#include "../include/common.h"
#include "../include/graphics.h"
#include "../include/memory.h"
#include "../include/io.h"

static char num_str_buf[BUF_SIZE];

void insert_char(char* str, int pos, char ch) {
    int i;
    for (i = strlen(str); i >= pos; i--) {
        str[i + 1] = str[i];
    }
    str[pos] = ch;
}
void delete_char(char* str, int pos) {
    int i;
    for (i = pos; i < strlen(str); i++) {
        str[i] = str[i + 1];
    }
}

void strtoupper(char* str) {
    while (*str != '\0') {
        if (*str >= 'a' && *str <= 'z') {
            *str -= 32;
        }
        str++;
    }
}

int strncmp(const char* s1, const char* s2, size_t n) {
    const unsigned char *p1 = (const unsigned char*)s1,
            *p2 = (const unsigned char*)s2;
    while (n-- > 0) {
        if (*p1 != *p2)
            return *p1 - *p2;
        if (*p1 == '\0')
            return 0;
        p1++, p2++;
    }
    return 0;
}

long int strtol(const char *str,char **endptr,int base){
    const char *s;
    unsigned long acc;
    char c;
    unsigned long cutoff;
    int neg, any, cutlim;
    s = str;
    do {
        c = *s++;
    } while (isspace((unsigned char)c));
    if (c == '-') {
        neg = 1;
        c = *s++;
    } else {
        neg = 0;
        if (c == '+')
            c = *s++;
    }
    if ((base == 0 || base == 16) &&
        c == '0' && (*s == 'x' || *s == 'X') &&
        ((s[1] >= '0' && s[1] <= '9') ||
         (s[1] >= 'A' && s[1] <= 'F') ||
         (s[1] >= 'a' && s[1] <= 'f'))) {
        c = s[1];
        s += 2;
        base = 16;
    }
    if (base == 0)
        base = c == '0' ? 8 : 10;
    acc = any = 0;
    if (base < 2 || base > 36)
        goto noconv;

    cutoff = neg ? (unsigned long)-(LONG_MIN + LONG_MAX) + LONG_MAX
                 : LONG_MAX;
    cutlim = cutoff % base;
    cutoff /= base;
    for ( ; ; c = *s++) {
        if (c >= '0' && c <= '9')
            c -= '0';
        else if (c >= 'A' && c <= 'Z')
            c -= 'A' - 10;
        else if (c >= 'a' && c <= 'z')
            c -= 'a' - 10;
        else
            break;
        if (c >= base)
            break;
        if (any < 0 || acc > cutoff || (acc == cutoff && c > cutlim))
            any = -1;
        else {
            any = 1;
            acc *= base;
            acc += c;
        }
    }
    if (any < 0) {
        acc = neg ? LONG_MIN : LONG_MAX;
    } else if (!any) {
        noconv:
    } else if (neg)
        acc = -acc;
    if (endptr != NULL)
        *endptr = (char *)(any ? s - 1 : str);
    return (acc);
}

size_t strnlen(const char *s, size_t maxlen) {
    const char *es = s;
    while (*es && maxlen) {
        es++;
        maxlen--;
    }

    return (es - s);
}

size_t strlen(const char *str) {
    size_t len = 0;
    while (str[len])
        len++;
    return len;
}

int strcmp(const char *s1, const char *s2) {
    char is_equal = 1;

    for (; (*s1 != '\0') && (*s2 != '\0'); s1++, s2++) {
        if (*s1 != *s2) {
            is_equal = 0;
            break;
        }
    }

    if (is_equal) {
        if (*s1 != '\0') {
            return 1;
        } else if (*s2 != '\0') {
            return -1;
        } else {
            return 0;
        }
    } else {
        return (int) (*s1 - *s2);
    }
}

char *strcpy(char *dest, const char *src) {
    do {
        *dest++ = *src++;
    } while (*src != 0);
    *dest = 0;
}

char *strcat(char *dest, const char *src) {
    char *temp = dest;
    while (*temp != '\0')
        temp++;
    while ((*temp++ = *src++) != '\0');
}

int isspace(int c) {
    return (c == ' ' || c == '\t' || c == '\n' || c == '\r' || c == '\f' ||
            c == '\v');
}

