#define CUSTOM_STRING_MAX_LEN 64

typedef struct {
    char buffer[CUSTOM_STRING_MAX_LEN];
    int length;  // current string length, excluding null terminator
} String;

// Initialize String to empty
void cs_init(String* cs)
{
    cs->buffer[0] = '\0';
    cs->length = 0;
}

// Set content from a C-string (truncates if needed)
void cs_set(String* cs, const char* src)
{
    int i = 0;
    while (src[i] != '\0' && i < (CUSTOM_STRING_MAX_LEN - 1))
    {
        cs->buffer[i] = src[i];
        i++;
    }
    cs->buffer[i] = '\0';
    cs->length = i;
}

// Compare two Strings for equality
int cs_equal(const String* a, const String* b)
{
    if (a->length != b->length)
        return 0;
    for (int i = 0; i < a->length; i++)
    {
        if (a->buffer[i] != b->buffer[i])
            return 0;
    }
    return 1;
}

// Check if String starts with another String prefix
int cs_starts_with(const String* cs, const String* prefix)
{
    if (prefix->length > cs->length)
        return 0;
    for (int i = 0; i < prefix->length; i++)
    {
        if (cs->buffer[i] != prefix->buffer[i])
            return 0;
    }
    return 1;
}

// Append a char to String (ignores if full)
void cs_append_char(String* cs, char c)
{
    if (cs->length < (CUSTOM_STRING_MAX_LEN - 1))
    {
        cs->buffer[cs->length++] = c;
        cs->buffer[cs->length] = '\0';
    }
}