#include "if.h"
#include "accessor.h"
#include "instrDTO.h"
#include "response.h"
#include "stage.h"

IF::IF(Stage *stage) : Stage(stage) { this->id = FETCH; }

Response IF::advance(InstrDTO &next_instr, Response p)
{
	this->advance_helper();
	if (this->status == OK && p == OK) {
		// mutual consent
		++this->pc;
		this->curr_instr->set_time_of(this->id, this->clock_cycle);
		next_instr = *this->curr_instr;
		curr_instr = nullptr;
	}
	return this->status;
}

void IF::advance_helper()
{
	Response r;
	signed int bits;

	if (this->curr_instr == nullptr) {
		r = this->storage->read_word(this->id, this->pc, bits);
		if (r == OK) {
			this->status = r;
			this->curr_instr = std::make_unique<InstrDTO>();
			this->curr_instr->set_instr_bits(bits);
		} else
			this->status = STALLED;
	}
}