feat: rewrite the nip-4e implementation (#1)

Make NIP-4e a core feature, not an optional feature.

Note:
- The UI is broken and needs to be updated in a separate PR.

Reviewed-on: #1

crates/person/src/person.rs

@@ -0,0 +1,122 @@
+use std::cmp::Ordering;
+use std::hash::{Hash, Hasher};
+
+use gpui::SharedString;
+use nostr_sdk::prelude::*;
+use state::Announcement;
+
+/// Person
+#[derive(Debug, Clone)]
+pub struct Person {
+    /// Public Key
+    public_key: PublicKey,
+
+    /// Metadata (profile)
+    metadata: Metadata,
+
+    /// Dekey (NIP-4e) announcement
+    announcement: Option<Announcement>,
+}
+
+impl PartialEq for Person {
+    fn eq(&self, other: &Self) -> bool {
+        self.public_key == other.public_key
+    }
+}
+
+impl Eq for Person {}
+
+impl PartialOrd for Person {
+    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
+        Some(self.cmp(other))
+    }
+}
+
+impl Ord for Person {
+    fn cmp(&self, other: &Self) -> Ordering {
+        self.name().cmp(&other.name())
+    }
+}
+
+impl Hash for Person {
+    fn hash<H: Hasher>(&self, state: &mut H) {
+        self.public_key.hash(state)
+    }
+}
+
+impl From<PublicKey> for Person {
+    fn from(public_key: PublicKey) -> Self {
+        Self::new(public_key, Metadata::default())
+    }
+}
+
+impl Person {
+    pub fn new(public_key: PublicKey, metadata: Metadata) -> Self {
+        Self {
+            public_key,
+            metadata,
+            announcement: None,
+        }
+    }
+
+    /// Get profile public key
+    pub fn public_key(&self) -> PublicKey {
+        self.public_key
+    }
+
+    /// Get profile metadata
+    pub fn metadata(&self) -> Metadata {
+        self.metadata.clone()
+    }
+
+    /// Get profile encryption keys announcement
+    pub fn announcement(&self) -> Option<Announcement> {
+        self.announcement.clone()
+    }
+
+    /// Set profile encryption keys announcement
+    pub fn set_announcement(&mut self, announcement: Announcement) {
+        self.announcement = Some(announcement);
+        log::info!("Updated announcement for: {}", self.public_key());
+    }
+
+    /// Get profile avatar
+    pub fn avatar(&self) -> SharedString {
+        self.metadata()
+            .picture
+            .as_ref()
+            .filter(|picture| !picture.is_empty())
+            .map(|picture| picture.into())
+            .unwrap_or_else(|| "brand/avatar.png".into())
+    }
+
+    /// Get profile name
+    pub fn name(&self) -> SharedString {
+        if let Some(display_name) = self.metadata().display_name.as_ref() {
+            if !display_name.is_empty() {
+                return SharedString::from(display_name);
+            }
+        }
+
+        if let Some(name) = self.metadata().name.as_ref() {
+            if !name.is_empty() {
+                return SharedString::from(name);
+            }
+        }
+
+        SharedString::from(shorten_pubkey(self.public_key(), 4))
+    }
+}
+
+/// Shorten a [`PublicKey`] to a string with the first and last `len` characters
+///
+/// Ex. `00000000:00000002`
+pub fn shorten_pubkey(public_key: PublicKey, len: usize) -> String {
+    let Ok(pubkey) = public_key.to_bech32();
+
+    format!(
+        "{}:{}",
+        &pubkey[0..(len + 1)],
+        &pubkey[pubkey.len() - len..]
+    )
+}