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    use crate::Buf;

    use core::cmp;

    /// A `Buf` adapter which limits the bytes read from an underlying buffer.
    ///
    /// This struct is generally created by calling `take()` on `Buf`. See
    /// documentation of [`take()`](trait.BufExt.html#method.take) for more details.
    #[derive(Debug)]
    pub struct Take<T> {
        inner: T,
        limit: usize,
    }

    pub fn new<T>(inner: T, limit: usize) -> Take<T> {
        Take { inner, limit }
    }

    impl<T> Take<T> {
        /// Consumes this `Take`, returning the underlying value.
        ///
        /// # Examples
        ///
        /// ```rust
        /// use bytes::{Buf, BufMut};
        ///
        /// let mut buf = b"hello world".take(2);
        /// let mut dst = vec![];
        ///
        /// dst.put(&mut buf);
        /// assert_eq!(*dst, b"he"[..]);
        ///
        /// let mut buf = buf.into_inner();
        ///
        /// dst.clear();
        /// dst.put(&mut buf);
        /// assert_eq!(*dst, b"llo world"[..]);
        /// ```
        pub fn into_inner(self) -> T {
            self.inner
        }

        /// Gets a reference to the underlying `Buf`.
        ///
        /// It is inadvisable to directly read from the underlying `Buf`.
        ///
        /// # Examples
        ///
        /// ```rust
        /// use bytes::Buf;
        ///
        /// let buf = b"hello world".take(2);
        ///
        /// assert_eq!(11, buf.get_ref().remaining());
        /// ```
        pub fn get_ref(&self) -> &T {
            &self.inner
        }

        /// Gets a mutable reference to the underlying `Buf`.
        ///
        /// It is inadvisable to directly read from the underlying `Buf`.
        ///
        /// # Examples
        ///
        /// ```rust
        /// use bytes::{Buf, BufMut};
        ///
        /// let mut buf = b"hello world".take(2);
        /// let mut dst = vec![];
        ///
        /// buf.get_mut().advance(2);
        ///
        /// dst.put(&mut buf);
        /// assert_eq!(*dst, b"ll"[..]);
        /// ```
        pub fn get_mut(&mut self) -> &mut T {
            &mut self.inner
        }

        /// Returns the maximum number of bytes that can be read.
        ///
        /// # Note
        ///
        /// If the inner `Buf` has fewer bytes than indicated by this method then
        /// that is the actual number of available bytes.
        ///
        /// # Examples
        ///
        /// ```rust
        /// use bytes::Buf;
        ///
        /// let mut buf = b"hello world".take(2);
        ///
        /// assert_eq!(2, buf.limit());
        /// assert_eq!(b'h', buf.get_u8());
        /// assert_eq!(1, buf.limit());
        /// ```
        pub fn limit(&self) -> usize {
            self.limit
        }

        /// Sets the maximum number of bytes that can be read.
        ///
        /// # Note
        ///
        /// If the inner `Buf` has fewer bytes than `lim` then that is the actual
        /// number of available bytes.
        ///
        /// # Examples
        ///
        /// ```rust
        /// use bytes::{Buf, BufMut};
        ///
        /// let mut buf = b"hello world".take(2);
        /// let mut dst = vec![];
        ///
        /// dst.put(&mut buf);
        /// assert_eq!(*dst, b"he"[..]);
        ///
        /// dst.clear();
        ///
        /// buf.set_limit(3);
        /// dst.put(&mut buf);
        /// assert_eq!(*dst, b"llo"[..]);
        /// ```
        pub fn set_limit(&mut self, lim: usize) {
            self.limit = lim
        }
    }

    impl<T: Buf> Buf for Take<T> {
        fn remaining(&self) -> usize {
            cmp::min(self.inner.remaining(), self.limit)
        }

        fn chunk(&self) -> &[u8] {
            let bytes = self.inner.chunk();
            &bytes[..cmp::min(bytes.len(), self.limit)]
        }

        fn advance(&mut self, cnt: usize) {
            assert!(cnt <= self.limit);
            self.inner.advance(cnt);
            self.limit -= cnt;
        }
    }