#1015 Implement lazy replace of tags for welcome message

- Check which tags are used when loading the welcome message and only apply their replacements afterwards
- Moves AuthMe#replaceAllInfo to a more appropriate place
- Avoid fetching data again for each line

src/main/java/fr/xephi/authme/settings/Settings.java

@@ -19,7 +19,6 @@ import static fr.xephi.authme.util.FileUtils.copyFileFromResource;
 public class Settings extends SettingsManager {
 
     private final File pluginFolder;
-    private String[] welcomeMessage;
     private String passwordEmailMessage;
     private String recoveryCodeEmailMessage;
 
@@ -56,19 +55,9 @@ public class Settings extends SettingsManager {
         return recoveryCodeEmailMessage;
     }
 
-    /**
-     * Return the lines to output after an in-game registration.
-     *
-     * @return The welcome message
-     */
-    public String[] getWelcomeMessage() {
-        return welcomeMessage;
-    }
-
     private void loadSettingsFromFiles() {
         passwordEmailMessage = readFile("email.html");
         recoveryCodeEmailMessage = readFile("recovery_code_email.html");
-        welcomeMessage = readFile("welcome.txt").split("\\n");
     }
 
     @Override

src/main/java/fr/xephi/authme/settings/WelcomeMessageConfiguration.java

@@ -0,0 +1,143 @@
+package fr.xephi.authme.settings;
+
+import fr.xephi.authme.ConsoleLogger;
+import fr.xephi.authme.data.auth.PlayerCache;
+import fr.xephi.authme.initialization.DataFolder;
+import fr.xephi.authme.initialization.Reloadable;
+import fr.xephi.authme.service.BukkitService;
+import fr.xephi.authme.service.GeoIpService;
+import fr.xephi.authme.util.PlayerUtils;
+import fr.xephi.authme.util.lazytags.Tag;
+import org.bukkit.Server;
+import org.bukkit.entity.Player;
+
+import javax.annotation.PostConstruct;
+import javax.inject.Inject;
+import java.io.File;
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.stream.Collectors;
+
+import static fr.xephi.authme.util.FileUtils.copyFileFromResource;
+
+/**
+ * Configuration for the welcome message (welcome.txt).
+ */
+public class WelcomeMessageConfiguration implements Reloadable {
+
+    @DataFolder
+    @Inject
+    private File pluginFolder;
+
+    @Inject
+    private Server server;
+
+    @Inject
+    private GeoIpService geoIpService;
+
+    @Inject
+    private BukkitService bukkitService;
+
+    @Inject
+    private PlayerCache playerCache;
+
+    /** List of all supported tags for the welcome message. */
+    private final List<Tag> availableTags = Arrays.asList(
+        new Tag("&",            () -> "\u00a7"),
+        new Tag("{PLAYER}",     pl -> pl.getName()),
+        new Tag("{ONLINE}",     () -> Integer.toString(bukkitService.getOnlinePlayers().size())),
+        new Tag("{MAXPLAYERS}", () -> Integer.toString(server.getMaxPlayers())),
+        new Tag("{IP}",         pl -> PlayerUtils.getPlayerIp(pl)),
+        new Tag("{LOGINS}",     () -> Integer.toString(playerCache.getLogged())),
+        new Tag("{WORLD}",      pl -> pl.getWorld().getName()),
+        new Tag("{SERVER}",     () -> server.getServerName()),
+        new Tag("{VERSION}",    () -> server.getBukkitVersion()),
+        new Tag("{COUNTRY}",    pl -> geoIpService.getCountryName(PlayerUtils.getPlayerIp(pl))));
+
+    /** Welcome message, by lines. */
+    private List<String> welcomeMessage;
+    /** Tags used in the welcome message. */
+    private List<Tag> usedTags;
+
+    @PostConstruct
+    @Override
+    public void reload() {
+        welcomeMessage = readWelcomeFile();
+        usedTags = determineUsedTags(welcomeMessage);
+    }
+
+    /**
+     * Returns the welcome message for the given player.
+     *
+     * @param player the player for whom the welcome message should be prepared
+     * @return the welcome message
+     */
+    public List<String> getWelcomeMessage(Player player) {
+        // Note ljacqu 20170121: Using a Map might seem more natural here but we avoid doing so for performance
+        // Although the performance gain here is probably minimal...
+        List<TagValue> tagValues = new LinkedList<>();
+        for (Tag tag : usedTags) {
+            tagValues.add(new TagValue(tag.getName(), tag.getValue(player)));
+        }
+
+        List<String> adaptedMessages = new LinkedList<>();
+        for (String line : welcomeMessage) {
+            String adaptedLine = line;
+            for (TagValue tagValue : tagValues) {
+                adaptedLine = adaptedLine.replace(tagValue.tag, tagValue.value);
+            }
+            adaptedMessages.add(adaptedLine);
+        }
+        return adaptedMessages;
+    }
+
+    /**
+     * @return the lines of the welcome message file
+     */
+    private List<String> readWelcomeFile() {
+        File welcomeFile = new File(pluginFolder, "welcome.txt");
+        if (copyFileFromResource(welcomeFile, "welcome.txt")) {
+            try {
+                return Files.readAllLines(welcomeFile.toPath(), StandardCharsets.UTF_8);
+            } catch (IOException e) {
+                ConsoleLogger.logException("Failed to read welcome.txt file:", e);
+            }
+        } else {
+            ConsoleLogger.warning("Failed to copy welcome.txt from JAR");
+        }
+        return Collections.emptyList();
+    }
+
+    /**
+     * Determines which tags are used in the message.
+     *
+     * @param welcomeMessage the lines of the welcome message
+     * @return the tags
+     */
+    private List<Tag> determineUsedTags(List<String> welcomeMessage) {
+        return availableTags.stream()
+            .filter(tag -> welcomeMessage.stream().anyMatch(msg -> msg.contains(tag.getName())))
+            .collect(Collectors.toList());
+    }
+
+    private static final class TagValue {
+
+        private final String tag;
+        private final String value;
+
+        TagValue(String tag, String value) {
+            this.tag = tag;
+            this.value = value;
+        }
+
+        @Override
+        public String toString() {
+            return "TagValue[tag='" + tag + "', value='" + value + "']";
+        }
+    }
+}