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: xsettings.rs
    path of file: ./repos/wezterm/window/src/os/x11
    
    the code of the file until where you have to start completion: use anyhow::Context;
/// This module parses xsettings data.
/// The data format is slightly incorrectly documented here:
/// <https://specifications.freedesktop.org/xsettings-spec/xsettings-latest.html>
/// I looked at the libxsettings-client sources to verify the behavior;
/// there is a discrepancy in the representation of string setting lengths,
/// but otherwise it seems to parse the data from my 2021 gnome window environment.
use bytes::Buf;
use std::collections::BTreeMap;
use xcb::x::Atom;

pub type XSettingsMap = BTreeMap<String, XSetting>;

#[derive(Debug, PartialEq, Eq)]
pub enum XSetting {
    Integer(i32),
    String(String),
    Color(u16, u16, u16, u16),
}

fn read_xsettings_grabbed(
    conn: &xcb::Connection,
    atom_xsettings_selection: Atom,
   
    
pub fn parse_xsettings(data: &[u8]) -> anyhow::Result<XSettingsMap> {
    anyhow::ensure!(data.len() > 0);

    let mut settings = BTreeMap::new();

    let mut buf = data;
    let is_big_endian = buf.get_u8() != 0;

    fn get_u8<BUF: Buf>(buf: &mut BUF) -> anyhow::Result<u8> {
        anyhow::ensure!(buf.remaining() >= 1);
        Ok(buf.get_u8())
    }
    fn get_u16<BUF: Buf>(buf: &mut BUF, is_big_endian: bool) -> anyhow::Result<u16> {
        anyhow::ensure!(buf.remaining() >= 2);
        Ok(if is_big_endian {
            buf.get_u16()
        } else {
            buf.get_u16_le()
        })
    }
    fn get_u32<BUF: Buf>(buf: &mut BUF, is_big_endian: bool) -> anyhow::Result<u32> {
        anyhow::ensure!(buf.remaining() >= 4);
        Ok(if is_big_endian {
            buf.get_u32()
        } else {
            buf.get_u32_le()
        })
    }
    fn get_i32<BUF: Buf>(buf: &mut BUF, is_big_endian: bool) -> anyhow::Result<i32> {
        anyhow::ensure!(buf.remaining() >= 4);
        Ok(if is_big_endian {
            buf.get_i32()
        } else {
            buf.get_i32_le()
        })
    }
    fn advance<BUF: Buf>(buf: &mut BUF, n: usize) -> anyhow::Result<()> {
        anyhow::ensure!(buf.remaining() >= n);
        buf.advance(n);
        Ok(())
    }

    advance(&mut buf, 3)?;
    let _serial = get_u32(&mut buf, is_big_endian)?;
    let num_settings = get_u32(&mut buf, is_big_endian)? as usize;

    fn pad(len: usize) -> usize {
        (len + 3) & !3
    }

    for _ in 0..num_settings {
        let setting_type = get_u8(&mut buf)?;
        advance(&mut buf, 1)?;
        let name_len = get_u16(&mut buf, is_big_endian)? as usize;
        let padded_name_len = pad(name_len);
        anyhow::ensure!(
            buf.remaining() >= padded_name_len,
            "name_len is {} (pad: {}) but buffer has {} remaining",
            name_len,
            padded_name_len,
            buf.remaining()
        );
        let name = String::from_utf8(buf.chunk()[..name_len].to_vec())?;
        buf.advance(padded_name_len);

        let _last_change_serial = get_u32(&mut buf, is_big_endian)?;

        let value = match setting_type {
            0 => XSetting::Integer(get_i32(&mut buf, is_big_endian)?),
            1 => {
                // Note that the xsettings-latest spec indicates that this
                // length is a u16, but that fails to parse real data,
                // and libxsettings-client treats it as u32, so we do too.
                let s_len = get_u32(&mut buf, is_big_endian)? as usize;
                let padded_s_len = pad(s_len);
                anyhow::ensure!(
                    buf.remaining() >= padded_s_len,
                    "s_len is {} (pad: {}) but buffer has {} remaining",
                    s_len,
                    padded_s_len,
                    buf.remaining()
                );
                let s = String::from_utf8(buf.chunk()[..s_len].to_vec())?;
                buf.advance(padded_s_len);

                XSetting::String(s)
            }
            2 => {
                let red = get_u16(&mut buf, is_big_endian)?;
                let green = get_u16(&mut buf, is_big_endian)?;
                let blue = get_u16(&mut buf, is_big_endian)?;
                let alpha = get_u16(&mut buf, is_big_endian)?;
                XSetting::Color(red, green, blue, alpha)
            }
            n => anyhow::bail!("invalid setting type {}, expected, 0, 1 or 2", n),
        };
        settings.insert(name, value);
    }

    Ok(settings)
}