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use crate::CurrencyAmount;
use std::collections::HashMap;
use std::convert::TryFrom;
#[cfg(feature = "serialize")]
use serde::{Deserialize, Serialize};
#[derive(Clone, Copy, Debug)]
#[cfg_attr(feature = "serde", derive(Deserialize, Serialize))]
pub struct Exponent {
pub amount: CurrencyAmount,
pub exponent: u8,
}
impl Exponent {
pub fn new(amount: CurrencyAmount, exponent: u8) -> Self {
Exponent { amount, exponent }
}
}
impl PartialEq for Exponent {
fn eq(&self, other: &Exponent) -> bool {
(self.amount / 10i128.pow(u32::from(self.exponent)).into())
== (other.amount / (10i128).pow(u32::from(other.exponent)).into())
}
}
#[derive(Debug, Clone, Default)]
pub struct Rates {
map: HashMap<CurrencyCode, CurrencyAmount>,
}
#[derive(Debug, Clone, Copy, Default, PartialEq, Eq, Hash)]
#[cfg_attr(feature = "serialize", derive(Serialize, Deserialize))]
pub struct CurrencyCode {
code: [u8; 3],
}
impl std::ops::Deref for CurrencyCode {
type Target = [u8; 3];
fn deref(&self) -> &Self::Target {
&self.code
}
}
impl Rates {
pub fn new() -> Self {
Rates::default()
}
pub fn with_rates(map: HashMap<CurrencyCode, CurrencyAmount>) -> Self {
Rates { map }
}
pub fn worth(&self, code: CurrencyCode) -> Option<CurrencyAmount> {
self.map.get(&code).cloned()
}
}
impl<'s> TryFrom<&'s str> for CurrencyCode {
type Error = String;
fn try_from(s: &'s str) -> Result<Self, Self::Error> {
if s.len() != 3 {
Err(format!("Given string has not length 3: \"{}\"", s))
} else {
let bytes = s.as_bytes();
Ok(CurrencyCode {
code: [bytes[0], bytes[1], bytes[2]],
})
}
}
}
impl<'a> TryFrom<&'a CurrencyCode> for &'a str {
type Error = std::str::Utf8Error;
fn try_from(code: &'a CurrencyCode) -> Result<Self, Self::Error> {
std::str::from_utf8(&code[..])
}
}