#include <luna/CString.h>
#include <luna/String.h>
#include <luna/StringView.h>

static const char* empty = "";

StringView::StringView()
{
    m_string = empty;
    m_length = 0;
}

StringView::StringView(const StringView& other)
{
    m_string = other.m_string;
    m_length = other.m_length;
}

StringView::StringView(const char* c_str)
{
    check(c_str);
    m_string = c_str;
    m_length = strlen(m_string);
}

StringView::StringView(const char* c_str, usize length)
{
    check(c_str);
    m_string = c_str;
    m_length = length;
}

const char& StringView::operator[](usize index) const
{
    expect(index < m_length, "index out of range");
    return m_string[index];
}

bool StringView::operator==(const char* other) const
{
    return !strcmp(m_string, other);
}

bool StringView::operator==(StringView other) const
{
    return !strcmp(m_string, other.m_string);
}

Result<Vector<String>> StringView::split(StringView delim) const
{
    Vector<String> result;
    String str;

    char* copy = strndup(m_string, m_length);

    char* segment = strtok(copy, delim.chars());
    if (!segment) goto end;

    str = TRY(String::from_cstring(segment));
    TRY(result.try_append(move(str)));

    while (true)
    {
        segment = strtok(nullptr, delim.chars());
        if (!segment) goto end;

        str = TRY(String::from_cstring(segment));
        TRY(result.try_append(move(str)));
    }

end:
    free_impl(copy);
    return result;
}

Result<String> StringView::to_string()
{
    return String::from_cstring(m_string);
}