//! Typed error enum for PoM, replacing `Box<dyn Error>` throughout the crate.

use thiserror::Error;

#[derive(Debug, Error)]
pub enum PomError {
    /// Filesystem errors (reading config, writing instance ID, etc.).
    #[error(transparent)]
    Io(#[from] std::io::Error),

    /// SQLite query or connection errors.
    #[error(transparent)]
    Db(#[from] sqlx::Error),

    /// Config file syntax errors (malformed TOML).
    #[error(transparent)]
    TomlParse(#[from] toml::de::Error),

    /// Outbound HTTP request failures (health checks, peer heartbeats).
    #[error(transparent)]
    Http(#[from] reqwest::Error),

    /// JSON serialization or deserialization errors.
    #[error(transparent)]
    Json(#[from] serde_json::Error),

    /// Invalid tracing filter directives (e.g. bad `RUST_LOG` value).
    #[error(transparent)]
    LogFilter(#[from] tracing_subscriber::filter::ParseError),

    /// Background task panicked or was cancelled.
    #[error(transparent)]
    Join(#[from] tokio::task::JoinError),

    /// Application-level config validation errors (missing config file, unknown
    /// target name, invalid instance). Distinct from `TomlParse` which covers
    /// syntax-level TOML parse failures.
    #[error("{0}")]
    Config(String),
}

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