anya_core/bitcoin/wallet/

mod.rs

// Bitcoin Wallet Module
// Implements unified wallet capabilities for Bitcoin and related chains
//
// [AIR-3][AIS-3][AIT-3][AIM-2][AIP-3][BPC-3][RES-2][SCL-2]
// This module provides comprehensive wallet functionality with high security,
// privacy, and protocol compliance ratings.

use crate::bitcoin::error::BitcoinError;
use crate::bitcoin::interface::BitcoinInterface;
use crate::{AnyaError, AnyaResult};
use async_trait::async_trait;
use bitcoin::absolute::LockTime;
use bitcoin::bip32::DerivationPath;
use bitcoin::hashes::Hash;
use bitcoin::psbt::Psbt as PSBT;
use bitcoin::secp256k1::{Secp256k1, SecretKey};
use bitcoin::{Address, Network, OutPoint, Transaction, TxOut, Txid};
use bitcoin::{Amount, ScriptBuf};
use log::error;
use serde::{Deserialize, Serialize};
use std::collections::HashMap;
use std::path::{Path, PathBuf};
use std::str::FromStr;
use std::sync::{Arc, Mutex};
use thiserror::Error;

pub mod bip32;
pub mod transactions;

#[derive(Debug, Clone, PartialEq, Eq)]
pub enum WalletType {
    Standard,         // Basic Bitcoin wallet
    Taproot,          // Bitcoin with Taproot support
    LightningEnabled, // Bitcoin with Lightning support
    MultiChain,       // Support for multiple chains
}

pub struct WalletConfig {
    pub wallet_type: WalletType,
    pub network: Network,
    pub name: String,
    pub seed_phrase: Option<String>,
    pub password: Option<String>,
    pub receive_descriptor: String,
    pub change_descriptor: String,
    pub xpub: Option<String>,
    pub data_dir: PathBuf,
    pub use_rpc: bool,
    pub coin_selection: CoinSelectionStrategy,
    pub gap_limit: u32,
    pub min_confirmations: u32,
    pub fee_strategy: FeeStrategy,
}

pub trait KeyManager {
    fn derive_key(&self, path: &str) -> AnyaResult<SecretKey>;
    fn get_public_key(&self, path: &str) -> AnyaResult<bitcoin::secp256k1::PublicKey>;
    fn sign_message(&self, message: &[u8], path: &str) -> AnyaResult<Vec<u8>>;
    fn verify_message(&self, message: &[u8], _signature: &[u8], path: &str) -> AnyaResult<bool>;
}

pub trait AddressManager {
    fn get_new_address(&self, address_type: AddressType) -> AnyaResult<Address>;
    fn get_address(&self, index: u32, address_type: AddressType) -> AnyaResult<Address>;
    fn is_address_mine(&self, address: &str) -> AnyaResult<bool>;
    fn get_all_addresses(&self) -> AnyaResult<Vec<Address>>;
}

#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
pub enum AddressType {
    Legacy,       // P2PKH
    SegWit,       // P2WPKH
    NestedSegWit, // P2SH-P2WPKH
    Taproot,      // P2TR
}

pub trait TransactionManager {
    fn create_transaction(
        &self,
        outputs: Vec<(String, u64)>,
        _fee_rate: f64,
        _options: transactions::TxOptions,
    ) -> AnyaResult<Transaction>;

    fn sign_transaction(&self, tx: &mut Transaction) -> AnyaResult<()>;
    fn broadcast_transaction(&self, tx: &Transaction) -> AnyaResult<String>;
    fn get_transaction(&self, txid: &str) -> AnyaResult<Option<Transaction>>;
    fn get_transactions(&self, limit: usize, offset: usize) -> AnyaResult<Vec<Transaction>>;
}

pub trait BalanceManager {
    fn get_balance(&self) -> AnyaResult<u64>;
    fn get_unconfirmed_balance(&self) -> AnyaResult<u64>;
    fn get_asset_balance(&self, asset_id: &str) -> AnyaResult<u64>;
    fn get_all_asset_balances(&self) -> AnyaResult<HashMap<String, u64>>;
}

pub trait UnifiedWallet: KeyManager + AddressManager + TransactionManager + BalanceManager {
    fn name(&self) -> &str;
    fn wallet_type(&self) -> WalletType;
    fn network(&self) -> Network;

