#include <cassert>

#include "isa/checker.h"
#include "isa/isa.h"

void checker::execute() {
    bool interrupt = system.interact(ctlregs);

    if (ctlregs[HALTED])
        return;

    inst = decode(ctlregs[DATA_INSTRUCTION_FIELD_BUFFER],
                  pc,
                  mem.fetch(pc),
                  interrupt);
    auto next_pc = inst.next_pc;

    if (inst.need_indirect_load) {
        auto addr = mem.fetch(inst.init_address.value());
        if (inst.need_autoinc_store) {
            addr = (addr + 1) & 07777;
            mem.store(*inst.init_address, addr);
        }
        auto df = ctlregs[DATA_INSTRUCTION_FIELD_BUFFER] >> 3;
        inst.final_address = (df << 12) | addr;
    } else {
        assert(!inst.need_autoinc_store);
    }

    if (inst.need_exec_load)
        inst.data = mem.fetch(inst.final_address.value());

    if (inst.need_read_acc)
        inst.acc = acc;
    if (inst.need_read_link)
        inst.link = link;
    if (inst.need_read_mq)
        inst.mq = mq;
    if (inst.read_ctlreg.has_value())
        inst.ctlval = ctlregs[*inst.read_ctlreg];

    inst.execute();

    if (inst.need_write_acc)
        acc = inst.acc.value();
    if (inst.need_write_link)
        link = inst.link.value();
    if (inst.need_write_mq)
        mq = inst.mq.value();
    if (inst.write_ctlreg.has_value())
        ctlregs[*inst.write_ctlreg] = inst.ctlval.value();

    if (inst.need_exec_store)
        mem.store(inst.final_address.value(), inst.data.value());

    assert(inst.next_pc == next_pc || inst.possibly_redirects);
    pc = inst.next_pc;
}