/*************************************************************************/
/*  test_shader_lang.cpp                                                 */
/*************************************************************************/
/*                       This file is part of:                           */
/*                           GODOT ENGINE                                */
/*                    http://www.godotengine.org                         */
/*************************************************************************/
/* Copyright (c) 2007-2016 Juan Linietsky, Ariel Manzur.                 */
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/* 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    */
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/* The above copyright notice and this permission notice shall be        */
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/*                                                                       */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
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/*************************************************************************/
#include "test_shader_lang.h"


#include "os/main_loop.h"
#include "os/os.h"
#include "os/file_access.h"

#include "scene/gui/control.h"
#include "scene/gui/text_edit.h"
#include "print_string.h"
#include "servers/visual/shader_language.h"
#include "drivers/gles2/shader_compiler_gles2.h"


typedef ShaderLanguage SL;

namespace TestShaderLang {


static String _mktab(int p_level) {

	String tb;
	for(int i=0;i<p_level;i++) {
		tb+="\t";
	}

	return tb;
}

static String _typestr(SL::DataType p_type) {

	switch(p_type) {

		case SL::TYPE_VOID: return "void";
		case SL::TYPE_BOOL: return "bool";
		case SL::TYPE_FLOAT: return "float";
		case SL::TYPE_VEC2: return "vec2";
		case SL::TYPE_VEC3: return "vec3";
		case SL::TYPE_VEC4: return "vec4";
		case SL::TYPE_MAT3: return "mat3";
		case SL::TYPE_MAT4: return "mat4";
		case SL::TYPE_TEXTURE: return "texture";
		case SL::TYPE_CUBEMAP: return "cubemap";
		default: {}
	}

	return "";
}

static String _opstr(SL::Operator p_op) {

	switch(p_op) {
		case SL::OP_ASSIGN: return "=";
		case SL::OP_ADD: return "+";
		case SL::OP_SUB: return "-";
		case SL::OP_MUL: return "*";
		case SL::OP_DIV: return "/";
		case SL::OP_ASSIGN_ADD: return "+=";
		case SL::OP_ASSIGN_SUB: return "-=";
		case SL::OP_ASSIGN_MUL: return "*=";
		case SL::OP_ASSIGN_DIV: return "/=";
		case SL::OP_NEG: return "-";
		case SL::OP_NOT: return "!";
		case SL::OP_CMP_EQ: return "==";
		case SL::OP_CMP_NEQ: return "!=";
		case SL::OP_CMP_LEQ: return "<=";
		case SL::OP_CMP_GEQ: return ">=";
		case SL::OP_CMP_LESS: return "<";
		case SL::OP_CMP_GREATER: return ">";
		case SL::OP_CMP_OR: return "||";
		case SL::OP_CMP_AND: return "&&";
		default: return "";
	}

	return "";
}

static String dump_node_code(SL::Node *p_node,int p_level) {

	String code;

	switch(p_node->type) {

		case SL::Node::TYPE_PROGRAM: {

			SL::ProgramNode *pnode=(SL::ProgramNode*)p_node;

			for(Map<StringName,SL::Uniform>::Element *E=pnode->uniforms.front();E;E=E->next()) {

				String ucode="uniform ";
				ucode+=_typestr(E->get().type)+"="+String(E->get().default_value)+"\n";
				code+=ucode;

			}

			for(int i=0;i<pnode->functions.size();i++) {

				SL::FunctionNode *fnode=pnode->functions[i].function;

				String header;
				header=_typestr(fnode->return_type)+" "+fnode->name+"(";
				for(int i=0;i<fnode->arguments.size();i++) {

					if (i>0)
						header+=", ";
					header+=_typestr(fnode->arguments[i].type)+" "+fnode->arguments[i].name;
				}

				header+=") {\n";
				code+=header;
				code+=dump_node_code(fnode->body,p_level+1);
				code+="}\n";
			}

			code+=dump_node_code(pnode->body,p_level);
		} break;
		case SL::Node::TYPE_FUNCTION: {