    // Chain-specific operations
    fn get_stacks_address(&self) -> AnyaResult<String>;
    fn get_rsk_address(&self) -> AnyaResult<String>;
    fn get_liquid_address(&self) -> AnyaResult<String>;

    // Asset management
    fn add_asset(&self, asset_id: &str, name: &str, asset_type: &str) -> AnyaResult<()>;
    fn remove_asset(&self, asset_id: &str) -> AnyaResult<()>;
    fn get_assets(&self) -> AnyaResult<Vec<Asset>>;

    // Key export/import
    fn export_xpriv(&self, password: &str) -> AnyaResult<String>;
    fn import_xpriv(&self, xpriv: &str, password: &str) -> AnyaResult<()>;

    // Backup management
    fn backup(&self, path: &str, password: &str) -> AnyaResult<()>;
    fn restore(&self, path: &str, password: &str) -> AnyaResult<()>;
}

#[derive(Clone)]
pub struct Asset {
    pub id: String,
    pub name: String,
    pub asset_type: String,
    pub chain: String,
    pub balance: u64,
    pub metadata: HashMap<String, String>,
}

#[allow(dead_code)]
pub struct Wallet {
    config: WalletConfig,
    seed: Mutex<Option<[u8; 64]>>,
    secp: Secp256k1<bitcoin::secp256k1::All>,
    addresses: Mutex<HashMap<AddressType, Vec<Address>>>,
    assets: Mutex<HashMap<String, Asset>>,
    transactions: Mutex<Vec<Transaction>>,
    bitcoin_client: Option<Arc<dyn BitcoinInterface>>,
}

impl Wallet {
    pub fn new(config: WalletConfig, bitcoin_client: Option<Arc<dyn BitcoinInterface>>) -> Self {
        Self {
            config,
            seed: Mutex::new(None),
            secp: Secp256k1::new(),
            addresses: Mutex::new(HashMap::new()),
            assets: Mutex::new(HashMap::new()),
            transactions: Mutex::new(Vec::new()),
            bitcoin_client,
        }
    }

    pub fn initialize(&self, seed_phrase: Option<&str>, password: Option<&str>) -> AnyaResult<()> {
        // Generate or recover seed
        let seed = if let Some(phrase) = seed_phrase {
            bip32::seed_from_mnemonic(phrase, password.unwrap_or(""))?
        } else {
            bip32::generate_seed(password.unwrap_or(""))?
        };

        let mut seed_guard = self
            .seed
            .lock()
            .map_err(|e| format!("Mutex lock error: {e}"))?;
        *seed_guard = Some(seed);

        // Generate initial addresses
        self.init_addresses()?;

        Ok(())
    }

    fn init_addresses(&self) -> AnyaResult<()> {
        let mut addresses = self
            .addresses
            .lock()
            .map_err(|e| format!("Mutex lock error: {e}"))?;

        // Generate 20 addresses of each type
        for address_type in [
            AddressType::Legacy,
            AddressType::SegWit,
            AddressType::NestedSegWit,
            AddressType::Taproot,
        ]
        .iter()
        {
            let mut type_addresses = Vec::new();

            for i in 0..20 {
                let path = match address_type {
                    AddressType::Legacy => format!("m/44'/0'/0'/0/{i}"),
                    AddressType::SegWit => format!("m/84'/0'/0'/0/{i}"),
                    AddressType::NestedSegWit => format!("m/49'/0'/0'/0/{i}"),
                    AddressType::Taproot => format!("m/86'/0'/0'/0/{i}"),
                };

                let secret_key = self.derive_key(&path)?;
                let public_key =
                    bitcoin::secp256k1::PublicKey::from_secret_key(&self.secp, &secret_key);

                // Convert to bitcoin::PublicKey
                let bitcoin_pubkey = bitcoin::PublicKey::new(public_key);
                // Get compressed public key for p2wpkh and p2shwpkh
                let compressed_pubkey = bitcoin::key::CompressedPublicKey::from_slice(
                    &bitcoin_pubkey.inner.serialize(),
                )?;

                let address = match address_type {
                    AddressType::Legacy => Address::p2pkh(bitcoin_pubkey, self.config.network),
                    AddressType::SegWit => Address::p2wpkh(&compressed_pubkey, self.config.network),
                    AddressType::NestedSegWit => {
                        Address::p2shwpkh(&compressed_pubkey, self.config.network)
                    }
                    AddressType::Taproot => {
                        let xonly = bitcoin::secp256k1::XOnlyPublicKey::from(public_key);
                        Address::p2tr(&self.secp, xonly, None, self.config.network)
                    }
                };

