From 183529b08f3443519c232b75f7fc3f5378a128b7 Mon Sep 17 00:00:00 2001
From: Kris Nuttycombe <kris@nutty.land>
Date: Thu, 7 Mar 2024 14:18:30 -0700
Subject: [PATCH] WIP: zcash_client_backend: Implement generation of ZIP-320
 compliant proposals.

---
 .../src/data_api/wallet/input_selection.rs         | 14 +++++++++++++-
 zcash_keys/src/address.rs                          |  5 +++++
 2 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/zcash_client_backend/src/data_api/wallet/input_selection.rs b/zcash_client_backend/src/data_api/wallet/input_selection.rs
index ebf891ca1c..d97329d091 100644
--- a/zcash_client_backend/src/data_api/wallet/input_selection.rs
+++ b/zcash_client_backend/src/data_api/wallet/input_selection.rs
@@ -4,7 +4,7 @@ use core::marker::PhantomData;
 use std::{
     collections::BTreeMap,
     error,
-    fmt::{self, Debug, Display},
+    fmt::{self, Debug, Display}, ptr::addr_of_mut,
 };
 
 use nonempty::NonEmpty;
@@ -343,6 +343,7 @@ where
         #[cfg(feature = "orchard")]
         let mut orchard_outputs = vec![];
         let mut payment_pools = BTreeMap::new();
+        let mut ephemeral_transparent_output: Option<(TransparentAddress, NonNegativeAmount)> = None;
         for (idx, payment) in transaction_request.payments() {
             match &payment.recipient_address {
                 Address::Transparent(addr) => {
@@ -352,6 +353,17 @@ where
                         script_pubkey: addr.script(),
                     });
                 }
+                Address::TransparentSourceOnlyTransparent(_) => {
+                    if let Some((addr, amount)) = ephemeral_transparent_output {
+                        ephemeral_transparent_output = Some((addr, amount + payment.amount));
+                    } else {
+                        // create ephemeral address
+                        let ephemeral_addr = wallet_db
+                            .get_new_transparent_address(account, TransparentKeyScope::custom(2))
+                            .map_err(InputSelectorError::DataSource)?;
+                        ephemeral_transparent_output = Some((ephemeral_addr, payment.amount + 10000))
+                    }
+                }
                 Address::Sapling(_) => {
                     payment_pools.insert(*idx, PoolType::Shielded(ShieldedProtocol::Sapling));
                     sapling_outputs.push(SaplingPayment(payment.amount));
diff --git a/zcash_keys/src/address.rs b/zcash_keys/src/address.rs
index dd1fb9ac43..8793ae2ca1 100644
--- a/zcash_keys/src/address.rs
+++ b/zcash_keys/src/address.rs
@@ -240,6 +240,7 @@ pub enum Address {
     Sapling(PaymentAddress),
     Transparent(TransparentAddress),
     Unified(UnifiedAddress),
+    TransparentSourceOnlyTransparent(TransparentAddress)
 }
 
 #[cfg(feature = "sapling")]
@@ -287,6 +288,10 @@ impl TryFromRawAddress for Address {
     fn try_from_raw_transparent_p2sh(data: [u8; 20]) -> Result<Self, ConversionError<Self::Error>> {
         Ok(TransparentAddress::ScriptHash(data).into())
     }
+
+    fn try_from_raw_tex(data: [u8; 20]) -> Result<Self, ConversionError<Self::Error>> {        
+        Ok(Address::TransparentSourceOnlyTransparent(TransparentAddress::PublicKeyHash(data)))
+    }
 }
 
 impl Address {