Provide sorting method for selecting proofs to swap

crates/cdk/examples/proof-selection.rs

@@ -6,7 +6,7 @@ use std::time::Duration;
 use cdk::amount::SplitTarget;
 use cdk::cdk_database::WalletMemoryDatabase;
 use cdk::nuts::{CurrencyUnit, MintQuoteState};
-use cdk::wallet::Wallet;
+use cdk::wallet::{SelectProofsOptions, Wallet};
 use cdk::Amount;
 use rand::Rng;
 use tokio::time::sleep;
@@ -51,7 +51,11 @@ async fn main() {
     let proofs = wallet.get_proofs().await.unwrap();
 
     let selected = wallet
-        .select_proofs_to_send(Amount::from(64), proofs, false)
+        .select_proofs(
+            Amount::from(64),
+            proofs,
+            SelectProofsOptions::default().include_fees(false),
+        )
         .await
         .unwrap();
 

crates/cdk/src/nuts/nut01/public_key.rs

@@ -92,6 +92,16 @@ impl PublicKey {
         SECP256K1.verify_schnorr(sig, &msg, &self.inner.x_only_public_key().0)?;
         Ok(())
     }
+
+    #[cfg(test)]
+    pub fn random() -> Self {
+        Self {
+            inner: secp256k1::PublicKey::from_secret_key(
+                &SECP256K1,
+                &secp256k1::SecretKey::new(&mut rand::thread_rng()),
+            ),
+        }
+    }
 }
 
 impl FromStr for PublicKey {

crates/cdk/src/nuts/nut02.rs

@@ -105,6 +105,14 @@ impl Id {
             id: bytes[1..].try_into()?,
         })
     }
+
+    #[cfg(test)]
+    pub fn random() -> Self {
+        Self {
+            version: KeySetVersion::Version00,
+            id: rand::random(),
+        }
+    }
 }
 
 impl TryFrom<Id> for u64 {

crates/cdk/src/wallet/melt.rs

@@ -11,7 +11,7 @@ use crate::{
     Amount, Error, Wallet,
 };
 
-use super::MeltQuote;
+use super::{proofs::SelectProofsOptions, MeltQuote};
 
 impl Wallet {
     /// Melt Quote
@@ -294,7 +294,11 @@ impl Wallet {
         let available_proofs = self.get_proofs().await?;
 
         let input_proofs = self
-            .select_proofs_to_swap(inputs_needed_amount, available_proofs)
+            .select_proofs(
+                inputs_needed_amount,
+                available_proofs,
+                SelectProofsOptions::default(),
+            )
             .await?;
 
         self.melt_proofs(quote_id, input_proofs).await

crates/cdk/src/wallet/mod.rs

@@ -36,6 +36,7 @@ pub mod types;
 pub mod util;
 
 pub use multi_mint_wallet::MultiMintWallet;
+pub use proofs::{ProofSelectionMethod, SelectProofsOptions};
 pub use types::{MeltQuote, MintQuote, SendKind};
 
 /// CDK Wallet