com.lion328.thaifixes.coremod.patcher.GuiNewChatBytecodePatcher.java Source code

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Here is the source code for com.lion328.thaifixes.coremod.patcher.GuiNewChatBytecodePatcher.java

Source

/*
 * Copyright (c) 2014 Waritnan Sookbuntherng
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

package com.lion328.thaifixes.coremod.patcher;

import org.objectweb.asm.ClassReader;
import org.objectweb.asm.ClassWriter;
import org.objectweb.asm.Opcodes;
import org.objectweb.asm.tree.AbstractInsnNode;
import org.objectweb.asm.tree.ClassNode;
import org.objectweb.asm.tree.FieldInsnNode;
import org.objectweb.asm.tree.IntInsnNode;
import org.objectweb.asm.tree.MethodNode;
import org.objectweb.asm.tree.VarInsnNode;

import com.lion328.thaifixes.nmod.ClassMap;
import com.lion328.thaifixes.nmod.ThaiFixesConfiguration;
import com.lion328.thaifixes.nmod.ThaiFixesFontRenderer;
import com.lion328.thaifixes.nmod.ThaiFixesFontStyle;

public class GuiNewChatBytecodePatcher implements IBytecodePatcher {

    public static final ClassMap CLASSMAP = ClassMap.getClassMap("net.minecraft.client.gui.GuiNewChat");

    @Override
    public byte[] patchClass(byte[] source) {
        if (ThaiFixesConfiguration.getFontStyle() != ThaiFixesFontStyle.MCPX)
            return source;

        ClassReader classReader = new ClassReader(source);
        ClassNode classNode = new ClassNode();
        classReader.accept(classNode, 0);

        for (MethodNode method : classNode.methods) {
            if (method.name.equals(CLASSMAP.getMethod("drawChat")) && method.desc.equals("(I)V")) {
                AbstractInsnNode currentNode = null;
                for (int i = 0; i < method.instructions.size(); i++) {
                    currentNode = method.instructions.get(i);
                    if (currentNode.getOpcode() == Opcodes.BIPUSH) {
                        if (method.instructions.get(i + 1).getOpcode() == Opcodes.IMUL)
                            method.instructions.set(currentNode,
                                    new VarInsnNode(Opcodes.BIPUSH, ThaiFixesFontRenderer.MCPX_CHATBLOCK_HEIGHT));
                        else if (method.instructions.get(i + 1).getOpcode() == Opcodes.ISUB
                                && method.instructions.get(i - 1).getOpcode() == Opcodes.ILOAD) {
                            IntInsnNode node = (IntInsnNode) currentNode;
                            if (node.operand == 9)
                                method.instructions.set(currentNode, new VarInsnNode(Opcodes.BIPUSH,
                                        ThaiFixesFontRenderer.MCPX_CHATBLOCK_HEIGHT));
                            else if (node.operand == 8)
                                method.instructions.set(currentNode, new VarInsnNode(Opcodes.BIPUSH,
                                        ThaiFixesFontRenderer.MCPX_CHATBLOCK_TEXT_YPOS));
                        }
                    }
                }
            } else if (method.name.equals(CLASSMAP.getMethod("func_146236_a"))
                    && method.desc.equals("(II)L" + ClassMap.getClassMap("net.minecraft.util.IChatComponent")
                            .getClassInfo().getProductionClassName().replace('.', '/') + ";")) {
                for (int i = 0; i < method.instructions.size(); i++) {
                    if (method.instructions.get(i).getOpcode() == Opcodes.GETFIELD) {
                        FieldInsnNode node = (FieldInsnNode) method.instructions.get(i);
                        if (node.owner.equals(ClassMap.getClassMap("net.minecraft.client.gui.FontRenderer")
                                .getClassInfo().getProductionClassName().replace('.', '/'))
                                && node.name.equals(ClassMap.getClassMap("net.minecraft.client.gui.FontRenderer")
                                        .getField("FONT_HEIGHT"))) {
                            method.instructions.set(node,
                                    new VarInsnNode(Opcodes.BIPUSH, ThaiFixesFontRenderer.MCPX_CHATBLOCK_HEIGHT));
                            method.instructions.remove(method.instructions.get(i - 1)); // GETFIELD Minecraft.mc
                            method.instructions.remove(method.instructions.get(i - 2)); // GETFIELD GuiNewChat.mc
                            method.instructions.remove(method.instructions.get(i - 3)); // ALOAD 0
                        }
                    }
                }
            }
        }

        ClassWriter writer = new ClassWriter(ClassWriter.COMPUTE_MAXS);
        classNode.accept(writer);
        return writer.toByteArray();
    }

    @Override
    public ClassMap getClassMap() {
        return CLASSMAP;
    }

}