anya-core 1.2.0

use crate::monitoring::metrics;

/// Transaction validation errors
#[derive(Debug)]
pub enum ValidationError {
    InvalidStructure,
    MissingWitness,
    TaprootViolation,
    ScriptError,
}

/// Validates a transaction according to Bitcoin protocol rules
/// 
/// # Arguments
/// * `tx_bytes` - Raw transaction bytes
/// 
/// # Returns
/// * `Ok(())` if validation passes
/// * `Err(ValidationError)` if validation fails
pub fn validate_transaction(tx_bytes: &[u8]) -> Result<(), ValidationError> {
    // Validate transaction structure
    if !is_valid_structure(tx_bytes) {
        return Err(ValidationError::InvalidStructure);
    }
    
    // Check for SegWit (required)
    if !has_witness(tx_bytes) {
        return Err(ValidationError::MissingWitness);
    }
    
    // Check Taproot conditions (BIP 341)
    if !check_taproot_conditions(tx_bytes) {
        return Err(ValidationError::TaprootViolation);
    }
    
    // Register metrics
    metrics::register_bip_compliance("341", true);
    
    Ok(())
}

/// Checks if transaction has a valid structure
fn is_valid_structure(tx_bytes: &[u8]) -> bool {
    // Implementation would parse transaction and validate structure
    // This is a placeholder - actual implementation would use Bitcoin libraries
    true
}

/// Checks if transaction has witness data
fn has_witness(tx_bytes: &[u8]) -> bool {
    // Implementation would check for witness data
    // This is a placeholder - actual implementation would use Bitcoin libraries
    true
}

/// Checks if transaction complies with Taproot rules (BIP 341)
fn check_taproot_conditions(tx_bytes: &[u8]) -> bool {
    // Implementation would validate against Taproot rules
    // This is a placeholder - actual implementation would use Bitcoin libraries
    true
}

#[cfg(test)]
mod tests {
    use super::*;
    
    #[test]
    fn test_valid_transaction() {
        let dummy_tx = vec![0u8; 100]; // Placeholder
        
        // Should pass validation
        assert!(validate_transaction(&dummy_tx).is_ok());
    }
    
    #[test]
    fn test_invalid_transaction() {
        // Test would be implemented with invalid transaction data
        // This test is a placeholder
    }
}