// isdigit
int isdigit(int c) {
    return (c >= '0' && c <= '9');
}

// isalpha
int isalpha(int c) {
    return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z');
}

// isupper
int isupper(int c) {
    return (c >= 'A' && c <= 'Z');
}

char *int32_to_str_dec(int32_t num, int flag, int width) {
    int32_t num_tmp = num;
    char *p = num_str_buf;
    char *q = NULL;
    int len = 0;
    char *str_first = NULL;
    char *str_end = NULL;
    char ch = 0;

    memset(num_str_buf, 0, sizeof(num_str_buf));

    char dic[] = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9'};

    if (num_tmp < 0) {
        *p++ = '-';
    } else if (flag & FLAG_SIGN) {
        *p++ = '+';
    } else {
        *p++ = ' ';
    }
    str_first = num_str_buf;

    if (num_tmp >= 0 && !(flag & FLAG_SIGN)) {
        str_first++;
    }

    if (num_tmp == 0) {
        *p++ = '0';
    } else {
        if (num_tmp < 0)
            num_tmp = -num_tmp;

        while (num_tmp) {
            *p++ = dic[num_tmp % 10];
            num_tmp /= 10;
        }
    }
    *p = '\0';

    str_end = p;
    len = str_end - str_first;

    q = num_str_buf + 1;
    p--;
    while (q < p) {
        ch = *q;
        *q = *p;
        *p = ch;
        p--;
        q++;
    }

    if (len < width) {
        p = str_end;

        if (flag & FLAG_LEFT_ADJUST) {
            for (int i = 0; i < width - len; i++)
                *p++ = ' ';
            *p = '\0';
            str_end = p;
        } else {
            while (p >= str_first) {
                *(p + width - len) = *p;
                p--;
            }

            if (flag & FLAG_ZERO_PAD) {
                for (int i = 0; i < width - len; i++) {
                    num_str_buf[i + 1] = '0';
                }
            } else {
                for (int i = 0; i < width - len; i++)
                    str_first[i] = ' ';
            }
        }
    }

    return str_first;
}

char *int64_to_str_dec(int64_t num, int flag, int width) {
    return 0;
}

char *uint32_to_str_hex(uint32_t num, int flag, int width) {
    uint32_t num_tmp = num;
    char *p = num_str_buf;
    char *q = NULL;
    int len = 0;
    char *str_first = NULL;
    char *str_end = NULL;
    char ch = 0;

    memset(num_str_buf, 0, sizeof(num_str_buf));

    char dic_lower[] = {'0', '1', '2', '3', '4', '5', '6', '7',
                        '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'};
    char dic_upper[] = {'0', '1', '2', '3', '4', '5', '6', '7',
                        '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'};
    char *dic = (flag & FLAG_LOWER) ? dic_lower : dic_upper;

    str_first = num_str_buf;

    *p++ = '0';
    *p++ = (flag & FLAG_LOWER) ? 'x' : 'X';

    if (!(flag & FLAG_ALTNT_FORM)) {
        str_first += 2;
    }

    do {
        *p++ = dic[num_tmp % 16];
        num_tmp /= 16;
    } while (num_tmp);
    *p = '\0';

    str_end = p;
    len = str_end - str_first;

    q = num_str_buf + 2;
    p--;
    while (q < p) {
        ch = *q;
        *q = *p;
        *p = ch;
        p--;
        q++;
    }

    if (len < width) {
        p = str_end;

        if (flag & FLAG_LEFT_ADJUST) {
            for (int i = 0; i < width - len; i++)
                *p++ = ' ';
            *p = '\0';
            str_end = p;
        } else {
            while (p >= str_first) {
                *(p + width - len) = *p;
                p--;
            }
            if (flag & FLAG_ALTNT_FORM)
                str_first[1] = (flag & FLAG_LOWER) ? 'x' : 'X';

