relay-knowledge 1.1.16

use serde::{Deserialize, Serialize};

use super::ApiMetadata;

/// Stable error categories used across interface adapters.
#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
#[serde(rename_all = "snake_case")]
pub enum ErrorKind {
    InvalidArgument,
    StorageUnavailable,
    QosRejected,
    Timeout,
    Internal,
}

/// API error shape suitable for JSON and streaming output.
#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
pub struct ApiError {
    pub error_kind: ErrorKind,
    pub message: String,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub metadata: Option<ApiMetadata>,
}

impl ApiError {
    /// Creates an invalid argument error.
    pub fn invalid_argument(message: impl Into<String>) -> Self {
        Self {
            error_kind: ErrorKind::InvalidArgument,
            message: message.into(),
            metadata: None,
        }
    }

    /// Creates a storage boundary error without exposing backend internals.
    pub fn storage_unavailable(message: impl Into<String>) -> Self {
        Self {
            error_kind: ErrorKind::StorageUnavailable,
            message: message.into(),
            metadata: None,
        }
    }

    /// Creates a QoS admission error for bounded overload responses.
    pub fn qos_rejected(message: impl Into<String>) -> Self {
        Self {
            error_kind: ErrorKind::QosRejected,
            message: message.into(),
            metadata: None,
        }
    }

    /// Creates a bounded-operation timeout error.
    pub fn timeout(message: impl Into<String>) -> Self {
        Self {
            error_kind: ErrorKind::Timeout,
            message: message.into(),
            metadata: None,
        }
    }

    /// Creates an internal consistency error that is not attributable to user input.
    pub fn internal(message: impl Into<String>) -> Self {
        Self {
            error_kind: ErrorKind::Internal,
            message: message.into(),
            metadata: None,
        }
    }
}

#[cfg(test)]
#[path = "error_tests.rs"]
mod tests;