Feat/solver extensions and batch

intent_settlement/src/lib.rs

@@ -20,6 +20,8 @@ const INTENT_EXPIRY: u64 = 1800; // 30 minutes
 const FILL_WINDOW: u64 = 300; // 5 minutes to fill after intent accepted
 const MIN_BOND: i128 = 50 * 10_000_000; // 50 USDC minimum solver bond
 const PROTOCOL_FEE_BPS: i128 = 5; // 0.05%
+const MAX_BATCH_SIZE: u32 = 100; // Maximum items per batch operation
+const MAX_EXTENSION_DURATION: u64 = 300; // 5 minutes max extension time
 
 // Soroban archives ledger entries that go too long without being touched.
 // Persistent Intent/Solver records get their TTL bumped on every write so
@@ -50,6 +52,7 @@ pub enum DataKey {
     Paused,
     AllowedDstToken(Address), // dst_token -> present if allowed
     DstAllowlistEnabled,
+    ExtensionGranted(BytesN<32>), // intent_id -> true if extension already granted
 }
 
 // ─── Data Structs ─────────────────────────────────────────────────────────────
@@ -793,6 +796,112 @@ impl IntentSettlement {
             .publish((Symbol::new(&env, "intent_expired"),), intent_id);
     }
 
+    // ── Batch Operations ──────────────────────────────────────────────────────
+
+    /// Submit multiple intents in a single transaction.
+    /// Processes all intents in the batch; a failure partway through will
+    /// revert the entire batch (Soroban transaction atomicity).
+    /// Bounded by MAX_BATCH_SIZE to prevent resource exhaustion.
+    pub fn batch_submit_intent(
+        env: Env,
+        user: Address,
+        intents: soroban_sdk::Vec<(String, String, i128, Address, i128, Option<u64>)>,
+    ) -> soroban_sdk::Vec<BytesN<32>> {
+        if intents.len() > MAX_BATCH_SIZE as usize {
+            panic_with_error!(&env, Error::ZeroAmount); // No dedicated error; reuse nearest
+        }
+
+        let mut result = soroban_sdk::Vec::new(&env);
+        for (src_chain, src_token, src_amount, dst_token, min_dst_amount, deadline) in intents {
+            let intent_id = Self::submit_intent(
+                env.clone(),
+                user.clone(),
+                src_chain,
+                src_token,
+                src_amount,
+                dst_token,
+                min_dst_amount,
+                deadline,
+            );
+            result.push_back(intent_id);
+        }
+        result
+    }
+
+    /// Accept multiple intents in a single transaction.
+    /// Processes all intents in the batch; a failure partway through will
+    /// revert the entire batch (Soroban transaction atomicity).
+    /// Bounded by MAX_BATCH_SIZE to prevent resource exhaustion.
+    pub fn batch_accept_intent(
+        env: Env,
+        solver: Address,
+        intent_ids: soroban_sdk::Vec<BytesN<32>>,
+    ) {
+        if intent_ids.len() > MAX_BATCH_SIZE as usize {
+            panic_with_error!(&env, Error::ZeroAmount); // No dedicated error; reuse nearest
+        }
+
+        for intent_id in intent_ids {
+            Self::accept_intent(env.clone(), solver.clone(), intent_id);
+        }
+    }
+
+    // ── Fill Window Extension ─────────────────────────────────────────────────
+
+    /// Solver requests a grace-period extension on an Accepted intent.
+    /// Grants exactly one extension per intent, each extending the deadline
+    /// by up to MAX_EXTENSION_DURATION. Further extension requests on the
+    /// same intent are rejected to prevent abuse.
+    pub fn request_extension(env: Env, solver: Address, intent_id: BytesN<32>) {
+        solver.require_auth();
+        Self::bump_instance_ttl(&env);
+
+        let mut intent: IntentRecord = env
+            .storage()
+            .persistent()
+            .get(&DataKey::Intent(intent_id.clone()))
+            .unwrap_or_else(|| panic_with_error!(&env, Error::IntentNotFound));
+
+        // Only Accepted intents can be extended
+        if intent.state != IntentState::Accepted {
+            panic_with_error!(&env, Error::IntentNotAccepted);
+        }
+
+        // Only the assigned solver can request an extension
+        if intent.solver.as_ref() != Some(&solver) {
+            panic_with_error!(&env, Error::Unauthorized);
+        }
+
+        // Each intent gets exactly one extension
+        if env
+            .storage()
+            .persistent()
+            .has(&DataKey::ExtensionGranted(intent_id.clone()))
+        {
+            panic_with_error!(&env, Error::ZeroAmount); // No dedicated error; reuse nearest
+        }
+
+        let now = env.ledger().timestamp();
+
+        // Extend the deadline by the full extension duration
+        intent.deadline = now + MAX_EXTENSION_DURATION;
+
+        // Record that this intent has used its one extension
+        env.storage()
+            .persistent()
+            .set(&DataKey::ExtensionGranted(intent_id.clone()), &true);
+
+        env.storage()
+            .persistent()
+            .set(&DataKey::Intent(intent_id.clone()), &intent);
+        Self::bump_intent_ttl(&env, &intent_id);
+
+        env.events().publish(
+            (Symbol::new(&env, "extension_granted"), solver),
+            (intent_id, intent.deadline),
+        );
+    }
+
     // ── Views ─────────────────────────────────────────────────────────────────
 
     /// Fetch an intent's full record by id, or None if it was never submitted.
@@ -847,6 +956,14 @@ impl IntentSettlement {
         (intents, volume)
     }
 
+    /// Total number of solvers ever registered.
+    pub fn get_solver_count(env: Env) -> u32 {
+        env.storage()
+            .instance()
+            .get(&DataKey::TotalSolvers)
+            .unwrap_or(0)
+    }
+
     // ── Internal ──────────────────────────────────────────────────────────────
 
     fn require_admin(env: &Env) {