Add SpWallet

src/silentpayments.rs

@@ -1,12 +1,146 @@
-use std::collections::{HashMap, HashSet};
+use std::collections::HashMap;
 
 use anyhow::{Error, Result};
 use serde::{Deserialize, Serialize};
+use sp_client::bitcoin::absolute::Height;
+use sp_client::bitcoin::hex::DisplayHex;
+use sp_client::bitcoin::secp256k1::{PublicKey, SecretKey};
 use tsify::Tsify;
 
 use rand::{thread_rng, Rng};
-use sp_client::bitcoin::{Amount, OutPoint, Transaction};
+use sp_client::bitcoin::{Amount, OutPoint, Transaction, XOnlyPublicKey, TxOut};
-use sp_client::{OwnedOutput, Recipient, SilentPaymentUnsignedTransaction, SpClient};
+use sp_client::{FeeRate, OutputSpendStatus, OwnedOutput, Recipient, SilentPaymentUnsignedTransaction, SpClient};
+use sp_client::silentpayments::utils::receiving::calculate_ecdh_shared_secret;
+
+#[derive(Debug, Default, Deserialize, Serialize, Clone)]
+pub struct SpWallet {
+    sp_client: SpClient,
+    outputs: HashMap<OutPoint, OwnedOutput>,
+    birthday: u32,
+    last_scan: u32,
+}
+
+impl SpWallet {
+    pub fn new(sp_client: SpClient) -> Self {
+        Self {
+            sp_client,
+            ..Default::default()
+        }
+    }
+
+    pub fn get_sp_client(&self) -> &SpClient {
+        &self.sp_client
+    }
+
+    pub fn get_outputs(&self) -> &HashMap<OutPoint, OwnedOutput> {
+        &self.outputs
+    }
+
+    pub fn get_mut_outputs(&mut self) -> &mut HashMap<OutPoint, OwnedOutput> {
+        &mut self.outputs
+    }
+
+    pub fn get_unspent_outputs(&self) -> HashMap<OutPoint, OwnedOutput> {
+        self.outputs.iter()
+            .filter(|(_, output)| output.spend_status == OutputSpendStatus::Unspent)
+            .map(|(outpoint, output)| (*outpoint, output.clone()))
+            .collect()
+    }
+
+    pub fn get_balance(&self) -> Amount {
+        self.outputs.values()
+            .filter(|output| output.spend_status == OutputSpendStatus::Unspent)
+            .fold(Amount::ZERO, |acc, x| acc + x.amount)
+    }
+
+    pub fn get_birthday(&self) -> u32 {
+        self.birthday
+    }
+
+    pub fn set_birthday(&mut self, birthday: u32) {
+        self.birthday = birthday;
+    }
+
+    pub fn get_last_scan(&self) -> u32 {
+        self.last_scan
+    }
+
+    pub fn set_last_scan(&mut self, last_scan: u32) {
+        self.last_scan = last_scan;
+    }
+
+    pub fn update_with_transaction(&mut self, tx: &Transaction, public_tweak: &PublicKey, height: u32) -> Result<HashMap<OutPoint, OwnedOutput>> {
+        let receiver = &self.get_sp_client().sp_receiver;
+        let p2tr_outs: Vec<(usize, &TxOut)> = tx
+            .output
+            .iter()
+            .enumerate()
+            .filter(|(_, o)| o.script_pubkey.is_p2tr())
+            .collect();
+
+        if p2tr_outs.is_empty() {
+            return Err(Error::msg("No taproot outputs"))
+        }; // That should never happen since we have a tweak_data, but anyway
+
+        // Now we can just run sp_receiver on all the p2tr outputs
+        let xonlykeys: Result<Vec<XOnlyPublicKey>> = p2tr_outs
+            .iter()
+            .map(|(_, o)| {
+                XOnlyPublicKey::from_slice(&o.script_pubkey.as_bytes()[2..]).map_err(Error::new)
+            })
+            .collect();
+
+        let tweak_data = calculate_ecdh_shared_secret(public_tweak, &self.sp_client.get_scan_key());
+        let ours = receiver.scan_transaction(&tweak_data, xonlykeys?)?;
+
+        let txid = tx.txid();
+        let height = Height::from_consensus(height)?;
+        let mut res = HashMap::new();
+        for (label, map) in ours {
+            res.extend(p2tr_outs.iter().filter_map(|(i, o)| {
+                match XOnlyPublicKey::from_slice(&o.script_pubkey.as_bytes()[2..]) {
+                    Ok(key) => {
+                        if let Some(scalar) = map.get(&key) {
+                            match SecretKey::from_slice(&scalar.to_be_bytes()) {
+                                Ok(tweak) => {
+                                    let outpoint = OutPoint {
+                                        txid,
+                                        vout: *i as u32,
+                                    };
+                                    let label_str: Option<String>;
+                                    if let Some(l) = &label {
+                                        label_str =
+                                            Some(l.as_inner().to_be_bytes().to_lower_hex_string());
+                                    } else {
+                                        label_str = None;
+                                    }
+                                    return Some((
+                                        outpoint,
+                                        OwnedOutput {
+                                            blockheight: height,
+                                            tweak: tweak.secret_bytes(),
+                                            amount: o.value,
+                                            script: o.script_pubkey.clone(),
+                                            label: label_str,
+                                            spend_status: OutputSpendStatus::Unspent,
+                                        },
+                                    ));
+                                }
+                                Err(_) => {
+                                    return None;
+                                }
+                            }
+                        }
+                        None
+                    }
+                    Err(_) => None,
+                }
+            }));
+        }
+        self.get_mut_outputs().extend(res.clone());
+        Ok(res)
+    }
+}
 
 #[derive(Debug, Serialize, Deserialize, PartialEq, Tsify)]
 #[tsify(from_wasm_abi)]