restore broot on return from an application launched in terminal

This might
fix #38
fix #144
fix #158
but more tests would be needed and some applications might have
problems.
I mostly tested by launching vi from broot with
`leave_broot = false`: vi runs correctly and broot is OK when
I quit broot.

11 files changed, 57 insertions, 13 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index b12e2b2..bc2c75c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,4 +1,8 @@
 ### next version
+#### Major feature: keep broot open behind terminal editors
+If you now open vi or emacs from broot with `leave_broot = false` you should
+be back in broot after you quit the editor. Fix
+#### Minor changes:
 - it's possible to define input edition shortcuts - Fix #235
 - MacOS: config directory for new install is ~/.config/broot - Fix #103
 
diff --git a/src/app/app.rs b/src/app/app.rs
index ada3664..f9efa32 100644
--- a/src/app/app.rs
+++ b/src/app/app.rs
@@ -122,6 +122,7 @@ impl App {
     ///  or a new one.
     fn apply_command(
         &mut self,
+        w: &mut W,
         cmd: Command,
         screen: &mut Screen,
         panel_skin: &PanelSkin,
@@ -132,6 +133,7 @@ impl App {
         let is_input_invocation = cmd.is_verb_invocated_from_input();
         let other_path = self.get_other_panel_path();
         match self.mut_panel().apply_command(
+            w,
             &cmd,
             &other_path,
             screen,
@@ -153,7 +155,7 @@ impl App {
                         self.mut_panel().set_input_arg(new_arg);
                         let new_input = self.panel().get_input_content();
                         let cmd = Command::from_raw(new_input, false);
-                        self.mut_panel().apply_command(&cmd, &other_path, screen, panel_skin, con)?;
+                        self.mut_panel().apply_command(w, &cmd, &other_path, screen, panel_skin, con)?;
                     }
                 } else {
                     self.quitting = true;
@@ -215,7 +217,7 @@ impl App {
                     self.mut_panel().clear_input();
                 }
                 if self.remove_state(screen) {
-                    self.mut_panel().apply_command(&cmd, &other_path, screen, panel_skin, con)?;
+                    self.mut_panel().apply_command(w, &cmd, &other_path, screen, panel_skin, con)?;
                 } else if ESCAPE_TO_QUIT {
                     self.quitting = true;
                 }
@@ -306,7 +308,7 @@ impl App {
         if let Some(unparsed_commands) = &con.launch_args.commands {
             for (input, arg_cmd) in parse_command_sequence(unparsed_commands, con)? {
                 self.mut_panel().set_input_content(input);
-                self.apply_command(arg_cmd, screen, &skin.focused, con)?;
+                self.apply_command(w, arg_cmd, screen, &skin.focused, con)?;
                 self.display_panels(w, screen, &skin, con)?;
                 w.flush()?;
                 self.do_pending_tasks(screen, con, &mut dam)?;
@@ -356,7 +358,7 @@ impl App {
                     // event handled by the panel
                     let cmd = self.mut_panel().add_event(w, event, con)?;
                     debug!("command after add_event: {:?}", &cmd);
-                    self.apply_command(cmd, screen, &skin.focused, con)?;
+                    self.apply_command(w, cmd, screen, &skin.focused, con)?;
                 }
             }
             self.display_panels(w, screen, &skin, con)?;
diff --git a/src/app/panel.rs b/src/app/panel.rs
index 52a756a..397908e 100644
--- a/src/app/panel.rs
+++ b/src/app/panel.rs
@@ -49,6 +49,7 @@ impl Panel {
 
