/*
 * ntsys.h
 * 
 * Copyright 2026 
 * 
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
 * MA 02110-1301, USA.
 * 
 * 
 */

#if (!defined(__LIB_ntsys_H_))
#define __LIB_ntsys_H_

#define NTSYS_VERSION "1.0"

#define NAME_OF_32_BITS_TYPE unsigned int
#define NAME_OF_64_BITS_TYPE unsigned long int
#define NAME_OF_16_BITS_TYPE unsigned short int

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "ntfiles.h"

#if (!defined(EXIT_SUCCESS)) 
#define EXIT_SUCCESS 0
#endif

#if (!defined(EXIT_FAILURE)) 
#define EXIT_FAILURE 1
#endif

static void ntsys_error(char* _err) {
    printf("\033[1mntsys: \033[91m%s\033[0m\n", _err);
}

static void __help(void) {
    puts ( 
        "BINARY Emulator V" NTSYS_VERSION                   "\n"
        "    " "VM for micron files"                        "\n"
        "Using:"                                            "\n"
        "    " "ntsys [OPTIONS...] [FILENAME]"              "\n"
        "Examples:"                                         "\n"
        "    " "ntsys --asm FILE.asm"                       "\n"
        "    " "ntsys [--asm] FILE.asm --out FILE.exe"      "\n"
        "    " "ntsys FILE.exe"                             "\n"
        "Options:"                                          "\n"
        "    " "--help / -h    - show this help"            "\n"
        "    " "--version / -v - show version"              "\n"
        "    " "--asm / -a     - compile assembler program" "\n"
        "    " "--out / -o     - set output file name"      "\0"
    );
}

static int __exe_run(__e_byte_t* memory, unsigned int memorysize, unsigned long filesize, FILE* fp) {
    return EXIT_SUCCESS;
}

int ntsys_api_call(char* filename) {

    /* File data */

    __e_image_header_t head;
    __e_byte_t head_bin[8];

    /* Parser */

    FILE* fp = fopen(filename, "r");
    if (fp == NULL) {
        ntsys_error("Cannot open file!");
        return EXIT_FAILURE;
    }
    short int res1 = ((fread(&head_bin, 1, sizeof(head_bin), fp)));
    head.e_magic[0] = head_bin[0];
    head.e_magic[1] = head_bin[1];
    head.e_magic[2] = (__e_byte_t)0;
    int __i = 1;  
    size_t i = 0;
    if (*((char *)&__i) == 1) {
        /* LITTLE ENDIAN */
        head.e_memorysize[0] = head_bin[7];
        head.e_memorysize[1] = head_bin[6];
        i = 3;
        while (1) {
            head.e_filesize[i] = head_bin[5 - i];
            if (i == 0) break;
            i --;
        }
    } else {
        /* BIG ENDIAN */
        head.e_memorysize[0] = head_bin[6];
        head.e_memorysize[1] = head_bin[7];
        while (i != 4) {
            head.e_filesize[i] = head_bin[2 + i];
            i ++;
        }
    } 
    short int res2 = (strcmp(((char*)head.e_magic), "MZ"));
    if (res1 != sizeof(head_bin) || res2 != 0) {
        ntsys_error("Header read error or digital signature is invalid!");
        return EXIT_FAILURE;
    }
    unsigned long int filesize = 0;
    switch (4) {
        case sizeof(NAME_OF_64_BITS_TYPE): filesize = *((NAME_OF_64_BITS_TYPE*)head.e_filesize); break;
        case sizeof(NAME_OF_32_BITS_TYPE): filesize = *((NAME_OF_32_BITS_TYPE*)head.e_filesize); break;
        default:
        ntsys_error("Unknown data type! You must recompile the program and specify a different type.");
        return EXIT_FAILURE;
    }
    __e_byte_t* memory = malloc(*((NAME_OF_16_BITS_TYPE*)head.e_memorysize));
    int stat = __exe_run(memory, (unsigned int)*((NAME_OF_16_BITS_TYPE*)head.e_memorysize), filesize, fp);
    fclose(fp);
    free(memory);
    return stat;
}

int ntsys_compile_asm(char* in_file, char* out_file) {
    return EXIT_SUCCESS;
}

int _lib_ntsys_main(int argc, char** argv) {
    unsigned int t = 1;
    char* filename = NULL;
    char* asm_out = "out.exe";
    char mode = 'R';
    unsigned char out = 0;
    while (t < argc) {
        char* str = argv[t];
        if (str[0] == '-') {
            unsigned char f = 0;
            if (str[1] == '-') f = 1;
            switch (str[1 + f]) {
                case 'h':
                __help();
                return EXIT_SUCCESS;
                case 'v':
                puts(NTSYS_VERSION);
                return EXIT_SUCCESS;
                case 'a':
                mode = 'A';
                break;
                case 'o':
                out = 1;
                mode = 'A';
                break;
                default:
                ntsys_error("Unknown option!");
                return EXIT_FAILURE;
            }
        } else {
            if (out) {
                asm_out = str;
                out = 0;
            } else {
                filename = str;
            }
        }
        t ++;
    }
    if (filename == NULL || out) {
        ntsys_error("Please specify the file name!");
        return EXIT_FAILURE;
    }
    if (mode == 'R') return ntsys_api_call(filename);
    return ntsys_compile_asm(filename, asm_out);
}

#endif /* __LIB_ntsys_H_ */