transaction: implement effects summary (#4943)

## Describe your changes

References #4939

## Checklist before requesting a review

- [x] I have added guiding text to explain how a reviewer should test
these changes.

- [x] If this code contains consensus-breaking changes, I have added the
"consensus-breaking" label. Otherwise, I declare my belief that there
are not consensus-breaking changes, for the following reason:

---------

Signed-off-by: Erwan Or <[email protected]>
Co-authored-by: Lucas Meier <[email protected]>
Co-authored-by: Erwan Or <[email protected]>
Co-authored-by: Erwan Or <[email protected]>

crates/core/keys/src/address/view.rs

@@ -1,3 +1,5 @@
+use std::cmp::Ordering;
+
 use serde::{Deserialize, Serialize};
 
 use penumbra_proto::{penumbra::core::keys::v1 as pb, DomainType};
@@ -99,6 +101,76 @@ impl TryFrom<pb::AddressView> for AddressView {
     }
 }
 
+// Canonical ordering for serialization
+impl PartialOrd for AddressView {
+    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
+        use AddressView::*;
+        // Opaque < Decoded
+        match (self, other) {
+            (Opaque { .. }, Decoded { .. }) => Some(Ordering::Less),
+            (Decoded { .. }, Opaque { .. }) => Some(Ordering::Greater),
+            (Opaque { address: a1 }, Opaque { address: a2 }) => a1.partial_cmp(a2),
+            (
+                Decoded {
+                    address: a1,
+                    index: i1,
+                    wallet_id: w1,
+                },
+                Decoded {
+                    address: a2,
+                    index: i2,
+                    wallet_id: w2,
+                },
+            ) => (a1, i1, w1).partial_cmp(&(a2, i2, w2)),
+        }
+    }
+}
+
+impl Ord for AddressView {
+    fn cmp(&self, other: &Self) -> Ordering {
+        // Opaque < Decoded
+        match (self, other) {
+            (AddressView::Opaque { address: a1 }, AddressView::Opaque { address: a2 }) => {
+                a1.cmp(a2)
+            }
+            (
+                AddressView::Decoded {
+                    address: a1,
+                    index: i1,
+                    wallet_id: w1,
+                },
+                AddressView::Decoded {
+                    address: a2,
+                    index: i2,
+                    wallet_id: w2,
+                },
+            ) => match a1.cmp(a2) {
+                Ordering::Equal => match i1.cmp(i2) {
+                    Ordering::Equal => w1.cmp(w2),
+                    ord => ord,
+                },
+                ord => ord,
+            },
+            (
+                AddressView::Opaque { address: _ },
+                AddressView::Decoded {
+                    address: _,
+                    index: _,
+                    wallet_id: _,
+                },
+            ) => Ordering::Less,
+            (
+                AddressView::Decoded {
+                    address: _,
+                    index: _,
+                    wallet_id: _,
+                },
+                AddressView::Opaque { address: _ },
+            ) => Ordering::Greater,
+        }
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use rand_core::OsRng;

crates/core/transaction/src/transaction.rs

@@ -7,14 +7,15 @@ use anyhow::{Context, Error};
 use ark_ff::Zero;
 use decaf377::Fr;
 use decaf377_rdsa::{Binding, Signature, VerificationKey, VerificationKeyBytes};
+use penumbra_asset::Balance;
 use penumbra_community_pool::{CommunityPoolDeposit, CommunityPoolOutput, CommunityPoolSpend};
 use penumbra_dex::{
     lp::action::{PositionClose, PositionOpen},
     swap::Swap,
 };
 use penumbra_governance::{DelegatorVote, ProposalSubmit, ProposalWithdraw, ValidatorVote};
 use penumbra_ibc::IbcRelay;
-use penumbra_keys::{FullViewingKey, PayloadKey};
+use penumbra_keys::{AddressView, FullViewingKey, PayloadKey};
 use penumbra_proto::{
     core::transaction::v1::{self as pbt},
     DomainType, Message,
@@ -44,6 +45,20 @@ pub struct TransactionBody {
     pub memo: Option<MemoCiphertext>,
 }
 
+/// Represents a transaction summary containing multiple effects.
+#[derive(Debug, Clone, Default, Serialize, Deserialize)]
+#[serde(try_from = "pbt::TransactionSummary", into = "pbt::TransactionSummary")]
+pub struct TransactionSummary {
+    pub effects: Vec<TransactionEffect>,
+}
+
+/// Represents an individual effect of a transaction.
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+pub struct TransactionEffect {
+    pub address: AddressView,
+    pub balance: Balance,
+}
+
 impl EffectingData for TransactionBody {
     fn effect_hash(&self) -> EffectHash {
         let mut state = blake2b_simd::Params::new()
@@ -591,6 +606,50 @@ impl Transaction {
     }
 }
 
+impl DomainType for TransactionSummary {
+    type Proto = pbt::TransactionSummary;
+}
+
+impl From<TransactionSummary> for pbt::TransactionSummary {
+    fn from(summary: TransactionSummary) -> Self {
+        pbt::TransactionSummary {
+            effects: summary
+                .effects
+                .into_iter()
+                .map(|effect| pbt::transaction_summary::Effects {
+                    address: Some(effect.address.into()),
+                    balance: Some(effect.balance.into()),
+                })
+                .collect(),
+        }
+    }
+}
+
+impl TryFrom<pbt::TransactionSummary> for TransactionSummary {
+    type Error = anyhow::Error;
+
+    fn try_from(pbt: pbt::TransactionSummary) -> Result<Self, Self::Error> {
+        let effects = pbt
+            .effects
+            .into_iter()
+            .map(|effect| {
+                Ok(TransactionEffect {
+                    address: effect
+                        .address
+                        .ok_or_else(|| anyhow::anyhow!("missing address field"))?
+                        .try_into()?,
+                    balance: effect
+                        .balance
+                        .ok_or_else(|| anyhow::anyhow!("missing balance field"))?
+                        .try_into()?,
+                })
+            })
+            .collect::<Result<Vec<TransactionEffect>, anyhow::Error>>()?;
+
+        Ok(Self { effects })
+    }
+}
+
 impl DomainType for TransactionBody {
     type Proto = pbt::TransactionBody;
 }
@@ -662,7 +721,12 @@ impl From<Transaction> for pbt::Transaction {
 
 impl From<&Transaction> for pbt::Transaction {
     fn from(msg: &Transaction) -> Self {
-        msg.into()
+        Transaction {
+            transaction_body: msg.transaction_body.clone(),
+            anchor: msg.anchor.clone(),
+            binding_sig: msg.binding_sig.clone(),
+        }
+        .into()
     }
 }