feat(tui): search a room's log and members, and a conversation

A busy room's log scrolls past and its member list runs to a thousand
names, with nothing to narrow either. In a room / now filters the log
to lines mentioning the text and u filters the member list, the same
way the room list and the results filter: type, Enter keeps it, Esc
clears it before it leaves the room. The inbox takes / over the open
conversation. The member keys, b and m among them, act on the narrowed
list, and the titles say what is filtered and how many made it.

soulseek-rs/src/ui/main_tui/input.rs

@@ -190,6 +190,34 @@ impl MainTui {
             return;
         }
 
+        // Typing a filter captures the keys that edit it; the rest still
+        // move around.
+        if self.state.chat_filtering {
+            match key.code {
+                KeyCode::Esc => {
+                    self.state.chat_filtering = false;
+                    self.state.chat_filter.clear();
+                    self.state.chat_view.to_newest();
+                    return;
+                }
+                KeyCode::Enter => {
+                    self.state.chat_filtering = false;
+                    return;
+                }
+                KeyCode::Char(c) => {
+                    self.state.chat_filter.push(c);
+                    self.state.chat_view.to_newest();
+                    return;
+                }
+                KeyCode::Backspace => {
+                    self.state.chat_filter.pop();
+                    self.state.chat_view.to_newest();
+                    return;
+                }
+                _ => {}
+            }
+        }
+
         // Paging keys move through the conversation's history.
         if scroll_log(&mut self.state.chat_view, key) {
             return;
@@ -199,9 +227,15 @@ impl MainTui {
         }
 
         match key.code {
+            // Esc peels back one level: a filter first, then the popup.
+            KeyCode::Esc if !self.state.chat_filter.is_empty() => {
+                self.state.chat_filter.clear();
+                self.state.chat_view.to_newest();
+            }
             KeyCode::Char('i' | 'q') | KeyCode::Esc => {
                 self.state.show_messages = false;
             }
+            KeyCode::Char('/') => self.state.chat_filtering = true,
             // Move through the conversation list on the right.
             KeyCode::Tab | KeyCode::Down | KeyCode::Char('j') => {
                 self.state.cycle_chat_peer(true);

soulseek-rs/src/ui/main_tui/mod.rs

@@ -265,7 +265,9 @@ pub fn launch_main_tui(
 mod tests {
     use super::*;
     use crate::daemon::proto::ChatMessageDto;
-    use crate::models::{FocusedPane, MessageDirection, SearchStatus};
+    use crate::models::{
+        FocusedPane, MessageDirection, RoomsView, SearchStatus,
+    };
     use ratatui::crossterm::event::{KeyCode, KeyEvent, KeyModifiers};
 
     /// A stand-in for a daemon: it already holds a conversation, a transfer
@@ -1747,6 +1749,68 @@ mod tests {
         assert!(!tui.state.show_browse, "then hides the popup");
     }
 
+    #[test]
+    fn slash_and_u_filter_a_rooms_log_and_its_members() {
+        let mut tui = attach(Arc::new(TalkativeSession::default()));
+        in_a_room(&mut tui, 30);
+        press(&mut tui, KeyCode::Char('u'));
+        for c in "user2".chars() {
+            press(&mut tui, KeyCode::Char(c));
+        }
+        press(&mut tui, KeyCode::Enter);
+        press(&mut tui, KeyCode::Char('j'));
+        assert_eq!(
+            tui.state.rooms.selected_user().as_deref(),
+            Some("user21"),
+            "j moves within the matching members"
+        );
+        let screen = screen_of(&mut tui);
+        assert!(screen.contains("Users 10/30"), "{screen}");
+
+        press(&mut tui, KeyCode::Char('/'));
+        for c in "line 01".chars() {
+            press(&mut tui, KeyCode::Char(c));
+        }
+        let screen = screen_of(&mut tui);
+        assert!(screen.contains("line 010"), "{screen}");
+        assert!(!screen.contains("line 029"), "{screen}");
+        assert!(screen.contains("filter: line 01_"), "{screen}");
+        press(&mut tui, KeyCode::Enter);
+        press(&mut tui, KeyCode::Esc);
+        assert!(tui.state.rooms.log_filter.is_empty());
+        assert!(tui.state.rooms.user_filter.is_empty());
+        assert_eq!(tui.state.rooms.view, RoomsView::Chat, "still in the room");
+        press(&mut tui, KeyCode::Esc);
+        assert_eq!(tui.state.rooms.view, RoomsView::List, "then the list");
+    }
+
+    #[test]
+    fn slash_filters_the_open_conversation() {
+        let mut tui = attach(Arc::new(TalkativeSession::default()));
+        for text in ["hello there", "see you", "hello again"] {
+            tui.state.messages.push(crate::models::ChatMessage {
+                direction: MessageDirection::Incoming,
+                peer: "bob".to_string(),
+                text: text.to_string(),
+                at: chrono::Local::now(),
+            });
+        }
+        tui.state.chat_peer = Some("bob".to_string());
+        tui.state.show_messages = true;
+        press(&mut tui, KeyCode::Char('/'));
+        for c in "hello".chars() {
+            press(&mut tui, KeyCode::Char(c));
+        }
+        let screen = screen_of(&mut tui);
+        assert!(screen.contains("hello again"), "{screen}");
+        assert!(!screen.contains("see you"), "{screen}");
+        press(&mut tui, KeyCode::Enter);
+        press(&mut tui, KeyCode::Esc);
+        assert!(tui.state.chat_filter.is_empty() && tui.state.show_messages);
+        press(&mut tui, KeyCode::Esc);
+        assert!(!tui.state.show_messages);
+    }
+
     fn in_a_room(tui: &mut MainTui, messages: usize) {
         tui.state.rooms.apply_event(
             soulseek_rs::RoomEvent::Joined {

