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/// Error types for the pocx_hashlib crate
use std::fmt;

/// Main error type for PoC hash library operations
#[derive(Debug, Clone, PartialEq)]
pub enum PoCXHashError {
    /// Memory allocation failure
    AllocationError(String),
    /// Buffer size validation error
    BufferSizeError(String),
    /// Invalid input parameters
    InvalidInput(String),
    /// Hexadecimal decoding error
    HexDecodeError(String),
    /// Layout creation error for page alignment
    LayoutError(String),
}

impl fmt::Display for PoCXHashError {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        match self {
            PoCXHashError::AllocationError(msg) => write!(f, "Memory allocation failed: {}", msg),
            PoCXHashError::BufferSizeError(msg) => write!(f, "Buffer size error: {}", msg),
            PoCXHashError::InvalidInput(msg) => write!(f, "Invalid input: {}", msg),
            PoCXHashError::HexDecodeError(msg) => write!(f, "Hex decode error: {}", msg),
            PoCXHashError::LayoutError(msg) => write!(f, "Layout error: {}", msg),
        }
    }
}

impl std::error::Error for PoCXHashError {}

/// Conversion from hex::FromHexError to PoCXHashError
impl From<hex::FromHexError> for PoCXHashError {
    fn from(err: hex::FromHexError) -> Self {
        PoCXHashError::HexDecodeError(err.to_string())
    }
}

/// Result type alias for convenience
pub type Result<T> = std::result::Result<T, PoCXHashError>;
