feat(patterns): add the Harmonic Patterns family (8 XABCD detectors) (#169)

## Summary Adds a new **Harmonic Patterns** indicator family (counter 359 → 367, families 22 → 23) — the second half of the A4 roadmap item, following the Chart Patterns family in #166. Eight Fibonacci-ratio detectors built on the shared swing-pivot tracker (`indicators::pattern_swing`) plus two new helpers there — `xabcd` (reads the last five pivots as X-A-B-C-D) and `ratios_in` (checks a list of `(value, low, high)` Fibonacci windows in one expression, no multi-line `&&` coverage gaps). Each consumes candles and emits the uniform pattern sign convention — `+1.0` bullish (terminal point D a swing low), `-1.0` bearish (D a swing high), `0.0` otherwise, never `None`. Parameter-free, with the Fibonacci windows documented as constants per detector. ## Detectors | Indicator | Defining ratio | |-----------|----------------| | `Abcd` | four-point AB=CD (BC retraces AB, CD ≈ AB) | | `Gartley` | AD/XA ≈ 0.786 | | `Butterfly` | AD/XA ∈ 1.27–1.618 (extended D) | | `Bat` | AD/XA ≈ 0.886, shallow B | | `Crab` | AD/XA ≈ 1.618 (deepest D) | | `Shark` | expansion AB, AD/XA 0.886–1.13 | | `Cypher` | BC on XA, CD/XC ≈ 0.786 | | `ThreeDrives` | two symmetric extension drives | ## Touchpoints Core modules + `FAMILIES` group/assert, crate root re-exports, Python/Node/WASM bindings via the candle-pattern macros (Node `index.d.ts`/`index.js` regenerated), the candle fuzz target (`// --- Harmonic Patterns ---` section), Python reference + `CANDLE_SCALAR` registry tests and the Node candle-scalar factory, README catalogue counter + banner cache-buster + family table row + family-count word, `docs/README.md` counter, and the changelog. ## Verification - `cargo test -p wickra-core --lib` — 2966 passed - `cargo test -p wickra-core --doc` — 335 passed - `cargo clippy --workspace --all-targets --all-features -- -D warnings` — clean - Node `npm run build && npm test` — 444 passed - Python `maturin develop --release` + `pytest` — 748 passed Every detector branch is unit-tested, including a bullish and a bearish match per pattern to cover both output arms, plus an out-of-ratio non-match. Fibonacci windows use standard harmonic-trading ranges with documented tolerance bands.
2026-06-03 23:24:25 +02:00
parent 995f119010
commit 4250ed99f4
23 changed files with 1649 additions and 26 deletions
@@ -0,0 +1,154 @@
+//! AB=CD harmonic pattern.
+
+use crate::indicators::pattern_swing::{approx_equal, ratios_in, SwingTracker, SWING_THRESHOLD};
+use crate::ohlcv::Candle;
+use crate::traits::Indicator;
+
+/// AB=CD — the simplest four-point harmonic pattern: an A→B leg, a B→C
+/// retracement, and a C→D leg that mirrors A→B in length:
+///
+/// ```text
+/// BC / AB ∈ [0.382, 0.886]   (C retraces AB)
+/// CD / BC ∈ [1.13, 2.618]    (D extends BC)
+/// AB ≈ CD (within 10%)        (the two legs are equal — the defining symmetry)
+/// ```
+///
+/// Read from the last four confirmed pivots `A-B-C-D`. Output is `+1.0`
+/// (bullish, D a swing low), `-1.0` (bearish, D a swing high), or `0.0`; never
+/// `None`. See `crates/wickra-core/src/indicators/abcd.rs`.
+#[derive(Debug, Clone)]
+pub struct Abcd {
+    swing: SwingTracker,
+    has_emitted: bool,
+}
+
+impl Abcd {
+    /// Construct a new AB=CD detector.
+    pub const fn new() -> Self {
+        Self {
+            swing: SwingTracker::new(SWING_THRESHOLD, 4),
+            has_emitted: false,
+        }
+    }
+}
+
+impl Default for Abcd {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+impl Indicator for Abcd {
+    type Input = Candle;
+    type Output = f64;
+
+    fn update(&mut self, candle: Candle) -> Option<f64> {
+        self.has_emitted = true;
+        if !self.swing.update(candle) {
+            return Some(0.0);
+        }
+        let pivots = self.swing.pivots();
+        if pivots.len() < 4 {
+            return Some(0.0);
+        }
+        let len = pivots.len();
+        let pa = pivots[len - 4];
+        let pb = pivots[len - 3];
+        let pc = pivots[len - 2];
+        let pd = pivots[len - 1];
+        let ab = (pb.price - pa.price).abs();
+        let bc = (pc.price - pb.price).abs();
+        let cd = (pd.price - pc.price).abs();
+        let ratios_ok = ratios_in(&[(bc / ab, 0.382, 0.886), (cd / bc, 1.13, 2.618)]);
+        let legs_equal = approx_equal(ab, cd, 0.10);
+        if ratios_ok && legs_equal {
+            return Some(if pd.direction < 0.0 { 1.0 } else { -1.0 });
+        }
+        Some(0.0)
+    }
+
+    fn reset(&mut self) {
+        self.swing.reset();
+        self.has_emitted = false;
+    }
+
+    fn warmup_period(&self) -> usize {
+        5
+    }
+
+    fn is_ready(&self) -> bool {
+        self.has_emitted
+    }
+
+    fn name(&self) -> &'static str {
+        "Abcd"
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::indicators::pattern_swing::candles_for_pivots;
+    use crate::traits::BatchExt;
+
+    fn run(pivots: &[f64]) -> Vec<f64> {
+        let mut indicator = Abcd::new();
+        candles_for_pivots(pivots)
+            .into_iter()
+            .map(|c| indicator.update(c).unwrap())
+            .collect()
+    }
+
+    #[test]
+    fn accessors_and_metadata() {
+        let indicator = Abcd::new();
+        assert_eq!(indicator.name(), "Abcd");
+        assert_eq!(indicator.warmup_period(), 5);
+        assert!(!indicator.is_ready());
+        assert!(!Abcd::default().is_ready());
+    }
+
+    #[test]
+    fn bullish_abcd_is_plus_one() {
+        // AB = 40 down, BC = 24.7 up (0.618), CD = 40 down → AB = CD.
+        let out = run(&[140.0, 100.0, 124.7, 84.7]);
+        assert_eq!(*out.last().unwrap(), 1.0);
+        assert!(out[..out.len() - 1].iter().all(|&x| x == 0.0));
+    }
+
+    #[test]
+    fn bearish_abcd_is_minus_one() {
+        let out = run(&[150.0, 100.0, 140.0, 115.3, 155.3]);
+        assert_eq!(*out.last().unwrap(), -1.0);
+    }
+
+    #[test]
+    fn unequal_legs_do_not_trigger() {
+        // CD (82) far longer than AB (40) → not an AB=CD.
+        let out = run(&[150.0, 100.0, 140.0, 118.0, 200.0]);
+        assert_eq!(*out.last().unwrap(), 0.0);
+    }
+
+    #[test]
+    fn reset_clears_state() {
+        let mut indicator = Abcd::new();
+        for c in candles_for_pivots(&[140.0, 100.0, 124.7]) {
+            let _ = indicator.update(c);
+        }
+        indicator.reset();
+        assert!(!indicator.is_ready());
+        let c = Candle::new(99.5, 100.0, 99.5, 99.5, 1.0, 0).unwrap();
+        assert_eq!(indicator.update(c), Some(0.0));
+    }
+
+    #[test]
+    fn batch_equals_streaming() {
+        let candles = candles_for_pivots(&[140.0, 100.0, 124.7, 84.7]);
+        let mut a = Abcd::new();
+        let mut b = Abcd::new();
+        assert_eq!(
+            a.batch(&candles),
+            candles.iter().map(|x| b.update(*x)).collect::<Vec<_>>()
+        );
+    }
+}
@@ -0,0 +1,154 @@
+//! Bat harmonic pattern.
