feat: dedicated collateral coin utility

feat: dedicated dig coin utility
feat: error handling improvements

Author: wwills2

src/dig_coin.rs

@@ -0,0 +1,88 @@
+use crate::error::WalletError;
+use crate::wallet::DIG_ASSET_ID;
+use crate::{Bytes32, Coin, Peer};
+use chia::protocol::CoinState;
+use chia::puzzles::cat::CatArgs;
+use chia_wallet_sdk::driver::{Asset, Cat, Puzzle, SpendContext};
+use chia_wallet_sdk::prelude::{TreeHash, MAINNET_CONSTANTS};
+
+pub struct DigCoin {
+    cat: Cat,
+}
+
+impl DigCoin {
+    #[inline]
+    pub fn cat(&self) -> Cat {
+        self.cat
+    }
+
+    pub fn puzzle_hash(wallet_puzzle_hash: Bytes32) -> Bytes32 {
+        let ph_bytes =
+            CatArgs::curry_tree_hash(DIG_ASSET_ID, TreeHash::from(wallet_puzzle_hash)).to_bytes();
+        Bytes32::from(ph_bytes)
+    }
+
+    pub async fn from_coin_state(peer: &Peer, coin_state: &CoinState) -> Result<Self, WalletError> {
+        let coin_created_height = coin_state.created_height.ok_or(WalletError::Parse(
+            "Cannot determine coin creation height".to_string(),
+        ))?;
+        Self::from_coin(peer, &coin_state.coin, coin_created_height).await
+    }
+
+    /// Function to validate that a coin is a $DIG CAT coin. Returns an instantiated DIG token
+    /// CAT for the coin if it's a valid $DIG CAT
+    pub async fn from_coin(
+        peer: &Peer,
+        coin: &Coin,
+        coin_created_height: u32,
+    ) -> Result<Self, WalletError> {
+        let mut ctx = SpendContext::new();
+
+        // 1) Request parent coin state
+        let parent_state_response = peer
+            .request_coin_state(
+                vec![coin.parent_coin_info],
+                None,
+                MAINNET_CONSTANTS.genesis_challenge,
+                false,
+            )
+            .await?;
+
+        let parent_state = parent_state_response.map_err(|_| WalletError::RejectCoinState)?;
+
+        // 2) Request parent puzzle and solution
+        let parent_puzzle_and_solution_response = peer
+            .request_puzzle_and_solution(parent_state.coin_ids[0], coin_created_height)
+            .await?;
+
+        let parent_puzzle_and_solution =
+            parent_puzzle_and_solution_response.map_err(|_| WalletError::RejectPuzzleSolution)?;
+
+        // 3) Convert puzzle to CLVM
+        let parent_puzzle_ptr = ctx.alloc(&parent_puzzle_and_solution.puzzle)?;
+        let parent_puzzle = Puzzle::parse(&ctx, parent_puzzle_ptr);
+
+        // 4) Convert solution to CLVM
+        let parent_solution = ctx.alloc(&parent_puzzle_and_solution.solution)?;
+
+        // 5) Parse CAT
+        let parsed_children = Cat::parse_children(
+            &mut ctx,
+            parent_state.coin_states[0].coin,
+            parent_puzzle,
+            parent_solution,
+        )?
+        .ok_or(WalletError::UnknownCoin)?;
+
+        let proved_cat = parsed_children
+            .into_iter()
+            .find(|parsed_child| {
+                parsed_child.coin_id() == coin.coin_id()
+                    && parsed_child.lineage_proof.is_some()
+                    && parsed_child.info.asset_id == DIG_ASSET_ID
+            })
+            .ok_or_else(|| WalletError::UnknownCoin)?;
+
+        Ok(Self { cat: proved_cat })
+    }
+}

