anya-core 1.2.0

//! Bitcoin HSM Provider Implementation
//! [AIR-3][AIS-3][AIT-3][AIP-3][RES-3]
//! This module provides a Bitcoin-specific HSM implementation for secure key management
//! with hardware wallets and other specialized Bitcoin hardware security modules.

use async_trait::async_trait;
use base64::Engine;
use chrono::Utc;
use serde::{Deserialize, Serialize};
use serde_json::json;
use std::collections::HashMap;
use tokio::sync::Mutex;
use tracing::{debug, info};
use uuid::Uuid;

use bitcoin::{
    bip32::{DerivationPath, Xpriv as ExtendedPrivKey, Xpub as ExtendedPubKey},
    hashes::{sha256, Hash},
    secp256k1::{ecdsa::Signature, Message, PublicKey as SepcPublicKey, Secp256k1, SecretKey},
    Network,
};

use crate::security::hsm::config::BitcoinConfig;
use crate::security::hsm::error::HsmError;
use crate::security::hsm::provider::{
    HsmOperation, HsmProvider, HsmProviderStatus, HsmRequest, HsmResponse, KeyGenParams, KeyInfo,
    KeyPair, KeyType, SigningAlgorithm,
};

/// Bitcoin HSM Provider
#[derive(Debug)]
pub struct BitcoinHsmProvider {
    /// Network
    network: Network,

    /// Secp context
    secp: Secp256k1<bitcoin::secp256k1::All>,

    /// Keys
    keys: Mutex<HashMap<String, KeyInfo>>,

    /// Provider status
    status: Mutex<HsmProviderStatus>,

    /// Master seed (in a real implementation, this would be stored in secure hardware)
    /// WARNING: This is only for simulation/development
    master_seed: [u8; 32],

    /// Master extended key (derived from seed)
    master_xpriv: Mutex<Option<bitcoin::bip32::Xpriv>>,

    /// Master extended public key
    master_xpub: Mutex<Option<bitcoin::bip32::Xpub>>,
}

impl BitcoinHsmProvider {
    /// Create a new BitcoinHsmProvider
    pub async fn new(config: &BitcoinConfig) -> Result<Self, HsmError> {
        info!("Initializing Bitcoin HSM Provider");

        // Determine the network
        let network = match config.network {
            crate::security::hsm::config::BitcoinNetworkType::Mainnet => Network::Bitcoin,
            crate::security::hsm::config::BitcoinNetworkType::Testnet => Network::Testnet,
            crate::security::hsm::config::BitcoinNetworkType::Regtest => Network::Regtest,
            crate::security::hsm::config::BitcoinNetworkType::Signet => Network::Signet,
        };

        // Create a dummy seed for development/testing
        // In a real implementation, this would be securely generated and stored
        let mut master_seed = [0u8; 32];
        getrandom::fill(&mut master_seed).map_err(|e| {
            HsmError::ProviderError(format!("Failed to generate random seed: {}", e))
        })?;

        let secp = Secp256k1::new();

        let provider = Self {
            network,
            secp,
            keys: Mutex::new(HashMap::new()),
            status: Mutex::new(HsmProviderStatus::Initializing),
            master_seed,
            master_xpriv: Mutex::new(None),
            master_xpub: Mutex::new(None),
        };

        Ok(provider)
    }

    /// Derive a key from the master seed at the given derivation path
    async fn derive_key(&self, path: &str) -> Result<(SecretKey, SepcPublicKey), HsmError> {
        let derivation_path = path
            .parse::<DerivationPath>()
            .map_err(|e| HsmError::InvalidParameters(format!("Invalid derivation path: {}", e)))?;

        let master_xpriv_lock = self.master_xpriv.lock().await;
        let master_xpriv = master_xpriv_lock
            .as_ref()
            .ok_or_else(|| HsmError::ProviderError("Master key not initialized".to_string()))?;

        let derived_xpriv = master_xpriv
            .derive_priv(&self.secp, &derivation_path)
            .map_err(|e| HsmError::ProviderError(format!("Failed to derive private key: {}", e)))?;

