nip4e: catch up psstpsst (#70)

Reviewed-on: #70

crates/state/src/credentials.rs

@@ -5,8 +5,8 @@ use gpui::{App, AppContext as _, Task};
 
 use crate::USER_KEYRING;
 
-/// The storage key for the NIP-4e app keys
-const APP_KEYS_KEY: &str = "coop/nip4e/app-keys";
+/// The storage key for the log of handled NIP-4e key-sync request ids
+const PROCESSED_REQUESTS_KEY: &str = "coop/nip4e/processed-requests";
 
 /// Read the stored credential as `(username, secret)`
 #[allow(clippy::type_complexity)]
@@ -94,12 +94,12 @@ fn write_named(cx: &App, key: &str, secret: &[u8]) -> Task<Result<()>> {
     }
 }
 
-/// Load the NIP-4e app keys from storage, as raw secret bytes
-pub fn read_app_keys(cx: &App) -> Task<Result<Option<Vec<u8>>>> {
-    read_named(cx, APP_KEYS_KEY)
+/// Read the log of handled key-sync request ids, as concatenated hex ids
+pub fn read_processed_requests(cx: &App) -> Task<Result<Option<Vec<u8>>>> {
+    read_named(cx, PROCESSED_REQUESTS_KEY)
 }
 
-/// Persist the NIP-4e app keys, as raw secret bytes
-pub fn write_app_keys(cx: &App, secret: &[u8]) -> Task<Result<()>> {
-    write_named(cx, APP_KEYS_KEY, secret)
+/// Persist the log of handled key-sync request ids, as concatenated hex ids
+pub fn write_processed_requests(cx: &App, ids: &[u8]) -> Task<Result<()>> {
+    write_named(cx, PROCESSED_REQUESTS_KEY, ids)
 }

crates/state/src/nip4e.rs

@@ -5,6 +5,10 @@ use nostr_sdk::prelude::*;
 pub struct Announcement {
     /// The public key of the device that created this announcement.
     public_key: PublicKey,
+    /// The id of the announcement event, for ordering
+    event_id: EventId,
+    /// The creation time of the announcement event
+    created_at: Timestamp,
 }
 
 impl Announcement {
@@ -16,11 +20,20 @@ impl Announcement {
             .and_then(|tag| tag.content())
             .and_then(|c| PublicKey::parse(c).ok())?;
 
-        Some(Self { public_key })
+        Some(Self {
+            public_key,
+            event_id: event.id,
+            created_at: event.created_at,
+        })
     }
 
     /// Returns the public key of the device that created this announcement.
     pub fn public_key(&self) -> PublicKey {
         self.public_key
     }
+
+    pub fn is_newer_than(&self, other: &Self) -> bool {
+        self.created_at > other.created_at
+            || (self.created_at == other.created_at && self.event_id < other.event_id)
+    }
 }