feat: Prediction

src/client.rs

@@ -54,7 +54,7 @@ impl Client {
         if user.is_none() {
             return None;
         }
-        let path = user.unwrap().path();
+        let path = user.unwrap().path;
         if path.is_none() {
             return None;
         }

src/file.rs

@@ -80,9 +80,12 @@ impl File {
         self.save();
     }
 
-    pub fn update(&mut self, add_or_delete: &String, beg: usize, end: usize, contents: &String) {
+    pub fn update(&mut self, add_or_delete: &String, beg: isize, end: isize, contents: &String) {
         let view = self.view.as_mut().unwrap();
 
+        let beg = beg as usize;
+        let end = end as usize;
+
         match add_or_delete.clone().as_str() {
             "add" => {
                 view.insert(beg, &contents);

src/handler/buffer.rs

@@ -14,30 +14,93 @@
  * limitations under the License.
  */
 pub use crate::handler::room::*;
+pub use std::net::SocketAddr;
 
 /// Addition and Deletion to the buffer.
 pub mod update {
     use crate::handler::buffer::*;
 
     const METHOD: &str = "buffer::update";
 
+    fn predict_delta(add_or_delete: &String, beg: isize, end: isize) -> isize {
+        if add_or_delete == "delete" {
+            return beg - end;
+        }
+        end - beg
+    }
+
+    fn predict_movement(
+        addr: &SocketAddr,
+        room: &mut Room,
+        add_or_delete: &String,
+        beg: isize,
+        end: isize,
+    ) {
+        let pt = beg;
+        let delta = predict_delta(&add_or_delete, beg, end);
+
+        let clients = room.get_clients_mut();
+
+        for (_addr, _client) in clients.iter_mut() {
+            // Skip for the request client.
+            if _addr == addr {
+                continue;
+            }
+
+            let user = _client.user_mut();
+
+            if user.is_none() {
+                continue;
+            }
+
+            let user = user.unwrap();
+            let point = user.point;
+
+            if point.is_none() {
+                continue;
+            }
+
+            let point = point.unwrap();
+
+            if pt <= point {
+                user.point = Some(point + delta);
+
+                if !user.region_beg.is_none() {
+                    user.region_beg = Some(user.region_beg.unwrap() + delta);
+                    user.region_end = Some(user.region_end.unwrap() + delta);
+                }
+            }
+        }
+    }
+
     pub async fn handle(channel: &mut Channel, room: &Arc<Mutex<Room>>, json: &Value) {
         let addr = &channel.get_connection().addr;
         let mut room = room.lock().await;
 
         let path = data_str(json, "path").unwrap();
         let add_or_delete = data_str(json, "add_or_delete").unwrap();
-        let beg = data_usize(json, "beg").unwrap();
-        let end = data_usize(json, "end").unwrap();
+        let beg = data_isize(json, "beg").unwrap();
+        let end = data_isize(json, "end").unwrap();
         let contents = data_str(json, "contents").unwrap();
 
+        // Update the buffer view.
+        {
+            let file = room.get_file_create_mut(&addr, &path, None);
+            let file = file.unwrap();
+
+            let rel_file = file.relative_path();
+
+            file.update(&add_or_delete, beg, end, &contents);
+        }
+
+        // Predict mouse movement.
+        predict_movement(addr, &mut room, &add_or_delete, beg, end);
+
         let file = room.get_file_create_mut(&addr, &path, None);
         let file = file.unwrap();
 
         let rel_file = file.relative_path();
 
-        file.update(&add_or_delete, beg, end, &contents);
-
         // Get the peers that are in the file.
         let peers = room.peers_by_file(&room, &rel_file);
 

src/handler/file.rs

@@ -80,11 +80,11 @@ pub mod info {
         let this_user = client.user().unwrap();
 
         // If user is not in the file, ignore it.
-        if this_user.path().is_none() {
+        if this_user.path.is_none() {
             return users;
         }
 
-        for _client in room.get_clients().iter() {
+        for _client in room.get_clients_vec().iter() {
             let user = _client.user();
 
             // User not entered yet.
@@ -100,7 +100,7 @@ pub mod info {
             }
 
             // Ignore when user not visiting any project files.
-            if user.path().is_none() {
+            if user.path.is_none() {
                 continue;
             }
 
