#include "lisp_string.h"

#include <stdarg.h>
#include <stdio.h>
#include <string.h>

LispVal *make_lisp_string(const char *data, size_t length, bool take,
                          bool copy) {
    LispString *obj = lisp_alloc_object(sizeof(LispString), TYPE_STRING);
    obj->owned = take;
    obj->length = length;
    if (copy) {
        obj->data = lisp_malloc(length + 1);
        memcpy(obj->data, data, length);
        obj->data[length] = '\0';
    } else {
        obj->data = (char *) data;
    }
    return obj;
}

LispVal *lisp_sprintf(const char *format, ...) {
    va_list args;
    va_start(args, format);
    LispVal *s = lisp_vsprintf(format, args);
    va_end(args);
    return s;
}

LispVal *lisp_vsprintf(const char *format, va_list args) {
    va_list args2;
    va_copy(args2, args);
    int needed = vsnprintf(NULL, 0, format, args2);
    va_end(args2);
    char *buffer = lisp_malloc(needed + 1);
    int printed = vsnprintf(buffer, needed + 1, format, args);
    assert(printed == needed);
    return make_lisp_string(buffer, printed, true, false);
}

DEFUN(strings_equal, "strings-equal", (LispVal * string1, LispVal *string2),
      "(string1 string2)", "") {
    CHECK_TYPE(string1, TYPE_STRING);
    CHECK_TYPE(string2, TYPE_STRING);
    if (((LispString *) string1)->length != ((LispString *) string2)->length) {
        return Qnil;
    }
    return memcmp(((LispString *) string1)->data,
                  ((LispString *) string2)->data,
                  ((LispString *) string1)->length)
                   == 0
               ? Qt
               : Qnil;
}

DEFUN(hash_string, "hash-string", (LispVal * string), "(string)", "") {
    CHECK_TYPE(string, TYPE_STRING);
    size_t len = ((LispString *) string)->length;
    const char *str = ((LispString *) string)->data;
    uintptr_t hash = 5381;
    for (size_t i = 0; i < len; ++i) {
        hash = ((hash << 5) + hash) + str[i];
    }
    return MAKE_FIXNUM(hash);
}

DEFUN(charp, "charp", (LispVal * obj), "(obj)", "") {
    if (!FIXNUMP(obj)) {
        return Qnil;
    }
    fixnum_t val = XFIXNUM(obj);
    return (val >= 0 && val <= 255) ? Qt : Qnil;
}

DEFINE_SYMBOL(char, "char");