soulseek-rs/src/ui/main_tui/render.rs

@@ -96,6 +96,8 @@ const HELP_RIGHT: &[(&str, &[(&str, &str)])] = &[
             ("^u ^d", "half a page of them"),
             ("Home End / g G", "oldest / newest, or first / last row"),
             ("Tab / Shift-Tab", "next room, chat or user"),
+            ("/", "filter the messages, the room list or the tree"),
+            ("u", "filter a room's member list"),
         ],
     ),
     (
@@ -494,10 +496,21 @@ impl MainTui {
                     ]
                 }
             }
+            RoomsView::Chat if self.state.rooms.filtering.is_some() => {
+                vec![
+                    ("Type", "filter"),
+                    ("PgUp/PgDn", "scroll"),
+                    ("↑↓", "pick user"),
+                    ("Enter", "keep filter"),
+                    ("Esc", "clear filter"),
+                ]
+            }
             RoomsView::Chat => vec![
                 ("Enter", "say"),
                 ("PgUp/PgDn", "scroll"),
                 ("↑↓", "pick user"),
+                ("/", "find in chat"),
+                ("u", "find user"),
                 ("b", "browse user"),
                 ("m", "message user"),
                 ("Tab", "switch room"),
@@ -551,11 +564,19 @@ impl MainTui {
                     ("Enter", "send"),
                     ("Esc", "stop typing"),
                 ]
+            } else if self.state.chat_filtering {
+                vec![
+                    ("Type", "filter"),
+                    ("PgUp/PgDn", "scroll"),
+                    ("Enter", "keep filter"),
+                    ("Esc", "clear filter"),
+                ]
             } else {
                 vec![
                     ("Enter", "type"),
                     ("PgUp/PgDn", "scroll"),
                     ("↑↓/Tab", "switch chat"),
+                    ("/", "find"),
                     ("m", "new chat"),
                     ("i/Esc", "close"),
                 ]

soulseek-rs/src/ui/main_tui/rooms.rs

@@ -1,6 +1,6 @@
 use super::MainTui;
 use super::input::{jumped, list_jump, scroll_log};
-use crate::models::RoomsView;
+use crate::models::{ChatFilter, RoomsView};
 use ratatui::crossterm::event::{KeyCode, KeyEvent, KeyModifiers};
 
 impl MainTui {
@@ -30,6 +30,14 @@ impl MainTui {
             self.handle_room_filter_input(key);
             return;
         }
+        // So does typing a filter over the log or the member list; the
+        // other keys still move around.
+        if self.state.rooms.view == RoomsView::Chat
+            && self.state.rooms.filtering.is_some()
+            && self.handle_chat_filter_input(key)
+        {
+            return;
+        }
 
         match self.state.rooms.view {
             RoomsView::List => self.handle_rooms_list_input(key),
@@ -113,11 +121,24 @@ impl MainTui {
         if key.modifiers.contains(KeyModifiers::CONTROL) {
             return;
         }
+        let filtered = !self.state.rooms.log_filter.is_empty()
+            || !self.state.rooms.user_filter.is_empty();
         match key.code {
             KeyCode::Char('q') => self.state.show_rooms = false,
+            // Esc peels back one level: the filters first, then the list.
+            KeyCode::Esc if filtered => {
+                self.state.rooms.set_log_filter(String::new());
+                self.state.rooms.set_user_filter(String::new());
+            }
             KeyCode::Esc | KeyCode::Char('l') => {
                 self.state.rooms.view = RoomsView::List;
             }
+            KeyCode::Char('/') => {
+                self.state.rooms.filtering = Some(ChatFilter::Log);
+            }
+            KeyCode::Char('u') => {
+                self.state.rooms.filtering = Some(ChatFilter::Users);
+            }
             KeyCode::Tab => self.state.rooms.next_tab(),
             KeyCode::BackTab => self.state.rooms.prev_tab(),
             KeyCode::Char('x') => self.leave_active_room(),
@@ -137,6 +158,42 @@ impl MainTui {
         }
     }
 
+    /// The keys that edit whichever filter is being typed, the log's or the
+    /// member list's. Says whether `key` was one of them.
+    fn handle_chat_filter_input(&mut self, key: KeyEvent) -> bool {
+        let rooms = &mut self.state.rooms;
+        let over_log = rooms.filtering == Some(ChatFilter::Log);
+        let current = if over_log {
+            rooms.log_filter.clone()
+        } else {
+            rooms.user_filter.clone()
+        };
+        let next = match key.code {
+            KeyCode::Esc => String::new(),
+            KeyCode::Enter => current,
+            KeyCode::Char(c) => {
+                let mut next = current;
+                next.push(c);
+                next
+            }
+            KeyCode::Backspace => {
+                let mut next = current;
+                next.pop();
+                next
+            }
+            _ => return false,
+        };
+        if matches!(key.code, KeyCode::Esc | KeyCode::Enter) {
+            rooms.filtering = None;
+        }
+        if over_log {
+            rooms.set_log_filter(next);
+        } else {
+            rooms.set_user_filter(next);
+        }
+        true
+    }
+
     /// Browse the shares of the member highlighted in the active room. Closes
     /// the rooms popup so the browse tree is the sole overlay.
     fn browse_selected_room_user(&mut self) {