        // Get the private key bytes
        let secret_key = derived_xpriv.private_key;
        // Convert to a SecretKey - in newer versions of bitcoin, we need to use the secret_bytes method
        let secret_bytes = secret_key.secret_bytes();
        let secret_key = SecretKey::from_slice(&secret_bytes)
            .map_err(|e| HsmError::ProviderError(format!("Invalid secret key: {}", e)))?;
        let public_key = secret_key.public_key(&self.secp);

        Ok((secret_key, public_key))
    }

    /// Generate a key pair and store it
    async fn generate_bitcoin_key(&self, params: &KeyGenParams) -> Result<KeyPair, HsmError> {
        // Use the params attributes to get the derivation path or generate a new one
        let derivation_path = params
            .attributes
            .get("derivation_path")
            .cloned()
            .unwrap_or_else(|| format!("m/84'/0'/0'/0/{}", rand::random::<u32>() % 1000));

        let (secret_key, public_key) = self.derive_key(&derivation_path).await?;

        // Create a key ID
        let key_id = params
            .id
            .clone()
            .unwrap_or_else(|| Uuid::new_v4().to_string());

        // Create key info
        let key_info = KeyInfo {
            id: key_id.clone(),
            label: params.label.clone(),
            key_type: params.key_type.clone(),
            extractable: params.extractable,
            usages: params.usages.clone(),
            created_at: Utc::now(),
            expires_at: params.expires_at,
            attributes: {
                let mut attributes = params.attributes.clone();
                attributes.insert("derivation_path".to_string(), derivation_path);
                attributes
            },
        };

        // Store key info
        let mut keys = self.keys.lock().await;
        keys.insert(key_id.clone(), key_info);

        // Create key pair
        let public_key_bytes = public_key.serialize().to_vec();

        let key_pair = KeyPair {
            id: key_id,
            key_type: params.key_type.clone(),
            public_key: public_key_bytes,
            private_key_handle: format!("sk:{}", hex::encode(secret_key.secret_bytes())),
        };

        Ok(key_pair)
    }

    /// Sign data with a Bitcoin key
    async fn sign_bitcoin(
        &self,
        key_id: &str,
        data: &[u8],
        algorithm: SigningAlgorithm,
    ) -> Result<Vec<u8>, HsmError> {
        // Get key info
        let keys = self.keys.lock().await;
        let key_info = keys
            .get(key_id)
            .ok_or_else(|| HsmError::KeyNotFound(format!("Key not found: {}", key_id)))?;

        // Get derivation path
        let derivation_path = key_info
            .attributes
            .get("derivation_path")
            .ok_or_else(|| HsmError::ProviderError("Derivation path not found".to_string()))?;

        // Derive key
        let (secret_key, _) = self.derive_key(derivation_path).await?;

        // Create message to sign
        let message = match algorithm {
            SigningAlgorithm::EcdsaSha256 => {
                let hash = sha256::Hash::hash(data);
                Message::from_digest_slice(hash.as_ref())
                    .map_err(|e| HsmError::ProviderError(format!("Invalid message: {}", e)))?
            }
            _ => {
                return Err(HsmError::InvalidParameters(format!(
                    "Unsupported algorithm: {:?}",
                    algorithm
                )))
            }
        };

        // Sign message
        let signature = self.secp.sign_ecdsa(&message, &secret_key);

        Ok(signature.serialize_der().to_vec())
    }

    /// Verify a signature with a Bitcoin key
    async fn verify_bitcoin(
        &self,
        key_id: &str,
        data: &[u8],
        signature: &[u8],
        algorithm: SigningAlgorithm,
    ) -> Result<bool, HsmError> {
        // Get key info
        let keys = self.keys.lock().await;
        let key_info = keys
            .get(key_id)
            .ok_or_else(|| HsmError::KeyNotFound(format!("Key not found: {}", key_id)))?;

        // Get derivation path
        let derivation_path = key_info
            .attributes
            .get("derivation_path")
            .ok_or_else(|| HsmError::ProviderError("Derivation path not found".to_string()))?;

        // Derive key
        let (_, public_key) = self.derive_key(derivation_path).await?;

