Big refactor of Pandalib. More modules and better managed dependencies

Permissions/src/main/java/fr/pandacube/lib/permissions/Permissions.java

@@ -0,0 +1,107 @@
+package fr.pandacube.lib.permissions;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.UUID;
+import java.util.function.Function;
+
+import fr.pandacube.lib.db.DB;
+import fr.pandacube.lib.db.DBConnection;
+import fr.pandacube.lib.db.DBException;
+import fr.pandacube.lib.util.Log;
+
+public class Permissions {
+	
+	/* package */ static PermissionsCachedBackendReader backendReader;
+	/* package */ static PermissionsResolver resolver;
+	/* package */ static PermissionsBackendWriter backendWriter;
+	/* package */ static Function<UUID, String> playerNameGetter = UUID::toString;
+	
+	/**
+	 * Initialize the permission system.
+	 * The connection to the database needs to be initialized first, using {@link DB#init(DBConnection, String)}.
+	 */
+	public static void init(Function<UUID, String> playerNameGetter) throws DBException {
+		Permissions.playerNameGetter = playerNameGetter == null ? UUID::toString : playerNameGetter;
+		if (backendReader != null)
+			return;
+		try {
+			DB.initTable(SQLPermissions.class);
+			backendReader = new PermissionsCachedBackendReader();
+			resolver = new PermissionsResolver(backendReader);
+			backendWriter = new PermissionsBackendWriter();
+		} catch (Exception e) {
+			backendReader = null;
+			resolver = null;
+			backendWriter = null;
+			throw e;
+		}
+	}
+	
+	public static void addSpecialPermissions(SpecialPermission... specialPermissions) {
+		checkInitialized();
+		if (specialPermissions == null)
+			return;
+		resolver.specialPermissions.addAll(Arrays.asList(specialPermissions));
+	}
+
+	private static void checkInitialized() {
+		if (backendReader == null) {
+			throw new IllegalStateException("Permissions system not initialized. Check the server logs to check if there is an error during the startup, and check if the init() method is called properly.");
+		}
+	}
+	
+	public static void clearPlayerCache(UUID playerId) {
+		checkInitialized();
+		backendReader.clearPlayerCache(playerId);
+		resolver.clearPlayerFromCache(playerId);
+	}
+	
+	public static void clearCache(Runnable then) {
+		checkInitialized();
+		backendReader.clearAndResetCacheAsync(() -> {
+			resolver.clearCache();
+			if (then != null)
+				then.run();
+		});
+	}
+	
+	
+	public static PermPlayer getPlayer(UUID playerId) {
+		checkInitialized();
+		return new PermPlayer(playerId);
+	}
+	
+	public static void precachePlayerAsync(UUID playerId) {
+		checkInitialized();
+		Thread t = new Thread(() -> {
+			try {
+				backendReader.getCachedPlayer(playerId);
+			} catch (RuntimeException e) {
+				Log.warning("Can’t init player cache asynchronously: " + e.getMessage());
+			}
+		}, "Async permissions player cache loader");
+		t.setDaemon(true);
+		t.start();
+	}
+	
+	public static PermGroup getGroup(String name) {
+		checkInitialized();
+		return new PermGroup(name);
+	}
+	
+	public static List<PermGroup> getGroups() {
+		checkInitialized();
+		return PermGroup.fromCachedGroups(backendReader.getGroups());
+	}
+	
+	public static List<PermGroup> getDefaultGroups() {
+		checkInitialized();
+		return PermGroup.fromCachedGroups(backendReader.getDefaultGroups());
+	}
+	
+	public static List<String> getFullPermissionsList() {
+		return backendReader.getFullPermissionsList();
+	}
+	
+}