Initial commit.

src/setup.rs

@@ -0,0 +1,108 @@
+use clap::Parser;
+use color_eyre::{
+    Result,
+    eyre::WrapErr,
+};
+use config::Config;
+use directories::ProjectDirs;
+use std::path::PathBuf;
+use tracing::{
+    info,
+    instrument,
+};
+
+// TODO: use [clap(long, short, help_heading = Some(section))]
+#[derive(Clone, Debug, Parser)]
+#[command(about, version)]
+pub(crate) struct Args {
+    #[arg(short, long)]
+    /// API Key for the LLM in use.
+    pub(crate) api_key: Option<String>,
+
+    #[arg(short, long, default_value = "https://api.openai.com")]
+    /// Base URL for the LLM API to use.
+    pub(crate) base_url: Option<String>,
+
+    #[arg(long)]
+    /// Instructions to the model on how to behave.
+    pub(crate) intruct: Option<String>,
+
+    #[arg(long)]
+    pub(crate) model: Option<String>,
+
+    #[arg(long)]
+    /// List of IRC channels to join.
+    pub(crate) channels: Option<Vec<String>>,
+
+    #[arg(short, long)]
+    /// Custom configuration file location if need be.
+    pub(crate) config_file: Option<PathBuf>,
+
+    #[arg(short, long, default_value = "irc.libera.chat")]
+    /// IRC server.
+    pub(crate) server: Option<String>,
+
+    #[arg(short, long, default_value = "6697")]
+    /// Port of the IRC server.
+    pub(crate) port: Option<String>,
+
+    #[arg(long)]
+    /// IRC Nickname.
+    pub(crate) nickname: Option<String>,
+
+    #[arg(long)]
+    /// IRC Nick Password
+    pub(crate) nick_password: Option<String>,
+
+    #[arg(long)]
+    /// IRC Username
+    pub(crate) username: Option<String>,
+
+    #[arg(long)]
+    /// Whether or not to use TLS when connecting to the IRC server.
+    pub(crate) use_tls: Option<bool>,
+}
+
+pub(crate) struct Setup {
+    pub(crate) config: Config,
+}
+
+#[instrument]
+pub async fn init() -> Result<Setup> {
+    // Get arguments.  These overrule configuration file, and environment
+    // variables if applicable.
+    let args = Args::parse();
+
+    // Use default config location unless specified.
+    let config_location: PathBuf = if let Some(ref path) = args.config_file {
+        path.to_owned()
+    } else {
+        ProjectDirs::from("", "", env!("CARGO_PKG_NAME"))
+            .unwrap()
+            .config_dir()
+            .to_owned()
+            .join(r"config.toml")
+    };
+
+    info!("Starting.");
+
+    let settings = Config::builder()
+        .add_source(config::File::with_name(&config_location.to_string_lossy()).required(false))
+        .add_source(config::Environment::with_prefix("BOT"))
+        // Doing all of these overrides provides a unified access point for options,
+        // but a derive macro could do this a bit better if this becomes too large.
+        .set_override_option("api-key", args.api_key.clone())?
+        .set_override_option("base-url", args.base_url.clone())?
+        .set_override_option("model", args.model.clone())?
+        .set_override_option("instruct", args.model.clone())?
+        .set_override_option("channels", args.channels.clone())?
+        .set_override_option("server", args.server.clone())?
+        .set_override_option("port", args.port.clone())? // FIXME: Make this a default here not in clap.
+        .set_override_option("nickname", args.nickname.clone())?
+        .set_override_option("username", args.username.clone())?
+        .set_override_option("use_tls", args.use_tls)?
+        .build()
+        .wrap_err("Couldn't read configuration settings.")?;
+
+    Ok(Setup { config: settings })
+}