+
+use crate::indicators::pattern_swing::{ratios_in, xabcd, SwingTracker, SWING_THRESHOLD};
+use crate::ohlcv::Candle;
+use crate::traits::Indicator;
+
+/// Bat — a 5-point (X-A-B-C-D) harmonic pattern with a shallow B and a deep
+/// `0.886` D completion:
+///
+/// ```text
+/// AB / XA ∈ [0.382, 0.50]
+/// BC / AB ∈ [0.382, 0.886]
+/// CD / BC ∈ [1.618, 2.618]
+/// AD / XA ∈ [0.84, 0.93]   (≈ 0.886 — the defining D completion)
+/// ```
+///
+/// Output is `+1.0` (bullish, D a swing low), `-1.0` (bearish, D a swing high),
+/// or `0.0`; never `None`. See `crates/wickra-core/src/indicators/bat.rs`.
+#[derive(Debug, Clone)]
+pub struct Bat {
+    swing: SwingTracker,
+    has_emitted: bool,
+}
+
+impl Bat {
+    /// Construct a new Bat detector.
+    pub const fn new() -> Self {
+        Self {
+            swing: SwingTracker::new(SWING_THRESHOLD, 5),
+            has_emitted: false,
+        }
+    }
+}
+
+impl Default for Bat {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+impl Indicator for Bat {
+    type Input = Candle;
+    type Output = f64;
+
+    fn update(&mut self, candle: Candle) -> Option<f64> {
+        self.has_emitted = true;
+        if !self.swing.update(candle) {
+            return Some(0.0);
+        }
+        let pivots = self.swing.pivots();
+        if pivots.len() < 5 {
+            return Some(0.0);
+        }
+        let p = xabcd(pivots);
+        let xa = (p.a - p.x).abs();
+        let ab = (p.b - p.a).abs();
+        let bc = (p.c - p.b).abs();
+        let cd = (p.d - p.c).abs();
+        let ad = (p.d - p.a).abs();
+        let matched = ratios_in(&[
+            (ab / xa, 0.382, 0.50),
+            (bc / ab, 0.382, 0.886),
+            (cd / bc, 1.618, 2.618),
+            (ad / xa, 0.84, 0.93),
+        ]);
+        if matched {
+            return Some(if p.bullish { 1.0 } else { -1.0 });
+        }
+        Some(0.0)
+    }
+
+    fn reset(&mut self) {
+        self.swing.reset();
+        self.has_emitted = false;
+    }
+
+    fn warmup_period(&self) -> usize {
+        6
+    }
+
+    fn is_ready(&self) -> bool {
+        self.has_emitted
+    }
+
+    fn name(&self) -> &'static str {
+        "Bat"
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::indicators::pattern_swing::candles_for_pivots;
+    use crate::traits::BatchExt;
+
+    fn run(pivots: &[f64]) -> Vec<f64> {
+        let mut indicator = Bat::new();
+        candles_for_pivots(pivots)
+            .into_iter()
+            .map(|c| indicator.update(c).unwrap())
+            .collect()
+    }
+
+    #[test]
+    fn accessors_and_metadata() {
+        let indicator = Bat::new();
+        assert_eq!(indicator.name(), "Bat");
+        assert_eq!(indicator.warmup_period(), 6);
+        assert!(!indicator.is_ready());
+        assert!(!Bat::default().is_ready());
+    }
+
+    #[test]
+    fn bullish_bat_is_plus_one() {
+        let out = run(&[150.0, 100.0, 140.0, 122.0, 137.0, 104.56]);
+        assert_eq!(*out.last().unwrap(), 1.0);
+        assert!(out[..out.len() - 1].iter().all(|&x| x == 0.0));
+    }
+
+    #[test]
+    fn bearish_bat_is_minus_one() {
+        let out = run(&[150.0, 110.0, 128.0, 113.0, 145.44]);
+        assert_eq!(*out.last().unwrap(), -1.0);
+    }
+
+    #[test]
+    fn out_of_ratio_does_not_trigger() {
+        let out = run(&[150.0, 100.0, 140.0, 110.0, 135.0, 105.0]);
+        assert_eq!(*out.last().unwrap(), 0.0);
+    }
+
+    #[test]
+    fn reset_clears_state() {
+        let mut indicator = Bat::new();
+        for c in candles_for_pivots(&[150.0, 100.0, 140.0]) {
+            let _ = indicator.update(c);
+        }
+        indicator.reset();
+        assert!(!indicator.is_ready());
+        let c = Candle::new(99.5, 100.0, 99.5, 99.5, 1.0, 0).unwrap();
+        assert_eq!(indicator.update(c), Some(0.0));
+    }
+
+    #[test]
+    fn batch_equals_streaming() {
+        let candles = candles_for_pivots(&[150.0, 100.0, 140.0, 122.0, 137.0, 104.56]);
+        let mut a = Bat::new();
+        let mut b = Bat::new();
+        assert_eq!(
+            a.batch(&candles),
+            candles.iter().map(|x| b.update(*x)).collect::<Vec<_>>()
+        );
+    }
+}
@@ -0,0 +1,154 @@
+//! Butterfly harmonic pattern.
+
+use crate::indicators::pattern_swing::{ratios_in, xabcd, SwingTracker, SWING_THRESHOLD};
+use crate::ohlcv::Candle;
+use crate::traits::Indicator;
+
+/// Butterfly — a 5-point (X-A-B-C-D) harmonic pattern with a `0.786` B and an
+/// **extended** D that overshoots X:
+///
+/// ```text
+/// AB / XA ∈ [0.74, 0.84]   (≈ 0.786)
+/// BC / AB ∈ [0.382, 0.886]
+/// CD / BC ∈ [1.618, 2.618]
+/// AD / XA ∈ [1.27, 1.618]  (the defining extended D completion)
+/// ```
+///
+/// Output is `+1.0` (bullish, D a swing low), `-1.0` (bearish, D a swing high),
+/// or `0.0`; never `None`. See `crates/wickra-core/src/indicators/butterfly.rs`.
+#[derive(Debug, Clone)]
+pub struct Butterfly {
+    swing: SwingTracker,
+    has_emitted: bool,
+}
+
+impl Butterfly {
+    /// Construct a new Butterfly detector.
