From 9d39147e3068ac9f49a290c5c92eb2860004ec76 Mon Sep 17 00:00:00 2001
From: yancy <email@yancy.lol>
Date: Tue, 20 Feb 2024 11:04:40 +0100
Subject: [PATCH] wip: move to effective_value from rust-bitcoin

---
 Cargo.toml              | 10 +++++-----
 src/branch_and_bound.rs |  3 ++-
 src/lib.rs              | 15 ++++++++-------
 3 files changed, 15 insertions(+), 13 deletions(-)

diff --git a/Cargo.toml b/Cargo.toml
index ab7e9af..23c175f 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -15,7 +15,7 @@ keywords = ["crypto", "bitcoin"]
 readme = "README.md"
 
 [dependencies]
-bitcoin = { git="https://github.com/yancyribbens/rust-bitcoin", rev="2f109442e30d74fb7502e7fd1ce2075a67262cd5" }
+bitcoin = { git="https://github.com/yancyribbens/rust-bitcoin", rev="14e3bc" }
 rand = {version = "0.8.5", default-features = false, optional = true}
 
 [dev-dependencies]
@@ -24,10 +24,10 @@ rust-bitcoin-coin-selection = {path = ".", features = ["rand"]}
 rand = "0.8.5"
 
 [patch.crates-io]
-bitcoin_hashes = { git = "https://github.com/yancyribbens/rust-bitcoin", rev="2f109442e30d74fb7502e7fd1ce2075a67262cd5"  }
-bitcoin-io = { git = "https://github.com/yancyribbens/rust-bitcoin", rev="2f109442e30d74fb7502e7fd1ce2075a67262cd5" } 
-bitcoin-units = { git = "https://github.com/yancyribbens/rust-bitcoin", rev="2f109442e30d74fb7502e7fd1ce2075a67262cd5" }
-bitcoin-internals = { git = "https://github.com/yancyribbens/rust-bitcoin", rev="2f109442e30d74fb7502e7fd1ce2075a67262cd5" }
+bitcoin_hashes = { git = "https://github.com/yancyribbens/rust-bitcoin", rev="14e3bc" }
+bitcoin-io = { git = "https://github.com/yancyribbens/rust-bitcoin", rev="14e3bc" }
+bitcoin-units = { git = "https://github.com/yancyribbens/rust-bitcoin", rev="14e3bc" }
+bitcoin-internals = { git = "https://github.com/yancyribbens/rust-bitcoin", rev="14e3bc" }
 
 [[bench]]
 name = "coin_selection"
diff --git a/src/branch_and_bound.rs b/src/branch_and_bound.rs
index f9a9ffb..8923c65 100644
--- a/src/branch_and_bound.rs
+++ b/src/branch_and_bound.rs
@@ -9,6 +9,7 @@ use bitcoin::amount::CheckedSum;
 use bitcoin::Amount;
 use bitcoin::FeeRate;
 use bitcoin::SignedAmount;
+use bitcoin::blockdata::transaction::effective_value;
 
 /// Select coins bnb performs a depth first branch and bound search.  The search traverses a
 /// binary tree with a maximum depth n where n is the size of the UTXO pool to be searched.
@@ -159,7 +160,7 @@ pub fn select_coins_bnb(
     let mut w_utxos: Vec<(Amount, SignedAmount, &WeightedUtxo)> = weighted_utxos
         .iter()
         // calculate effective_value and waste for each w_utxo.
-        .map(|wu| (wu.effective_value(fee_rate), wu.waste(fee_rate, long_term_fee_rate), wu))
+        .map(|wu| (effective_value(fee_rate, wu.satisfaction_weight, wu.utxo.value), wu.waste(fee_rate, long_term_fee_rate), wu))
         // remove utxos that either had an error in the effective_value or waste calculation.
         .filter(|(eff_val, waste, _)| !eff_val.is_none() && !waste.is_none())
         // unwrap the option type since we know they are not None (see previous step).
diff --git a/src/lib.rs b/src/lib.rs
index ac78061..40f3822 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -27,7 +27,6 @@ use bitcoin::Weight;
 
 pub use crate::branch_and_bound::select_coins_bnb;
 use crate::single_random_draw::select_coins_srd;
-use bitcoin::blockdata::transaction::TxIn;
 use rand::thread_rng;
 
 // https://github.com/bitcoin/bitcoin/blob/f722a9bd132222d9d5cd503b5af25c905b205cdb/src/wallet/coinselection.h#L20
@@ -46,14 +45,16 @@ pub struct WeightedUtxo {
     pub utxo: TxOut,
 }
 
-impl WeightedUtxo {
-    fn effective_value(&self, fee_rate: FeeRate) -> Option<SignedAmount> {
-        let signed_input_fee = self.calculate_fee(fee_rate)?.to_signed().ok()?;
-        self.utxo.value.to_signed().ok()?.checked_sub(signed_input_fee)
-    }
+// Serialized length of a u32.
+const SEQUENCE_SIZE: u64 = 4;
+// The serialized lengths of txid and vout.
+const OUTPOINT_SIZE: u64 = 32 + 4;
+const TX_IN_BASE_WEIGHT: Weight =
+        Weight::from_vb_unwrap(OUTPOINT_SIZE + SEQUENCE_SIZE);
 
+impl WeightedUtxo {
     fn calculate_fee(&self, fee_rate: FeeRate) -> Option<Amount> {
-        let weight = self.satisfaction_weight.checked_add(TxIn::BASE_WEIGHT)?;
+        let weight = self.satisfaction_weight.checked_add(TX_IN_BASE_WEIGHT)?;
         fee_rate.checked_mul_by_weight(weight)
     }