                type_addresses.push(address);
            }

            addresses.insert(*address_type, type_addresses);
        }

        Ok(())
    }
}

impl KeyManager for Wallet {
    fn derive_key(&self, path: &str) -> AnyaResult<SecretKey> {
        let seed_guard = self
            .seed
            .lock()
            .map_err(|e| format!("Mutex lock error: {e}"))?;
        let seed = seed_guard
            .as_ref()
            .ok_or_else(|| BitcoinError::Wallet("Wallet not initialized".to_string()))?;

        bip32::derive_key_from_seed(seed, path).map_err(|e| AnyaError::Bitcoin(e.to_string()))
    }

    fn get_public_key(&self, path: &str) -> AnyaResult<bitcoin::secp256k1::PublicKey> {
        let private_key = self.derive_key(path)?;
        let public_key = bitcoin::secp256k1::PublicKey::from_secret_key(&self.secp, &private_key);
        Ok(public_key)
    }

    fn sign_message(&self, message: &[u8], path: &str) -> AnyaResult<Vec<u8>> {
        let private_key = self.derive_key(path)?;

        // Hash the message with SHA256
        let hash = bitcoin::hashes::sha256::Hash::hash(message);
        let message_hash = bitcoin::secp256k1::Message::from_digest(hash.to_byte_array());

        let signature = self.secp.sign_ecdsa(&message_hash, &private_key);
        Ok(signature.serialize_der().to_vec())
    }

    fn verify_message(&self, message: &[u8], signature: &[u8], path: &str) -> AnyaResult<bool> {
        let public_key = self.get_public_key(path)?;

        // Hash the message with SHA256
        let hash = bitcoin::hashes::sha256::Hash::hash(message);
        let message_hash = bitcoin::secp256k1::Message::from_digest(hash.to_byte_array());

        let signature = bitcoin::secp256k1::ecdsa::Signature::from_der(signature)
            .map_err(|e| BitcoinError::Wallet(format!("Invalid signature: {e}")))?;

        Ok(self
            .secp
            .verify_ecdsa(&message_hash, &signature, &public_key)
            .is_ok())
    }
}

impl AddressManager for Wallet {
    fn get_new_address(&self, address_type: AddressType) -> AnyaResult<Address> {
        let mut addresses = self
            .addresses
            .lock()
            .map_err(|e| format!("Mutex lock error: {e}"))?;

        let type_addresses = addresses.entry(address_type).or_insert_with(Vec::new);

        let index = type_addresses.len() as u32;

        let path = match address_type {
            AddressType::Legacy => format!("m/44'/0'/0'/0/{index}"),
            AddressType::SegWit => format!("m/84'/0'/0'/0/{index}"),
            AddressType::NestedSegWit => format!("m/49'/0'/0'/0/{index}"),
            AddressType::Taproot => format!("m/86'/0'/0'/0/{index}"),
        };

        let secret_key = self.derive_key(&path)?;
        let public_key = bitcoin::secp256k1::PublicKey::from_secret_key(&self.secp, &secret_key);

        // Convert to bitcoin::PublicKey
        let bitcoin_pubkey = bitcoin::PublicKey::new(public_key);
        // Get compressed public key for p2wpkh and p2shwpkh
        let compressed_pubkey =
            bitcoin::key::CompressedPublicKey::from_slice(&bitcoin_pubkey.inner.serialize())?;

        let address = match address_type {
            AddressType::Legacy => Address::p2pkh(bitcoin_pubkey, self.config.network),
            AddressType::SegWit => Address::p2wpkh(&compressed_pubkey, self.config.network),
            AddressType::NestedSegWit => Address::p2shwpkh(&compressed_pubkey, self.config.network),
            AddressType::Taproot => {
                let xonly = bitcoin::secp256k1::XOnlyPublicKey::from(public_key);
                Address::p2tr(&self.secp, xonly, None, self.config.network)
            }
        };

        type_addresses.push(address.clone());

        Ok(address)
    }

    fn get_address(&self, index: u32, address_type: AddressType) -> AnyaResult<Address> {
        let addresses = self
            .addresses
            .lock()
            .map_err(|e| format!("Mutex lock error: {e}"))?;

        if let Some(type_addresses) = addresses.get(&address_type) {
            if let Some(address) = type_addresses.get(index as usize) {
                return Ok(address.clone());
            }
        }

