Revamp update checker

src/main/java/dev/plex/util/PlexLog.java

@@ -1,6 +1,8 @@
 package dev.plex.util;
 
 import dev.plex.Plex;
+import net.kyori.adventure.text.Component;
+import net.kyori.adventure.text.format.NamedTextColor;
 import org.bukkit.Bukkit;
 import org.bukkit.ChatColor;
 
@@ -18,6 +20,11 @@ public class PlexLog
         Bukkit.getConsoleSender().sendMessage(String.format(ChatColor.YELLOW + "[Plex] " + ChatColor.GRAY + "%s", message));
     }
 
+    public static void log(Component component)
+    {
+        Bukkit.getConsoleSender().sendMessage(Component.text("[Plex] ").color(NamedTextColor.YELLOW).append(component).colorIfAbsent(NamedTextColor.GRAY));
+    }
+
     public static void error(String message, Object... strings)
     {
         for (int i = 0; i < strings.length; i++)

src/main/java/dev/plex/util/UpdateChecker.java

@@ -1,52 +1,86 @@
 package dev.plex.util;
 
+import com.google.common.base.Charsets;
+import com.google.gson.Gson;
+import com.google.gson.JsonObject;
+import com.google.gson.JsonSyntaxException;
+import dev.plex.Plex;
 import dev.plex.PlexBase;
 import java.io.BufferedReader;
 import java.io.IOException;
 import java.io.InputStreamReader;
+import java.net.HttpURLConnection;
 import java.net.URL;
-import java.net.URLConnection;
+import javax.annotation.Nonnull;
+import net.kyori.adventure.text.Component;
+import net.kyori.adventure.text.format.NamedTextColor;
 import org.bukkit.ChatColor;
 
 public class UpdateChecker extends PlexBase
 {
-    private final String currentVersion = plugin.getDescription().getVersion();
+    private static final String DOWNLOAD_PAGE = "https://ci.plex.us.org/job/Plex/";
 
-    public boolean check()
+    // Adapted from Paper
+    private int fetchDistanceFromGitHub(@Nonnull String repo, @Nonnull String branch, @Nonnull String hash)
     {
-        if (currentVersion.contains("-SNAPSHOT"))
-        {
-            PlexLog.log("Snapshot version detected, not checking for updates.");
-            return true;
-        }
         try
         {
-            String versionLink = "https://plex.us.org/updater/check/";
-            URL url = new URL(versionLink);
-            URLConnection con = url.openConnection();
-            InputStreamReader isr = new InputStreamReader(con.getInputStream());
-            BufferedReader reader = new BufferedReader(isr);
-            if (!reader.ready())
+            HttpURLConnection connection = (HttpURLConnection)new URL("https://api.github.com/repos/" + repo + "/compare/" + branch + "..." + hash).openConnection();
+            connection.connect();
+            if (connection.getResponseCode() == HttpURLConnection.HTTP_NOT_FOUND)
             {
-                return false;
+                return -2; // Unknown commit
             }
-            String newVersion = reader.readLine();
-            reader.close();
-
-            if (!newVersion.equals(currentVersion))
+            try (BufferedReader reader = new BufferedReader(new InputStreamReader(connection.getInputStream(), Charsets.UTF_8)))
             {
-                PlexLog.log(ChatColor.RED + "There is a new version of Plex available: " + newVersion);
-                return true;
+                JsonObject obj = new Gson().fromJson(reader, JsonObject.class);
+                String status = obj.get("status").getAsString();
+                return switch (status)
+                        {
+                            case "identical" -> 0;
+                            case "behind" -> obj.get("behind_by").getAsInt();
+                            default -> -1;
+                        };
             }
-            else
+            catch (JsonSyntaxException | NumberFormatException e)
             {
-                return false;
+                e.printStackTrace();
+                return -1;
             }
         }
         catch (IOException e)
         {
-            PlexLog.error("There was an error checking for updates!");
-            return false;
+            e.printStackTrace();
+            return -1;
+        }
+    }
+
+    public boolean getUpdateStatusMessage(@Nonnull String repo, @Nonnull String branch)
+    {
+        int distance;
+        distance = fetchDistanceFromGitHub(repo, branch, Plex.build.head);
+
+        switch (distance)
+        {
+            case -1 -> {
+                PlexLog.log(ChatColor.RED + "There was an error checking for updates.");
+                return false;
+            }
+            case 0 -> {
+                PlexLog.log(ChatColor.GREEN + "Your version of Plex is up to date!");
+                return true;
+            }
+            case -2 -> {
+                PlexLog.log(ChatColor.RED + "Unknown version, unable to check for updates.");
+                return false;
+            }
+            default -> {
+                PlexLog.log(Component.text("Your version of Plex is not up to date!", NamedTextColor.RED)
+                        .append(Component.newline())
+                        .append(Component.text("Download the new version at: ")
+                                .append(Component.text(DOWNLOAD_PAGE, NamedTextColor.RED))));
+                return true;
+            }
         }
     }
 }