genja-core 0.1.0

//! Core error types for Genja.
//!
//! This module currently defines configuration, inventory, and runtime error types used by
//! core APIs to report failures in a consistent way.

use std::fmt;

/// Logical inventory section associated with an inventory load error.
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum InventoryFileKind {
    /// The hosts inventory file.
    Hosts,
    /// The groups inventory file.
    Groups,
    /// The defaults inventory file.
    Defaults,
}

impl fmt::Display for InventoryFileKind {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        match self {
            InventoryFileKind::Hosts => write!(f, "hosts"),
            InventoryFileKind::Groups => write!(f, "groups"),
            InventoryFileKind::Defaults => write!(f, "defaults"),
        }
    }
}

/// Error returned when inventory loading fails.
#[derive(Debug, Clone)]
pub enum InventoryLoadError {
    /// Reading an inventory file failed.
    Read {
        /// Which logical inventory file failed.
        kind: InventoryFileKind,
        /// Filesystem path that was being read.
        path: String,
        /// Underlying read failure rendered as text.
        message: String,
    },
    /// Parsing a JSON inventory file failed.
    ParseJson {
        /// Which logical inventory file failed.
        kind: InventoryFileKind,
        /// Filesystem path that was being parsed.
        path: String,
        /// Underlying parse failure rendered as text.
        message: String,
    },
    /// Parsing a YAML inventory file failed.
    ParseYaml {
        /// Which logical inventory file failed.
        kind: InventoryFileKind,
        /// Filesystem path that was being parsed.
        path: String,
        /// Underlying parse failure rendered as text.
        message: String,
    },
    /// The inventory file extension is not supported.
    UnsupportedFormat {
        /// Which logical inventory file failed.
        kind: InventoryFileKind,
        /// Filesystem path with the unsupported extension.
        path: String,
    },
    /// A configured transform plugin was not found.
    TransformPluginNotFound {
        /// Missing plugin name.
        name: String,
    },
    /// A configured plugin exists but is not a transform-function plugin.
    NotTransformPlugin {
        /// Plugin name with the wrong type.
        name: String,
    },
    /// A human-readable fallback error message.
    Message(String),
}

impl fmt::Display for InventoryLoadError {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        match self {
            InventoryLoadError::Read {
                kind,
                path,
                message,
            } => write!(f, "failed to read {kind} inventory file {path}: {message}"),
            InventoryLoadError::ParseJson {
                kind,
                path,
                message,
            } => write!(
                f,
                "failed to parse {kind} inventory JSON file {path}: {message}"
            ),
            InventoryLoadError::ParseYaml {
                kind,
                path,
                message,
            } => write!(
                f,
                "failed to parse {kind} inventory YAML file {path}: {message}"
            ),
            InventoryLoadError::UnsupportedFormat { kind, path } => write!(
                f,
                "unsupported {kind} inventory file format for {path}. Use .json, .yaml, or .yml"
            ),
            InventoryLoadError::TransformPluginNotFound { name } => {
                write!(f, "transform plugin '{name}' not found")
            }
            InventoryLoadError::NotTransformPlugin { name } => {
                write!(f, "plugin '{name}' is not a transform function plugin")
            }
            InventoryLoadError::Message(msg) => write!(f, "{msg}"),
        }
    }
}

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

impl From<String> for InventoryLoadError {
    fn from(value: String) -> Self {
        InventoryLoadError::Message(value)
    }
}

impl From<&str> for InventoryLoadError {
    fn from(value: &str) -> Self {
        InventoryLoadError::Message(value.to_string())
    }
}

/// Error returned when SSH configuration validation or parsing fails.
#[derive(Debug, Clone)]
pub enum SshConfigError {
    /// The SSH config file path does not exist.
    NotFound { path: String },
    /// The SSH config file exists but access was denied.
    PermissionDenied { path: String, message: String },
    /// Checking whether the SSH config file exists failed.
    CheckFailed { path: String, message: String },
    /// Opening the SSH config file failed.
    OpenFailed { path: String, message: String },
    /// Parsing the SSH config file failed.
    ParseFailed { path: String, message: String },
}

impl fmt::Display for SshConfigError {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        match self {
            SshConfigError::NotFound { path } => write!(f, "SSH config file not found: {path}"),
            SshConfigError::PermissionDenied { path, message } => {
                write!(
                    f,
                    "SSH config file exists but permission denied: {path}: {message}"
                )
            }
            SshConfigError::CheckFailed { path, message } => {
                write!(f, "Failed to check SSH config file {path}: {message}")
            }
            SshConfigError::OpenFailed { path, message } => {
                write!(f, "Failed to open SSH config file {path}: {message}")
            }
            SshConfigError::ParseFailed { path, message } => {
                write!(f, "Failed to parse SSH config file {path}: {message}")
            }
        }
    }
}

