Do more on channel join (#7268)

This change makes it so that if you are the first to join a channel,
your project is automatically shared.

It also makes it so that if you join a channel via a link and there are
no shared projects, you open the notes instead of an empty workspace
with nothing.

This is to try and address the discoverability of project sharing: we've
had
two reviews that have talked about channels, but not talked about
sharing
projects into them, which makes me suspect they didn't know about the
feature.

Release Notes:

- Added a setting `share_on_join` (defaulting to true). When set, and
you join an empty channel, your project is automatically shared.

crates/workspace/src/workspace.rs

@@ -12,7 +12,7 @@ mod toolbar;
 mod workspace_settings;
 
 use anyhow::{anyhow, Context as _, Result};
-use call::ActiveCall;
+use call::{call_settings::CallSettings, ActiveCall};
 use client::{
     proto::{self, ErrorCode, PeerId},
     Client, ErrorExt, Status, TypedEnvelope, UserStore,
@@ -3974,6 +3974,8 @@ pub async fn last_opened_workspace_paths() -> Option<WorkspaceLocation> {
     DB.last_workspace().await.log_err().flatten()
 }
 
+actions!(collab, [OpenChannelNotes]);
+
 async fn join_channel_internal(
     channel_id: u64,
     app_state: &Arc<AppState>,
@@ -4075,6 +4077,36 @@ async fn join_channel_internal(
             return Some(join_remote_project(project, host, app_state.clone(), cx));
         }
 
+        // if you are the first to join a channel, share your project
+        if room.remote_participants().len() == 0 && !room.local_participant_is_guest() {
+            if let Some(workspace) = requesting_window {
+                let project = workspace.update(cx, |workspace, cx| {
+                    if !CallSettings::get_global(cx).share_on_join {
+                        return None;
+                    }
+                    let project = workspace.project.read(cx);
+                    if project.is_local()
+                        && project.visible_worktrees(cx).any(|tree| {
+                            tree.read(cx)
+                                .root_entry()
+                                .map_or(false, |entry| entry.is_dir())
+                        })
+                    {
+                        Some(workspace.project.clone())
+                    } else {
+                        None
+                    }
+                });
+                if let Ok(Some(project)) = project {
+                    return Some(cx.spawn(|room, mut cx| async move {
+                        room.update(&mut cx, |room, cx| room.share_project(project, cx))?
+                            .await?;
+                        Ok(())
+                    }));
+                }
+            }
+        }
+
         None
     })?;
     if let Some(task) = task {
@@ -4117,6 +4149,12 @@ pub fn join_channel(
                 })?
                 .await?;
 
+            if result.is_ok() {
+                cx.update(|cx| {
+                    cx.dispatch_action(&OpenChannelNotes);
+                }).log_err();
+            }
+
             active_window = Some(window_handle);
         }