+    pub const fn new() -> Self {
+        Self {
+            swing: SwingTracker::new(SWING_THRESHOLD, 5),
+            has_emitted: false,
+        }
+    }
+}
+
+impl Default for Butterfly {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+impl Indicator for Butterfly {
+    type Input = Candle;
+    type Output = f64;
+
+    fn update(&mut self, candle: Candle) -> Option<f64> {
+        self.has_emitted = true;
+        if !self.swing.update(candle) {
+            return Some(0.0);
+        }
+        let pivots = self.swing.pivots();
+        if pivots.len() < 5 {
+            return Some(0.0);
+        }
+        let p = xabcd(pivots);
+        let xa = (p.a - p.x).abs();
+        let ab = (p.b - p.a).abs();
+        let bc = (p.c - p.b).abs();
+        let cd = (p.d - p.c).abs();
+        let ad = (p.d - p.a).abs();
+        let matched = ratios_in(&[
+            (ab / xa, 0.74, 0.84),
+            (bc / ab, 0.382, 0.886),
+            (cd / bc, 1.618, 2.618),
+            (ad / xa, 1.27, 1.618),
+        ]);
+        if matched {
+            return Some(if p.bullish { 1.0 } else { -1.0 });
+        }
+        Some(0.0)
+    }
+
+    fn reset(&mut self) {
+        self.swing.reset();
+        self.has_emitted = false;
+    }
+
+    fn warmup_period(&self) -> usize {
+        6
+    }
+
+    fn is_ready(&self) -> bool {
+        self.has_emitted
+    }
+
+    fn name(&self) -> &'static str {
+        "Butterfly"
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::indicators::pattern_swing::candles_for_pivots;
+    use crate::traits::BatchExt;
+
+    fn run(pivots: &[f64]) -> Vec<f64> {
+        let mut indicator = Butterfly::new();
+        candles_for_pivots(pivots)
+            .into_iter()
+            .map(|c| indicator.update(c).unwrap())
+            .collect()
+    }
+
+    #[test]
+    fn accessors_and_metadata() {
+        let indicator = Butterfly::new();
+        assert_eq!(indicator.name(), "Butterfly");
+        assert_eq!(indicator.warmup_period(), 6);
+        assert!(!indicator.is_ready());
+        assert!(!Butterfly::default().is_ready());
+    }
+
+    #[test]
+    fn bullish_butterfly_is_plus_one() {
+        let out = run(&[150.0, 100.0, 140.0, 108.6, 128.0, 79.8]);
+        assert_eq!(*out.last().unwrap(), 1.0);
+        assert!(out[..out.len() - 1].iter().all(|&x| x == 0.0));
+    }
+
+    #[test]
+    fn bearish_butterfly_is_minus_one() {
+        let out = run(&[150.0, 110.0, 141.4, 121.4, 170.2]);
+        assert_eq!(*out.last().unwrap(), -1.0);
+    }
+
+    #[test]
+    fn out_of_ratio_does_not_trigger() {
+        let out = run(&[150.0, 100.0, 140.0, 110.0, 135.0, 105.0]);
+        assert_eq!(*out.last().unwrap(), 0.0);
+    }
+
+    #[test]
+    fn reset_clears_state() {
+        let mut indicator = Butterfly::new();
+        for c in candles_for_pivots(&[150.0, 100.0, 140.0]) {
+            let _ = indicator.update(c);
+        }
+        indicator.reset();
+        assert!(!indicator.is_ready());
+        let c = Candle::new(99.5, 100.0, 99.5, 99.5, 1.0, 0).unwrap();
+        assert_eq!(indicator.update(c), Some(0.0));
+    }
+
+    #[test]
+    fn batch_equals_streaming() {
+        let candles = candles_for_pivots(&[150.0, 100.0, 140.0, 108.6, 128.0, 79.8]);
+        let mut a = Butterfly::new();
+        let mut b = Butterfly::new();
+        assert_eq!(
+            a.batch(&candles),
+            candles.iter().map(|x| b.update(*x)).collect::<Vec<_>>()
+        );
+    }
+}
@@ -0,0 +1,154 @@
+//! Crab harmonic pattern.
+
+use crate::indicators::pattern_swing::{ratios_in, xabcd, SwingTracker, SWING_THRESHOLD};
+use crate::ohlcv::Candle;
+use crate::traits::Indicator;
+
+/// Crab — a 5-point (X-A-B-C-D) harmonic pattern with the deepest D completion
+/// of the family, an `1.618` extension of XA:
+///
+/// ```text
+/// AB / XA ∈ [0.382, 0.618]
+/// BC / AB ∈ [0.382, 0.886]
+/// CD / BC ∈ [2.24, 3.618]  (a very long terminal leg)
+/// AD / XA ∈ [1.55, 1.65]   (≈ 1.618 — the defining D completion)
+/// ```
+///
+/// Output is `+1.0` (bullish, D a swing low), `-1.0` (bearish, D a swing high),
+/// or `0.0`; never `None`. See `crates/wickra-core/src/indicators/crab.rs`.
+#[derive(Debug, Clone)]
+pub struct Crab {
+    swing: SwingTracker,
+    has_emitted: bool,
+}
+
+impl Crab {
+    /// Construct a new Crab detector.
+    pub const fn new() -> Self {
+        Self {
+            swing: SwingTracker::new(SWING_THRESHOLD, 5),
+            has_emitted: false,
+        }
+    }
+}
+
+impl Default for Crab {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+impl Indicator for Crab {
+    type Input = Candle;
+    type Output = f64;
+
+    fn update(&mut self, candle: Candle) -> Option<f64> {
+        self.has_emitted = true;
+        if !self.swing.update(candle) {
+            return Some(0.0);
+        }
+        let pivots = self.swing.pivots();
+        if pivots.len() < 5 {
+            return Some(0.0);
+        }
+        let p = xabcd(pivots);
+        let xa = (p.a - p.x).abs();
+        let ab = (p.b - p.a).abs();
+        let bc = (p.c - p.b).abs();
+        let cd = (p.d - p.c).abs();
+        let ad = (p.d - p.a).abs();
+        let matched = ratios_in(&[
+            (ab / xa, 0.382, 0.618),
+            (bc / ab, 0.382, 0.886),
+            (cd / bc, 2.24, 3.618),
+            (ad / xa, 1.55, 1.65),
+        ]);
+        if matched {
+            return Some(if p.bullish { 1.0 } else { -1.0 });
+        }
+        Some(0.0)
+    }
+
+    fn reset(&mut self) {
+        self.swing.reset();
+        self.has_emitted = false;
+    }
+
+    fn warmup_period(&self) -> usize {
+        6
+    }
+
+    fn is_ready(&self) -> bool {
+        self.has_emitted
+    }
+
+    fn name(&self) -> &'static str {
+        "Crab"
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::indicators::pattern_swing::candles_for_pivots;
+    use crate::traits::BatchExt;
+
+    fn run(pivots: &[f64]) -> Vec<f64> {
+        let mut indicator = Crab::new();
+        candles_for_pivots(pivots)
+            .into_iter()
+            .map(|c| indicator.update(c).unwrap())
+            .collect()
+    }
+
+    #[test]
+    fn accessors_and_metadata() {
+        let indicator = Crab::new();
+        assert_eq!(indicator.name(), "Crab");
+        assert_eq!(indicator.warmup_period(), 6);
+        assert!(!indicator.is_ready());
+        assert!(!Crab::default().is_ready());
+    }
+
+    #[test]
+    fn bullish_crab_is_plus_one() {
+        let out = run(&[150.0, 100.0, 140.0, 120.0, 137.5, 75.3]);
+        assert_eq!(*out.last().unwrap(), 1.0);
+        assert!(out[..out.len() - 1].iter().all(|&x| x == 0.0));
+    }
+
+    #[test]
+    fn bearish_crab_is_minus_one() {
+        let out = run(&[150.0, 110.0, 130.0, 112.5, 174.7]);
+        assert_eq!(*out.last().unwrap(), -1.0);
+    }
+
+    #[test]
+    fn out_of_ratio_does_not_trigger() {
+        let out = run(&[150.0, 100.0, 140.0, 110.0, 135.0, 105.0]);
+        assert_eq!(*out.last().unwrap(), 0.0);
+    }
+
+    #[test]
+    fn reset_clears_state() {
+        let mut indicator = Crab::new();
+        for c in candles_for_pivots(&[150.0, 100.0, 140.0]) {
+            let _ = indicator.update(c);
+        }
+        indicator.reset();
+        assert!(!indicator.is_ready());
+        let c = Candle::new(99.5, 100.0, 99.5, 99.5, 1.0, 0).unwrap();
+        assert_eq!(indicator.update(c), Some(0.0));
+    }
+
+    #[test]
+    fn batch_equals_streaming() {
+        let candles = candles_for_pivots(&[150.0, 100.0, 140.0, 120.0, 137.5, 75.3]);
+        let mut a = Crab::new();
+        let mut b = Crab::new();
+        assert_eq!(
+            a.batch(&candles),
+            candles.iter().map(|x| b.update(*x)).collect::<Vec<_>>()
+        );
+    }
+}
@@ -0,0 +1,152 @@
+//! Cypher harmonic pattern.
