From 5e3fd34d5dc3051057ea3d3d1dd2126a83c7c5ae Mon Sep 17 00:00:00 2001
From: Hunter Trujillo <cryptoquick@pm.me>
Date: Sun, 14 Jan 2024 10:38:02 -0700
Subject: [PATCH] Add segwit key derivation as a feature

---
 Cargo.lock          |  2 +-
 Cargo.toml          |  1 +
 src/bitcoin/keys.rs | 12 +++++++++++-
 src/constants.rs    |  7 +++++++
 4 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index f9597f0f..b3ab1932 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -659,7 +659,7 @@ dependencies = [
 
 [[package]]
 name = "bitmask-core"
-version = "0.7.0-beta.10"
+version = "0.7.0-beta.11"
 dependencies = [
  "amplify",
  "anyhow",
diff --git a/Cargo.toml b/Cargo.toml
index 94596af3..18bb118b 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -24,6 +24,7 @@ required-features = ["server"]
 all = []
 default = []
 web = []
+segwit = []
 server = ["tokio/full", "tower-http/cors"]
 
 [dependencies]
diff --git a/src/bitcoin/keys.rs b/src/bitcoin/keys.rs
index 3eafcb61..c7c1ec8d 100644
--- a/src/bitcoin/keys.rs
+++ b/src/bitcoin/keys.rs
@@ -1,12 +1,16 @@
 use std::str::FromStr;
 
+#[cfg(feature = "segwit")]
+use bdk::miniscript::Segwitv0;
+#[cfg(not(feature = "segwit"))]
+use bdk::miniscript::Tap;
 use bdk::{
     bitcoin::{
         secp256k1::Secp256k1,
         util::bip32::{ChildNumber, DerivationPath, ExtendedPrivKey, ExtendedPubKey, KeySource},
     },
     keys::{DerivableKey, DescriptorKey, DescriptorKey::Secret as SecretDesc, DescriptorSecretKey},
-    miniscript::{descriptor::DescriptorKeyParseError, Tap},
+    miniscript::descriptor::DescriptorKeyParseError,
 };
 use bip39::{Language, Mnemonic};
 use bitcoin::{KeyPair, Network};
@@ -70,10 +74,16 @@ fn get_descriptor(
     let deriv_descriptor = DerivationPath::from_str(path)?;
     let derived_xprv = &xprv.derive_priv(&secp, &deriv_descriptor)?;
     let origin: KeySource = (xprv.fingerprint(&secp), deriv_descriptor);
+    #[cfg(not(feature = "segwit"))]
     let derived_xprv_desc_key: DescriptorKey<Tap> = derived_xprv.into_descriptor_key(
         Some(origin),
         DerivationPath::default().child(ChildNumber::from_normal_idx(change)?),
     )?;
+    #[cfg(feature = "segwit")]
+    let derived_xprv_desc_key: DescriptorKey<Segwitv0> = derived_xprv.into_descriptor_key(
+        Some(origin),
+        DerivationPath::default().child(ChildNumber::from_normal_idx(change)?),
+    )?;
 
     if let SecretDesc(desc_seckey, _, _) = derived_xprv_desc_key {
         Ok(desc_seckey)
diff --git a/src/constants.rs b/src/constants.rs
index c9e593be..03b6b4a3 100644
--- a/src/constants.rs
+++ b/src/constants.rs
@@ -90,8 +90,15 @@ pub async fn get_udas_utxo() -> String {
 }
 
 // Descriptor strings
+#[cfg(not(feature = "segwit"))]
 pub const BTC_MAINNET_PATH: &str = "m/86h/0h/0h";
+#[cfg(not(feature = "segwit"))]
 pub const BTC_TESTNET_PATH: &str = "m/86h/1h/0h";
+#[cfg(feature = "segwit")]
+pub const BTC_MAINNET_PATH: &str = "m/84h/0h/0h";
+#[cfg(feature = "segwit")]
+pub const BTC_TESTNET_PATH: &str = "m/84h/1h/0h";
+
 pub static BTC_PATH: Lazy<RwLock<String>> = Lazy::new(|| {
     RwLock::new(if dot_env("BITCOIN_NETWORK") == "bitcoin" {
         BTC_MAINNET_PATH.to_owned()