src/dig_collateral_coin.rs

@@ -0,0 +1,255 @@
+use crate::dig_coin::DigCoin;
+use crate::error::WalletError;
+use crate::wallet::DIG_ASSET_ID;
+use crate::{Bytes, Bytes32, Coin, CoinSpend, CoinState, P2ParentCoin, Peer, PublicKey};
+use chia::puzzles::Memos;
+use chia::traits::Streamable;
+use chia_wallet_sdk::driver::{
+    Action, Id, Puzzle, Relation, SpendContext, SpendWithConditions, Spends, StandardLayer,
+};
+use chia_wallet_sdk::prelude::{AssertConcurrentSpend, Conditions, ToTreeHash, MAINNET_CONSTANTS};
+use clvm_traits::{FromClvm, ToClvm};
+use clvmr::Allocator;
+use indexmap::indexmap;
+use num_bigint::BigInt;
+
+pub struct DigCollateralCoin {
+    inner: P2ParentCoin,
+    morphed_store_id: Option<Bytes32>,
+    mirror_urls: Option<Vec<String>>,
+}
+
+impl DigCollateralCoin {
+    /// Morphs a DIG store launcher ID into the DIG store collateral coin namespace.
+    pub fn morph_store_launcher_if_for_collateral(store_launcher_id: Bytes32) -> Bytes32 {
+        (store_launcher_id, "DIG_STORE_COLLATERAL")
+            .tree_hash()
+            .into()
+    }
+
+    /// Morphs a DIG store launcher ID into the DIG mirror collateral coin namespace.
+    pub fn morph_store_launcher_id_for_mirror(
+        store_launcher_id: Bytes32,
+        offset: &BigInt,
+    ) -> Bytes32 {
+        let launcher_id_int = BigInt::from_signed_bytes_be(&store_launcher_id);
+        let offset_launcher_id = launcher_id_int + offset;
+
+        (offset_launcher_id, "DIG_STORE_MIRROR_COLLATERAL")
+            .tree_hash()
+            .into()
+    }
+
+    /// Instantiates a $DIG collateral coin
+    /// Verifies that coin is unspent and locked by the $DIG P2Parent puzzle
+    pub async fn from_coin_state(peer: &Peer, coin_state: CoinState) -> Result<Self, WalletError> {
+        let coin = coin_state.coin;
+
+        // verify coin is unspent
+        if matches!(coin_state.spent_height, Some(x) if x != 0) {
+            return Err(WalletError::CoinIsAlreadySpent);
+        }
+
+        // verify that the coin is $DIG p2 parent
+        let p2_parent_hash = P2ParentCoin::puzzle_hash(Some(DIG_ASSET_ID));
+        if coin.puzzle_hash != p2_parent_hash.into() {
+            return Err(WalletError::PuzzleHashMismatch(format!(
+                "Coin {} is not locked by the $DIG collateral puzzle",
+                coin.coin_id()
+            )));
+        }
+
+        let Some(created_height) = coin_state.created_height else {
+            return Err(WalletError::UnknownCoin);
+        };
+
+        let parent_state = peer
+            .request_coin_state(
+                vec![coin.parent_coin_info],
+                None,
+                MAINNET_CONSTANTS.genesis_challenge,
+                false,
+            )
+            .await?
+            .map_err(|_| WalletError::RejectCoinState)?
+            .coin_states
+            .first()
+            .copied()
+            .ok_or(WalletError::UnknownCoin)?;
+
+        let parent_puzzle_and_solution_response = peer
+            .request_puzzle_and_solution(coin.parent_coin_info, created_height)
+            .await?
+            .map_err(|_| WalletError::RejectPuzzleSolution)?;
+
+        let mut allocator = Allocator::new();
+        let parent_puzzle_ptr = parent_puzzle_and_solution_response
+            .puzzle
+            .to_clvm(&mut allocator)?;
+        let parent_solution_ptr = parent_puzzle_and_solution_response
+            .solution
+            .to_clvm(&mut allocator)?;
+
+        let parent_puzzle = Puzzle::parse(&allocator, parent_puzzle_ptr);
+
+        let (p2_parent, memos) = P2ParentCoin::parse_child(
+            &mut allocator,
+            parent_state.coin,
+            parent_puzzle,
+            parent_solution_ptr,
+        )?
+        .ok_or(WalletError::Parse(
+            "Failed to instantiate from parent state".to_string(),
+        ))?;
+
+        let memos_vec = match memos {
+            Memos::Some(node) => Vec::<Bytes>::from_clvm(&mut allocator, node)
+                .ok()
+                .unwrap_or_default(),
+            Memos::None => Vec::new(),
+        };
+
+        let morphed_store_id: Option<Bytes32> = if memos_vec.is_empty() {
+            None
+        } else {
+            Bytes32::from_bytes(&memos_vec[0]).ok()
+        };
+
+        let mut mirror_urls_vec = Vec::new();
+        for i in 1..memos_vec.len() {
+            if let Ok(url_string) = String::from_utf8(memos_vec[i].to_vec()) {
+                mirror_urls_vec.push(url_string);
+            }
+        }
+
+        let mirror_urls = if mirror_urls_vec.is_empty() {
+            None
+        } else {