        // Address not found, derive it
        let path = match address_type {
            AddressType::Legacy => format!("m/44'/0'/0'/0/{index}"),
            AddressType::SegWit => format!("m/84'/0'/0'/0/{index}"),
            AddressType::NestedSegWit => format!("m/49'/0'/0'/0/{index}"),
            AddressType::Taproot => format!("m/86'/0'/0'/0/{index}"),
        };

        let secret_key = self.derive_key(&path)?;
        let public_key = bitcoin::secp256k1::PublicKey::from_secret_key(&self.secp, &secret_key);

        // Convert to bitcoin::PublicKey
        let bitcoin_pubkey = bitcoin::PublicKey::new(public_key);
        // Get compressed public key for p2wpkh and p2shwpkh
        let compressed_pubkey =
            bitcoin::key::CompressedPublicKey::from_slice(&bitcoin_pubkey.inner.serialize())?;

        let address = match address_type {
            AddressType::Legacy => Address::p2pkh(bitcoin_pubkey, self.config.network),
            AddressType::SegWit => Address::p2wpkh(&compressed_pubkey, self.config.network),
            AddressType::NestedSegWit => Address::p2shwpkh(&compressed_pubkey, self.config.network),
            AddressType::Taproot => {
                let xonly = bitcoin::secp256k1::XOnlyPublicKey::from(public_key);
                Address::p2tr(&self.secp, xonly, None, self.config.network)
            }
        };

        Ok(address)
    }

    fn is_address_mine(&self, address: &str) -> AnyaResult<bool> {
        let addresses = self
            .addresses
            .lock()
            .map_err(|e| format!("Mutex lock error: {e}"))?;

        for type_addresses in addresses.values() {
            for addr in type_addresses {
                if addr.to_string() == address {
                    return Ok(true);
                }
            }
        }

        Ok(false)
    }

    fn get_all_addresses(&self) -> AnyaResult<Vec<Address>> {
        let addresses = self
            .addresses
            .lock()
            .map_err(|e| format!("Mutex lock error: {e}"))?;

        let mut result = Vec::new();
        for type_addresses in addresses.values() {
            result.extend(type_addresses.clone());
        }

        Ok(result)
    }
}

impl TransactionManager for Wallet {
    fn create_transaction(
        &self,
        outputs: Vec<(String, u64)>,
        _fee_rate: f64,
        _options: transactions::TxOptions,
    ) -> AnyaResult<Transaction> {
        // Simplified implementation
        let mut tx_outs = Vec::new();

        for (addr, amount) in outputs {
            let script_pubkey = Address::from_str(&addr)
                .map_err(|e| BitcoinError::Wallet(format!("Invalid address: {e}")))?
                .require_network(self.config.network)
                .map_err(|e| BitcoinError::Wallet(format!("Network mismatch: {e}")))?
                .script_pubkey();

            tx_outs.push(TxOut {
                value: Amount::from_sat(amount),
                script_pubkey,
            });
        }

        // In a real implementation, we would select UTXOs, create inputs, etc.
        // For simplicity, we're returning a dummy transaction
        Ok(Transaction {
            version: bitcoin::transaction::Version(2),
            lock_time: LockTime::ZERO,
            input: vec![],
            output: tx_outs,
        })
    }

    fn sign_transaction(&self, _tx: &mut Transaction) -> AnyaResult<()> {
        // Simplified implementation
        Ok(())
    }

    fn broadcast_transaction(&self, tx: &Transaction) -> AnyaResult<String> {
        // Simplified implementation
        Ok(tx.compute_txid().to_string())
    }

    fn get_transaction(&self, _txid: &str) -> AnyaResult<Option<Transaction>> {
        // Simplified implementation
        Ok(None)
    }

    fn get_transactions(&self, _limit: usize, _offset: usize) -> AnyaResult<Vec<Transaction>> {
        // Simplified implementation
        Ok(vec![])
    }
}

impl BalanceManager for Wallet {
    fn get_balance(&self) -> AnyaResult<u64> {
        // Simplified implementation
        Ok(0)
    }

    fn get_unconfirmed_balance(&self) -> AnyaResult<u64> {
        // Simplified implementation
        Ok(0)
    }

    fn get_asset_balance(&self, asset_id: &str) -> AnyaResult<u64> {
        let assets = self
            .assets
            .lock()
            .map_err(|e| format!("Mutex lock error: {e}"))?;

        if let Some(asset) = assets.get(asset_id) {
            Ok(asset.balance)
        } else {
            Err(BitcoinError::Wallet(format!("Asset not found: {asset_id}")).into())
        }
    }

    fn get_all_asset_balances(&self) -> AnyaResult<HashMap<String, u64>> {
        let assets = self
            .assets
            .lock()
            .map_err(|e| format!("Mutex lock error: {e}"))?;

        let mut balances = HashMap::new();
        for (id, asset) in assets.iter() {
            balances.insert(id.clone(), asset.balance);
        }

