use thiserror::Error;

/// Errors that can occur in Graph Neural Network operations
#[derive(Error, Debug, Clone, PartialEq)]
pub enum GeomError {
    #[error("Invalid node ID: {0}")]
    InvalidNodeId(usize),

    #[error("Invalid edge ID: {0}")]
    InvalidEdgeId(usize),

    #[error("Node not found: {0}")]
    NodeNotFound(usize),

    #[error("Edge not found: {0}")]
    EdgeNotFound(usize),

    #[error("Graph is empty")]
    EmptyGraph,

    #[error("Dimension mismatch: expected {expected}, got {actual}")]
    DimensionMismatch { expected: usize, actual: usize },

    #[error("Feature shape mismatch: expected {expected:?}, got {actual:?}")]
    FeatureShapeMismatch {
        expected: Vec<usize>,
        actual: Vec<usize>,
    },

    #[error("Layer initialization failed: {reason}")]
    LayerInitializationFailed { reason: String },

    #[error("Forward pass failed: {reason}")]
    ForwardPassFailed { reason: String },

    #[error("Backward pass failed: {reason}")]
    BackwardPassFailed { reason: String },

    #[error("Message passing failed: {reason}")]
    MessagePassingFailed { reason: String },

    #[error("Aggregation failed: {reason}")]
    AggregationFailed { reason: String },

    #[error("Tensor operation error: {0}")]
    TensorError(#[from] rtx_tensor::TensorError),

    #[error("Runtime error: {0}")]
    RuntimeError(String),
}

impl From<anyhow::Error> for GeomError {
    fn from(error: anyhow::Error) -> Self {
        Self::RuntimeError(error.to_string())
    }
}

pub type Result<T> = std::result::Result<T, GeomError>;