Addition of functionalities about redstone (#3091)

* ExprBlockPower - Expression for recovering redstone power from a block.

* ExprRedstoneBlockPower - Code review changes

* CondIsBlockRedstonePowered - Condition to check if a block is powered by redstone

* ExprRedstoneBlockPower - Code review change

src/main/java/ch/njol/skript/conditions/CondIsBlockRedstonePowered.java

@@ -0,0 +1,49 @@
+/**
+ *   This file is part of Skript.
+ *
+ *  Skript 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.
+ *
+ *  Skript 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 Skript.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ *
+ * Copyright 2011-2017 Peter Güttinger and contributors
+ */
+package ch.njol.skript.conditions;
+
+import org.bukkit.block.Block;
+import ch.njol.skript.conditions.base.PropertyCondition;
+import ch.njol.skript.doc.Description;
+import ch.njol.skript.doc.Examples;
+import ch.njol.skript.doc.Name;
+import ch.njol.skript.doc.Since;
+
+@Name("Is Block Redstone Powered")
+@Description("Checks if a block is powered by redstone")
+@Examples({"if clicked block is redstone powered:",
+	"\tsend \"This block is well-powered by redstone!\""})
+@Since("INSERT VERSION")
+public class CondIsBlockRedstonePowered extends PropertyCondition<Block> {
+
+	static {
+		register(CondIsBlockRedstonePowered.class, "redstone powered", "blocks");
+	}
+
+	@Override
+	public boolean check(Block b) {
+		return b.isBlockPowered();
+	}
+
+	@Override
+	protected String getPropertyName() {
+		return "redstone powered";
+	}
+}

src/main/java/ch/njol/skript/expressions/ExprRedstoneBlockPower.java

@@ -0,0 +1,55 @@
+/**
+ *   This file is part of Skript.
+ *
+ *  Skript 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.
+ *
+ *  Skript 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 Skript.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ *
+ * Copyright 2011-2017 Peter Güttinger and contributors
+ */
+package ch.njol.skript.expressions;
+
+import org.bukkit.block.Block;
+import ch.njol.skript.doc.Description;
+import ch.njol.skript.doc.Examples;
+import ch.njol.skript.doc.Name;
+import ch.njol.skript.doc.Since;
+import ch.njol.skript.expressions.base.SimplePropertyExpression;
+
+@Name("Redstone Block Power")
+@Description("Power of a redstone block")
+@Examples({"if redstone power of targeted block is 15:",
+	"\tsend \"This block is very powerful!\""})
+@Since("INSERT VERSION")
+public class ExprRedstoneBlockPower extends SimplePropertyExpression<Block, Number> {
+
+	static {
+		register(ExprRedstoneBlockPower.class, Number.class, "redstone power", "blocks");
+	}
+
+	@Override
+	public Number convert(Block b) {
+		return b.getBlockPower();
+	}
+
+	@Override
+	public Class<? extends Number> getReturnType() {
+		return Number.class;
+	}
+
+	@Override
+	protected String getPropertyName() {
+		return "redstone power";
+	}
+
+}