//! Error types for PIDDM demo.

use serde::{Deserialize, Serialize};
use thiserror::Error;

/// Errors that can occur in the PIDDM demo.
#[derive(Debug, Clone, Error, Serialize, Deserialize)]
pub enum PiddmError {
    /// Invalid configuration parameter.
    #[error("Invalid configuration: {0}")]
    InvalidConfig(String),

    /// Training error.
    #[error("Training error: {0}")]
    TrainingError(String),

    /// Sampling/inference error.
    #[error("Sampling error: {0}")]
    SamplingError(String),

    /// Model not loaded.
    #[error("Model not loaded")]
    ModelNotLoaded,

    /// IO error.
    #[error("IO error: {0}")]
    IoError(String),

    /// Backend error.
    #[error("Backend error: {0}")]
    BackendError(String),
}

/// Result type for PIDDM operations.
pub type PiddmResult<T> = Result<T, PiddmError>;

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_error_display() {
        let err = PiddmError::InvalidConfig("bad value".to_string());
        assert!(err.to_string().contains("Invalid configuration"));
    }
}