1use std::io::{Read, Result};
2use std::time::{Duration, Instant};
3
4pub struct Progress<R> {
5    bytes: usize,
6    tick: Instant,
7    stream: R,
8}
9
10impl<R> Progress<R> {
11    pub fn new(stream: R) -> Self {
12        Progress {
13            bytes: 0,
14            tick: Instant::now() + Duration::from_millis(2000),
15            stream,
16        }
17    }
18}
19
20impl<R: Read> Read for Progress<R> {
21    fn read(&mut self, buf: &mut [u8]) -> Result<usize> {
22        let num = self.stream.read(buf)?;
23        self.bytes += num;
24        let now = Instant::now();
25        if now > self.tick {
26            self.tick = now + Duration::from_millis(500);
27            errorf!("downloading... {} bytes\n", self.bytes);
28        }
29        Ok(num)
30    }
31}
32
33impl<R> Drop for Progress<R> {
34    fn drop(&mut self) {
35        errorf!("done ({} bytes)\n", self.bytes);
36    }
37}
38