        // Create message to verify
        let message = match algorithm {
            SigningAlgorithm::EcdsaSha256 => {
                let hash = sha256::Hash::hash(data);
                Message::from_digest_slice(hash.as_ref())
                    .map_err(|e| HsmError::ProviderError(format!("Invalid message: {}", e)))?
            }
            _ => {
                return Err(HsmError::InvalidParameters(format!(
                    "Unsupported algorithm: {:?}",
                    algorithm
                )))
            }
        };

        // Parse signature
        let signature = Signature::from_der(signature)
            .map_err(|e| HsmError::ProviderError(format!("Invalid signature: {}", e)))?;

        // Verify signature
        let result = self
            .secp
            .verify_ecdsa(&message, &signature, &public_key)
            .is_ok();

        Ok(result)
    }
}

#[async_trait]
impl HsmProvider for BitcoinHsmProvider {
    async fn initialize(&self) -> Result<(), HsmError> {
        info!("Initializing Bitcoin HSM Provider");

        // Set status to initializing
        let mut status = self.status.lock().await;
        *status = HsmProviderStatus::Initializing;

        // Initialize master keys
        let master_xpriv = ExtendedPrivKey::new_master(self.network, &self.master_seed)
            .map_err(|e| HsmError::ProviderError(format!("Failed to create master key: {}", e)))?;

        let master_xpub = ExtendedPubKey::from_priv(&self.secp, &master_xpriv);

        // Store master keys
        let mut master_xpriv_lock = self.master_xpriv.lock().await;
        *master_xpriv_lock = Some(master_xpriv);
        drop(master_xpriv_lock);

        let mut master_xpub_lock = self.master_xpub.lock().await;
        *master_xpub_lock = Some(master_xpub);
        drop(master_xpub_lock);

        // Set status to ready
        *status = HsmProviderStatus::Ready;

        info!("Bitcoin HSM Provider initialized successfully");
        Ok(())
    }

    async fn generate_key(&self, params: KeyGenParams) -> Result<(KeyPair, KeyInfo), HsmError> {
        debug!("Generating key with params: {:?}", params);

        // Check provider status
        let status = self.status.lock().await;
        if *status != HsmProviderStatus::Ready {
            return Err(HsmError::ProviderError(format!(
                "Provider not ready: {:?}",
                *status
            )));
        }
        drop(status);

        // Check key type
        let key_pair = match &params.key_type {
            KeyType::Ec { curve }
                if *curve == crate::security::hsm::provider::EcCurve::Secp256k1 =>
            {
                self.generate_bitcoin_key(&params).await?
            }
            _ => {
                return Err(HsmError::InvalidParameters(format!(
                    "Unsupported key type: {:?}",
                    params.key_type
                )))
            }
        };

        // Create key info
        let key_info = KeyInfo {
            id: params
                .id
                .clone()
                .unwrap_or_else(|| Uuid::new_v4().to_string()),
            key_type: params.key_type.clone(),
            attributes: params.attributes.clone(),
            created_at: Utc::now(),
            expires_at: params.expires_at,
            usages: params.usages.clone(),
            extractable: params.extractable,
            label: params.label.clone(),
        };

        Ok((key_pair, key_info))
    }

    async fn sign(
        &self,
        key_id: &str,
        algorithm: SigningAlgorithm,
        data: &[u8],
    ) -> Result<Vec<u8>, HsmError> {
        debug!(
            "Signing data with key {}, algorithm {:?}",
            key_id, algorithm
        );

        // Check provider status
        let status = self.status.lock().await;
        if *status != HsmProviderStatus::Ready {
            return Err(HsmError::ProviderError(format!(
                "Provider not ready: {:?}",
                *status
            )));
        }
        drop(status);

        self.sign_bitcoin(key_id, data, algorithm).await
    }

    async fn verify(
        &self,
        key_id: &str,
        algorithm: SigningAlgorithm,
        data: &[u8],
        signature: &[u8],
    ) -> Result<bool, HsmError> {
        debug!(
            "Verifying signature with key {}, algorithm {:?}",
            key_id, algorithm
        );