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

/// Error returned when loading the top-level settings file fails.
#[derive(Debug, Clone)]
pub enum ConfigLoadError {
    /// The settings file extension is not supported.
    UnsupportedFormat { path: String },
    /// Building the config source from disk failed.
    Read { path: String, message: String },
    /// Deserializing settings from the config source failed.
    Deserialize { path: String, message: String },
    /// SSH configuration referenced by settings failed validation.
    SshConfig(SshConfigError),
}

impl fmt::Display for ConfigLoadError {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        match self {
            ConfigLoadError::UnsupportedFormat { path } => {
                write!(
                    f,
                    "unsupported settings file format for {path}. Use .json, .yaml, or .yml"
                )
            }
            ConfigLoadError::Read { path, message } => {
                write!(f, "failed to read settings from {path}: {message}")
            }
            ConfigLoadError::Deserialize { path, message } => {
                write!(f, "failed to deserialize settings from {path}: {message}")
            }
            ConfigLoadError::SshConfig(err) => write!(f, "{err}"),
        }
    }
}

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

/// Generic error type for core Genja operations.
#[derive(Debug, Clone)]
pub enum GenjaError {
    /// Plugins have not been loaded for the runtime.
    PluginsNotLoaded,
    /// Inventory has not been loaded for the runtime.
    InventoryNotLoaded,
    /// A requested plugin name could not be found.
    PluginNotFound(String),
    /// The named plugin is not an inventory plugin.
    NotInventoryPlugin(String),
    /// The named plugin is an async-only inventory plugin and requires async construction.
    AsyncInventoryPluginRequiresAsyncConstruction(String),
    /// The named plugin is not a runner plugin.
    NotRunnerPlugin(String),
    /// A plugin failed to load.
    PluginLoad(String),
    /// The configuration file could not be read, parsed, or validated.
    ConfigLoad(ConfigLoadError),
    /// Inventory loading failed.
    InventoryLoad(InventoryLoadError),
    /// A human-readable error message.
    Message(String),
    /// Functionality is not implemented yet.
    NotImplemented(&'static str),
}

impl fmt::Display for GenjaError {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        match self {
            GenjaError::PluginsNotLoaded => write!(f, "plugins have not been loaded"),
            GenjaError::InventoryNotLoaded => write!(f, "inventory has not been loaded"),
            GenjaError::PluginNotFound(name) => write!(f, "plugin '{name}' not found"),
            GenjaError::NotInventoryPlugin(name) => {
                write!(f, "plugin '{name}' is not an inventory plugin")
            }
            GenjaError::AsyncInventoryPluginRequiresAsyncConstruction(name) => {
                write!(
                    f,
                    "async inventory plugin '{name}' requires async runtime construction"
                )
            }
            GenjaError::NotRunnerPlugin(name) => {
                write!(f, "plugin '{name}' is not a runner plugin")
            }
            GenjaError::PluginLoad(err) => write!(f, "failed to load plugins: {err}"),
            GenjaError::ConfigLoad(err) => write!(f, "failed to load settings: {err}"),
            GenjaError::InventoryLoad(err) => write!(f, "failed to load inventory: {err}"),
            GenjaError::Message(msg) => write!(f, "{msg}"),
            GenjaError::NotImplemented(msg) => write!(f, "{msg}"),
        }
    }
}

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

impl From<String> for GenjaError {
    fn from(value: String) -> Self {
        GenjaError::Message(value)
    }
}

impl From<&str> for GenjaError {
    fn from(value: &str) -> Self {
        GenjaError::Message(value.to_string())
    }
}

impl From<InventoryLoadError> for GenjaError {
    fn from(value: InventoryLoadError) -> Self {
        GenjaError::InventoryLoad(value)
    }
}

impl From<ConfigLoadError> for GenjaError {
    fn from(value: ConfigLoadError) -> Self {
        GenjaError::ConfigLoad(value)
    }
}