POC

crates/chain/src/rusqlite_impl.rs

@@ -70,6 +70,25 @@ pub fn migrate_schema(
     Ok(())
 }
 
+/// Serde!
+pub struct SerdeImpl<T>(pub T);
+
+impl<T: serde_crate::de::DeserializeOwned> FromSql for SerdeImpl<T> {
+    fn column_result(value: ValueRef<'_>) -> FromSqlResult<Self> {
+        serde_json::from_str(value.as_str()?)
+            .map(SerdeImpl)
+            .map_err(from_sql_error)
+    }
+}
+
+impl<T: serde_crate::Serialize> ToSql for SerdeImpl<T> {
+    fn to_sql(&self) -> rusqlite::Result<ToSqlOutput<'_>> {
+        serde_json::to_string(&self.0)
+            .map(Into::into)
+            .map_err(to_sql_error)
+    }
+}
+
 impl FromSql for Impl<bitcoin::Txid> {
     fn column_result(value: ValueRef<'_>) -> FromSqlResult<Self> {
         bitcoin::Txid::from_str(value.as_str()?)

crates/wallet/src/types.rs

@@ -18,6 +18,25 @@ use bitcoin::{psbt, Weight};
 
 use serde::{Deserialize, Serialize};
 
+/// Trait that determines if a keychain variant is trusted.
+pub trait WalletKeychain {
+    const DEFAULT_CHANGE_VARIANT: Self;
+
+    /// Returns whether the keychain variant is trusted.
+    fn is_trusted_variant(&self) -> bool;
+}
+
+impl WalletKeychain for KeychainKind {
+    const DEFAULT_CHANGE_VARIANT: Self = KeychainKind::Internal;
+
+    fn is_trusted_variant(&self) -> bool {
+        match self {
+            KeychainKind::External => false,
+            KeychainKind::Internal => true,
+        }
+    }
+}
+
 /// Types of keychains
 #[derive(Serialize, Deserialize, Debug, Clone, Copy, PartialEq, Eq, Hash, Ord, PartialOrd)]
 pub enum KeychainKind {
@@ -50,13 +69,13 @@ impl AsRef<[u8]> for KeychainKind {
 ///
 /// [`Wallet`]: crate::Wallet
 #[derive(Serialize, Deserialize, Debug, Clone, PartialEq, Eq, Hash)]
-pub struct LocalOutput {
+pub struct LocalOutput<K> {
     /// Reference to a transaction output
     pub outpoint: OutPoint,
     /// Transaction output
     pub txout: TxOut,
     /// Type of keychain
-    pub keychain: KeychainKind,
+    pub keychain: K,
     /// Whether this UTXO is spent or not
     pub is_spent: bool,
     /// The derivation index for the script pubkey in the wallet
@@ -67,21 +86,21 @@ pub struct LocalOutput {
 
 /// A [`Utxo`] with its `satisfaction_weight`.
 #[derive(Debug, Clone, PartialEq, Eq)]
-pub struct WeightedUtxo {
+pub struct WeightedUtxo<K> {
     /// The weight of the witness data and `scriptSig` expressed in [weight units]. This is used to
     /// properly maintain the feerate when adding this input to a transaction during coin selection.
     ///
     /// [weight units]: https://en.bitcoin.it/wiki/Weight_units
     pub satisfaction_weight: Weight,
     /// The UTXO
-    pub utxo: Utxo,
+    pub utxo: Utxo<K>,
 }
 
 #[derive(Debug, Clone, PartialEq, Eq)]
 /// An unspent transaction output (UTXO).
-pub enum Utxo {
+pub enum Utxo<K> {
     /// A UTXO owned by the local wallet.
-    Local(LocalOutput),
+    Local(LocalOutput<K>),
     /// A UTXO owned by another wallet.
     Foreign {
         /// The location of the output.
@@ -94,7 +113,7 @@ pub enum Utxo {
     },
 }
 
-impl Utxo {
+impl<K> Utxo<K> {
     /// Get the location of the UTXO
     pub fn outpoint(&self) -> OutPoint {
         match &self {