+
+use crate::indicators::pattern_swing::{ratios_in, xabcd, SwingTracker, SWING_THRESHOLD};
+use crate::ohlcv::Candle;
+use crate::traits::Indicator;
+
+/// Cypher — a 5-point (X-A-B-C-D) harmonic pattern whose C leg is measured
+/// against XA (not AB) and whose D retraces the XC leg by `0.786`:
+///
+/// ```text
+/// AB / XA ∈ [0.382, 0.618]
+/// BC / XA ∈ [1.13, 1.414]  (C extends beyond A, measured on XA)
+/// CD / XC ∈ [0.74, 0.83]   (≈ 0.786 retracement of XC — the D completion)
+/// ```
+///
+/// Output is `+1.0` (bullish, D a swing low), `-1.0` (bearish, D a swing high),
+/// or `0.0`; never `None`. See `crates/wickra-core/src/indicators/cypher.rs`.
+#[derive(Debug, Clone)]
+pub struct Cypher {
+    swing: SwingTracker,
+    has_emitted: bool,
+}
+
+impl Cypher {
+    /// Construct a new Cypher detector.
+    pub const fn new() -> Self {
+        Self {
+            swing: SwingTracker::new(SWING_THRESHOLD, 5),
+            has_emitted: false,
+        }
+    }
+}
+
+impl Default for Cypher {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+impl Indicator for Cypher {
+    type Input = Candle;
+    type Output = f64;
+
+    fn update(&mut self, candle: Candle) -> Option<f64> {
+        self.has_emitted = true;
+        if !self.swing.update(candle) {
+            return Some(0.0);
+        }
+        let pivots = self.swing.pivots();
+        if pivots.len() < 5 {
+            return Some(0.0);
+        }
+        let p = xabcd(pivots);
+        let xa = (p.a - p.x).abs();
+        let ab = (p.b - p.a).abs();
+        let bc = (p.c - p.b).abs();
+        let xc = (p.c - p.x).abs();
+        let cd = (p.d - p.c).abs();
+        let matched = ratios_in(&[
+            (ab / xa, 0.382, 0.618),
+            (bc / xa, 1.13, 1.414),
+            (cd / xc, 0.74, 0.83),
+        ]);
+        if matched {
+            return Some(if p.bullish { 1.0 } else { -1.0 });
+        }
+        Some(0.0)
+    }
+
+    fn reset(&mut self) {
+        self.swing.reset();
+        self.has_emitted = false;
+    }
+
+    fn warmup_period(&self) -> usize {
+        6
+    }
+
+    fn is_ready(&self) -> bool {
+        self.has_emitted
+    }
+
+    fn name(&self) -> &'static str {
+        "Cypher"
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::indicators::pattern_swing::candles_for_pivots;
+    use crate::traits::BatchExt;
+
+    fn run(pivots: &[f64]) -> Vec<f64> {
+        let mut indicator = Cypher::new();
+        candles_for_pivots(pivots)
+            .into_iter()
+            .map(|c| indicator.update(c).unwrap())
+            .collect()
+    }
+
+    #[test]
+    fn accessors_and_metadata() {
+        let indicator = Cypher::new();
+        assert_eq!(indicator.name(), "Cypher");
+        assert_eq!(indicator.warmup_period(), 6);
+        assert!(!indicator.is_ready());
+        assert!(!Cypher::default().is_ready());
+    }
+
+    #[test]
+    fn bullish_cypher_is_plus_one() {
+        let out = run(&[150.0, 100.0, 140.0, 120.0, 168.0, 114.55]);
+        assert_eq!(*out.last().unwrap(), 1.0);
+        assert!(out[..out.len() - 1].iter().all(|&x| x == 0.0));
+    }
+
+    #[test]
+    fn bearish_cypher_is_minus_one() {
+        let out = run(&[150.0, 110.0, 130.0, 82.0, 135.45]);
+        assert_eq!(*out.last().unwrap(), -1.0);
+    }
+
+    #[test]
+    fn out_of_ratio_does_not_trigger() {
+        let out = run(&[150.0, 100.0, 140.0, 110.0, 135.0, 105.0]);
+        assert_eq!(*out.last().unwrap(), 0.0);
+    }
+
+    #[test]
+    fn reset_clears_state() {
+        let mut indicator = Cypher::new();
+        for c in candles_for_pivots(&[150.0, 100.0, 140.0]) {
+            let _ = indicator.update(c);
+        }
+        indicator.reset();
+        assert!(!indicator.is_ready());
+        let c = Candle::new(99.5, 100.0, 99.5, 99.5, 1.0, 0).unwrap();
+        assert_eq!(indicator.update(c), Some(0.0));
+    }
+
+    #[test]
+    fn batch_equals_streaming() {
+        let candles = candles_for_pivots(&[150.0, 100.0, 140.0, 120.0, 168.0, 114.55]);
+        let mut a = Cypher::new();
+        let mut b = Cypher::new();
+        assert_eq!(
+            a.batch(&candles),
+            candles.iter().map(|x| b.update(*x)).collect::<Vec<_>>()
+        );
+    }
+}
@@ -0,0 +1,157 @@
+//! Gartley harmonic pattern.
+
+use crate::indicators::pattern_swing::{ratios_in, xabcd, SwingTracker, SWING_THRESHOLD};
+use crate::ohlcv::Candle;
+use crate::traits::Indicator;
+
+/// Gartley — the classic 5-point (X-A-B-C-D) harmonic pattern, recognised from
+/// confirmed swing pivots when the legs fall inside the Gartley Fibonacci
+/// windows:
+///
+/// ```text
+/// AB / XA ∈ [0.55, 0.70]   (≈ 0.618 retracement of XA)
+/// BC / AB ∈ [0.382, 0.886]
+/// CD / BC ∈ [1.13, 1.618]
+/// AD / XA ∈ [0.74, 0.84]   (≈ 0.786 — the defining D completion)
+/// ```
+///
+/// Output is `+1.0` when the terminal point D is a swing low (bullish
+/// completion), `-1.0` when D is a swing high (bearish), and `0.0` otherwise;
+/// never `None`. See `crates/wickra-core/src/indicators/gartley.rs`.
+#[derive(Debug, Clone)]
+pub struct Gartley {
+    swing: SwingTracker,
+    has_emitted: bool,
+}
+
+impl Gartley {
+    /// Construct a new Gartley detector.