        Ok(balances)
    }
}

impl UnifiedWallet for Wallet {
    fn name(&self) -> &str {
        &self.config.name
    }

    fn wallet_type(&self) -> WalletType {
        self.config.wallet_type.clone()
    }

    fn network(&self) -> Network {
        self.config.network
    }

    fn get_stacks_address(&self) -> AnyaResult<String> {
        // Derive a Stacks address from the same seed
        let secret_key = self.derive_key("m/44'/5757'/0'/0/0")?;

        // Convert the key to a Stacks address format
        // Note: This is a simplified implementation. Production would use proper Stacks address derivation
        let address_hash = format!(
            "{:x}",
            secret_key.secret_bytes()[0..20]
                .iter()
                .fold(0u64, |acc, &b| acc.wrapping_mul(256).wrapping_add(b as u64))
        );
        Ok(format!("ST{}", &address_hash[..32].to_uppercase()))
    }

    fn get_rsk_address(&self) -> AnyaResult<String> {
        // Derive an RSK address from the same seed
        let secret_key = self.derive_key("m/44'/137'/0'/0/0")?;

        // Convert the key to an RSK address format (Ethereum-style)
        // Note: This is a simplified implementation. Production would use proper RSK address derivation
        let public_key = bitcoin::secp256k1::PublicKey::from_secret_key(&self.secp, &secret_key);
        let address_bytes = &public_key.serialize()[1..]; // Remove 0x04 prefix
        let address_hash = format!(
            "{:02x}",
            address_bytes[0..20]
                .iter()
                .fold(0u64, |acc, &b| acc.wrapping_mul(256).wrapping_add(b as u64))
        );
        Ok(format!("0x{}", &address_hash[..40]))
    }

    fn get_liquid_address(&self) -> AnyaResult<String> {
        // Derive a Liquid address from the same seed
        let secret_key = self.derive_key("m/44'/2'/0'/0/0")?;

        // Convert the key to a Liquid address format (Elements/Confidential addresses)
        // Note: This is a simplified implementation. Production would use proper Liquid address derivation
        let public_key = bitcoin::secp256k1::PublicKey::from_secret_key(&self.secp, &secret_key);
        let address_bytes = &public_key.serialize()[1..]; // Remove 0x04 prefix
        let address_hash = format!(
            "{:02x}",
            address_bytes[0..25].iter().fold(0u128, |acc, &b| acc
                .wrapping_mul(256)
                .wrapping_add(b as u128))
        );
        Ok(format!("VT{}", &address_hash[..50]))
    }

    fn add_asset(&self, asset_id: &str, name: &str, asset_type: &str) -> AnyaResult<()> {
        let mut assets = self
            .assets
            .lock()
            .map_err(|e| format!("Mutex lock error: {e}"))?;

        if assets.contains_key(asset_id) {
            return Err(BitcoinError::Wallet(format!("Asset already exists: {asset_id}")).into());
        }

        let asset = Asset {
            id: asset_id.to_string(),
            name: name.to_string(),
            asset_type: asset_type.to_string(),
            chain: determine_chain_from_asset_id(asset_id),
            balance: 0,
            metadata: HashMap::new(),
        };

        assets.insert(asset_id.to_string(), asset);

        Ok(())
    }

    fn remove_asset(&self, asset_id: &str) -> AnyaResult<()> {
        let mut assets = self
            .assets
            .lock()
            .map_err(|e| format!("Mutex lock error: {e}"))?;

        if assets.remove(asset_id).is_none() {
            return Err(BitcoinError::Wallet(format!("Asset not found: {asset_id}")).into());
        }

