chore: sync octobase's update (#25)

y-octo/Cargo.toml

@@ -27,6 +27,7 @@ nom           = "7.1"
 ordered-float = "3.8"
 rand          = "0.8"
 rand_chacha   = "0.3"
+rand_distr    = "0.4.3"
 serde         = { version = "1.0", features = ["derive"] }
 serde_json    = "1.0"
 thiserror     = "1.0"

y-octo/src/doc/codec/item.rs

@@ -221,17 +221,22 @@ impl Item {
         }
     }
 
-    pub fn resolve_parent(&self) -> Option<(Option<Parent>, Option<String>)> {
-        if let Some(item) = self.left.get() {
+    // find a note that has parent info
+    // in crdt tree, not all node has parent info
+    // so we need to check left and right node if they have parent info
+    pub fn find_node_with_parent_info(&self) -> Option<Item> {
+        if self.parent.is_some() {
+            return Some(self.clone());
+        } else if let Some(item) = self.left.get() {
             if item.parent.is_none() {
                 if let Some(item) = item.right.get() {
-                    return Some((item.parent.clone(), item.parent_sub.clone()));
+                    return Some(item.clone());
                 }
             } else {
-                return Some((item.parent.clone(), item.parent_sub.clone()));
+                return Some(item.clone());
             }
         } else if let Some(item) = self.right.get() {
-            return Some((item.parent.clone(), item.parent_sub.clone()));
+            return Some(item.clone());
         }
         None
     }

y-octo/src/doc/document.rs

@@ -1,6 +1,6 @@
 use std::collections::HashMap;
 
-use super::{publisher::DocPublisher, store::StoreRef, *};
+use super::{history::StoreHistory, publisher::DocPublisher, store::StoreRef, *};
 use crate::sync::{Arc, RwLock};
 
 #[cfg(feature = "debug")]
@@ -42,8 +42,26 @@ impl Default for DocOptions {
                 gc: true,
             }
         } else {
+            /// It tends to generate small numbers.
+            /// Since the client id will be included in all crdt items, the
+            /// small client helps to reduce the binary size.
+            ///
+            /// NOTE: The probability of 36% of the random number generated by
+            /// this function is greater than [u32::MAX]
+            fn prefer_small_random() -> u64 {
+                use rand::{distributions::Distribution, thread_rng};
+                use rand_distr::Exp;
+
+                let scale_factor = u16::MAX as f64;
+                let v: f64 = Exp::new(1.0 / scale_factor)
+                    .map(|exp| exp.sample(&mut thread_rng()))
+                    .unwrap_or_else(|_| rand::random());
+
+                (v * scale_factor) as u64
+            }
+
             Self {
-                client_id: rand::random(),
+                client_id: prefer_small_random(),
                 guid: nanoid::nanoid!(),
                 gc: true,
             }
@@ -164,8 +182,10 @@ impl Doc {
         self.store.read().unwrap().clients()
     }
 
-    pub fn history(&self, client: u64) -> Option<Vec<RawHistory>> {
-        self.store.read().unwrap().history(client)
+    pub fn history(&self) -> StoreHistory {
+        let history = StoreHistory::new(&self.store);
+        history.resolve();
+        history
     }
 
     #[cfg(feature = "debug")]
@@ -343,14 +363,18 @@ impl Doc {
         self.store.read().unwrap().get_state_vector()
     }
 
-    pub fn subscribe(&self, cb: impl Fn(&[u8]) + Sync + Send + 'static) {
+    pub fn subscribe(&self, cb: impl Fn(&[u8], &[History]) + Sync + Send + 'static) {
         self.publisher.subscribe(cb);
     }
 
     pub fn unsubscribe_all(&self) {
         self.publisher.unsubscribe_all();
     }
 
+    pub fn subscribe_count(&self) -> usize {
+        self.publisher.count()
+    }
+
     pub fn gc(&self) -> JwstCodecResult<()> {
         self.store.write().unwrap().optimize()
     }
@@ -504,11 +528,11 @@ mod tests {
             let count = Arc::new(AtomicU8::new(0));
             let count_clone1 = count.clone();
             let count_clone2 = count.clone();
-            doc.subscribe(move |_| {
+            doc.subscribe(move |_, _| {
                 count_clone1.fetch_add(1, Ordering::SeqCst);
             });
 
-            doc_clone.subscribe(move |_| {
+            doc_clone.subscribe(move |_, _| {
                 count_clone2.fetch_add(1, Ordering::SeqCst);
             });