+    pub const fn new() -> Self {
+        Self {
+            swing: SwingTracker::new(SWING_THRESHOLD, 5),
+            has_emitted: false,
+        }
+    }
+}
+
+impl Default for Gartley {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+impl Indicator for Gartley {
+    type Input = Candle;
+    type Output = f64;
+
+    fn update(&mut self, candle: Candle) -> Option<f64> {
+        self.has_emitted = true;
+        if !self.swing.update(candle) {
+            return Some(0.0);
+        }
+        let pivots = self.swing.pivots();
+        if pivots.len() < 5 {
+            return Some(0.0);
+        }
+        let p = xabcd(pivots);
+        let xa = (p.a - p.x).abs();
+        let ab = (p.b - p.a).abs();
+        let bc = (p.c - p.b).abs();
+        let cd = (p.d - p.c).abs();
+        let ad = (p.d - p.a).abs();
+        let matched = ratios_in(&[
+            (ab / xa, 0.55, 0.70),
+            (bc / ab, 0.382, 0.886),
+            (cd / bc, 1.13, 1.618),
+            (ad / xa, 0.74, 0.84),
+        ]);
+        if matched {
+            return Some(if p.bullish { 1.0 } else { -1.0 });
+        }
+        Some(0.0)
+    }
+
+    fn reset(&mut self) {
+        self.swing.reset();
+        self.has_emitted = false;
+    }
+
+    fn warmup_period(&self) -> usize {
+        6
+    }
+
+    fn is_ready(&self) -> bool {
+        self.has_emitted
+    }
+
+    fn name(&self) -> &'static str {
+        "Gartley"
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::indicators::pattern_swing::candles_for_pivots;
+    use crate::traits::BatchExt;
+
+    fn run(pivots: &[f64]) -> Vec<f64> {
+        let mut indicator = Gartley::new();
+        candles_for_pivots(pivots)
+            .into_iter()
+            .map(|c| indicator.update(c).unwrap())
+            .collect()
+    }
+
+    #[test]
+    fn accessors_and_metadata() {
+        let indicator = Gartley::new();
+        assert_eq!(indicator.name(), "Gartley");
+        assert_eq!(indicator.warmup_period(), 6);
+        assert!(!indicator.is_ready());
+        assert!(!Gartley::default().is_ready());
+    }
+
+    #[test]
+    fn bullish_gartley_is_plus_one() {
+        let out = run(&[150.0, 100.0, 140.0, 115.3, 127.65, 108.56]);
+        assert_eq!(*out.last().unwrap(), 1.0);
+        assert!(out[..out.len() - 1].iter().all(|&x| x == 0.0));
+    }
+
+    #[test]
+    fn bearish_gartley_is_minus_one() {
+        let out = run(&[150.0, 110.0, 134.7, 122.35, 141.44]);
+        assert_eq!(*out.last().unwrap(), -1.0);
+    }
+
+    #[test]
+    fn out_of_ratio_does_not_trigger() {
+        // Five pivots but the D completion (AD/XA ≈ 0.25) is far from 0.786.
+        let out = run(&[150.0, 100.0, 140.0, 110.0, 135.0, 105.0]);
+        assert_eq!(*out.last().unwrap(), 0.0);
+    }
+
+    #[test]
+    fn reset_clears_state() {
+        let mut indicator = Gartley::new();
+        for c in candles_for_pivots(&[150.0, 100.0, 140.0]) {
+            let _ = indicator.update(c);
+        }
+        indicator.reset();
+        assert!(!indicator.is_ready());
+        let c = Candle::new(99.5, 100.0, 99.5, 99.5, 1.0, 0).unwrap();
+        assert_eq!(indicator.update(c), Some(0.0));
+    }
+
+    #[test]
+    fn batch_equals_streaming() {
+        let candles = candles_for_pivots(&[150.0, 100.0, 140.0, 115.3, 127.65, 108.56]);
+        let mut a = Gartley::new();
+        let mut b = Gartley::new();
+        assert_eq!(
+            a.batch(&candles),
+            candles.iter().map(|x| b.update(*x)).collect::<Vec<_>>()
+        );
+    }
+}
@@ -10,6 +10,7 @@
 pub(crate) mod pattern_swing;

 mod abandoned_baby;
+mod abcd;
 mod absolute_breadth_index;
 mod acceleration_bands;
 mod accelerator_oscillator;
@@ -40,6 +41,7 @@ mod avg_price;
 mod awesome_oscillator;
 mod awesome_oscillator_histogram;
 mod balance_of_power;
+mod bat;
 mod belt_hold;
 mod beta;
 mod beta_neutral_spread;
@@ -48,6 +50,7 @@ mod bollinger_bandwidth;
 mod breadth_thrust;
 mod breakaway;
 mod bullish_percent_index;
+mod butterfly;
 mod calendar_spread;
 mod calmar_ratio;
 mod camarilla_pivots;
@@ -70,10 +73,12 @@ mod conditional_value_at_risk;
 mod connors_rsi;
 mod coppock;
 mod counterattack;
+mod crab;
 mod cumulative_volume_index;
 mod cup_and_handle;
 mod cvd;
 mod cybernetic_cycle;
+mod cypher;
 mod day_of_week_profile;
 mod decycler;
 mod decycler_oscillator;
@@ -119,6 +124,7 @@ mod funding_rate_zscore;
 mod gain_loss_ratio;
 mod gap_side_by_side_white;
 mod garman_klass;
+mod gartley;
 mod granger_causality;
 mod gravestone_doji;
 mod hammer;
@@ -262,6 +268,7 @@ mod separating_lines;
 mod session_high_low;
 mod session_range;
 mod session_vwap;
+mod shark;
 mod sharpe_ratio;
 mod shooting_star;
 mod short_line;
@@ -306,6 +313,7 @@ mod td_sequential;
 mod td_setup;
 mod tema;
 mod term_structure_basis;
+mod three_drives;
 mod three_inside;
 mod three_line_strike;
 mod three_outside;
@@ -369,6 +377,7 @@ mod zig_zag;
 mod zlema;

 pub use abandoned_baby::AbandonedBaby;
+pub use abcd::Abcd;
 pub use absolute_breadth_index::AbsoluteBreadthIndex;
 pub use acceleration_bands::{AccelerationBands, AccelerationBandsOutput};
 pub use accelerator_oscillator::AcceleratorOscillator;
@@ -399,6 +408,7 @@ pub use avg_price::AvgPrice;
 pub use awesome_oscillator::AwesomeOscillator;
 pub use awesome_oscillator_histogram::AwesomeOscillatorHistogram;
 pub use balance_of_power::BalanceOfPower;
+pub use bat::Bat;
 pub use belt_hold::BeltHold;
 pub use beta::Beta;
 pub use beta_neutral_spread::BetaNeutralSpread;
@@ -407,6 +417,7 @@ pub use bollinger_bandwidth::BollingerBandwidth;
 pub use breadth_thrust::BreadthThrust;
 pub use breakaway::Breakaway;
 pub use bullish_percent_index::BullishPercentIndex;
+pub use butterfly::Butterfly;
 pub use calendar_spread::CalendarSpread;
 pub use calmar_ratio::CalmarRatio;
 pub use camarilla_pivots::{Camarilla, CamarillaPivotsOutput};
@@ -429,10 +440,12 @@ pub use conditional_value_at_risk::ConditionalValueAtRisk;
 pub use connors_rsi::ConnorsRsi;
 pub use coppock::Coppock;
 pub use counterattack::Counterattack;
+pub use crab::Crab;
 pub use cumulative_volume_index::CumulativeVolumeIndex;
 pub use cup_and_handle::CupAndHandle;
 pub use cvd::CumulativeVolumeDelta;
 pub use cybernetic_cycle::CyberneticCycle;
+pub use cypher::Cypher;
 pub use day_of_week_profile::{DayOfWeekProfile, DayOfWeekProfileOutput};
 pub use decycler::Decycler;
 pub use decycler_oscillator::DecyclerOscillator;
@@ -478,6 +491,7 @@ pub use funding_rate_zscore::FundingRateZScore;
 pub use gain_loss_ratio::GainLossRatio;
 pub use gap_side_by_side_white::GapSideBySideWhite;
 pub use garman_klass::GarmanKlassVolatility;
+pub use gartley::Gartley;
 pub use granger_causality::GrangerCausality;
 pub use gravestone_doji::GravestoneDoji;
 pub use hammer::Hammer;
@@ -621,6 +635,7 @@ pub use separating_lines::SeparatingLines;
 pub use session_high_low::{SessionHighLow, SessionHighLowOutput};
 pub use session_range::{SessionRange, SessionRangeOutput};
 pub use session_vwap::SessionVwap;
+pub use shark::Shark;
 pub use sharpe_ratio::SharpeRatio;
 pub use shooting_star::ShootingStar;
 pub use short_line::ShortLine;
@@ -665,6 +680,7 @@ pub use td_sequential::{TdSequential, TdSequentialOutput};
 pub use td_setup::TdSetup;
 pub use tema::Tema;
 pub use term_structure_basis::TermStructureBasis;
+pub use three_drives::ThreeDrives;
 pub use three_inside::ThreeInside;
 pub use three_line_strike::ThreeLineStrike;
 pub use three_outside::ThreeOutside;
@@ -1193,6 +1209,19 @@ pub const FAMILIES: &[(&str, &[&str])] = &[
            "CupAndHandle",
        ],
    ),
+    (
+        "Harmonic Patterns",
+        &[
+            "Abcd",
+            "Gartley",
+            "Butterfly",
+            "Bat",
+            "Crab",
+            "Shark",
+            "Cypher",
+            "ThreeDrives",
+        ],
+    ),
 ];

 #[cfg(test)]
@@ -1221,6 +1250,6 @@ mod family_tests {
        // the actual indicator count is the early-warning signal that an
        // indicator was added without being assigned a family.