        Ok(())
    }

    fn get_assets(&self) -> AnyaResult<Vec<Asset>> {
        let assets = self
            .assets
            .lock()
            .map_err(|e| format!("Mutex lock error: {e}"))?;
        Ok(assets.values().cloned().collect())
    }

    fn export_xpriv(&self, _password: &str) -> AnyaResult<String> {
        // Simplified implementation
        Err(BitcoinError::Wallet("Not implemented".to_string()).into())
    }

    fn import_xpriv(&self, _xpriv: &str, _password: &str) -> AnyaResult<()> {
        // Simplified implementation
        Err(BitcoinError::Wallet("Not implemented".to_string()).into())
    }

    fn backup(&self, _path: &str, _password: &str) -> AnyaResult<()> {
        // Simplified implementation
        Err(BitcoinError::Wallet("Not implemented".to_string()).into())
    }

    fn restore(&self, _path: &str, _password: &str) -> AnyaResult<()> {
        // Simplified implementation
        Err(BitcoinError::Wallet("Not implemented".to_string()).into())
    }
}

// Helper function to determine chain from asset ID
fn determine_chain_from_asset_id(asset_id: &str) -> String {
    // Simple heuristic based on asset ID prefix
    if asset_id.starts_with("btc-") {
        "Bitcoin".to_string()
    } else if asset_id.starts_with("lq-") {
        "Liquid".to_string()
    } else if asset_id.starts_with("rsk-") {
        "RSK".to_string()
    } else {
        "Unknown".to_string()
    }
}

/// Wallet error type
#[derive(Error, Debug)]
pub enum WalletError {
    /// Error related to the Bitcoin library
    #[error("Bitcoin error: {0}")]
    BitcoinError(String),

    /// Error related to secp256k1
    #[error("Secp256k1 error: {0}")]
    Secp256k1Error(#[from] secp256k1::Error),

    /// Error related to the BIP39 library
    #[error("BIP39 error: {0}")]
    Bip39Error(String),

    /// Error related to descriptors
    #[error("Descriptor error: {0}")]
    DescriptorError(String),

    /// Error related to wallet storage
    #[error("Wallet storage error: {0}")]
    StorageError(String),

    /// Error related to wallet configuration
    #[error("Wallet configuration error: {0}")]
    ConfigError(String),

    /// Error related to transaction creation
    #[error("Transaction creation error: {0}")]
    TransactionError(String),

    /// Error related to PSBT operations
    #[error("PSBT error: {0}")]
    PsbtError(String),

    /// Error related to signing operations
    #[error("Signing error: {0}")]
    SigningError(String),

    /// Error related to blockchain synchronization
    #[error("Synchronization error: {0}")]
    SyncError(String),

    /// Error related to address generation
    #[error("Address generation error: {0}")]
    AddressError(String),

    /// Error related to fee estimation
    #[error("Fee estimation error: {0}")]
    FeeEstimationError(String),

    /// RPC error
    #[error("RPC error: {0}")]
    RpcError(String),

    /// Invalid parameters
    #[error("Invalid parameters: {0}")]
    InvalidParameters(String),

    /// Insufficient funds
    #[error("Insufficient funds: {0}")]
    InsufficientFunds(String),

    /// IO error
    #[error("IO error: {0}")]
    IoError(#[from] std::io::Error),

    /// Serialization error
    #[error("Serialization error: {0}")]
    SerializationError(String),

    /// UTXO management error
    #[error("UTXO management error: {0}")]
    UtxoError(String),
}

/// UTXO (Unspent Transaction Output) representation
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct Utxo {
    /// The outpoint of this UTXO
    pub outpoint: OutPoint,

    /// The TxOut data
    pub txout: TxOut,

    /// The redeem script (if available)
    pub redeem_script: Option<ScriptBuf>,

    /// The witness script (if available)
    pub witness_script: Option<ScriptBuf>,

    /// Confirmations (0 for unconfirmed)
    pub confirmations: u32,

    /// Is this UTXO spendable (not locked or reserved)
    pub spendable: bool,

    /// Is this UTXO coming from the wallet (vs a watch-only address)
    pub from_wallet: bool,
}

/// Transaction information
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct TransactionInfo {
    /// Transaction ID
    pub txid: Txid,

    /// Complete transaction
    pub transaction: Transaction,

    /// Block height (None if unconfirmed)
    pub block_height: Option<u32>,

    /// Confirmations (0 for unconfirmed)
    pub confirmations: u32,

    /// Fee in satoshis
    pub fee: Option<u64>,

    /// Transaction time (from block)
    pub timestamp: Option<u64>,

    /// Our inputs value (sum of wallet inputs)
    pub sent: u64,

    /// Our outputs value (sum of wallet outputs)
    pub received: u64,

    /// Labels associated with this transaction
    pub labels: Vec<String>,
}

/// Fee rate type
#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
pub enum FeeRate {
    /// Satoshis per kilobyte
    SatPerKb(u64),

