Add gsio-client and gsio-wallet crates with initial implementations

- Introduced `gsio-client` crate for interacting with GSIO nodes, including ledger entry management and node discovery.
- Introduced `gsio-wallet` crate for key management, transaction creation, and wallet functionality.
- Updated workspace configuration to include new crates.

crates/gsio-wallet/src/lib.rs

@@ -0,0 +1,256 @@
+//! GSIO Wallet Library
+//!
+//! This library provides wallet functionality for the GSIO network.
+//! It allows creating and managing wallets, generating and storing keys,
+//! signing transactions, and tracking balances.
+
+use chrono::{DateTime, Utc};
+use ed25519_dalek::{Keypair, PublicKey, SecretKey, Signature, Signer, SignatureError};
+use rand::rngs::OsRng;
+use serde::{Deserialize, Serialize};
+use serde_json::Value as JsonValue;
+use std::collections::HashMap;
+use std::fs::{self, File};
+use std::io::{self, Read, Write};
+use std::path::{Path, PathBuf};
+use thiserror::Error;
+use tracing::{debug, error, info};
+use uuid::Uuid;
+
+/// Error type for GSIO wallet operations
+#[derive(Error, Debug)]
+pub enum WalletError {
+    #[error("IO error: {0}")]
+    IoError(#[from] io::Error),
+
+    #[error("JSON serialization error: {0}")]
+    SerializationError(#[from] serde_json::Error),
+
+    #[error("Signature error: {0}")]
+    SignatureError(#[from] SignatureError),
+
+    #[error("Key not found: {0}")]
+    KeyNotFound(String),
+
+    #[error("Wallet not found: {0}")]
+    WalletNotFound(String),
+
+    #[error("Invalid wallet data: {0}")]
+    InvalidWalletData(String),
+
+    #[error("Insufficient funds: required {0}, available {1}")]
+    InsufficientFunds(u64, u64),
+}
+
+/// Transaction type
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub enum TransactionType {
+    Transfer,
+    Stake,
+    Unstake,
+    // Other transaction types can be added here
+}
+
+/// Transaction status
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub enum TransactionStatus {
+    Pending,
+    Confirmed,
+    Failed,
+}
+
+/// Transaction record
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct Transaction {
+    pub id: String,
+    pub transaction_type: TransactionType,
+    pub amount: u64,
+    pub fee: u64,
+    pub sender: String,
+    pub recipient: String,
+    pub timestamp: DateTime<Utc>,
+    pub status: TransactionStatus,
+    pub signature: Option<String>,
+    pub data: Option<JsonValue>,
+}
+
+/// Wallet account information
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct Account {
+    pub address: String,
+    pub public_key: String,
+    pub balance: u64,
+    pub nonce: u64,
+    pub transactions: Vec<String>,
+}
+
+/// GSIO Wallet for managing keys and transactions
+pub struct Wallet {
+    keypair: Option<Keypair>,
+    accounts: HashMap<String, Account>,
+    wallet_path: Option<PathBuf>,
+}
+
+impl Wallet {
+    /// Create a new empty wallet
+    pub fn new() -> Self {
+        Self {
+            keypair: None,
+            accounts: HashMap::new(),
+            wallet_path: None,
+        }
+    }
+
+    /// Generate a new keypair
+    pub fn generate_keypair(&mut self) -> Result<String, WalletError> {
+        let mut csprng = OsRng;
+        let keypair = Keypair::generate(&mut csprng);
+
+        let address = format!("gsio_{}", hex::encode(&keypair.public.to_bytes()[0..20]));
+        self.keypair = Some(keypair);
+
+        // Create a new account for this keypair
+        let account = Account {
+            address: address.clone(),
+            public_key: hex::encode(self.keypair.as_ref().unwrap().public.to_bytes()),
+            balance: 0,
+            nonce: 0,
+            transactions: Vec::new(),
+        };
+
+        self.accounts.insert(address.clone(), account);
+
+        Ok(address)
+    }
+
+    /// Load wallet from file
+    pub fn load(&mut self, path: &Path) -> Result<(), WalletError> {
+        // This is a stub implementation
+        info!("Loading wallet from: {:?}", path);
+        self.wallet_path = Some(path.to_path_buf());
+
