/*
 * Copyright (C) 2025 dwlr <dweller@cabin.digital>
 *
 * BSD 3-Clause License (BSD-3-Clause)
 * See LICENSE for details
 */


#define _DEFAULT_SOURCE
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <assert.h>
#include <time.h>
#include <stdarg.h>

#include <endian.h>

#include "bits.c"
#include "log.c"

#include "chip8.c"
#include "meta/disasm.c"
#include "meta/exec.c"


int main(int argc, char** argv)
{
    u64   sz = 0;
    FILE*  f = NULL;
    chip8 c8 = {0};

    srand(time(NULL));

    c8_reset(&c8);

    if(argc > 1)
    {
        u64 got = 0;

        f = fopen(argv[1], "r");
        if(!f) return 1;

        fseek(f, 0, SEEK_END);
        sz = (u64)ftell(f);
        rewind(f);

        if(sz >= (sizeof(c8.RAM) - 512)) return 2;

        got = fread(c8.RAM + C8_RESET_VECTOR, 1, sz, f);
        if(got != sz) return 3;

        fclose(f);
    }
    else
    {
        c8.RAM[C8_RESET_VECTOR + iota] = 0x60;
        c8.RAM[C8_RESET_VECTOR + iota] = 0x04;

        c8.RAM[C8_RESET_VECTOR + iota] = 0x61;
        c8.RAM[C8_RESET_VECTOR + iota] = 0x03;

        c8.RAM[C8_RESET_VECTOR + iota] = 0x72;
        c8.RAM[C8_RESET_VECTOR + iota] = 0x01;

        c8.RAM[C8_RESET_VECTOR + iota] = 0x80;
        c8.RAM[C8_RESET_VECTOR + iota] = 0x14;

        c8.RAM[C8_RESET_VECTOR + iota] = 0x30;
        c8.RAM[C8_RESET_VECTOR + iota] = 0x10;

        c8.RAM[C8_RESET_VECTOR + iota] = 0x12;
        c8.RAM[C8_RESET_VECTOR + iota] = 0x04;

        sz = iota;
    }

    printf("Disasm:\n");
    {
        u64 i;
        char buf[512] = {0};

        for(i = 0; i < sz; i += 2)
        {
            u16 pc = C8_RESET_VECTOR + i;
            c8_disasm(c8.RAM, pc, buf);
            printf("%04X:   %s\n", pc, buf);
        }
    }

    printf("\nExec:\n");
    while(c8.running)
    {
        char buf[512] = {0};

        c8_disasm(c8.RAM, c8.pc, buf);
        printf("%04X:   %s\n", c8.pc, buf);

        c8_exec(c8.RAM, c8.pc, &c8);
        c8_dump_state(&c8, false);
    }

    return 0;
}