     pub fn apply_command(
         &mut self,
+        w: &mut W,
         cmd: &Command,
         other_path: &Option<PathBuf>,
         screen: &mut Screen,
@@ -64,7 +65,7 @@ impl Panel {
             areas: &self.areas,
             panel_purpose: self.purpose,
         };
-        let result = self.states[state_idx].on_command(&cc, screen);
+        let result = self.states[state_idx].on_command(w, &cc, screen);
         self.status = Some(self.state().get_status(cmd, other_path, con));
         debug!("result in panel {:?}: {:?}", &self.id, &result);
         result
diff --git a/src/app/state.rs b/src/app/state.rs
index b3e8300..a60ce5e 100644
--- a/src/app/state.rs
+++ b/src/app/state.rs
@@ -56,6 +56,7 @@ pub trait AppState {
     /// by a key shorctut)
     fn on_internal(
         &mut self,
+        w: &mut W,
         internal_exec: &InternalExecution,
         input_invocation: Option<&VerbInvocation>,
         trigger_type: TriggerType,
@@ -66,6 +67,7 @@ pub trait AppState {
     /// change the state, does no rendering
     fn on_command(
         &mut self,
+        w: &mut W,
         cc: &CmdContext,
         screen: &mut Screen,
     ) -> Result<AppStateCmdResult, ProgramError> {
@@ -87,6 +89,7 @@ pub trait AppState {
                 let verb = &con.verb_store.verbs[*index];
                 match &verb.execution {
                     VerbExecution::Internal(internal_exec) => self.on_internal(
+                        w,
                         internal_exec,
                         input_invocation.as_ref(),
                         TriggerType::Other,
@@ -94,6 +97,7 @@ pub trait AppState {
                         screen,
                     ),
                     VerbExecution::External(external) => external.to_cmd_result(
+                        w,
                         self.selected_path(),
                         &cc.other_path,
                         if let Some(inv) = &input_invocation {
@@ -109,6 +113,7 @@ pub trait AppState {
                 internal,
                 input_invocation,
             } => self.on_internal(
+                w,
                 &InternalExecution::from_internal(*internal),
                 input_invocation.as_ref(),
                 TriggerType::Other,
@@ -122,6 +127,7 @@ pub trait AppState {
                     } else {
                         match &verb.execution {
                             VerbExecution::Internal(internal_exec) => self.on_internal(
+                                w,
                                 internal_exec,
                                 Some(invocation),
                                 TriggerType::Input,
@@ -130,6 +136,7 @@ pub trait AppState {
                             ),
                             VerbExecution::External(external) => {
                                 external.to_cmd_result(
+                                    w,
                                     self.selected_path(),
                                     &cc.other_path,
                                     &invocation.args,
diff --git a/src/browser/browser_state.rs b/src/browser/browser_state.rs
index 9fedacd..d46b8e9 100644
--- a/src/browser/browser_state.rs
+++ b/src/browser/browser_state.rs
@@ -156,6 +156,7 @@ impl BrowserState {
 
     pub fn open_selection_quit_broot(
         &mut self,
+        w: &mut W,
         con: &AppContext,
     ) -> Result<AppStateCmdResult, ProgramError> {
         let tree = self.displayed_tree();
@@ -164,7 +165,7 @@ impl BrowserState {
             TreeLineType::File => make_opener(line.path.clone(), line.is_exe(), con),
             TreeLineType::Dir | TreeLineType::SymLinkToDir(_) => {
                 Ok(if con.launch_args.cmd_export_path.is_some() {
-                    CD.to_cmd_result(&line.target(), &None, &None, con)?
+                    CD.to_cmd_result(w, &line.target(), &None, &None, con)?
                 } else {
                     AppStateCmdResult::DisplayError(
                         "This feature needs broot to be launched with the `br` script".to_owned(),
@@ -368,6 +369,7 @@ impl AppState for BrowserState {
 
     fn on_internal(
         &mut self,
+        w: &mut W,
         internal_exec: &InternalExecution,
         input_invocation: Option<&VerbInvocation>,
         trigger_type: TriggerType,
@@ -429,7 +431,7 @@ impl AppState for BrowserState {
             }
             Internal::open_stay => self.open_selection_stay_in_broot(screen, con, bang, false)?,
             Internal::open_stay_filter => self.open_selection_stay_in_broot(screen, con, bang, true)?,
-            Internal::open_leave => self.open_selection_quit_broot(con)?,
+            Internal::open_leave => self.open_selection_quit_broot(w, con)?,
             Internal::line_down => {
                 self.displayed_tree_mut().move_selection(1, page_height);
                 AppStateCmdResult::Keep
diff --git a/src/conf/default_conf.rs b/src/conf/default_conf.rs
index a9c5083..27cc312 100644
--- a/src/conf/default_conf.rs
+++ b/src/conf/default_conf.rs
@@ -75,10 +75,12 @@ invocation = "edit"
 key = "F2"
 shortcut = "e"
 execution = "$EDITOR {file}"
+leave_broot = false
 
 [[verbs]]
 invocation = "create {subpath}"
 execution = "$EDITOR {directory}/{subpath}"
+leave_broot = false
 
 [[verbs]]
 invocation = "git_diff"
@@ -95,6 +97,7 @@ execution = "git diff {file}"
 name = "view"
 invocation = "view"
 execution = "$PAGER {file}"
+leave_broot = false
 
