feat: Support signing using NIP-46 bunker

Suggested-by: DanConwayDev <DanConwayDev@protonmail.com>
Signed-off-by: Awiteb <a@4rs.nl>

src/cli/mod.rs

@@ -33,11 +33,14 @@ pub mod types;
 
 use clap::Parser;
 use clap_verbosity_flag::Verbosity;
+use nostr::key::Keys;
+use nostr_keyring::NostrKeyring;
 use types::RelayOrSet;
 
 pub use self::commands::*;
 pub use self::config::*;
 use self::traits::CommandRunner;
+use crate::error::N34Error;
 use crate::error::N34Result;
 
 /// Header message, used in the help message
@@ -51,6 +54,12 @@ Git repository: https://git.4rs.nl/awiteb/n34.git"#;
 /// Footer message, used in the help message
 const FOOTER: &str = r#"Please report bugs to <naddr1qqpkuve5qgsqqqqqq9g9uljgjfcyd6dm4fegk8em2yfz0c3qp3tc6mntkrrhawgrqsqqqauesksc39>."#;
 
+/// Keyring service name of n34
+const N34_KEYRING_SERVICE_NAME: &str = "n34";
+
+/// Keyring entry name for the n34 keypair
+const N34_KEY_PAIR_ENTRY: &str = "n34_keypair";
+
 /// Name of the file storing the repository address
 pub const NOSTR_ADDRESS_FILE: &str = "nostr-address";
 
@@ -75,6 +84,22 @@ impl Cli {
     pub async fn run(self) -> N34Result<()> {
         self.command.run(self.options).await
     }
+
+    /// Gets the n34 keypair from the keyring or generates and stores a new one
+    /// if none exists.
+    pub fn n34_keypair() -> N34Result<Keys> {
+        let keyring = NostrKeyring::new(N34_KEYRING_SERVICE_NAME);
+
+        match keyring.get(N34_KEY_PAIR_ENTRY) {
+            Ok(keys) => Ok(keys),
+            Err(nostr_keyring::Error::Keyring(keyring::Error::NoEntry)) => {
+                let new_keys = Keys::generate();
+                keyring.set(N34_KEY_PAIR_ENTRY, &new_keys)?;
+                Ok(new_keys)
+            }
+            Err(err) => Err(N34Error::Keyring(err)),
+        }
+    }
 }
 
 /// Processes the CLI configuration by applying fallback values from config if
@@ -88,5 +113,11 @@ pub fn post_cli(mut cli: Cli) -> N34Result<Cli> {
         cli.options.relays = relays.iter().cloned().map(RelayOrSet::Relay).collect();
     }
 
+    if cli.options.bunker_url.is_none()
+        && let Some(bunker_url) = &cli.options.config.bunker_url
+    {
+        cli.options.bunker_url = Some(bunker_url.clone());
+    }
+
     Ok(cli)
 }