#include "instr.h"
#include "mem.h"

#include <stdio.h>

#include "addrs.h"

#include "instr_map.h"
#include "mem_seg.h"


uint8_t _invalid_opcode(prog_counter_t* pcounter, device_mem_t* devMem)
{
    opcode_t op = extractOpcode(devMem, *pcounter);
    printf("Invalid opcode at 0x%016X: 0x%016X\n", *pcounter, op);
    return (uint8_t)(-1);
}



void setCombinations(opcode_t base, opcode_t mask, instr_h_func* tgt, instr_h_func val) 
{
    opcode_t start_opcode = base;
    do
    {
        tgt[(start_opcode & mask) | base] = val;
        start_opcode += 1;
    } while(start_opcode < (base | mask));
    tgt[(start_opcode & mask) | base] = val;
}


void setOpcodeSizes(uint8_t* opcodeSizes)
{
    instruction_metadata_t metadataArray[] = HANDLER_REGISTERS;

    for (size_t i = 0; i < ((opcode_t)~0); i++)
    {
        opcodeSizes[i] = 0;
    }
    

    for(size_t i = 0; i < sizeof(metadataArray) / sizeof(instruction_metadata_t); i++)
    {
        opcode_t start_opcode = metadataArray[i].base;
        do
        {
            opcodeSizes[(start_opcode & metadataArray[i].argsMask) | metadataArray[i].base] = metadataArray[i].opcodeLen;
            start_opcode += 1;
        } while(start_opcode < (metadataArray[i].base | metadataArray[i].argsMask));
    }
}


instr_h_func* genInstrArray(char* errbuf) 
{

    instruction_metadata_t metadataArray[] = HANDLER_REGISTERS;

    instr_h_func* instrArray = calloc(((opcode_t)~0), sizeof(instr_h_func*));
    if (instrArray == NULL) 
    {
        sprintf(errbuf, "Unable to allocate instruction table");
        return NULL;
    }

    for (size_t i = 0; i < ((opcode_t)~0); i++)
    {
        instrArray[i] = &_invalid_opcode;
    }
    

    for(size_t i = 0; i < sizeof(metadataArray) / sizeof(instruction_metadata_t); i++)
    {
        setCombinations(metadataArray[i].base, metadataArray[i].argsMask, instrArray, metadataArray[i].h);
    }

    return instrArray;
}


opcode_t extractOpcode(device_mem_t* devMem, prog_counter_t programCounter)
{
    return ((opcode_t*)devMem->cells[MEMSEG_PS])[programCounter];
}

size_t pubExtractOpcode(device_mem_t* devMem, size_t _programCounter)
{
    prog_counter_t programCounter = (prog_counter_t)(_programCounter);
    return (size_t)(((opcode_t*)devMem->cells[MEMSEG_PS])[programCounter]);
}