use std::fmt;
use std::str;
#[cfg(test)] use super::encoding::*;
#[derive(Clone, PartialEq, Debug)]
pub struct QualityItem<T> {
pub item: T,
pub quality: f32,
}
impl<T> QualityItem<T> {
pub fn new(item: T, quality: f32) -> QualityItem<T> {
QualityItem{item: item, quality: quality}
}
}
impl<T: fmt::Display> fmt::Display for QualityItem<T> {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
if self.quality == 1.0 {
write!(f, "{}", self.item)
} else {
write!(f, "{}; q={}", self.item,
format!("{:.3}", self.quality).trim_right_matches(&['0', '.'][]))
}
}
}
impl<T: str::FromStr> str::FromStr for QualityItem<T> {
type Err = ();
fn from_str(s: &str) -> Result<Self, ()> {
let mut raw_item = s;
let mut quality = 1f32;
let parts: Vec<&str> = s.rsplitn(1, ';').map(|x| x.trim()).collect();
if parts.len() == 2 {
let start = &parts[0][0..2];
if start == "q=" || start == "Q=" {
let q_part = &parts[0][2..parts[0].len()];
if q_part.len() > 5 {
return Err(());
}
let x: Result<f32, _> = q_part.parse();
match x {
Ok(q_value) => {
if 0f32 <= q_value && q_value <= 1f32 {
quality = q_value;
raw_item = parts[1];
} else {
return Err(());
}
},
Err(_) => return Err(()),
}
}
}
let x: Result<T, _> = raw_item.parse();
match x {
Ok(item) => {
Ok(QualityItem{ item: item, quality: quality, })
},
Err(_) => return Err(()),
}
}
}
pub fn qitem<T>(item: T) -> QualityItem<T> {
QualityItem::new(item, 1.0)
}
#[test]
fn test_quality_item_show1() {
let x = qitem(Chunked);
assert_eq!(format!("{}", x), "chunked");
}
#[test]
fn test_quality_item_show2() {
let x = QualityItem::new(Chunked, 0.001);
assert_eq!(format!("{}", x), "chunked; q=0.001");
}
#[test]
fn test_quality_item_show3() {
let x = QualityItem{
item: EncodingExt("identity".to_string()),
quality: 0.5f32,
};
assert_eq!(format!("{}", x), "identity; q=0.5");
}
#[test]
fn test_quality_item_from_str1() {
let x: Result<QualityItem<Encoding>, ()> = "chunked".parse();
assert_eq!(x.unwrap(), QualityItem{ item: Chunked, quality: 1f32, });
}
#[test]
fn test_quality_item_from_str2() {
let x: Result<QualityItem<Encoding>, ()> = "chunked; q=1".parse();
assert_eq!(x.unwrap(), QualityItem{ item: Chunked, quality: 1f32, });
}
#[test]
fn test_quality_item_from_str3() {
let x: Result<QualityItem<Encoding>, ()> = "gzip; q=0.5".parse();
assert_eq!(x.unwrap(), QualityItem{ item: Gzip, quality: 0.5f32, });
}
#[test]
fn test_quality_item_from_str4() {
let x: Result<QualityItem<Encoding>, ()> = "gzip; q=0.273".parse();
assert_eq!(x.unwrap(), QualityItem{ item: Gzip, quality: 0.273f32, });
}
#[test]
fn test_quality_item_from_str5() {
let x: Result<QualityItem<Encoding>, ()> = "gzip; q=0.2739999".parse();
assert_eq!(x, Err(()));
}