        let total: usize = FAMILIES.iter().map(|(_, ns)| ns.len()).sum();
-        assert_eq!(total, 359, "FAMILIES total drifted from indicator count");
+        assert_eq!(total, 367, "FAMILIES total drifted from indicator count");
    }
 }
@@ -191,6 +191,47 @@ pub(crate) fn approx_equal(a: f64, b: f64, tol: f64) -> bool {
    (a - b).abs() <= tol * scale
 }

+/// The five most recent pivots interpreted as the X-A-B-C-D points of a harmonic
+/// pattern, with the terminal direction. The slice must hold at least five
+/// pivots. Each detector derives the leg lengths and Fibonacci ratios it needs
+/// from these five prices.
+#[derive(Debug, Clone, Copy)]
+pub(crate) struct Xabcd {
+    pub x: f64,
+    pub a: f64,
+    pub b: f64,
+    pub c: f64,
+    pub d: f64,
+    /// `true` when the terminal point D is a swing low (a bullish, buy-side
+    /// completion); `false` when D is a swing high (bearish).
+    pub bullish: bool,
+}
+
+/// Read the last five pivots as an [`Xabcd`]. Pivots are guaranteed nonzero-leg
+/// (the swing tracker only confirms moves of at least the threshold), so the
+/// leg-ratio divisions in the detectors never divide by zero.
+pub(crate) fn xabcd(pivots: &[Pivot]) -> Xabcd {
+    let n = pivots.len();
+    Xabcd {
+        x: pivots[n - 5].price,
+        a: pivots[n - 4].price,
+        b: pivots[n - 3].price,
+        c: pivots[n - 2].price,
+        d: pivots[n - 1].price,
+        bullish: pivots[n - 1].direction < 0.0,
+    }
+}
+
+/// `true` when every `(value, low, high)` triple satisfies `low <= value <= high`.
+/// Harmonic detectors express their Fibonacci windows as a list of these triples;
+/// evaluating them in one expression keeps the per-triple comparison on a single
+/// line (no multi-line `&&` coverage gaps).
+pub(crate) fn ratios_in(checks: &[(f64, f64, f64)]) -> bool {
+    checks
+        .iter()
+        .all(|&(value, low, high)| value >= low && value <= high)
+}
+
 /// Build a candle sequence that drives a `SwingTracker` (or any detector built
 /// on one) to confirm exactly the given alternating pivot prices, in order.
 ///
@@ -378,6 +419,49 @@ mod tests {
        assert_eq!(recent_legs(&ending_low), (120.0, 110.0, 100.0, 99.0));
    }

+    #[test]
+    fn xabcd_reads_last_five_pivots_and_direction() {
+        let pivots = [
+            Pivot {
+                price: 50.0,
+                direction: 1.0,
+            },
+            Pivot {
+                price: 100.0,
+                direction: -1.0,
+            }, // X
+            Pivot {
+                price: 140.0,
+                direction: 1.0,
+            }, // A
+            Pivot {
+                price: 115.0,
+                direction: -1.0,
+            }, // B
+            Pivot {
+                price: 128.0,
+                direction: 1.0,
+            }, // C
+            Pivot {
+                price: 108.0,
+                direction: -1.0,
+            }, // D (low → bullish)
+        ];
+        let p = xabcd(&pivots);
+        assert_eq!(
+            (p.x, p.a, p.b, p.c, p.d),
+            (100.0, 140.0, 115.0, 128.0, 108.0)
+        );
+        assert!(p.bullish);
+    }
+
+    #[test]
+    fn ratios_in_checks_every_window() {
+        assert!(ratios_in(&[(0.6, 0.5, 0.7), (1.5, 1.0, 2.0)]));
+        assert!(!ratios_in(&[(0.6, 0.5, 0.7), (3.0, 1.0, 2.0)])); // second out of range
+        assert!(!ratios_in(&[(0.4, 0.5, 0.7)])); // below the window
+    }
+
    #[test]
    fn candles_for_pivots_realizes_the_requested_swings() {
        let want = [120.0, 100.0, 125.0, 95.0];
@@ -0,0 +1,155 @@
+//! Shark harmonic pattern.
+
+use crate::indicators::pattern_swing::{ratios_in, xabcd, SwingTracker, SWING_THRESHOLD};
+use crate::ohlcv::Candle;
+use crate::traits::Indicator;
+
+/// Shark — a 5-point (X-A-B-C-D) harmonic pattern characterised by an
+/// **expansion** leg (AB longer than XA) and a `0.886`–`1.13` D completion:
+///
+/// ```text
+/// AB / XA ∈ [1.13, 1.618]  (expansion — B overshoots X)
+/// BC / AB ∈ [1.618, 2.24]
+/// CD / BC ∈ [0.382, 0.886]
+/// AD / XA ∈ [0.886, 1.13]  (the defining D completion near A)
+/// ```
+///
+/// This is the 5-point reading of the Shark; output is `+1.0` (bullish, D a
+/// swing low), `-1.0` (bearish, D a swing high), or `0.0`; never `None`. See
+/// `crates/wickra-core/src/indicators/shark.rs`.
+#[derive(Debug, Clone)]
+pub struct Shark {
+    swing: SwingTracker,
+    has_emitted: bool,
+}
+
+impl Shark {
+    /// Construct a new Shark detector.