            if (flag & FLAG_ZERO_PAD) {
                for (int i = 0; i < width - len; i++) {
                    num_str_buf[i + 2] = '0';
                }
            } else {
                for (int i = 0; i < width - len; i++)
                    str_first[i] = ' ';
            }
        }
    }

    if (num == 0 && flag & FLAG_ALTNT_FORM)
        str_first[1] = '0';

    return str_first;
}

char *uint64_to_str_hex(uint64_t num, int flag, int width) {
    uint64_t num_tmp = num;
    char *p = num_str_buf;
    char *q = NULL;
    int len = 0;
    char *str_first = NULL;
    char *str_end = NULL;
    char ch = 0;

    memset(num_str_buf, 0, sizeof(num_str_buf));

    char dic_lower[] = {'0', '1', '2', '3', '4', '5', '6', '7',
                        '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'};
    char dic_upper[] = {'0', '1', '2', '3', '4', '5', '6', '7',
                        '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'};
    char *dic = (flag & FLAG_LOWER) ? dic_lower : dic_upper;

    str_first = num_str_buf;

    *p++ = '0';
    *p++ = (flag & FLAG_LOWER) ? 'x' : 'X';

    if (!(flag & FLAG_ALTNT_FORM)) {
        str_first += 2;
    }

    while (num_tmp) {
        *p++ = dic[num_tmp % 16];
        num_tmp /= 16;
    }
    *p = '\0';

    str_end = p;
    len = str_end - str_first;

    q = num_str_buf + 2;
    p--;
    while (q < p) {
        ch = *q;
        *q = *p;
        *p = ch;
        p--;
        q++;
    }

    if (len < width) {
        p = str_end;

        while (p >= str_first) {
            *(p + width - len) = *p;
            p--;
        }

        if (flag & FLAG_ZERO_PAD) {
            for (int i = 0; i < width - len; i++) {
                num_str_buf[i + 2] = '0';
            }
        } else {
            for (int i = 0; i < width - len; i++)
                str_first[i] = ' ';
        }
    }

    return str_first;
}

char *uint32_to_str_oct(uint32_t num, int flag, int width) {
    uint32_t num_tmp = num;
    char *p = num_str_buf;
    char *q = NULL;
    int len = 0;
    char *str_first = NULL;
    char *str_end = NULL;
    char ch = 0;

    memset(num_str_buf, 0, sizeof(num_str_buf));

    char dic[] = {'0', '1', '2', '3', '4', '5', '6', '7'};

    str_first = num_str_buf;

    *p++ = '0';

    if (!(flag & FLAG_ALTNT_FORM)) {
        str_first += 1;
    }

    while (num_tmp) {
        *p++ = dic[num_tmp % 8];
        num_tmp /= 8;
    }
    *p = '\0';

    str_end = p;
    len = str_end - str_first;

    q = num_str_buf + 1;
    p--;
    while (q < p) {
        ch = *q;
        *q = *p;
        *p = ch;
        p--;
        q++;
    }

    if (len < width) {
        p = str_end;

        if (flag & FLAG_LEFT_ADJUST) {
            for (int i = 0; i < width - len; i++)
                *p++ = ' ';
            *p = '\0';
            str_end = p;
        } else {
            while (p >= str_first) {
                *(p + width - len) = *p;
                p--;
            }

            if (flag & FLAG_ZERO_PAD) {
                for (int i = 0; i < width - len; i++) {
                    num_str_buf[i + 1] = '0';
                }
            } else {
                for (int i = 0; i < width - len; i++)
                    str_first[i] = ' ';
            }
        }
    }

    return str_first;
}

void insert_str(char *str, char *insert_str, int pos) {
    for (int i = 0; i < strlen(insert_str); i++) {
        insert_char(str, pos + i, insert_str[i]);
    }
}

void assert(int b, char *message) {
    if (!b) {
        printf("[KERNEL-PANIC]: %s", message);
        while (1) io_hlt();
    }
}

void trim(char *s) {
    char *p = s;
    int len = strlen(p);
    while (isspace(p[len - 1])) p[--len] = 0;
    while (*p && isspace(*p)) ++p, --len;
    memmove(s, p, len + 1);
}