/* This software is licensed by the MIT License, see LICENSE file */
/*                                Copyright © 2022 Gregory Lirent */

#include "include.h"


/*#####################################################################################################################*/


static char* string_info(const vtype_string* s, size_t* size, size_t* nmemb) {

    char* p;
    char* v;

    if (is_null(s->buffer) || !*s->buffer) {
        *size = *nmemb = 0;
        return s->buffer;
    }

    *size = *nmemb = strasciilen(s->buffer);
    p = s->buffer + *nmemb;

    if (!*p) return p;

    while (*(v = next_char(p))) {
        ++*size;
        *nmemb += v - p;
        p = v;
    }
    ++*size;
    *nmemb += v - p;

    return p;
}


static int fetch_pad(char buffer[4], int chr) {

    char* p;

    if (chr) {
        p = tochar_unicode(buffer, chr);
        chr = !is_null(p) ? p - buffer : 0;
    }

    if (!chr) {
       *buffer = ' ';
        chr    = 1;
    }

    return chr;
}


/*#####################################################################################################################*/


size_t string_align_center(vtype_string* x, size_t n, int pc) {

    char s[4];
    size_t l;
    size_t ls;
    size_t rs;
    char*  p;

    string_info(x, &ls, &l);

    if (ls < n) {
        pc = fetch_pad(s, pc);
        ls = n - ls;
        rs = ls / 2;
    } else return ls;

    x->buffer = p = realloc(x->buffer, l + ls*pc + 1);
    memmove(x->buffer + (ls -= rs)*pc, x->buffer, l);

    for (size_t i = 0; i < ls; ++i) {
        p = memcpy(p, s, pc) + pc;
    }

    p += l;

    for (size_t i = 0; i < rs; ++i) {
        p = memcpy(p, s, pc) + pc;
    }

    *p = 0;

    return n;
}


size_t string_align_right(vtype_string* x, size_t n, int pc) {

    char s[4];
    size_t l;
    size_t ls;
    char*  p;

    string_info(x, &ls, &l);

    if (ls < n) {
        pc = fetch_pad(s, pc);
        ls = n - ls;
    } else return ls;

    x->buffer = p = realloc(x->buffer, ++l + ls*pc);
    memmove(x->buffer + ls*pc, x->buffer, l);

    for (size_t i = 0; i < ls; ++i) {
        p = memcpy(p, s, pc) + pc;
    }

    return n;
}


size_t string_align_left(vtype_string* x, size_t n, int pc) {

    char s[4];
    size_t l;
    size_t rs;
    char*  p;

    string_info(x, &rs, &l);

    if (rs < n) {
        pc = fetch_pad(s, pc);
        rs = n - rs;
    } else return rs;

    x->buffer = realloc(x->buffer, l + rs*pc + 1);
    p = x->buffer + l;

    for (size_t i = 0; i < rs; ++i) {
        p = memcpy(p, s, pc) + pc;
    }

    *p = 0;

    return n;
}