print message when no client is focused

address issue #15

src/kamp.rs

@@ -77,7 +77,19 @@ impl Dispatcher for SubCommand {
     fn dispatch<W: Write>(self, ctx: Context, mut writer: W) -> Result<()> {
         match self {
             SubCommand::Attach(opt) => cmd::attach(ctx, opt.buffer),
-            SubCommand::Edit(opt) => cmd::edit(ctx, opt.focus, opt.files),
+            SubCommand::Edit(opt) => {
+                let session = ctx.session();
+                let client = ctx.client();
+                let scratch = cmd::edit(ctx, opt.focus, opt.files)?;
+                if let (Some(client), false) = (client, opt.focus) {
+                    writeln!(
+                        writer,
+                        "{} is opened in client: {client}, session: {session}",
+                        if scratch { "scratch" } else { "file" }
+                    )?;
+                }
+                Ok(())
+            }
             SubCommand::Send(opt) => {
                 if opt.command.is_empty() {
                     return Err(Error::CommandRequired);

src/kamp/cmd/edit.rs

@@ -3,7 +3,7 @@ use std::path::PathBuf;
 
 use super::{Context, Error, Result};
 
-pub(crate) fn edit(ctx: Context, focus: bool, files: Vec<String>) -> Result<()> {
+pub(crate) fn edit(ctx: Context, focus: bool, files: Vec<String>) -> Result<bool> {
     let mut buf = String::new();
     let mut pair = [None; 2];
     let mut coord = None;
@@ -47,19 +47,21 @@ pub(crate) fn edit(ctx: Context, focus: bool, files: Vec<String>) -> Result<()>
         }
     }
 
-    if buf.is_empty() {
+    let is_scratch = buf.is_empty();
+    if is_scratch {
         buf.push_str("edit -scratch");
     }
 
     if !ctx.is_draft() {
         if focus {
             buf.push_str("\nfocus");
         }
-        ctx.send(None, &buf).map(drop)
+        ctx.send(None, &buf).map(|_| is_scratch)
     } else if focus {
         Err(anyhow::Error::msg("no client in context").into())
     } else {
-        ctx.connect(&buf) // this one acts like attach
+        // this one acts like attach
+        ctx.connect(&buf).map(|_| is_scratch)
     }
 }