package shadersmodcore.transform;

import java.util.Iterator;

import org.lwjgl.opengl.GL11;
import org.objectweb.asm.ClassReader;
import org.objectweb.asm.ClassVisitor;
import org.objectweb.asm.ClassWriter;
import org.objectweb.asm.FieldVisitor;
import org.objectweb.asm.Label;
import org.objectweb.asm.MethodVisitor;
import org.objectweb.asm.Opcodes;
import static org.objectweb.asm.Opcodes.*;

import org.objectweb.asm.commons.Remapper;
import org.objectweb.asm.tree.MethodNode;


import net.minecraft.launchwrapper.IClassTransformer;

public class SMCCTRenderGlobal implements IClassTransformer {

	@Override
	public byte[] transform(String par1, String par2, byte[] par3) {
		SMCLog.fine("transforming %s %s",par1,par2);
		ClassReader cr = new ClassReader(par3);
		ClassWriter cw = new ClassWriter(cr, ClassWriter.COMPUTE_MAXS);
		CVTransform cv = new CVTransform(cw);
		cr.accept(cv,0);
		return cw.toByteArray();
	}

	private static class CVTransform extends ClassVisitor
	{
		String classname;
		public CVTransform(ClassVisitor cv)
		{
			super(Opcodes.ASM4, cv);		
		}

		@Override
		public void visit(int version, int access, String name,
				String signature, String superName, String[] interfaces) {
			classname = name;
			//SMCLog.info(" class %s",name);
			cv.visit(version, access, name, signature, superName, interfaces);
		}

		@Override
		public FieldVisitor visitField(int access, String name, String desc,
				String signature, Object value) {
			if (Names.renderGlobal_worldRenderers.name.equals(name)) {
				access = access & (~ACC_PRIVATE & ~ACC_PROTECTED) | ACC_PUBLIC;
			}
			return cv.visitField(access, name, desc, signature, value);
		}

		@Override
		public MethodVisitor visitMethod(int access, String name, String desc,
				String signature, String[] exceptions) 
		{
			//String remappedName = SMCRemap.remapper.mapMethodName(classname, name, desc);
			//SMCLog.info("  method %s.%s%s = %s",classname,name,desc,remappedName);
			if (Names.renderGlobal_renderEntities.equalsNameDesc(name, desc))
			{
				SMCLog.finer("  patch method %s.%s%s",classname,name,desc);
				return new MVrenderEntities(cv.visitMethod(access, name, desc, signature, exceptions));
			}
			else if (Names.renderGlobal_sortAndRender.equalsNameDesc(name, desc))
			{
				SMCLog.finer("  patch method %s.%s%s",classname,name,desc);
				return new MVendisTexFog(cv.visitMethod(access, name, desc, signature, exceptions));
			}
			else if (Names.renderGlobal_renderSky.equalsNameDesc(name, desc))
			{
				SMCLog.finer("  patch method %s.%s%s",classname,name,desc);
				return new MVrenderSky(cv.visitMethod(access, name, desc, signature, exceptions));
			}
			else if (Names.renderGlobal_drawBlockDamageTexture.equalsNameDesc(name, desc)
				|| name.equals("drawBlockDamageTexture") ) // Optifine
			{
				SMCLog.finer("  patch method %s.%s%s",classname,name,desc);
				return new MVdrawBlockDamageTexture(cv.visitMethod(access, name, desc, signature, exceptions));
			}
			else if (Names.renderGlobal_drawSelectionBox.equalsNameDesc(name, desc))
			{
				SMCLog.finer("  patch method %s.%s%s",classname,name,desc);
				return new MVendisTexFog(cv.visitMethod(access, name, desc, signature, exceptions));
			}
			return cv.visitMethod(access, name, desc, signature, exceptions);
		}
		
	}

	private static class MVrenderEntities extends MethodVisitor
	{
		public MVrenderEntities(MethodVisitor mv) {
			super(Opcodes.ASM4, mv);
		}
		
		int state = 0;

		@Override
		public void visitLdcInsn(Object cst) {
			if (cst instanceof String) {
				String scst = (String)cst;
				if (scst.equals("entities")) {
					state = 1;
				}
				else if (scst.equals("blockentities")) {
					state = 4;
				}
			}
			mv.visitLdcInsn(cst);
		}

