/*
 * Copyright (C) 2025 Danny Holman <dholman@gymli.org>
 *
 * This file is part of BoxOS, a free and open-source Unix-like operating
 * system.
 *
 * BoxOS is free software; you can redistribute it and/or modify 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.
 *
 * BoxOS is distributed in the hope 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
 * BoxOS; if not, see <https://www.gnu.org/licenses/>.
 */

#include <sys/kprintf.h>
#include <sys/serial.h>
#include <string.h>

char* convert(unsigned int num, int base) {
        static char rep[] = "0123456789ABCDEF";
        static char buffer[50];
        char *ptr;

        ptr = &buffer[49];
        *ptr = '\0';

        do {
                *--ptr = rep[num%base];
                num /= base;
        } while (num != 0);

        return ptr;
}

int vkprintf(const char *fmt, va_list args) {
        char *s;
        int i;

        char buffer[4096];
        memset(buffer, 0, 4096);
        for (size_t n = 0; n < strlen(fmt); n++) {
                if (fmt[n] != '%') {
                        buffer[strlen(buffer)] = fmt[n];
                        continue;
                } else {
                        n++;
                }

                switch (fmt[n]) {
                        case 'c':
                                i = va_arg(args, int);
                                buffer[strlen(buffer)] = i;
                                break;
                        case 's':
                                s = va_arg(args, char*);
                                strcat(buffer, s);
                                break;
                        case 'd':
                                i = va_arg(args, int);
                                if (i < 0) {
                                        i = -i;
                                        strcat(buffer, "-");
                                }
                                strcat(buffer, convert(i, 10));
                                break;
                        case 'o':
                                i = va_arg(args, unsigned int);
                                strcat(buffer, convert(i, 10));
                                break;
                        case 'x':
                                i = va_arg(args, unsigned int);
                                strcat(buffer, convert(i, 16));
                                break;
                }
        }
        //tty_write(buffer, strlen(buffer));
        memset(buffer, 0, 4096);
        return 0;
}

int kprintf(const char *fmt, ...) {
        va_list args;
        int done;

        va_start(args, fmt);
        done = vkprintf(fmt, args);
        va_end(args);

        return done;
}