You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: atf.rs
    path of file: ./repos/ruffle/render/src
    
    the code of the file until where you have to start completion: use std::io::Read;

use byteorder::{BigEndian, ReadBytesExt};
use num_derive::FromPrimitive;
use num_traits::FromPrimitive;

pub struct ATFTexture {
    pub width: u32,
    pub height: u32,
    pub cubemap: bool,
    pub format: ATFFormat,
    pub mip_count: u8,
    // A nested array of `[0..num_faces][0..mip_count]`, where each
    // entry is the texture data for that mip level and face.
    pub face_mip_data: Vec<Vec<ATFTextureData>>,
}

#[derive(Clone)]
pub enum ATFTextureData {
    Unknown(Vec<u8>),
    JpegXR(Vec<u8>),
    CompressedAlpha {
        jpegxr_alpha: Vec<u8>,
        dxt1_alpha_compressed: Vec<u8>,
        jpegxr_bgr: Vec<u8>,
        dxt5_rgb_compressed: Vec<u8>,
    },
    CompressedRawAlpha {
        dxt5: Vec<u8>,
        pvrtc: Vec<u8>,
        etc1: Vec<u8>,
        etc2: Vec<u8>,
    },
}

#[derive(FromPrimitive, Debug)]
pub enum ATFFormat {
    RGB888 = 0,
    RGBA8888 = 1,
    Compressed = 2,
    RawCompressed = 3,
    CompressedAlpha = 4,
    RawCompressedAlpha = 5,
    CompressedLossy = 0xc,
    CompressedLossyAlpha = 0xd,
}

impl ATFTexture {
    pub fn from_bytes(mut bytes: &[u8]) -> Result<Self, Box<dyn std::error::Error>> {
        // Based on https://github.com/openfl/openfl/blob/develop/src/openfl/display3D/_internal/ATFReader.hx
        let bytes = &mut bytes;

        let mut string_bytes = [0; 3];
        by
    
    pub fn from_bytes(mut bytes: &[u8]) -> Result<Self, Box<dyn std::error::Error>> {
        // Based on https://github.com/openfl/openfl/blob/develop/src/openfl/display3D/_internal/ATFReader.hx
        let bytes = &mut bytes;

        let mut string_bytes = [0; 3];
        bytes.read_exact(&mut string_bytes)?;

        if &string_bytes != b"ATF" {
            return Err(format!("Invalid ATF signature {string_bytes:?}").into());
        }

        let version;
        let _length;
        let mut actual_mip_count = None;

        if bytes[3] == 0xFF {
            actual_mip_count = Some(bytes[2] >> 1);
            if actual_mip_count == Some(0) {
                actual_mip_count = None;
            }
            version = bytes[4];
            *bytes = &bytes[5..];
            _length = bytes.read_u32::<byteorder::LittleEndian>()?;
        } else {
            version = 0;
            _length = read_uint24(bytes)?;
        }

        let tdata = bytes.read_u8()?;
        let cubemap = (tdata >> 7) != 0;

        let format = ATFFormat::from_u8(tdata & 0x7f).ok_or_else(|| {
            format!(
                "Invalid ATF format {format} (version {version})",
                format = tdata & 0x7f,
                version = version
            )
        })?;
        let width = 1 << bytes.read_u8()?;
        let height = 1 << bytes.read_u8()?;

        let mip_count = bytes.read_u8()?;
        let mip_count = actual_mip_count.unwrap_or(mip_count);
        let num_faces = if cubemap { 6 } else { 1 };

        let mut face_mip_data = vec![vec![]; num_faces];

        #[allow(clippy::needless_range_loop)]
        for face in 0..num_faces {
            for _ in 0..mip_count {
                let read_len = |bytes: &mut &[u8]| -> Result<u32, Box<dyn std::error::Error>> {
                    if version == 0 {
                        Ok(read_uint24(bytes)?)
                    } else {
                        Ok(bytes.read_u32::<BigEndian>()?)
                    }
                };

                match format {
                    ATFFormat::RGB888 | ATFFormat::RGBA8888 => {
                        let len = read_len(bytes)?;
                        let mut data = vec![0; len as usize];
                        bytes.read_exact(&mut data)?;
                        face_mip_data[face].push(ATFTextureData::JpegXR(data));
                    }
                    ATFFormat::CompressedAlpha => {
                        let dxt1_alpha_len = read_len(bytes)? as usize;
                        let mut dxt1_alpha_compressed = vec![0; dxt1_alpha_len];
                        bytes.read_exact(&mut dxt1_alpha_compressed)?;

                        let alpha_jpegxr_len = read_len(bytes)? as usize;
                        let mut alpha_jpegxr = vec![0; alpha_jpegxr_len];
                        bytes.read_exact(&mut alpha_jpegxr)?;

                        let dxt5_rgb = read_len(bytes)? as usize;
                        let mut dxt5_rgb_compressed = vec![0; dxt5_rgb];
                        bytes.read_exact(&mut dxt5_rgb_compressed)?;

                        let bgr_jpegxr_len = read_len(bytes)? as usize;
                        let mut bgr_jpegxr = vec![0; bgr_jpegxr_len];
                        bytes.read_exact(&mut bgr_jpegxr)?;

                        for _ in 0..12 {
                            let len = read_len(bytes)? as usize;
                            *bytes = &bytes[len..];
                        }

                        face_mip_data[face].push(ATFTextureData::CompressedAlpha {
                            jpegxr_alpha: alpha_jpegxr,
                            dxt1_alpha_compressed,
                            jpegxr_bgr: bgr_jpegxr,
                            dxt5_rgb_compressed,
                        });
                    }
                    ATFFormat::RawCompressedAlpha => {
                        let dxt5_len = read_len(bytes)? as usize;
                        let mut dxt5 = vec![0; dxt5_len];
                        bytes.read_exact(&mut dxt5)?;

                        let pvrtc_len = read_len(bytes)? as usize;
                        let mut pvrtc = vec![0; pvrtc_len];
                        bytes.read_exact(&mut pvrtc)?;

                        let etc1_len = read_len(bytes)? as usize;
                        let mut etc1 = vec![0; etc1_len];
                        bytes.read_exact(&mut etc1)?;

                        let etc2_len = read_len(bytes)? as usize;
                        let mut etc2 = vec![0; etc2_len];
                        bytes.read_exact(&mut etc2)?;

                        face_mip_data[face].push(ATFTextureData::CompressedRawAlpha {
                            dxt5,
                            pvrtc,
                            etc1,
                            etc2,
                        });
                    }
                    _ => {
                        // All of the formats consist of a number of (u32_length, data[u32_length]) records.
                        // For now, we just combine them into a single buffer to allow parsing to succeed.
                        let num_records = match format {
                            ATFFormat::RawCompressed | ATFFormat::RawCompressedAlpha => 4,
                            ATFFormat::Compressed => 11,
                            ATFFormat::CompressedLossy => 12,
                            ATFFormat::CompressedLossyAlpha => 17,
                            ATFFormat::RGB888
                            | ATFFormat::RGBA8888
                            | ATFFormat::CompressedAlpha => unreachable!(),
                        };

                        let mut all_data = vec![];
                        for _ in 0..num_records {
                            let len = read_len(bytes)? as usize;
                            let orig_len = all_data.len();
                            all_data.resize(orig_len + len, 0);
                            bytes.read_exact(&mut all_data[orig_len..])?;
                        }
                        face_mip_data[face].push(ATFTextureData::Unknown(all_data));
                    }
                }
            }
        }
        Ok(ATFTexture {
            width,
            height,
            cubemap,
            format,
            mip_count,
            face_mip_data,
        })
    }