feat(sessions): welcome screen (#3112)

* prototype - can send layout name for new session from session-manager

* feat(sessions): ui for selecting layout for new session in the session-manager

* fix: send available layouts to plugins

* make tests compile

* fix tests

* improve ui

* fix: respect built-in layouts

* ui for built-in layouts

* some cleanups

* style(fmt): rustfmt

* welcome screen ui

* fix: make sure layout config is not shared between sessions

* allow disconnecting other users from current session and killing other sessions

* fix: respect default layout

* add welcome screen layout

* tests(plugins): new api methods

* fix(session-manager): do not quit welcome screen on esc and break

* fix(plugins): adjust permissions

* style(fmt): rustfmt

* style(fmt): fix warnings

5 files changed, 328 insertions, 3 deletions

diff --git a/zellij-server/src/plugins/unit/plugin_tests.rs b/zellij-server/src/plugins/unit/plugin_tests.rs
index 6791213c..6b6e345e 100644
--- a/zellij-server/src/plugins/unit/plugin_tests.rs
+++ b/zellij-server/src/plugins/unit/plugin_tests.rs
@@ -5970,3 +5970,243 @@ pub fn pipe_message_to_plugin_plugin_command() {
         });
     assert_snapshot!(format!("{:#?}", plugin_bytes_event));
 }
+
+#[test]
+#[ignore]
+pub fn switch_session_plugin_command() {
+    let temp_folder = tempdir().unwrap(); // placed explicitly in the test scope because its
+                                          // destructor removes the directory
+    let plugin_host_folder = PathBuf::from(temp_folder.path());
+    let cache_path = plugin_host_folder.join("permissions_test.kdl");
+    let (plugin_thread_sender, server_receiver, screen_receiver, teardown) =
+        create_plugin_thread_with_server_receiver(Some(plugin_host_folder));
+    let plugin_should_float = Some(false);
+    let plugin_title = Some("test_plugin".to_owned());
+    let run_plugin = RunPlugin {
+        _allow_exec_host_cmd: false,
+        location: RunPluginLocation::File(PathBuf::from(&*PLUGIN_FIXTURE)),
+        configuration: Default::default(),
+    };
+    let tab_index = 1;
+    let client_id = 1;
+    let size = Size {
+        cols: 121,
+        rows: 20,
+    };
+    let received_screen_instructions = Arc::new(Mutex::new(vec![]));
+    let _screen_thread = grant_permissions_and_log_actions_in_thread_naked_variant!(
+        received_screen_instructions,
+        ScreenInstruction::Exit,
+        screen_receiver,
+        1,
+        &PermissionType::ChangeApplicationState,
+        cache_path,
+        plugin_thread_sender,
+        client_id
+    );
+    let received_server_instruction = Arc::new(Mutex::new(vec![]));
+    let server_thread = log_actions_in_thread!(
+        received_server_instruction,
+        ServerInstruction::SwitchSession,
+        server_receiver,
+        1
+    );
+
+    let _ = plugin_thread_sender.send(PluginInstruction::AddClient(client_id));
+    let _ = plugin_thread_sender.send(PluginInstruction::Load(
+        plugin_should_float,
+        false,
+        plugin_title,
+        run_plugin,
+        tab_index,
+        None,
+        client_id,
+        size,
+        None,
+        false,
+    ));
+    std::thread::sleep(std::time::Duration::from_millis(500));
+
+    let _ = plugin_thread_sender.send(PluginInstruction::Update(vec![(
+        None,
+        Some(client_id),
+        Event::Key(Key::Ctrl('5')), // this triggers the enent in the fixture plugin
+    )]));
+    std::thread::sleep(std::time::Duration::from_millis(500));
+    teardown();
+    server_thread.join().unwrap(); // this might take a while if the cache is cold
+    let switch_session_event = received_server_instruction
+        .lock()
+        .unwrap()
+        .iter()
+        .rev()
+        .find_map(|i| {
+            if let ServerInstruction::SwitchSession(..) = i {
+                Some(i.clone())
+            } else {
+                None
+            }
+        })
+        .clone();
+    assert_snapshot!(format!("{:#?}", switch_session_event));
+}
+
+#[test]
+#[ignore]
+pub fn switch_session_with_layout_plugin_command() {
+    let temp_folder = tempdir().unwrap(); // placed explicitly in the test scope because its
+                                          // destructor removes the directory
+    let plugin_host_folder = PathBuf::from(temp_folder.path());
+    let cache_path = plugin_host_folder.join("permissions_test.kdl");
+    let (plugin_thread_sender, server_receiver, screen_receiver, teardown) =
+        create_plugin_thread_with_server_receiver(Some(plugin_host_folder));
+    let plugin_should_float = Some(false);
+    let plugin_title = Some("test_plugin".to_owned());
+    let run_plugin = RunPlugin {
+        _allow_exec_host_cmd: false,
+        location: RunPluginLocation::File(PathBuf::from(&*PLUGIN_FIXTURE)),
+        configuration: Default::default(),
+    };
+    let tab_index = 1;
+    let client_id = 1;
+    let size = Size {
