/*
  $Id: execute.C,v 1.47 2001/02/25 17:35:49 paf Exp $
*/

#include "pa_array.h" 
#include "code.h"
#include "pa_request.h"
#include "pa_vstring.h"
#include "pa_vhash.h"
#include "pa_vunknown.h"
#include "pa_vcframe.h"
#include "pa_vmframe.h"
#include "pa_vobject.h"

#include <stdio.h>

#define PUSH(value) stack.push(value)
#define POP() static_cast<Value *>(stack.pop())
#define POP_NAME() static_cast<Value *>(stack.pop())->as_string()


char *opcode_name[]={
	"STRING",  "CODE",  "CLASS",
	"WITH_ROOT",	"WITH_SELF",	"WITH_READ",	"WITH_WRITE",
	"CONSTRUCT",
	"EXPRESSION_EVAL",	"MODIFY_EVAL",
	"WRITE",
	"GET_ELEMENT",	"GET_ELEMENT__WRITE",
	"CREATE_EWPOOL",	"REDUCE_EWPOOL",
	"CREATE_RWPOOL",	"REDUCE_RWPOOL",
	"GET_METHOD_FRAME",
	"STORE_PARAM",
	"CALL"
};

void dump(int level, const Array& ops) {
	if(0){
		int size=ops.size();
		//fprintf(stderr, "size=%d\n", size);
		for(int i=0; i<size; i++) {
			Operation op;
			op.cast=ops.quick_get(i);
			fprintf(stderr, "%8X\n", op.cast);
		}
	}

	int size=ops.size();
	//fprintf(stderr, "size=%d\n", size);
	for(int i=0; i<size; i++) {
		Operation op;
		op.cast=ops.quick_get(i);
		fprintf(stderr, "%*s%s", level*4, "", opcode_name[op.code]);

		if(op.code==OP_STRING) {
			VString *vstring=static_cast<VString *>(ops.quick_get(++i));
			fprintf(stderr, " \"%s\"", vstring->get_string()->cstr());
		}
		if(op.code==OP_CLASS) {
			VClass *vclass=static_cast<VClass *>(ops.quick_get(++i));
			fprintf(stderr, " \"%s\"", vclass->name().cstr());
		}
		fprintf(stderr, "\n");

		if(op.code==OP_CODE) {
			const Array *local_ops=reinterpret_cast<const Array *>(ops.quick_get(++i));
			dump(level+1, *local_ops);
		}
	}
}

void Request::execute(const Array& ops) {
	if(1) {
		fputs("source----------------------------", stderr);
		dump(0, ops);
		fputs("execution-------------------------", stderr);
	}

	int size=ops.size();
	//fprintf(stderr, "size=%d\n", size);
	for(int i=0; i<size; i++) {
		Operation op;
		op.cast=ops.quick_get(i);
		fprintf(stderr, "%d:%s", stack.top(), opcode_name[op.code]);

		switch(op.code) {
			// param in next instruction
		case OP_STRING:
			{
				VString *vstring=static_cast<VString *>(ops.quick_get(++i));
				fprintf(stderr, " \"%s\"", vstring->get_string()->cstr());
				PUSH(vstring);
				break;
			}
		case OP_CODE:
			{
				const Array *local_ops=reinterpret_cast<const Array *>(ops.quick_get(++i));
				fprintf(stderr, " (%d)\n", local_ops->size());
				dump(1, *local_ops);
				Junction& j=*NEW Junction(pool(), 
					*self, 0, 0,
					root,rcontext,wcontext,local_ops);
				
				Value *value=NEW VJunction(j);
				PUSH(value);
				break;
			}
		case OP_CLASS:
			{
				VClass *vclass=static_cast<VClass *>(ops.quick_get(++i));
				fprintf(stderr, " \"%s\"", vclass->name().cstr());
		        PUSH(vclass);
				break;
			}
			
			// OP_WITH
		case OP_WITH_SELF: 
			{
				PUSH(self);
				break;
			}
		case OP_WITH_ROOT: 
			{
				PUSH(root);
				break;
			}
		case OP_WITH_READ: 
			{
				PUSH(rcontext);
				break;
			}
		case OP_WITH_WRITE: 
			{
				PUSH(wcontext);
				break;
			}
			
