bigz/amm-fee-pool-insurance

programs/drift/src/controller/liquidation.rs

@@ -3,6 +3,7 @@ use std::ops::{Deref, DerefMut};
 use anchor_lang::prelude::*;
 use solana_program::msg;
 
+use crate::controller::amm::get_fee_pool_tokens;
 use crate::controller::funding::settle_funding_payment;
 use crate::controller::lp::burn_lp_shares;
 use crate::controller::orders;
@@ -45,6 +46,7 @@ use crate::math::orders::{
 };
 use crate::math::position::calculate_base_asset_value_with_oracle_price;
 use crate::math::safe_math::SafeMath;
+use crate::math::spot_balance::get_token_amount;
 use crate::math::spot_balance::get_token_value;
 use crate::state::events::{
     LiquidateBorrowForPerpPnlRecord, LiquidatePerpPnlForDepositRecord, LiquidatePerpRecord,
@@ -2081,7 +2083,32 @@ pub fn resolve_perp_bankruptcy(
         if_payment
     };
 
-    let loss_to_socialize = loss.safe_add(if_payment.cast::<i128>()?)?;
+    let losses_remaining: i128 = loss.safe_add(if_payment.cast::<i128>()?)?;
+
+    let fee_pool_payment: i128 = if losses_remaining > 0 {
+        let perp_market = &mut perp_market_map.get_ref_mut(&market_index)?;
+        let spot_market = &mut spot_market_map.get_ref_mut(&QUOTE_SPOT_MARKET_INDEX)?;
+        let fee_pool_tokens = get_fee_pool_tokens(perp_market, spot_market)?;
+
+        let payment = losses_remaining.min(fee_pool_tokens.cast()?);
+        payment
+    } else {
+        0
+    };
+
+    if fee_pool_payment != 0 {
+        let perp_market = &mut perp_market_map.get_ref_mut(&market_index)?;
+        let spot_market = &mut spot_market_map.get_ref_mut(&QUOTE_SPOT_MARKET_INDEX)?;
+        update_spot_balances(
+            fee_pool_payment.unsigned_abs(),
+            &SpotBalanceType::Borrow,
+            spot_market,
+            &mut perp_market.amm.fee_pool,
+            false,
+        )?;
+    }
+
+    let loss_to_socialize = losses_remaining.safe_add(fee_pool_payment.cast::<i128>()?)?;
 
     let cumulative_funding_rate_delta = calculate_funding_rate_deltas_to_resolve_bankruptcy(
         loss_to_socialize,