use crate::error::FinError;
use crate::signals::{BarInput, Signal, SignalValue};
use rust_decimal::Decimal;
pub struct ConsecutiveHigherHighs {
name: String,
prev_high: Option<Decimal>,
streak: i64,
}
impl ConsecutiveHigherHighs {
pub fn new(name: impl Into<String>) -> Self {
Self { name: name.into(), prev_high: None, streak: 0 }
}
}
impl Signal for ConsecutiveHigherHighs {
fn name(&self) -> &str {
&self.name
}
fn update(&mut self, bar: &BarInput) -> Result<SignalValue, FinError> {
let result = if let Some(prev) = self.prev_high {
if bar.high > prev {
self.streak = if self.streak > 0 { self.streak + 1 } else { 1 };
} else if bar.high < prev {
self.streak = if self.streak < 0 { self.streak - 1 } else { -1 };
} else {
self.streak = 0;
}
SignalValue::Scalar(Decimal::from(self.streak))
} else {
SignalValue::Unavailable
};
self.prev_high = Some(bar.high);
Ok(result)
}
fn is_ready(&self) -> bool {
self.prev_high.is_some()
}
fn period(&self) -> usize {
2
}
fn reset(&mut self) {
self.prev_high = None;
self.streak = 0;
}
}
#[cfg(test)]
mod tests {
use super::*;
use crate::ohlcv::OhlcvBar;
use crate::signals::Signal;
use crate::types::{NanoTimestamp, Price, Quantity, Symbol};
use rust_decimal_macros::dec;
fn bar(high: &str) -> OhlcvBar {
let h = Price::new(high.parse().unwrap()).unwrap();
let l = Price::new("1".parse().unwrap()).unwrap();
OhlcvBar {
symbol: Symbol::new("X").unwrap(),
open: l, high: h, low: l, close: h,
volume: Quantity::zero(),
ts_open: NanoTimestamp::new(0),
ts_close: NanoTimestamp::new(1),
tick_count: 1,
}
}
#[test]
fn test_first_bar_unavailable() {
let mut chh = ConsecutiveHigherHighs::new("chh");
assert_eq!(chh.update_bar(&bar("15")).unwrap(), SignalValue::Unavailable);
}
#[test]
fn test_consecutive_higher_highs() {
let mut chh = ConsecutiveHigherHighs::new("chh");
chh.update_bar(&bar("10")).unwrap();
assert_eq!(chh.update_bar(&bar("12")).unwrap(), SignalValue::Scalar(dec!(1)));
assert_eq!(chh.update_bar(&bar("14")).unwrap(), SignalValue::Scalar(dec!(2)));
assert_eq!(chh.update_bar(&bar("16")).unwrap(), SignalValue::Scalar(dec!(3)));
}
#[test]
fn test_consecutive_lower_highs() {
let mut chh = ConsecutiveHigherHighs::new("chh");
chh.update_bar(&bar("16")).unwrap();
assert_eq!(chh.update_bar(&bar("14")).unwrap(), SignalValue::Scalar(dec!(-1)));
assert_eq!(chh.update_bar(&bar("12")).unwrap(), SignalValue::Scalar(dec!(-2)));
}
#[test]
fn test_equal_resets() {
let mut chh = ConsecutiveHigherHighs::new("chh");
chh.update_bar(&bar("10")).unwrap();
chh.update_bar(&bar("12")).unwrap();
chh.update_bar(&bar("14")).unwrap();
assert_eq!(chh.update_bar(&bar("14")).unwrap(), SignalValue::Scalar(dec!(0)));
assert_eq!(chh.update_bar(&bar("15")).unwrap(), SignalValue::Scalar(dec!(1)));
}
#[test]
fn test_reset() {
let mut chh = ConsecutiveHigherHighs::new("chh");
chh.update_bar(&bar("10")).unwrap();
chh.update_bar(&bar("12")).unwrap();
assert!(chh.is_ready());
chh.reset();
assert!(!chh.is_ready());
}
}