        // Check provider status
        let status = self.status.lock().await;
        if *status != HsmProviderStatus::Ready {
            return Err(HsmError::ProviderError(format!(
                "Provider not ready: {:?}",
                *status
            )));
        }
        drop(status);

        self.verify_bitcoin(key_id, data, signature, algorithm)
            .await
    }

    async fn export_public_key(&self, key_id: &str) -> Result<Vec<u8>, HsmError> {
        debug!("Exporting public key {}", key_id);

        // Check provider status
        let status = self.status.lock().await;
        if *status != HsmProviderStatus::Ready {
            return Err(HsmError::ProviderError(format!(
                "Provider not ready: {:?}",
                *status
            )));
        }
        drop(status);

        // Get key info
        let keys = self.keys.lock().await;
        let key_info = keys
            .get(key_id)
            .ok_or_else(|| HsmError::KeyNotFound(format!("Key not found: {}", key_id)))?;

        // Get derivation path
        let derivation_path = key_info
            .attributes
            .get("derivation_path")
            .ok_or_else(|| HsmError::ProviderError("Derivation path not found".to_string()))?;

        // Derive key
        let (_, public_key) = self.derive_key(derivation_path).await?;

        Ok(public_key.serialize().to_vec())
    }

    async fn list_keys(&self) -> Result<Vec<KeyInfo>, HsmError> {
        debug!("Listing keys");

        // Check provider status
        let status = self.status.lock().await;
        if *status != HsmProviderStatus::Ready {
            return Err(HsmError::ProviderError(format!(
                "Provider not ready: {:?}",
                *status
            )));
        }
        drop(status);

        // Get all keys
        let keys = self.keys.lock().await;
        let keys_list = keys.values().cloned().collect();

        Ok(keys_list)
    }

    async fn delete_key(&self, key_id: &str) -> Result<(), HsmError> {
        debug!("Deleting key {}", key_id);

        // Check provider status
        let status = self.status.lock().await;
        if *status != HsmProviderStatus::Ready {
            return Err(HsmError::ProviderError(format!(
                "Provider not ready: {:?}",
                *status
            )));
        }
        drop(status);

        // Delete key
        let mut keys = self.keys.lock().await;
        if keys.remove(key_id).is_none() {
            return Err(HsmError::KeyNotFound(format!("Key not found: {}", key_id)));
        }

        Ok(())
    }

    async fn get_status(&self) -> Result<HsmProviderStatus, HsmError> {
        let status = self.status.lock().await;
        Ok(status.clone())
    }

    async fn close(&self) -> Result<(), HsmError> {
        debug!("Closing Bitcoin HSM Provider");

        // Set status to shutting down
        let mut status = self.status.lock().await;
        *status = HsmProviderStatus::Unavailable;

        // Clear master keys
        let mut master_xpriv_lock = self.master_xpriv.lock().await;
        *master_xpriv_lock = None;
        drop(master_xpriv_lock);

        let mut master_xpub_lock = self.master_xpub.lock().await;
        *master_xpub_lock = None;
        drop(master_xpub_lock);

        Ok(())
    }

    async fn execute_operation(&self, request: HsmRequest) -> Result<HsmResponse, HsmError> {
        debug!("Executing operation: {:?}", request.operation);

        match request.operation {
            HsmOperation::GenerateKey => {
                let params: KeyGenParams = serde_json::from_value(request.parameters.clone())
                    .map_err(|e| {
                        HsmError::InvalidParameters(format!("Invalid parameters: {}", e))
                    })?;

                let (key_pair, key_info) = self.generate_key(params).await?;

                Ok(HsmResponse::success(
                    request.id,
                    Some(json!({
                        "key_pair": key_pair,
                        "key_info": key_info
                    })),
                ))
            }
            HsmOperation::Sign => {
                let params = serde_json::from_value::<SignParams>(request.parameters.clone())
                    .map_err(|e| {
                        HsmError::InvalidParameters(format!("Invalid parameters: {}", e))
                    })?;

