feat(soroban): add account monitoring contract for master account

crates/contracts/core/src/account_monitor/src/events.rs

@@ -0,0 +1,10 @@
+#![no_std]
+use soroban_sdk::{Address, Env, symbol_short};
+
+pub fn low_balance_alert(env: &Env, account: Address, balance: u32) {
+    env.events().publish((symbol_short!("low_balance"),), (account, balance));
+}
+
+pub fn transaction_logged(env: &Env, account: Address, tx_count: u32) {
+    env.events().publish((symbol_short!("tx_logged"),), (account, tx_count));
+}

crates/contracts/core/src/account_monitor/src/lib.rs

@@ -0,0 +1,56 @@
+#![no_std]
+
+mod storage;
+mod events;
+mod thresholds;
+
+use soroban_sdk::{contract, contractimpl, Env, Address, u32};
+
+#[contract]
+pub struct AccountMonitorContract;
+
+#[contractimpl]
+impl AccountMonitorContract {
+
+    // Initialize with master account address and low balance threshold
+    pub fn initialize(env: Env, master: Address, low_balance: u32) {
+        if env.storage().has(&storage::DataKey::MasterAccount) {
+            panic!("Already initialized");
+        }
+        env.storage().set(&storage::DataKey::MasterAccount, &master);
+        env.storage().set(&storage::DataKey::TransactionCount, &0u32);
+        thresholds::set_low_balance_threshold(&env, low_balance);
+    }
+
+    // Log a transaction
+    pub fn log_transaction(env: Env) {
+        let master: Address = env.storage().get(&storage::DataKey::MasterAccount).unwrap();
+        let count: u32 = env.storage().get(&storage::DataKey::TransactionCount).unwrap_or(0);
+        let new_count = count + 1;
+        env.storage().set(&storage::DataKey::TransactionCount, &new_count);
+        events::transaction_logged(&env, master, new_count);
+    }
+
+    // Check for low balance and emit alert if necessary
+    pub fn check_low_balance(env: Env, current_balance: u32) {
+        let master: Address = env.storage().get(&storage::DataKey::MasterAccount).unwrap();
+        let threshold = thresholds::get_low_balance_threshold(&env);
+        if current_balance < threshold {
+            events::low_balance_alert(&env, master, current_balance);
+        }
+    }
+
+    // Set / get threshold
+    pub fn set_low_balance_threshold(env: Env, threshold: u32) {
+        thresholds::set_low_balance_threshold(&env, threshold);
+    }
+
+    pub fn get_low_balance_threshold(env: Env) -> u32 {
+        thresholds::get_low_balance_threshold(&env)
+    }
+
+    // Get transaction count
+    pub fn get_transaction_count(env: Env) -> u32 {
+        env.storage().get(&storage::DataKey::TransactionCount).unwrap_or(0)
+    }
+}

crates/contracts/core/src/account_monitor/src/storage.rs

@@ -0,0 +1,9 @@
+#![no_std]
+use soroban_sdk::{contracttype, Address};
+
+#[contracttype]
+pub enum DataKey {
+    MasterAccount,
+    TransactionCount,
+    LowBalanceThreshold,
+}

crates/contracts/core/src/account_monitor/src/thresholds.rs

@@ -0,0 +1,11 @@
+#![no_std]
+use soroban_sdk::{Env, u32};
+use crate::storage::DataKey;
+
+pub fn set_low_balance_threshold(env: &Env, threshold: u32) {
+    env.storage().set(&DataKey::LowBalanceThreshold, &threshold);
+}
+
+pub fn get_low_balance_threshold(env: &Env) -> u32 {
+    env.storage().get(&DataKey::LowBalanceThreshold).unwrap_or(0)
+}