			// ...
		case OP_CONSTRUCT:
			{
				Value *value=POP();
				String& name=POP_NAME();
				Value *ncontext=POP();
				value->set_name(name);
				ncontext->put_element(name, value);
				break;
			}
			// TODO: OP_EXPRESSION_EVAL,	OP_MODIFY_EVAL,
		case OP_WRITE:
			{
				Value *value=POP();
				wcontext->write(value);
				break;
			}
			
		case OP_GET_ELEMENT:
			{
				Value *value=get_element();
				PUSH(value);
				break;
			}

		case OP_GET_ELEMENT__WRITE:
			{
				Value *value=get_element();
				wcontext->write(value);
				break;
			}


		case OP_CREATE_EWPOOL:
			{
				PUSH(wcontext);
				wcontext=NEW WWrapper(pool(), 0 /* empty */, true /* constructing */);
				break;
			}
		case OP_REDUCE_EWPOOL:
			{
				Value *value=wcontext->result();
				wcontext=static_cast<WContext *>(POP());
				PUSH(value);
				break;
			}
			
		case OP_CREATE_RWPOOL:
			{
				Value *ncontext=POP();
				PUSH(rcontext);
				rcontext=ncontext;
				PUSH(wcontext);
				wcontext=NEW WWrapper(pool(), ncontext, false /* not constructing */);
				break;
			}
		case OP_REDUCE_RWPOOL:
			{
				String *string=wcontext->get_string();
				Value *value=NEW VString(*string);
				wcontext=static_cast<WContext *>(POP());
				rcontext=POP();
				PUSH(value);
				break;
			}

			// CALL
		case OP_GET_METHOD_FRAME:
			{
				Value *value=POP();
				// [self/class?;params;local;code/native_code](name)
				Junction *junction=value->get_junction();
				if(!junction)
					THROW(0,0,
						&value->name(),
						"type is '%s', can not call it (must be method or junction)",
							value->type()); 
				//unless(method) method=operators.get_method[...;code/native_code](name)
				VMethodFrame *frame=NEW VMethodFrame(pool(), *junction);
				PUSH(frame);
				break;
			}
		case OP_STORE_PARAM:
			{
				Value *value=POP();
				VMethodFrame *frame=static_cast<VMethodFrame *>(stack[0]);
				frame->store_param(value);
				break;
			}

		case OP_CALL:
			{
				fprintf(stderr, "->\n");
				VMethodFrame *frame=static_cast<VMethodFrame *>(POP());
				frame->fill_unspecified_params();
				PUSH(self);  
				PUSH(root);  
				PUSH(rcontext);  
				PUSH(wcontext); 
				
				VClass *called_class=frame->junction.self.get_class();
				// constructing?
				if(wcontext->constructing()) {  // yes
					// constructor call: $some(^class:method(..))
					self=NEW VObject(pool(), *called_class);
					frame->write(self);
				} else {  // no
					// context is object or class & is it my class or my parent's class?
					VClass *read_class=rcontext->get_class();
					if(read_class && read_class->is_or_derived_from(*called_class)) // yes
						self=rcontext; // class dynamic call
					else // no
						self=&frame->junction.self; // static or simple dynamic call
				}
				frame->set_self(*self);
				root=rcontext=wcontext=frame;
				{
					VAliased *aliased=reinterpret_cast<VAliased *>(self->get_aliased());
					Temp_alias temp_alias(*aliased, *frame->junction.vclass);
					execute(frame->junction.method->code);
				}
				Value *value=wcontext->result();

				wcontext=static_cast<WContext *>(POP());  
				rcontext=POP();  
				root=POP();  
				self=static_cast<VAliased *>(POP());
				wcontext->write(value);
				fprintf(stderr, "<-returned");
				break;
			}

		default:
			fprintf(stderr, "\tTODO");
			break;
		}
		fprintf(stderr, "\n");
	}
}

Value *Request::get_element() {
	String& name=POP_NAME();
	Value *ncontext=POP();
	Value *value=ncontext->get_element(name);

	if(value) {
		Junction *junction=value->get_junction();
		if(junction && junction->code) { // is it a code-junction?
			// autocalc it
			fprintf(stderr, "ja->\n");
			PUSH(self);  
			PUSH(root);  
			PUSH(rcontext);  
			PUSH(wcontext);

			// almost plain wwrapper about junction wcontext, 
			// BUT intercepts string writes
			VCodeFrame frame(pool(), *junction->wcontext);  wcontext=&frame;
			self=&junction->self;
			root=junction->root;
			rcontext=junction->rcontext;
			execute(*junction->code);
			// CodeFrame soul:
			//   string writes were intercepted
			//   returning them as the result of getting code-junction
			value=NEW VString(*frame.get_string());

			wcontext=static_cast<WContext *>(POP());  
			rcontext=POP();  
			root=POP();  
			self=static_cast<VAliased *>(POP());
			fprintf(stderr, "<-ja returned");
		}
	} else {
		value=NEW VUnknown(pool());
		value->set_name(name);
	}
	return value;
}