		} break;
		case SL::Node::TYPE_BLOCK: {
			SL::BlockNode *bnode=(SL::BlockNode*)p_node;

			//variables
			for(Map<StringName,SL::DataType>::Element *E=bnode->variables.front();E;E=E->next()) {

				code+=_mktab(p_level)+_typestr(E->value())+" "+E->key()+";\n";
			}

			for(int i=0;i<bnode->statements.size();i++) {

				code+=_mktab(p_level)+dump_node_code(bnode->statements[i],p_level)+";\n";
			}


		} break;
		case SL::Node::TYPE_VARIABLE: {
			SL::VariableNode *vnode=(SL::VariableNode*)p_node;
			code=vnode->name;

		} break;
		case SL::Node::TYPE_CONSTANT: {
			SL::ConstantNode *cnode=(SL::ConstantNode*)p_node;
			switch(cnode->datatype) {


				case SL::TYPE_BOOL: code=cnode->value.operator bool()?"true":"false"; break;
				case SL::TYPE_FLOAT: code=cnode->value; break;
				case SL::TYPE_VEC2: { Vector2 v = cnode->value; code="vec2("+rtos(v.x)+", "+rtos(v.y)+")"; } break;
				case SL::TYPE_VEC3: { Vector3 v = cnode->value; code="vec3("+rtos(v.x)+", "+rtos(v.y)+", "+rtos(v.z)+")"; } break;
				case SL::TYPE_VEC4: { Plane v = cnode->value; code="vec4("+rtos(v.normal.x)+", "+rtos(v.normal.y)+", "+rtos(v.normal.z)+", "+rtos(v.d)+")"; } break;
				case SL::TYPE_MAT3: { Matrix3 x = cnode->value; code="mat3( vec3("+rtos(x.get_axis(0).x)+", "+rtos(x.get_axis(0).y)+", "+rtos(x.get_axis(0).z)+"), vec3("+rtos(x.get_axis(1).x)+", "+rtos(x.get_axis(1).y)+", "+rtos(x.get_axis(1).z)+"), vec3("+rtos(x.get_axis(2).x)+", "+rtos(x.get_axis(2).y)+", "+rtos(x.get_axis(2).z)+"))"; } break;
				case SL::TYPE_MAT4: { Transform x = cnode->value; code="mat4( vec3("+rtos(x.basis.get_axis(0).x)+", "+rtos(x.basis.get_axis(0).y)+", "+rtos(x.basis.get_axis(0).z)+"), vec3("+rtos(x.basis.get_axis(1).x)+", "+rtos(x.basis.get_axis(1).y)+", "+rtos(x.basis.get_axis(1).z)+"), vec3("+rtos(x.basis.get_axis(2).x)+", "+rtos(x.basis.get_axis(2).y)+", "+rtos(x.basis.get_axis(2).z)+"), vec3("+rtos(x.origin.x)+", "+rtos(x.origin.y)+", "+rtos(x.origin.z)+"))"; } break;
				default: code="<error: "+Variant::get_type_name(cnode->value.get_type())+" ("+itos(cnode->datatype)+">";
			}

		} break;
		case SL::Node::TYPE_OPERATOR: {
			SL::OperatorNode *onode=(SL::OperatorNode*)p_node;


			switch(onode->op) {

				case SL::OP_ASSIGN:
				case SL::OP_ASSIGN_ADD:
				case SL::OP_ASSIGN_SUB:
				case SL::OP_ASSIGN_MUL:
				case SL::OP_ASSIGN_DIV:
					code=dump_node_code(onode->arguments[0],p_level)+_opstr(onode->op)+dump_node_code(onode->arguments[1],p_level);
					break;