+    pub const fn new() -> Self {
+        Self {
+            swing: SwingTracker::new(SWING_THRESHOLD, 5),
+            has_emitted: false,
+        }
+    }
+}
+
+impl Default for Shark {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+impl Indicator for Shark {
+    type Input = Candle;
+    type Output = f64;
+
+    fn update(&mut self, candle: Candle) -> Option<f64> {
+        self.has_emitted = true;
+        if !self.swing.update(candle) {
+            return Some(0.0);
+        }
+        let pivots = self.swing.pivots();
+        if pivots.len() < 5 {
+            return Some(0.0);
+        }
+        let p = xabcd(pivots);
+        let xa = (p.a - p.x).abs();
+        let ab = (p.b - p.a).abs();
+        let bc = (p.c - p.b).abs();
+        let cd = (p.d - p.c).abs();
+        let ad = (p.d - p.a).abs();
+        let matched = ratios_in(&[
+            (ab / xa, 1.13, 1.618),
+            (bc / ab, 1.618, 2.24),
+            (cd / bc, 0.382, 0.886),
+            (ad / xa, 0.886, 1.13),
+        ]);
+        if matched {
+            return Some(if p.bullish { 1.0 } else { -1.0 });
+        }
+        Some(0.0)
+    }
+
+    fn reset(&mut self) {
+        self.swing.reset();
+        self.has_emitted = false;
+    }
+
+    fn warmup_period(&self) -> usize {
+        6
+    }
+
+    fn is_ready(&self) -> bool {
+        self.has_emitted
+    }
+
+    fn name(&self) -> &'static str {
+        "Shark"
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::indicators::pattern_swing::candles_for_pivots;
+    use crate::traits::BatchExt;
+
+    fn run(pivots: &[f64]) -> Vec<f64> {
+        let mut indicator = Shark::new();
+        candles_for_pivots(pivots)
+            .into_iter()
+            .map(|c| indicator.update(c).unwrap())
+            .collect()
+    }
+
+    #[test]
+    fn accessors_and_metadata() {
+        let indicator = Shark::new();
+        assert_eq!(indicator.name(), "Shark");
+        assert_eq!(indicator.warmup_period(), 6);
+        assert!(!indicator.is_ready());
+        assert!(!Shark::default().is_ready());
+    }
+
+    #[test]
+    fn bullish_shark_is_plus_one() {
+        let out = run(&[150.0, 100.0, 140.0, 88.0, 186.8, 100.0]);
+        assert_eq!(*out.last().unwrap(), 1.0);
+        assert!(out[..out.len() - 1].iter().all(|&x| x == 0.0));
+    }
+
+    #[test]
+    fn bearish_shark_is_minus_one() {
+        let out = run(&[150.0, 110.0, 162.0, 60.2, 150.0]);
+        assert_eq!(*out.last().unwrap(), -1.0);
+    }
+
+    #[test]
+    fn out_of_ratio_does_not_trigger() {
+        let out = run(&[150.0, 100.0, 140.0, 110.0, 135.0, 105.0]);
+        assert_eq!(*out.last().unwrap(), 0.0);
+    }
+
+    #[test]
+    fn reset_clears_state() {
+        let mut indicator = Shark::new();
+        for c in candles_for_pivots(&[150.0, 100.0, 140.0]) {
+            let _ = indicator.update(c);
+        }
+        indicator.reset();
+        assert!(!indicator.is_ready());
+        let c = Candle::new(99.5, 100.0, 99.5, 99.5, 1.0, 0).unwrap();
+        assert_eq!(indicator.update(c), Some(0.0));
+    }
+
+    #[test]
+    fn batch_equals_streaming() {
+        let candles = candles_for_pivots(&[150.0, 100.0, 140.0, 88.0, 186.8, 100.0]);
+        let mut a = Shark::new();
+        let mut b = Shark::new();
+        assert_eq!(
+            a.batch(&candles),
+            candles.iter().map(|x| b.update(*x)).collect::<Vec<_>>()
+        );
+    }
+}
@@ -0,0 +1,155 @@
+//! Three Drives harmonic pattern.
+
+use crate::indicators::pattern_swing::{
+    approx_equal, ratios_in, xabcd, SwingTracker, SWING_THRESHOLD,
+};
+use crate::ohlcv::Candle;
+use crate::traits::Indicator;
+
+/// Three Drives — a symmetric harmonic pattern of two visible drives separated
+/// by two retracements, read from the last five pivots `X-A-B-C-D` (the two
+/// drive legs are `A→B` and `C→D`):
+///
+/// ```text
+/// AB / XA ∈ [1.13, 1.75]   (drive 1 extends the prior retracement)
+/// CD / BC ∈ [1.13, 1.75]   (drive 2 extends symmetrically)
+/// AB ≈ CD (within 20%)      (the two drives are similar in size)
+/// XA ≈ BC (within 30%)      (the two retracements are similar)
+/// ```
+///
+/// Output is `+1.0` (bullish, terminal D a swing low — drives down), `-1.0`
+/// (bearish, drives up), or `0.0`; never `None`. See
+/// `crates/wickra-core/src/indicators/three_drives.rs`.
+#[derive(Debug, Clone)]
+pub struct ThreeDrives {
+    swing: SwingTracker,
+    has_emitted: bool,
+}
+
+impl ThreeDrives {
+    /// Construct a new Three Drives detector.
+    pub const fn new() -> Self {
+        Self {
+            swing: SwingTracker::new(SWING_THRESHOLD, 5),
+            has_emitted: false,
+        }
+    }
+}
+
+impl Default for ThreeDrives {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+impl Indicator for ThreeDrives {
+    type Input = Candle;
+    type Output = f64;
+
+    fn update(&mut self, candle: Candle) -> Option<f64> {
+        self.has_emitted = true;
+        if !self.swing.update(candle) {
+            return Some(0.0);
+        }
+        let pivots = self.swing.pivots();
+        if pivots.len() < 5 {
+            return Some(0.0);
+        }
+        let p = xabcd(pivots);
+        let xa = (p.a - p.x).abs();
+        let ab = (p.b - p.a).abs();
+        let bc = (p.c - p.b).abs();
+        let cd = (p.d - p.c).abs();
+        let extensions = ratios_in(&[(ab / xa, 1.13, 1.75), (cd / bc, 1.13, 1.75)]);
+        let symmetric = approx_equal(ab, cd, 0.20) && approx_equal(xa, bc, 0.30);
+        if extensions && symmetric {
+            return Some(if p.bullish { 1.0 } else { -1.0 });
+        }
+        Some(0.0)
+    }
+
+    fn reset(&mut self) {
+        self.swing.reset();
+        self.has_emitted = false;
+    }
+
+    fn warmup_period(&self) -> usize {
+        6
+    }
+
+    fn is_ready(&self) -> bool {
+        self.has_emitted
+    }
+
+    fn name(&self) -> &'static str {
+        "ThreeDrives"
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::indicators::pattern_swing::candles_for_pivots;
+    use crate::traits::BatchExt;
+
+    fn run(pivots: &[f64]) -> Vec<f64> {
+        let mut indicator = ThreeDrives::new();
+        candles_for_pivots(pivots)
+            .into_iter()
+            .map(|c| indicator.update(c).unwrap())
+            .collect()
+    }
+
+    #[test]
+    fn accessors_and_metadata() {
+        let indicator = ThreeDrives::new();
+        assert_eq!(indicator.name(), "ThreeDrives");
+        assert_eq!(indicator.warmup_period(), 6);
+        assert!(!indicator.is_ready());
+        assert!(!ThreeDrives::default().is_ready());
+    }
+
+    #[test]
+    fn bearish_three_drives_is_minus_one() {
+        // Three rising drives (120, 128, 136) → bearish exhaustion.
+        let out = run(&[120.0, 100.0, 128.0, 108.0, 136.0]);
+        assert_eq!(*out.last().unwrap(), -1.0);
+        assert!(out[..out.len() - 1].iter().all(|&x| x == 0.0));
+    }
+
+    #[test]
+    fn bullish_three_drives_is_plus_one() {
+        // Three falling drives → bullish exhaustion.