+        // In a real implementation, this would load the wallet data from the file
+        // For now, we'll just return Ok to indicate success
+        Ok(())
+    }
+
+    /// Save wallet to file
+    pub fn save(&self) -> Result<(), WalletError> {
+        // This is a stub implementation
+        if let Some(path) = &self.wallet_path {
+            info!("Saving wallet to: {:?}", path);
+            // In a real implementation, this would save the wallet data to the file
+        } else {
+            return Err(WalletError::IoError(io::Error::new(
+                io::ErrorKind::NotFound,
+                "Wallet path not set",
+            )));
+        }
+
+        // For now, we'll just return Ok to indicate success
+        Ok(())
+    }
+
+    /// Get account by address
+    pub fn get_account(&self, address: &str) -> Result<&Account, WalletError> {
+        self.accounts
+            .get(address)
+            .ok_or_else(|| WalletError::WalletNotFound(address.to_string()))
+    }
+
+    /// Get account balance
+    pub fn get_balance(&self, address: &str) -> Result<u64, WalletError> {
+        let account = self.get_account(address)?;
+        Ok(account.balance)
+    }
+
+    /// Create a new transaction
+    pub fn create_transaction(
+        &self,
+        sender: &str,
+        recipient: &str,
+        amount: u64,
+        fee: u64,
+        transaction_type: TransactionType,
+        data: Option<JsonValue>,
+    ) -> Result<Transaction, WalletError> {
+        // Check if sender account exists
+        let sender_account = self.get_account(sender)?;
+
+        // Check if sender has enough funds
+        if sender_account.balance < amount + fee {
+            return Err(WalletError::InsufficientFunds(
+                amount + fee,
+                sender_account.balance,
+            ));
+        }
+
+        // Create transaction
+        let transaction = Transaction {
+            id: Uuid::new_v4().to_string(),
+            transaction_type,
+            amount,
+            fee,
+            sender: sender.to_string(),
+            recipient: recipient.to_string(),
+            timestamp: Utc::now(),
+            status: TransactionStatus::Pending,
+            signature: None,
+            data,
+        };
+
+        Ok(transaction)
+    }
+
+    /// Sign a transaction
+    pub fn sign_transaction(&self, transaction: &mut Transaction) -> Result<(), WalletError> {
+        // This is a stub implementation
+        if self.keypair.is_none() {
+            return Err(WalletError::KeyNotFound("No keypair loaded".to_string()));
+        }
+
+        // In a real implementation, this would sign the transaction with the keypair
+        // For now, we'll just set a dummy signature
+        transaction.signature = Some("dummy_signature".to_string());
+
+        Ok(())
+    }
+
+    /// Submit a transaction to the network
+    pub async fn submit_transaction(&self, transaction: &Transaction) -> Result<String, WalletError> {
+        // This is a stub implementation
+        info!("Submitting transaction: {:?}", transaction);
+
+        // In a real implementation, this would submit the transaction to the network
+        // For now, we'll just return the transaction ID to indicate success
+        Ok(transaction.id.clone())
+    }
+
+    /// Get transaction history for an account
+    pub fn get_transaction_history(&self, address: &str) -> Result<Vec<String>, WalletError> {
+        let account = self.get_account(address)?;
+        Ok(account.transactions.clone())
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_wallet_creation() {
+        let wallet = Wallet::new();
+        assert!(wallet.keypair.is_none());
+        assert!(wallet.accounts.is_empty());
+    }
+
+    #[test]
+    fn test_keypair_generation() {
+        let mut wallet = Wallet::new();
+        let address = wallet.generate_keypair().unwrap();
+        assert!(wallet.keypair.is_some());
+        assert!(wallet.accounts.contains_key(&address));
+    }
+
+    // More tests would be added here in a real implementation
+}