.of(getTitle() + " " + getVersion());
    }

  }


}