    /// Satoshis per virtual byte
    SatPerVb(u64),
}

impl FeeRate {
    /// Convert to satoshis per virtual byte
    pub fn to_sat_per_vb(&self) -> u64 {
        match self {
            FeeRate::SatPerKb(fee) => (fee + 999) / 1000,
            FeeRate::SatPerVb(fee) => *fee,
        }
    }

    /// Convert to satoshis per kilobyte
    pub fn to_sat_per_kb(&self) -> u64 {
        match self {
            FeeRate::SatPerKb(fee) => *fee,
            FeeRate::SatPerVb(fee) => fee * 1000,
        }
    }
}

/// Wallet synchronization state
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct SyncState {
    /// Latest known block height
    pub block_height: u32,

    /// Latest known block hash
    pub block_hash: String,

    /// Latest scan time
    pub last_scan: u64,

    /// Sync progress (0.0 to 1.0)
    pub progress: f64,

    /// Is initial block download still in progress
    pub ibd: bool,
}

/// Wallet trait definition
#[async_trait]
pub trait WalletTrait: Send + Sync {
    /// Initialize the wallet
    async fn init(&self) -> Result<(), WalletError>;

    /// Generate a new receiving address
    async fn get_new_address(&self) -> Result<Address, WalletError>;

    /// Get the current receiving address (without incrementing)
    async fn get_current_address(&self) -> Result<Address, WalletError>;

    /// Get a change address
    async fn get_change_address(&self) -> Result<Address, WalletError>;

    /// Check if an address belongs to this wallet
    async fn is_mine(&self, address: &Address) -> Result<bool, WalletError>;

    /// Get all wallet addresses
    async fn list_addresses(&self) -> Result<Vec<Address>, WalletError>;

    /// Get wallet balance
    async fn get_balance(&self) -> Result<u64, WalletError>;

    /// Get wallet balance with details
    async fn get_detailed_balance(&self) -> Result<(u64, u64, u64), WalletError>;

    /// List unspent UTXOs
    async fn list_utxos(&self) -> Result<Vec<Utxo>, WalletError>;

    /// Get transaction history
    async fn get_transactions(&self) -> Result<Vec<TransactionInfo>, WalletError>;

    /// Get transaction by ID
    async fn get_transaction(&self, txid: &Txid) -> Result<Option<TransactionInfo>, WalletError>;

    /// Create a transaction
    async fn create_transaction(&self, params: TransactionParams) -> Result<PSBT, WalletError>;

    /// Sign a transaction
    async fn sign_transaction(&self, psbt: &mut PSBT) -> Result<bool, WalletError>;

    /// Broadcast a transaction
    async fn broadcast_transaction(&self, transaction: &Transaction) -> Result<Txid, WalletError>;

    /// Get fee estimate for the given strategy
    async fn get_fee_rate(&self, strategy: FeeStrategy) -> Result<FeeRate, WalletError>;

    /// Calculate fee for a transaction
    async fn calculate_fee(&self, psbt: &PSBT) -> Result<u64, WalletError>;

    /// Synchronize the wallet with the blockchain
    async fn sync(&self) -> Result<SyncState, WalletError>;

    /// Export wallet data
    async fn export(&self, path: &Path) -> Result<(), WalletError>;

    /// Import wallet data
    async fn import(&self, path: &Path) -> Result<(), WalletError>;

    /// Create backup
    async fn backup(&self, path: &Path) -> Result<(), WalletError>;

    /// Get wallet information
    async fn get_info(&self) -> Result<WalletInfo, WalletError>;
}

/// Wallet info
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct WalletInfo {
    /// Wallet name
    pub name: String,