+            Some(mirror_urls_vec)
+        };
+
+        Ok(Self {
+            inner: p2_parent,
+            morphed_store_id,
+            mirror_urls,
+        })
+    }
+
+    /// Uses the specified $DIG to create a collateral coin for the provided DIG store ID (launcher ID)
+    pub fn create(
+        dig_coins: Vec<DigCoin>,
+        collateral_amount: u64,
+        store_id: Bytes32,
+        mirror_urls: Option<Vec<String>>,
+        synthetic_key: PublicKey,
+        fee_coins: Vec<Coin>,
+        fee: u64,
+    ) -> Result<Vec<CoinSpend>, WalletError> {
+        let p2_parent_inner_hash = P2ParentCoin::inner_puzzle_hash(Some(DIG_ASSET_ID));
+
+        let mut ctx = SpendContext::new();
+
+        let morphed_store_id = Self::morph_store_launcher_if_for_collateral(store_id);
+
+        let memos = match mirror_urls {
+            Some(urls) => {
+                let mut memos_vec = Vec::with_capacity(urls.len() + 1);
+                memos_vec.push(morphed_store_id.to_vec());
+
+                for url in &urls {
+                    memos_vec.push(url.as_bytes().to_vec());
+                }
+
+                let memos_node_ptr = ctx.alloc(&memos_vec)?;
+                Memos::Some(memos_node_ptr)
+            }
+            None => ctx.hint(morphed_store_id)?,
+        };
+
+        let actions = [
+            Action::fee(fee),
+            Action::send(
+                Id::Existing(DIG_ASSET_ID),
+                p2_parent_inner_hash.into(),
+                collateral_amount,
+                memos,
+            ),
+        ];
+
+        let p2_layer = StandardLayer::new(synthetic_key);
+        let p2_puzzle_hash: Bytes32 = p2_layer.tree_hash().into();
+        let mut spends = Spends::new(p2_puzzle_hash);
+
+        // add collateral coins to spends
+        for dig_coin in dig_coins {
+            spends.add(dig_coin.cat());
+        }
+
+        // add fee coins to spends
+        for fee_xch_coin in fee_coins {
+            spends.add(fee_xch_coin);
+        }
+
+        let deltas = spends.apply(&mut ctx, &actions)?;
+        let index_map = indexmap! {p2_puzzle_hash => synthetic_key};
+
+        let _outputs =
+            spends.finish_with_keys(&mut ctx, &deltas, Relation::AssertConcurrent, &index_map)?;
+
+        Ok(ctx.take())
+    }
+
+    /// Builds the spend bundle for spending the $DIG collateral coin to de-collateralize
+    /// the store and return spendable $DIG to the wallet that created the collateral coin.
+    pub fn spend(
+        &self,
+        synthetic_key: PublicKey,
+        fee_coins: Vec<Coin>,
+        fee: u64,
+    ) -> Result<Vec<CoinSpend>, WalletError> {
+        let p2_layer = StandardLayer::new(synthetic_key);
+        let p2_puzzle_hash: Bytes32 = p2_layer.tree_hash().into();
+
+        if p2_puzzle_hash != self.inner.proof.parent_inner_puzzle_hash {
+            return Err(WalletError::PuzzleHashMismatch(
+                "This coin is not owned by this wallet".to_string(),
+            ));
+        }
+
+        let collateral_spend_conditions =
+            Conditions::new().create_coin(p2_puzzle_hash, self.inner.coin.amount, Memos::None);
+
+        let mut ctx = SpendContext::new();
+
+        // add the collateral p2 parent spend to the spend context
+        let p2_delegated_spend =
+            p2_layer.spend_with_conditions(&mut ctx, collateral_spend_conditions)?;
+
+        self.inner.spend(&mut ctx, p2_delegated_spend, ())?;
+
+        // use actions and spends to attach fee to transaction and generate change
+        let actions = [Action::fee(fee)];
+        let mut fee_spends = Spends::new(p2_puzzle_hash);
+        fee_spends
+            .conditions
+            .required
+            .push(AssertConcurrentSpend::new(self.inner.coin.coin_id()));
+
+        // add fee coins to spends
+        for fee_xch_coin in fee_coins {
+            fee_spends.add(fee_xch_coin);
+        }
+
+        let deltas = fee_spends.apply(&mut ctx, &actions)?;
+        let index_map = indexmap! {p2_puzzle_hash => synthetic_key};
+
+        let _outputs = fee_spends.finish_with_keys(
+            &mut ctx,
+            &deltas,
+            Relation::AssertConcurrent,
+            &index_map,
+        )?;
+
+        Ok(ctx.take())
+    }
+}

src/error.rs

@@ -23,14 +23,15 @@ pub enum WalletError {
     #[error("{0:?}")]
     Driver(#[from] DriverError),
 
-    #[error("ParseError")]
-    Parse,
+    #[error("ParseError: {0}")]
+    Parse(String),
 
     #[error("UnknownCoin")]
     UnknownCoin,
 
     #[error("Clvm error")]
     Clvm,
+
     #[error("ToClvm error: {0}")]
     ToClvm(#[from] chia::clvm_traits::ToClvmError),