+        let out = run(&[150.0, 120.0, 140.0, 112.0, 132.0, 104.0]);
+        assert_eq!(*out.last().unwrap(), 1.0);
+    }
+
+    #[test]
+    fn asymmetric_drives_do_not_trigger() {
+        let out = run(&[150.0, 100.0, 140.0, 110.0, 135.0, 105.0]);
+        assert_eq!(*out.last().unwrap(), 0.0);
+    }
+
+    #[test]
+    fn reset_clears_state() {
+        let mut indicator = ThreeDrives::new();
+        for c in candles_for_pivots(&[120.0, 100.0, 128.0]) {
+            let _ = indicator.update(c);
+        }
+        indicator.reset();
+        assert!(!indicator.is_ready());
+        let c = Candle::new(99.5, 100.0, 99.5, 99.5, 1.0, 0).unwrap();
+        assert_eq!(indicator.update(c), Some(0.0));
+    }
+
+    #[test]
+    fn batch_equals_streaming() {
+        let candles = candles_for_pivots(&[120.0, 100.0, 128.0, 108.0, 136.0]);
+        let mut a = ThreeDrives::new();
+        let mut b = ThreeDrives::new();
+        assert_eq!(
+            a.batch(&candles),
+            candles.iter().map(|x| b.update(*x)).collect::<Vec<_>>()
+        );
+    }
+}
@@ -56,29 +56,30 @@ pub use cross_section::{CrossSection, Member};
 pub use derivatives::DerivativesTick;
 pub use error::{Error, Result};
 pub use indicators::{
-    AbandonedBaby, AbsoluteBreadthIndex, AccelerationBands, AccelerationBandsOutput,
+    AbandonedBaby, Abcd, AbsoluteBreadthIndex, AccelerationBands, AccelerationBandsOutput,
    AcceleratorOscillator, AdOscillator, AdVolumeLine, AdaptiveCycle, Adl, AdvanceBlock,
    AdvanceDecline, AdvanceDeclineRatio, Adx, AdxOutput, Adxr, Alligator, AlligatorOutput, Alma,
    Alpha, AnchoredRsi, AnchoredVwap, Apo, Aroon, AroonOscillator, AroonOutput, Atr, AtrBands,
    AtrBandsOutput, AtrTrailingStop, Autocorrelation, AverageDailyRange, AverageDrawdown, AvgPrice,
-    AwesomeOscillator, AwesomeOscillatorHistogram, BalanceOfPower, BeltHold, Beta,
+    AwesomeOscillator, AwesomeOscillatorHistogram, BalanceOfPower, Bat, BeltHold, Beta,
    BetaNeutralSpread, BollingerBands, BollingerBandwidth, BollingerOutput, BreadthThrust,
-    Breakaway, BullishPercentIndex, CalendarSpread, CalmarRatio, Camarilla, CamarillaPivotsOutput,
-    Cci, CenterOfGravity, Cfo, ChaikinMoneyFlow, ChaikinOscillator, ChaikinVolatility,
-    ChandeKrollStop, ChandeKrollStopOutput, ChandelierExit, ChandelierExitOutput, ChoppinessIndex,
-    ClassicPivots, ClassicPivotsOutput, ClosingMarubozu, Cmo, CoefficientOfVariation,
-    Cointegration, CointegrationOutput, ConcealingBabySwallow, ConditionalValueAtRisk, ConnorsRsi,
-    Coppock, Counterattack, CumulativeVolumeDelta, CumulativeVolumeIndex, CupAndHandle,
-    CyberneticCycle, DayOfWeekProfile, DayOfWeekProfileOutput, Decycler, DecyclerOscillator, Dema,
-    DemandIndex, DemarkPivots, DemarkPivotsOutput, DepthSlope, DetrendedStdDev, DistanceSsd, Doji,
-    DojiStar, Donchian, DonchianOutput, DonchianStop, DonchianStopOutput, DoubleBollinger,
-    DoubleBollingerOutput, DoubleTopBottom, DownsideGapThreeMethods, Dpo, DragonflyDoji,
-    DrawdownDuration, Dx, EaseOfMovement, EffectiveSpread, EhlersStochastic, ElderImpulse, Ema,
+    Breakaway, BullishPercentIndex, Butterfly, CalendarSpread, CalmarRatio, Camarilla,
+    CamarillaPivotsOutput, Cci, CenterOfGravity, Cfo, ChaikinMoneyFlow, ChaikinOscillator,
+    ChaikinVolatility, ChandeKrollStop, ChandeKrollStopOutput, ChandelierExit,
+    ChandelierExitOutput, ChoppinessIndex, ClassicPivots, ClassicPivotsOutput, ClosingMarubozu,
+    Cmo, CoefficientOfVariation, Cointegration, CointegrationOutput, ConcealingBabySwallow,
+    ConditionalValueAtRisk, ConnorsRsi, Coppock, Counterattack, Crab, CumulativeVolumeDelta,
+    CumulativeVolumeIndex, CupAndHandle, CyberneticCycle, Cypher, DayOfWeekProfile,
+    DayOfWeekProfileOutput, Decycler, DecyclerOscillator, Dema, DemandIndex, DemarkPivots,
+    DemarkPivotsOutput, DepthSlope, DetrendedStdDev, DistanceSsd, Doji, DojiStar, Donchian,
+    DonchianOutput, DonchianStop, DonchianStopOutput, DoubleBollinger, DoubleBollingerOutput,
+    DoubleTopBottom, DownsideGapThreeMethods, Dpo, DragonflyDoji, DrawdownDuration, Dx,
+    EaseOfMovement, EffectiveSpread, EhlersStochastic, ElderImpulse, Ema,
    EmpiricalModeDecomposition, Engulfing, EveningDojiStar, Evwma, FallingThreeMethods, Fama,
    FibonacciPivots, FibonacciPivotsOutput, FisherTransform, FlagPennant, Footprint,
    FootprintOutput, ForceIndex, FractalChaosBands, FractalChaosBandsOutput, Frama, FundingBasis,
    FundingRate, FundingRateMean, FundingRateZScore, GainLossRatio, GapSideBySideWhite,
-    GarmanKlassVolatility, GrangerCausality, GravestoneDoji, Hammer, HangingMan, Harami,
+    GarmanKlassVolatility, Gartley, GrangerCausality, GravestoneDoji, Hammer, HangingMan, Harami,
    HeadAndShoulders, HeikinAshi, HeikinAshiOutput, HiLoActivator, HighLowIndex, HighWave, Hikkake,
    HikkakeModified, HilbertDominantCycle, HistoricalVolatility, Hma, HomingPigeon, HtDcPhase,
    HtPhasor, HtPhasorOutput, HtTrendMode, HurstChannel, HurstChannelOutput, HurstExponent,
@@ -105,7 +106,7 @@ pub use indicators::{
    RenkoTrailingStop, RickshawMan, RisingThreeMethods, Roc, Rocp, Rocr, Rocr100,
    RogersSatchellVolatility, RollingCorrelation, RollingCovariance, RollingVwap, RoofingFilter,
    Rsi, Rvi, RviVolatility, Rwi, RwiOutput, SarExt, SeasonalZScore, SeparatingLines,
-    SessionHighLow, SessionHighLowOutput, SessionRange, SessionRangeOutput, SessionVwap,
+    SessionHighLow, SessionHighLowOutput, SessionRange, SessionRangeOutput, SessionVwap, Shark,
    SharpeRatio, ShootingStar, ShortLine, SignedVolume, SineWave, Skewness, Sma, Smi, Smma,
    SortinoRatio, SpearmanCorrelation, SpinningTop, SpreadBollingerBands,
    SpreadBollingerBandsOutput, SpreadHurst, StalledPattern, StandardError, StandardErrorBands,
@@ -114,9 +115,9 @@ pub use indicators::{
    SuperTrendOutput, TakerBuySellRatio, Takuri, TasukiGap, TdCombo, TdCountdown, TdDeMarker,
    TdDifferential, TdLines, TdLinesOutput, TdOpen, TdPressure, TdRangeProjection,
    TdRangeProjectionOutput, TdRei, TdRiskLevel, TdRiskLevelOutput, TdSequential,
-    TdSequentialOutput, TdSetup, Tema, TermStructureBasis, ThreeInside, ThreeLineStrike,
-    ThreeOutside, ThreeSoldiersOrCrows, ThreeStarsInSouth, Thrusting, TickIndex, Tii,
-    TimeOfDayReturnProfile, TimeOfDayReturnProfileOutput, TpoProfile, TpoProfileOutput,
+    TdSequentialOutput, TdSetup, Tema, TermStructureBasis, ThreeDrives, ThreeInside,
+    ThreeLineStrike, ThreeOutside, ThreeSoldiersOrCrows, ThreeStarsInSouth, Thrusting, TickIndex,
+    Tii, TimeOfDayReturnProfile, TimeOfDayReturnProfileOutput, TpoProfile, TpoProfileOutput,
    TradeImbalance, TreynorRatio, Triangle, Trima, Trin, TripleTopBottom, Trix, TrueRange, Tsf,
    Tsi, Tsv, TtmSqueeze, TtmSqueezeOutput, TurnOfMonth, Tweezer, TwoCrows, TypicalPrice,
    UlcerIndex, UltimateOscillator, UniqueThreeRiver, UpDownVolumeRatio, UpsideGapThreeMethods,