 # A popular set of shorctuts for going up and down:
 #
diff --git a/src/help/help_state.rs b/src/help/help_state.rs
index 59408df..9966472 100644
--- a/src/help/help_state.rs
+++ b/src/help/help_state.rs
@@ -130,6 +130,7 @@ impl AppState for HelpState {
 
     fn on_internal(
         &mut self,
+        _w: &mut W,
         internal_exec: &InternalExecution,
         input_invocation: Option<&VerbInvocation>,
         _trigger_type: TriggerType,
diff --git a/src/launchable.rs b/src/launchable.rs
index 80031ef..6c99796 100644
--- a/src/launchable.rs
+++ b/src/launchable.rs
@@ -1,12 +1,21 @@
 use {
     crate::{
-        display::{DisplayableTree, Screen},
+        display::{DisplayableTree, Screen, W},
         errors::ProgramError,
         skin::StyleMap,
         tree::Tree,
     },
+    crossterm::{
+        terminal::{EnterAlternateScreen, LeaveAlternateScreen},
+        QueueableCommand,
+    },
     open,
-    std::{env, io, path::PathBuf, process::Command},
+    std::{
+        env,
+        io::{self, Write},
+        path::PathBuf,
+        process::Command,
+    },
 };
 
 /// description of a possible launch of an external program
@@ -80,7 +89,7 @@ impl Launchable {
         }
     }
 
-    pub fn execute(&self) -> Result<(), ProgramError> {
+    pub fn execute(&self, mut w: Option<&mut W>) -> Result<(), ProgramError> {
         match self {
             Launchable::Printer { to_print } => {
                 println!("{}", to_print);
@@ -91,6 +100,13 @@ impl Launchable {
                 dp.write_on(&mut std::io::stdout())
             }
             Launchable::Program { exe, args } => {
+                // we restore the normal terminal in case the executable
+                // is a terminal application, and we'll switch back to
+                // broot's alternate terminal when we're back to broot
+                if let Some(ref mut w) = &mut w {
+                    w.queue(LeaveAlternateScreen).unwrap();
+                    w.flush().unwrap();
+                }
                 Command::new(&exe)
                     .args(args.iter())
                     .spawn()
@@ -99,6 +115,10 @@ impl Launchable {
                         program: exe.clone(),
                         source,
                     })?;
+                if let Some(ref mut w) = &mut w {
+                    w.queue(EnterAlternateScreen).unwrap();
+                    w.flush().unwrap();
+                }
                 Ok(())
             }
             Launchable::SystemOpen { path } => {
diff --git a/src/main.rs b/src/main.rs
index c137e46..2fb741d 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -44,7 +44,7 @@ fn main() {
     configure_log();
     match cli::run() {
         Ok(Some(launchable)) => {
-            if let Err(e) = launchable.execute() {
+            if let Err(e) = launchable.execute(None) {
                 warn!("Failed to launch {:?}", &launchable);
                 warn!("Error: {:?}", e);
                 eprintln!("{}", e);
diff --git a/src/verb/external_execution.rs b/src/verb/external_execution.rs
index b37e4b2..2e5cce4 100644
--- a/src/verb/external_execution.rs
+++ b/src/verb/external_execution.rs
@@ -10,6 +10,7 @@ use {
     super::{ExternalExecutionMode, VerbInvocation},
     crate::{
         app::*,
+        display::W,
         errors::{ConfError, ProgramError},
         launchable::Launchable,
         path,
@@ -204,6 +205,7 @@ impl ExternalExecution {
 
     pub fn to_cmd_result(
         &self,
+        w: &mut W,
         file: &Path,
         other_file: &Option<PathBuf>,
         args: &Option<String>,
@@ -212,7 +214,7 @@ impl ExternalExecution {
         if self.exec_mode.is_from_shell() {
             self.exec_from_shell_cmd_result(file, other_file, args, con)
         } else {
-            self.exec_cmd_result(file, other_file, args)
+            self.exec_cmd_result(w, file, other_file, args)
         }
     }
 
@@ -248,6 +250,7 @@ impl ExternalExecution {
     /// launched by broot
     fn exec_cmd_result(
         &self,
+        w: &mut W,
         file: &Path,
         other_file: &Option<PathBuf>,
         args: &Option<String>,
@@ -257,7 +260,7 @@ impl ExternalExecution {
             Ok(AppStateCmdResult::from(launchable))
         } else {
             info!("Executing not leaving, launchable {:?}", launchable);
-            let execution = launchable.execute();
+            let execution = launchable.execute(Some(w));
             match execution {
                 Ok(()) => {
                     debug!("ok");
diff --git a/website/docs/tricks.md b/website/docs/tricks.md
index db28b23..3fe923f 100644
--- a/website/docs/tricks.md
+++ b/website/docs/tricks.md
@@ -49,6 +49,7 @@ Here's an example of configuration changing the behaviour on open:
 invocation = "edit"
 key = "enter"
 execution = "$EDITOR {file}"
+leave_broot = false
 apply_to = "file"
 ```