libpso/src/lib.rs

pub mod crypto;
pub mod packet;
pub mod character;

use std::io::Read;
#[derive(Debug, PartialEq)]
pub enum PacketParseError {
    NotEnoughBytes,
    WrongPacketCommand,
    WrongPacketForServerType,
    WrongPacketSize(u16, usize),
    DataStructNotLargeEnough(u64, usize),
    InvalidValue,
    ReadError,
}


trait PSOPacketData {
    //fn size(&self) -> usize;
    fn from_bytes<R: Read>(cursor: &mut R) -> Result<Self, PacketParseError> where Self: Sized;
    fn as_bytes(&self) -> Vec<u8>;
}

impl PSOPacketData for u8 {
    fn from_bytes<R: Read>(cursor: &mut R) -> Result<u8, PacketParseError>  {
        let mut bytes = [0u8; 1];
        cursor.read(&mut bytes).map_err(|_| PacketParseError::ReadError)?;
        Ok(bytes[0])
    }
    fn as_bytes(&self) -> Vec<u8> {
        vec![*self]
    }
}

impl PSOPacketData for u32 {
    fn from_bytes<R: Read>(cursor: &mut R) -> Result<u32, PacketParseError>  {
        let mut bytes = [0u8; 4];
        cursor.read(&mut bytes).map_err(|_| PacketParseError::ReadError)?;
        Ok(u32::from_le_bytes(bytes))
    }
    fn as_bytes(&self) -> Vec<u8> {
        u32::to_le_bytes(*self).to_vec()
    }
}

impl PSOPacketData for u16 {
    fn from_bytes<R: Read>(cursor: &mut R) -> Result<u16, PacketParseError>  {
        let mut bytes = [0u8; 2];
        cursor.read(&mut bytes).map_err(|_| PacketParseError::ReadError)?;
        Ok(u16::from_le_bytes(bytes))
    }
    fn as_bytes(&self) -> Vec<u8> {
        u16::to_le_bytes(*self).to_vec()
    }
}

impl PSOPacketData for String {
    fn from_bytes<R: Read>(cursor: &mut R) -> Result<String, PacketParseError>  {
        let mut s: Vec<u8> = Vec::new();
        cursor.read_to_end(&mut s).map_err(|_| PacketParseError::ReadError)?;
        let mut utf16 = Vec::new();
        for c in s.chunks(2) {
            utf16.push(u16::from_le_bytes([c[0], c[1]]));
        }
        Ok(String::from_utf16_lossy(utf16.as_slice()))
    }
    fn as_bytes(&self) -> Vec<u8> {
        let mut buf = Vec::new();
        for c in self.as_str().encode_utf16() {
            buf.extend_from_slice(&c.to_le_bytes());
        }
        buf
    }
}


pub trait PSOPacket: std::fmt::Debug {
    fn from_bytes(data: &[u8]) -> Result<Self, PacketParseError> where Self: Sized;
    fn as_bytes(&self) -> Vec<u8>;
}