                // [AIR-3][AIS-3][BPC-3][RES-3] Use base64 Engine for encoding/decoding
                // This follows official Bitcoin Improvement Proposals (BIPs) standards for secure data handling
                let data = base64::engine::general_purpose::STANDARD
                    .decode(&params.data)
                    .map_err(|e| HsmError::InvalidParameters(format!("Invalid data: {}", e)))?;

                let signature = self.sign(&params.key_name, params.algorithm, &data).await?;

                Ok(HsmResponse::success(
                    request.id,
                    Some(json!({
                        "signature": base64::engine::general_purpose::STANDARD.encode(signature)
                    })),
                ))
            }
            HsmOperation::Verify => {
                let params = serde_json::from_value::<VerifyParams>(request.parameters.clone())
                    .map_err(|e| {
                        HsmError::InvalidParameters(format!("Invalid parameters: {}", e))
                    })?;

                // [AIR-3][AIS-3][BPC-3][RES-3] Use base64 Engine for encoding/decoding
                // This follows official Bitcoin Improvement Proposals (BIPs) standards for secure data handling
                let data = base64::engine::general_purpose::STANDARD
                    .decode(&params.data)
                    .map_err(|e| HsmError::InvalidParameters(format!("Invalid data: {}", e)))?;

                let signature = base64::engine::general_purpose::STANDARD
                    .decode(&params.signature)
                    .map_err(|e| {
                        HsmError::InvalidParameters(format!("Invalid signature: {}", e))
                    })?;

                let valid = self
                    .verify(&params.key_name, params.algorithm, &data, &signature)
                    .await?;

                Ok(HsmResponse::success(
                    request.id,
                    Some(json!({
                        "valid": valid
                    })),
                ))
            }
            HsmOperation::ExportPublicKey => {
                let params = serde_json::from_value::<GetKeyParams>(request.parameters.clone())
                    .map_err(|e| {
                        HsmError::InvalidParameters(format!("Invalid parameters: {}", e))
                    })?;

                let public_key = self.export_public_key(&params.key_name).await?;

                // [AIR-3][AIS-3][BPC-3][RES-3] Use base64 Engine for encoding
                // This follows official Bitcoin Improvement Proposals (BIPs) standards for secure data handling
                Ok(HsmResponse::success(
                    request.id,
                    Some(json!({
                        "public_key": base64::engine::general_purpose::STANDARD.encode(public_key)
                    })),
                ))
            }
            HsmOperation::ListKeys => {
                let keys = self.list_keys().await?;

                Ok(HsmResponse::success(
                    request.id,
                    Some(json!({
                        "keys": keys
                    })),
                ))
            }
            HsmOperation::DeleteKey => {
                let params = serde_json::from_value::<DeleteKeyParams>(request.parameters.clone())
                    .map_err(|e| {
                        HsmError::InvalidParameters(format!("Invalid parameters: {}", e))
                    })?;

                self.delete_key(&params.key_name).await?;

                Ok(HsmResponse::success(request.id, None))
            }
            _ => Err(HsmError::InvalidParameters(format!(
                "Unsupported operation: {:?}",
                request.operation
            ))),
        }
    }
}

// Parameter structs for operations

/// Parameters for signing
#[derive(Serialize, Deserialize, Debug)]
struct SignParams {
    /// Key name
    pub key_name: String,

    /// Data to sign (base64 encoded)
    pub data: String,

    /// Signing algorithm
    pub algorithm: SigningAlgorithm,
}

/// Parameters for verifying
#[derive(Serialize, Deserialize, Debug)]
struct VerifyParams {
    /// Key name
    pub key_name: String,

    /// Data to verify (base64 encoded)
    pub data: String,

    /// Signature to verify (base64 encoded)
    pub signature: String,

    /// Signing algorithm
    pub algorithm: SigningAlgorithm,
}

/// Parameters for getting a key
#[derive(Serialize, Deserialize, Debug)]
struct GetKeyParams {
    /// Key name
    pub key_name: String,
}

/// Parameters for deleting a key
#[derive(Serialize, Deserialize, Debug)]
struct DeleteKeyParams {
    /// Key name
    pub key_name: String,
}