@@ -152,7 +152,7 @@ pub mod say {
             return;
         }
 
-        let username = client.user().unwrap().username();
+        let username = client.user().unwrap().username.clone();
 
         let file = data_str(json, "file").unwrap();
         let file = no_room_path(&room, &file);

src/handler/room.rs

@@ -100,7 +100,7 @@ pub mod exit {
         }
 
         let user = client.user();
-        let username = user.unwrap().username();
+        let username = user.unwrap().username.clone();
 
         // Leave the room
         client.exit_room();
@@ -328,7 +328,7 @@ pub mod kick {
             return;
         }
 
-        let admin_name = client.user().unwrap().username();
+        let admin_name = client.user().unwrap().username.clone();
         // target user to kick out
         let target_name = data_str(json, "username").unwrap();
 
@@ -370,7 +370,7 @@ pub mod broadcast {
         let room = room.lock().await;
         let client = room.get_client(addr).unwrap();
 
-        let username = client.user().unwrap().username();
+        let username = client.user().unwrap().username.clone();
 
         if !check_entered(channel, client, METHOD).await {
             return;
@@ -407,9 +407,9 @@ pub mod update_client {
         }
 
         let path = data_str(json, "path");
-        let point = data_u64(json, "point");
-        let region_beg = data_u64(json, "region_beg");
-        let region_end = data_u64(json, "region_end");
+        let point = data_isize(json, "point");
+        let region_beg = data_isize(json, "region_beg");
+        let region_end = data_isize(json, "region_end");
         let color_cursor = data_str(json, "color_cursor");
         let color_region = data_str(json, "color_region");
 
@@ -420,29 +420,30 @@ pub mod update_client {
         let client = room.get_client(addr).unwrap();
         let rel_path = no_client_path(&client, &path);
 
-        let abs_path = to_room_path(addr, &room, path.unwrap());
-        let file = room.get_file(addr, &abs_path);
+        if !path.is_none() {
+            let abs_path = to_room_path(addr, &room, path.unwrap());
+            let file = room.get_file(addr, &abs_path);
 
-        if !file.is_none() {
-            let buffer = file.unwrap().buffer();
-            let buffer_md5 = md5::compute(buffer);
+            if !file.is_none() {
+                let buffer = file.unwrap().buffer();
+                let buffer_md5 = md5::compute(buffer);
 
-            // `md5_contents` is only optional.
-            if !md5_contents.is_none() {
-                let md5_contents = md5_contents.unwrap();
+                // `md5_contents` is only optional.
+                if !md5_contents.is_none() {
+                    let md5_contents = md5_contents.unwrap();
 
-                if format!("{:x}", buffer_md5) != md5_contents.as_str() {
-                    return;
+                    if format!("{:x}", buffer_md5) != md5_contents.as_str() {
+                        return;
+                    }
                 }
-            }
 
-            // `contents` is only optional.
-            if !contents.is_none() {
-                let contents = contents.unwrap();
+                // `contents` is only optional.
+                if !contents.is_none() {
+                    let contents = contents.unwrap();
 
-                if buffer_md5 != md5::compute(contents) {
-                    println!("ret");
-                    return;
+                    if buffer_md5 != md5::compute(contents) {
+                        return;
+                    }
                 }
             }
         }
@@ -472,7 +473,7 @@ pub mod info {
     fn get_users(room: &Room) -> Vec<User> {
         let mut users = Vec::new();
 
-        for client in room.get_clients().iter() {
+        for client in room.get_clients_vec().iter() {
             let user = client.user();
 
             // User not entered yet.
@@ -578,8 +579,8 @@ pub mod find_user {
 
         let user = client.user().unwrap();
 
-        let path = user.path().unwrap();
-        let point = user.point().unwrap();
+        let path = user.path.clone().unwrap();
+        let point = user.point.unwrap();
 
         channel
             .send_json(&serde_json::json!({

src/room.rs

@@ -297,7 +297,7 @@ impl Room {
                 continue;
             }
 
-            if _client.user().unwrap().username() == *username {
+            if _client.user().unwrap().username == *username {
                 return true;
             }
         }
@@ -337,13 +337,19 @@ impl Room {
         return (true, "");
     }
 