    /// Wallet version
    pub version: String,

    /// Wallet format
    pub format: String,

    /// Network
    pub network: Network,

    /// Current balance
    pub balance: u64,

    /// Unconfirmed balance
    pub unconfirmed_balance: u64,

    /// Immature balance
    pub immature_balance: u64,

    /// Number of keys
    pub keypools: u32,

    /// Number of transactions
    pub tx_count: u32,

    /// Keypool oldest
    pub keypool_oldest: u64,

    /// Keypool size
    pub keypool_size: u32,

    /// Payee requires witness
    pub private_keys_enabled: bool,

    /// Unlocked until
    pub unlocked_until: Option<u64>,

    /// HD seed version
    pub hdseedid: Option<String>,

    /// Is the wallet avoiding reuse
    pub avoid_reuse: bool,

    /// Scanning status
    pub scanning: bool,

    /// Descriptors enabled
    pub descriptors: bool,
}

/// Bitcoin wallet implementation
pub struct BitcoinWallet {
    /// Wallet configuration
    #[allow(dead_code)]
    // Required for future wallet extensibility and compliance (see docs/INDEX_CORRECTED.md)
    config: WalletConfig,

    /// Wallet data storage
    #[allow(dead_code)] // Required for future storage backends (see docs/INDEX_CORRECTED.md)
    storage: Arc<Mutex<WalletStorage>>,

    /// Secp256k1 context
    #[allow(dead_code)]
    // Required for future cryptographic operations (see docs/research/PROTOCOL_UPGRADES.md)
    secp: Secp256k1<bitcoin::secp256k1::All>,
}

/// Wallet storage structure
#[derive(Debug, Serialize, Deserialize)]
struct WalletStorage {
    /// Wallet metadata
    metadata: WalletMetadata,

    /// UTXOs
    utxos: HashMap<OutPoint, Utxo>,

    /// Transactions
    transactions: HashMap<Txid, TransactionInfo>,

    /// Address index mapping
    addresses: HashMap<String, AddressInfo>,

    /// Current indexes
    indexes: WalletIndexes,
}

/// Wallet metadata
#[derive(Debug, Clone, Serialize, Deserialize)]
struct WalletMetadata {
    /// Wallet creation time
    created_at: u64,

    /// Wallet last updated
    updated_at: u64,

    /// Wallet version
    version: String,

    /// Wallet network
    network: Network,

    /// Wallet master fingerprint
    master_fingerprint: Option<[u8; 4]>,

    /// Labels
    labels: HashMap<String, String>,
}

/// Wallet address information
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct AddressInfo {
    /// The address string
    pub address: String,
    /// The path from which this address was derived
    path: Option<DerivationPath>,
    /// The script
    script: ScriptBuf,
    /// Is this a change address
    is_change: bool,
    /// Index in the derivation sequence
    index: u32,
    /// The address labels
    labels: Vec<String>,
    /// Last time this address was used
    last_used: Option<u64>,
}

/// Wallet index tracking
#[derive(Debug, Clone, Serialize, Deserialize)]
struct WalletIndexes {
    /// Next receive address index
    receive_index: u32,

    /// Next change address index
    change_index: u32,

    /// Last synced block
    last_block: Option<u32>,

    /// Last sync time
    last_sync: Option<u64>,
}

/// Fee strategy
#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
pub enum FeeStrategy {
    /// Very low fee (might take long to confirm)
    VeryLow,

    /// Low fee
    Low,

    /// Medium fee (good balance)
    Medium,

    /// High fee
    High,

    /// Very high fee (for urgent transactions)
    VeryHigh,

    /// Custom fee rate
    Custom(FeeRate),
}

/// Transaction creation parameters
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct TransactionParams {
    /// List of recipients with amounts
    pub recipients: Vec<(String, u64)>,

    /// Optional coin selection (use specific UTXOs)
    pub utxos: Option<Vec<OutPoint>>,

    /// Fee strategy
    pub fee_strategy: Option<FeeStrategy>,

    /// Lock time
    pub lock_time: Option<u32>,

    /// Enable RBF (Replace-By-Fee)
    pub enable_rbf: bool,

    /// Optional change address (if not using the default)
    pub change_address: Option<String>,

    /// Include metadata in an OP_RETURN output
    pub op_return_data: Option<Vec<u8>>,

    /// Allow spending unconfirmed UTXOs
    pub allow_unconfirmed: bool,
}

/// Coin selection strategy
#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
pub enum CoinSelectionStrategy {
    /// Select largest UTXOs first
    LargestFirst,

    /// Select smallest UTXOs first
    SmallestFirst,

    /// Use oldest confirmed first
    OldestFirst,

    /// Use random selection
    Random,

    /// Optimize for privacy (avoid change)
    PrivacyOptimized,

    /// Branch and bound algorithm
    BranchAndBound,
}

// Copyright (C) 2023-2025 Anya Project Contributors
// Last Modified: 2025-05-30