				case SL::OP_ADD:
				case SL::OP_SUB:
				case SL::OP_MUL:
				case SL::OP_DIV:
				case SL::OP_CMP_EQ:
				case SL::OP_CMP_NEQ:
				case SL::OP_CMP_LEQ:
				case SL::OP_CMP_GEQ:
				case SL::OP_CMP_LESS:
				case SL::OP_CMP_GREATER:
				case SL::OP_CMP_OR:
				case SL::OP_CMP_AND:

					code="("+dump_node_code(onode->arguments[0],p_level)+_opstr(onode->op)+dump_node_code(onode->arguments[1],p_level)+")";
					break;
				case SL::OP_NEG:
				case SL::OP_NOT:
					code=_opstr(onode->op)+dump_node_code(onode->arguments[0],p_level);
					break;
				case SL::OP_CALL:
				case SL::OP_CONSTRUCT:
					code=dump_node_code(onode->arguments[0],p_level)+"(";
					for(int i=1;i<onode->arguments.size();i++) {
						if (i>1)
							code+=", ";
						code+=dump_node_code(onode->arguments[i],p_level);
					}
					code+=")";
					break;
				default: {}
			}

		} break;
		case SL::Node::TYPE_CONTROL_FLOW: {
			SL::ControlFlowNode *cfnode=(SL::ControlFlowNode*)p_node;
			if (cfnode->flow_op==SL::FLOW_OP_IF) {

				code+="if ("+dump_node_code(cfnode->statements[0],p_level)+") {\n";
				code+=dump_node_code(cfnode->statements[1],p_level+1);
				if (cfnode->statements.size()==3) {

					code+="} else {\n";
					code+=dump_node_code(cfnode->statements[2],p_level+1);
				}

				code+="}\n";

			} else if (cfnode->flow_op==SL::FLOW_OP_RETURN) {

				if (cfnode->statements.size()) {
					code="return "+dump_node_code(cfnode->statements[0],p_level);
				} else {
					code="return";
				}
			}

		} break;
		case SL::Node::TYPE_MEMBER: {
			SL::MemberNode *mnode=(SL::MemberNode*)p_node;
			code=dump_node_code(mnode->owner,p_level)+"."+mnode->name;

		} break;
	}

	return code;

}

static Error recreate_code(void *p_str,SL::ProgramNode *p_program) {

	print_line("recr");
	String *str=(String*)p_str;

	*str=dump_node_code(p_program,0);

	return OK;


}


MainLoop* test() {

	List<String> cmdlargs = OS::get_singleton()->get_cmdline_args();

	if (cmdlargs.empty()) {
		//try editor!
		return NULL;
	}

	String test = cmdlargs.back()->get();

	FileAccess *fa = FileAccess::open(test,FileAccess::READ);

	if (!fa) {
		ERR_FAIL_V(NULL);
	}

	String code;

	while(true) {
		CharType c = fa->get_8();
		if (fa->eof_reached())
			break;
		code+=c;
	}

	int errline;
	int errcol;
	String error;
	print_line(SL::lex_debug(code));
	Error err = SL::compile(code,ShaderLanguage::SHADER_MATERIAL_FRAGMENT,NULL,NULL,&error,&errline,&errcol);

	if (err) {

		print_line("Error: "+itos(errline)+":"+itos(errcol)+" "+error);
		return NULL;
	}

	print_line("Compile OK! - pretty printing");

	String rcode;
	err = SL::compile(code,ShaderLanguage::SHADER_MATERIAL_FRAGMENT,recreate_code,&rcode,&error,&errline,&errcol);

	if (!err) {
		print_line(rcode);
	}

	ShaderCompilerGLES2 comp;
	String codeline,globalsline;
	SL::VarInfo vi;
	vi.name="mongs";
	vi.type=SL::TYPE_VEC3;


	ShaderCompilerGLES2::Flags fl;
	comp.compile(code,ShaderLanguage::SHADER_MATERIAL_FRAGMENT,codeline,globalsline,fl);

	return NULL;
}

}