		@Override
		public void visitFieldInsn(int opcode, String owner, String name,
				String desc) {
			if (state==2) {
				if (Names.renderManager_instance.equals(owner, name, desc)) {
					state = 3;
					mv.visitMethodInsn(INVOKESTATIC, "shadersmodcore/client/Shaders", "nextEntity", "()V");
				}
			}
			mv.visitFieldInsn(opcode, owner, name, desc);
		}

		@Override
		public void visitMethodInsn(int opcode, String owner, String name, String desc) {
			mv.visitMethodInsn(opcode, owner, name, desc);
			if (state == 1) {
				state = 2;
				mv.visitMethodInsn(INVOKESTATIC, "shadersmodcore/client/Shaders", "beginEntities", "()V");
				SMCLog.finest("    %s","beginEntities");
			} else if (state == 4) {
				state = 5;
				mv.visitMethodInsn(INVOKESTATIC, "shadersmodcore/client/Shaders", "endEntities", "()V");
				SMCLog.finest("    %s","endEntities");
				mv.visitMethodInsn(INVOKESTATIC, "shadersmodcore/client/Shaders", "beginBlockEntities", "()V");
				SMCLog.finest("    %s","beginTileEntities");
			} else if (state == 5) {
				if (Names.entityRenderer_disableLightmap.equals(owner, name, desc)) {
					state = 6;
					mv.visitMethodInsn(INVOKESTATIC, "shadersmodcore/client/Shaders", "endBlockEntities", "()V");
					SMCLog.finest("    %s","endTileEntities");
				}
			}
		}

	}

	/* detect glEnable or glDisable (TEXTURE_2D or FOG) */
	private static class MVendisTexFog extends MethodVisitor
	{
		public MVendisTexFog(MethodVisitor mv) {
			super(Opcodes.ASM4, mv);
		}

		int lastInt = 0;

		@Override
		public void visitIntInsn(int opcode, int operand) {
			mv.visitIntInsn(opcode, operand);
			if (opcode == SIPUSH && (operand==3553 || operand==2912)) {
				lastInt = operand;
			}
			else {
				lastInt = 0;
			}
		}

		@Override
		public void visitMethodInsn(int opcode, String owner, String name, String desc) {
			mv.visitMethodInsn(opcode, owner, name, desc);
			if (owner.equals("org/lwjgl/opengl/GL11")) {
				if (name.equals("glEnable")) {
					if (lastInt==GL11.GL_TEXTURE_2D) {
						mv.visitMethodInsn(INVOKESTATIC, "shadersmodcore/client/Shaders", "enableTexture2D", "()V");
						SMCLog.finest("    %s","enableTexture2D");
					} else if (lastInt==GL11.GL_FOG) {
						mv.visitMethodInsn(INVOKESTATIC, "shadersmodcore/client/Shaders", "enableFog", "()V");
						SMCLog.finest("    %s","enableFog");
					}
				} else if (name.equals("glDisable")) {
					if (lastInt==GL11.GL_TEXTURE_2D) {
						mv.visitMethodInsn(INVOKESTATIC, "shadersmodcore/client/Shaders", "disableTexture2D", "()V");
						SMCLog.finest("    %s","disableTexture2D");
					} else if (lastInt==GL11.GL_FOG) {
						mv.visitMethodInsn(INVOKESTATIC, "shadersmodcore/client/Shaders", "disableFog", "()V");
						SMCLog.finest("    %s","disableFog");
					}
				}
			}
			lastInt = 0;
		}
	}

	/* extends MVenableTF */
	private static class MVrenderSky extends MVendisTexFog
	{
		public MVrenderSky(MethodVisitor mv) {
			super(mv);
		}
		
		int state = 0;
		boolean detectedOptifine = false;
		
		int lastInt = 0;
		int lastVar = 0;

		@Override
		public void visitIntInsn(int opcode, int operand) {
			mv.visitIntInsn(opcode, operand);
			if (opcode == SIPUSH) {
				lastInt = operand;
			} else {
				lastInt = 0;
			}
		}

		@Override
		public void visitVarInsn(int opcode, int var) {
			mv.visitVarInsn(opcode, var);
			if (opcode == ALOAD) {
				lastVar = var;
			} else {
				lastVar = 0;
			}
		}



