1 files changed, 143 insertions, 0 deletions
diff --git a/src/config.rs b/src/config.rs
new file mode 100644
index 0000000..2f3e5ed
--- /dev/null
+++ b/src/config.rs
@@ -0,0 +1,143 @@
+use std::{
+    env, fs,
+    path::{Path, PathBuf},
+};
+
+use anyhow::{bail, Context, Result};
+use clap::Parser;
+use const_format::{formatcp, map_ascii_case, Case};
+use serde::Deserialize;
+
+use crate::{
+    actions::AnyActionConfig, blockchain::ElectrumConfig, message::MessageConfig,
+    wallets::WalletConfig,
+};
+
+#[derive(Parser, Debug)]
+#[command(version, about)]
+pub struct Args {
+    /// Path to toml configuration file
+    config: Option<String>,
+    /// Perform configured actions on a test notification
+    #[arg(short, long)]
+    test: bool,
+    /// Notify for every past transaction (careful: if you have a long transaction history, this
+    /// can SPAM your configured actions
+    #[arg(short, long)]
+    notify_past_txs: bool,
+}
+
+impl Args {
+    pub fn config(&self) -> Option<&str> {
+        self.config.as_deref()
+    }
+
+    pub fn test(&self) -> bool {
+        self.test
+    }
+
+    pub fn notify_past_txs(&self) -> bool {
+        self.notify_past_txs
+    }
+}
+
+fn get_config_filename() -> &'static str {
+    formatcp!("{}.toml", env!("CARGO_PKG_NAME"))
+}
+
+fn get_config_env_var() -> &'static str {
+    formatcp!(
+        "{}_CONFIG",
+        map_ascii_case!(Case::Upper, env!("CARGO_PKG_NAME"))
+    )
+}
+
+fn get_cwd_config_path() -> PathBuf {
+    PathBuf::from(".").join(get_config_filename())
+}
+
+fn get_config_path_impl(user_config_dir: &Path) -> PathBuf {
+    user_config_dir
+        .join(env!("CARGO_PKG_NAME"))
+        .join(get_config_filename())
+}
+
+fn get_user_config_path() -> Option<PathBuf> {
+    dirs::config_dir().map(|p| get_config_path_impl(&p))
+}
+
+fn get_system_config_path() -> PathBuf {
+    get_config_path_impl(&systemd_directories::config_dir().unwrap_or(PathBuf::from("/etc")))
+}
+
+fn get_config_path(maybe_arg_config: &Option<&str>) -> Result<PathBuf> {
+    if let Some(arg_path) = maybe_arg_config {
+        return Ok(PathBuf::from(arg_path));
+    }
+
+    if let Ok(env_path) = env::var(get_config_env_var()) {
+        return Ok(PathBuf::from(env_path));
+    }
+
+    let cwd_config_path = get_cwd_config_path();
+    if cwd_config_path.try_exists().is_ok_and(|x| x) {
+        return Ok(cwd_config_path);
+    }
+
+    if let Some(user_config_path) = get_user_config_path() {
+        if user_config_path.try_exists().is_ok_and(|x| x) {
+            return Ok(user_config_path);
+        }
+    }
+
+    let system_config_path = get_system_config_path();
+    if system_config_path.try_exists().is_ok_and(|x| x) {
+        return Ok(system_config_path);
+    }
+
+    bail!(
+        "no configuration file was passed as first argument, nor by the '{}' environment variable, nor did one exist in the default search paths: '{}', '{}', '{}'",
+        get_config_env_var(),
+        get_cwd_config_path().display(),
+        get_user_config_path().unwrap_or_default().display(),
+        get_system_config_path().display()
+    );
+}
+
+#[derive(Deserialize, Debug)]
+pub struct Config {
+    wallets: Vec<WalletConfig>,
+    #[serde(default)]
+    electrum: ElectrumConfig,
+    #[serde(default)]
+    message: MessageConfig,
+    #[serde(default)]
+    actions: Vec<AnyActionConfig>,
+}
+
+impl Config {
+    pub fn electrum(&self) -> &ElectrumConfig {
+        &self.electrum
+    }
+
+    pub fn wallets(&self) -> &[WalletConfig] {
+        &self.wallets
+    }
+
+    pub fn message(&self) -> &MessageConfig {
+        &self.message
+    }
+
+    pub fn actions(&self) -> &[AnyActionConfig] {
+        &self.actions
+    }
+}
+
+pub fn get_config(maybe_arg_config: &Option<&str>) -> Result<Config> {
+    let config_path = get_config_path(maybe_arg_config)?;
+    info!("reading configuration from '{}'", config_path.display());
+    let config_content = fs::read_to_string(&config_path)
+        .with_context(|| format!("could not read config file '{}'", config_path.display()))?;
+    toml::from_str(&config_content)
+        .with_context(|| format!("could not parse config file '{}'", config_path.display(),))
+}