-    /// Return a list of client.
-    pub fn get_clients(&self) -> Vec<&Client> {
-        self.clients.values().collect::<Vec<&Client>>()
+    /// Return the clients as the HashMap.
+    pub fn get_clients(&self) -> &HashMap<SocketAddr, Client> {
+        &self.clients
+    }
+    pub fn get_clients_mut(&mut self) -> &mut HashMap<SocketAddr, Client> {
+        &mut self.clients
     }
 
-    /// Return a list of client.
-    pub fn get_clients_mut(&mut self) -> Vec<&mut Client> {
+    /// Return the clients as the Vec.
+    pub fn get_clients_vec(&self) -> Vec<&Client> {
+        self.clients.values().collect::<Vec<&Client>>()
+    }
+    pub fn get_clients_vec_mut(&mut self) -> Vec<&mut Client> {
         self.clients.values_mut().collect::<Vec<&mut Client>>()
     }
 
@@ -382,7 +388,7 @@ impl Room {
     /// * `username` - The client username.
     pub fn get_client_by_name(&self, username: &str) -> Option<&Client> {
         for (_addr, client) in self.clients.iter() {
-            if client.user().unwrap().username() == username {
+            if client.user().unwrap().username == username {
                 return Some(client);
             }
         }
@@ -396,7 +402,7 @@ impl Room {
     /// * `username` - The client username.
     pub fn get_client_mut_by_name(&mut self, username: &str) -> Option<&mut Client> {
         for (_addr, client) in self.clients.iter_mut() {
-            if client.user().unwrap().username() == username {
+            if client.user().unwrap().username == username {
                 return Some(client);
             }
         }

src/user.rs

@@ -17,14 +17,14 @@ use serde::{Deserialize, Serialize};
 
 #[derive(Serialize, Deserialize, Clone, PartialEq)]
 pub struct User {
-    username: String,
-    path: Option<String>, // the user's location
-    point: Option<u64>,
-    region_beg: Option<u64>,
-    region_end: Option<u64>,
+    pub username: String,
+    pub path: Option<String>, // the user's location
+    pub point: Option<isize>,
+    pub region_beg: Option<isize>,
+    pub region_end: Option<isize>,
     // Color definition
-    color_cursor: Option<String>, // hex
-    color_region: Option<String>, // hex
+    pub color_cursor: Option<String>, // hex
+    pub color_region: Option<String>, // hex
 }
 
 impl User {
@@ -40,40 +40,12 @@ impl User {
         }
     }
 
-    pub fn username(&self) -> String {
-        self.username.clone()
-    }
-
-    pub fn path(&self) -> Option<String> {
-        self.path.clone()
-    }
-
-    pub fn point(&self) -> Option<u64> {
-        self.point
-    }
-
-    pub fn region_beg(&self) -> Option<u64> {
-        self.region_beg
-    }
-
-    pub fn region_end(&self) -> Option<u64> {
-        self.region_end
-    }
-
-    pub fn color_cursor(&self) -> Option<String> {
-        self.color_cursor.clone()
-    }
-
-    pub fn color_region(&self) -> Option<String> {
-        self.color_region.clone()
-    }
-
     pub fn update(
         &mut self,
         path: Option<String>,
-        point: Option<u64>,
-        region_beg: Option<u64>,
-        region_end: Option<u64>,
+        point: Option<isize>,
+        region_beg: Option<isize>,
+        region_end: Option<isize>,
         color_cursor: Option<String>,
         color_region: Option<String>,
     ) {

src/util.rs

@@ -60,6 +60,19 @@ pub fn data_usize(json: &Value, key: &str) -> Option<usize> {
     Some(json[key].to_string().parse::<usize>().unwrap())
 }
 
+/// Get data as isize.
+///
+/// # Arguments
+///
+/// * `json` - JSON object.
+/// * `key` - Key to the data.
+pub fn data_isize(json: &Value, key: &str) -> Option<isize> {
+    if json[key].is_null() {
+        return None;
+    }
+    Some(json[key].to_string().parse::<isize>().unwrap())
+}
+
 /// Parse data to u64.
 ///
 /// # Arguments