		@Override
		public void visitFieldInsn(int opcode, String owner, String name, String desc) {
			switch (state)
			{
			case 0:
				if (Names.vec3_xCoord.equals(owner, name)) {
					++state;
					mv.visitMethodInsn(INVOKESTATIC, "shadersmodcore/client/Shaders", "setSkyColor", "("+Names.vec3_.desc+")V");
					mv.visitVarInsn(ALOAD, lastVar);
					break;
				}
				break;
			case 1:
				if (Names.renderGlobal_glSkyList.equals(owner, name)) {
					++state;
					mv.visitMethodInsn(INVOKESTATIC, "shadersmodcore/client/Shaders", "preSkyList", "()V");
					break;
				}
				break;
			}
			mv.visitFieldInsn(opcode, owner, name, desc);
		}

		@Override
		public void visitMethodInsn(int opcode, String owner, String name, String desc) {
			//SMCLog.info("    %s.%s%s",ownerM,nameM,descM);
			switch (state) {
			case 0:
				if (owner.equals("Config") && name.equals("isSkyEnabled")) {
					detectedOptifine = true;
				}
				break;
			case 2:
				if (Names.worldClient_getRainStrength.equals(owner, name, desc)) {
					++state;
				}
				break;
			}
			//
			mv.visitMethodInsn(opcode, owner, name, desc);
			//
			if (owner.equals("org/lwjgl/opengl/GL11")) {
				if (name.equals("glEnable")) {
					if (lastInt==GL11.GL_TEXTURE_2D) {
						mv.visitMethodInsn(INVOKESTATIC, "shadersmodcore/client/Shaders", "enableTexture2D", "()V");
						SMCLog.finest("    %s","enableTexture2D");
					} else if (lastInt==GL11.GL_FOG) {
						mv.visitMethodInsn(INVOKESTATIC, "shadersmodcore/client/Shaders", "enableFog", "()V");
						SMCLog.finest("    %s","enableFog");
					}
				} else if (name.equals("glDisable")) {
					if (lastInt==GL11.GL_TEXTURE_2D) {
						mv.visitMethodInsn(INVOKESTATIC, "shadersmodcore/client/Shaders", "disableTexture2D", "()V");
						SMCLog.finest("    %s","disableTexture2D");
					} else if (lastInt==GL11.GL_FOG) {
						mv.visitMethodInsn(INVOKESTATIC, "shadersmodcore/client/Shaders", "disableFog", "()V");
						SMCLog.finest("    %s","disableFog");
					}
				} else if (name.equals("glRotatef")) {
					SMCLog.finest("    *%s %d","glRotatef",state);
					if (state == 3) {
						++state;
						mv.visitMethodInsn(INVOKESTATIC, "shadersmodcore/client/Shaders", "preCelestialRotate", "()V");
						SMCLog.finest("    %s","preCelestialRotate");
					} else if (state == 4) {
						++state;
						mv.visitMethodInsn(INVOKESTATIC, "shadersmodcore/client/Shaders", "postCelestialRotate", "()V");
						SMCLog.finest("    %s","postCelestialRotate");
					}
				}
			}
		}
	}

	private static class MVdrawBlockDamageTexture extends MethodVisitor
	{
		int state = 0;
		
		public MVdrawBlockDamageTexture(MethodVisitor mv) {
			super(Opcodes.ASM4, mv);
		}

		@Override
		public void visitIntInsn(int opcode, int operand) {
			switch(state)
			{
			case 0:
				if (opcode==SIPUSH && operand==GL11.GL_ALPHA_TEST) {
					++state;
				}
				break;
			case 2:
				if (opcode==SIPUSH && operand==GL11.GL_ALPHA_TEST) {
					++state;
					mv.visitMethodInsn(INVOKESTATIC, "shadersmodcore/client/Shaders", "endBlockDestroyProgress", "()V");
					SMCLog.finest("    %s","endBlockDestroyProgress");
				}
				break;
			}
			mv.visitIntInsn(opcode, operand);
		}

		@Override
		public void visitMethodInsn(int opcode, String owner, String name, String desc) {
			switch(state)
			{
			case 1:
				if (owner.equals("org/lwjgl/opengl/GL11") && name.equals("glEnable")) {
					++state;
					mv.visitMethodInsn(opcode, owner, name, desc);
					mv.visitMethodInsn(INVOKESTATIC, "shadersmodcore/client/Shaders", "beginBlockDestroyProgress", "()V");
					SMCLog.finest("    %s","beginBlockDestroyProgress");
					return;
				}
				break;
			}
			mv.visitMethodInsn(opcode, owner, name, desc);
		}
	}

}