use crate::{read::BufReadError, McBufReadable, McBufWritable};
use std::{
    io::{Read, Write},
    ops::Deref,
};

/// A Vec<u8> that isn't prefixed by a VarInt with the size.
#[derive(Debug, Clone, PartialEq, Eq, Hash)]
pub struct UnsizedByteArray(Vec<u8>);

impl Deref for UnsizedByteArray {
    type Target = Vec<u8>;

    fn deref(&self) -> &Self::Target {
        &self.0
    }
}

impl From<Vec<u8>> for UnsizedByteArray {
    fn from(vec: Vec<u8>) -> Self {
        Self(vec)
    }
}

impl From<&str> for UnsizedByteArray {
    fn from(s: &str) -> Self {
        Self(s.as_bytes().to_vec())
    }
}

/// Represents Java's BitSet, a list of bits.
#[derive(Debug, Clone, PartialEq, Eq, Hash)]
pub struct BitSet {
    data: Vec<u64>,
}

// the Index trait requires us to return a reference, but we can't do that
impl BitSet {
    pub fn index(&self, index: usize) -> bool {
        (self.data[index / 64] & (1u64 << (index % 64))) != 0
    }
}

impl McBufReadable for BitSet {
    fn read_from(buf: &mut impl Read) -> Result<Self, BufReadError> {
        Ok(Self {
            data: Vec::<u64>::read_from(buf)?,
        })
    }
}

impl McBufWritable for BitSet {
    fn write_into(&self, buf: &mut impl Write) -> Result<(), std::io::Error> {
        self.data.write_into(buf)
    }
}