+        cols: 121,
+        rows: 20,
+    };
+    let received_screen_instructions = Arc::new(Mutex::new(vec![]));
+    let _screen_thread = grant_permissions_and_log_actions_in_thread_naked_variant!(
+        received_screen_instructions,
+        ScreenInstruction::Exit,
+        screen_receiver,
+        1,
+        &PermissionType::ChangeApplicationState,
+        cache_path,
+        plugin_thread_sender,
+        client_id
+    );
+    let received_server_instruction = Arc::new(Mutex::new(vec![]));
+    let server_thread = log_actions_in_thread!(
+        received_server_instruction,
+        ServerInstruction::SwitchSession,
+        server_receiver,
+        1
+    );
+
+    let _ = plugin_thread_sender.send(PluginInstruction::AddClient(client_id));
+    let _ = plugin_thread_sender.send(PluginInstruction::Load(
+        plugin_should_float,
+        false,
+        plugin_title,
+        run_plugin,
+        tab_index,
+        None,
+        client_id,
+        size,
+        None,
+        false,
+    ));
+    std::thread::sleep(std::time::Duration::from_millis(500));
+
+    let _ = plugin_thread_sender.send(PluginInstruction::Update(vec![(
+        None,
+        Some(client_id),
+        Event::Key(Key::Ctrl('7')), // this triggers the enent in the fixture plugin
+    )]));
+    std::thread::sleep(std::time::Duration::from_millis(500));
+    teardown();
+    server_thread.join().unwrap(); // this might take a while if the cache is cold
+    let switch_session_event = received_server_instruction
+        .lock()
+        .unwrap()
+        .iter()
+        .rev()
+        .find_map(|i| {
+            if let ServerInstruction::SwitchSession(..) = i {
+                Some(i.clone())
+            } else {
+                None
+            }
+        })
+        .clone();
+    assert_snapshot!(format!("{:#?}", switch_session_event));
+}
+
+#[test]
+#[ignore]
+pub fn disconnect_other_clients_plugins_command() {
+    let temp_folder = tempdir().unwrap(); // placed explicitly in the test scope because its
+                                          // destructor removes the directory
+    let plugin_host_folder = PathBuf::from(temp_folder.path());
+    let cache_path = plugin_host_folder.join("permissions_test.kdl");
+    let (plugin_thread_sender, server_receiver, screen_receiver, teardown) =
+        create_plugin_thread_with_server_receiver(Some(plugin_host_folder));
+    let plugin_should_float = Some(false);
+    let plugin_title = Some("test_plugin".to_owned());
+    let run_plugin = RunPlugin {
+        _allow_exec_host_cmd: false,
+        location: RunPluginLocation::File(PathBuf::from(&*PLUGIN_FIXTURE)),
+        configuration: Default::default(),
+    };
+    let tab_index = 1;
+    let client_id = 1;
+    let size = Size {
+        cols: 121,
+        rows: 20,
+    };
+    let received_screen_instructions = Arc::new(Mutex::new(vec![]));
+    let _screen_thread = grant_permissions_and_log_actions_in_thread_naked_variant!(
+        received_screen_instructions,
+        ScreenInstruction::Exit,
+        screen_receiver,
+        1,
+        &PermissionType::ChangeApplicationState,
+        cache_path,
+        plugin_thread_sender,
+        client_id
+    );
+    let received_server_instruction = Arc::new(Mutex::new(vec![]));
+    let server_thread = log_actions_in_thread!(
+        received_server_instruction,
+        ServerInstruction::DisconnectAllClientsExcept,
+        server_receiver,
+        1
+    );
+
+    let _ = plugin_thread_sender.send(PluginInstruction::AddClient(client_id));
+    let _ = plugin_thread_sender.send(PluginInstruction::Load(
+        plugin_should_float,
+        false,
+        plugin_title,
+        run_plugin,
+        tab_index,
+        None,
+        client_id,
+        size,
+        None,
+        false,
+    ));
+    std::thread::sleep(std::time::Duration::from_millis(500));
+
+    let _ = plugin_thread_sender.send(PluginInstruction::Update(vec![(
+        None,
+        Some(client_id),
+        Event::Key(Key::Ctrl('6')), // this triggers the enent in the fixture plugin
+    )]));
+    std::thread::sleep(std::time::Duration::from_millis(500));
+    teardown();
+    server_thread.join().unwrap(); // this might take a while if the cache is cold
+    let switch_session_event = received_server_instruction
+        .lock()
+        .unwrap()
+        .iter()
+        .rev()
+        .find_map(|i| {
+            if let ServerInstruction::DisconnectAllClientsExcept(..) = i {
+                Some(i.clone())
+            } else {
+                None
+            }
+        })
+        .clone();
+    assert_snapshot!(format!("{:#?}", switch_session_event));
+}
diff --git a/zellij-server/src/plugins/unit/snapshots/zellij_server__plugins__plugin_tests__disconnect_other_clients_plugins_command.snap b/zellij-server/src/plugins/unit/snapshots/zellij_server__plugins__plugin_tests__disconnect_other_clients_plugins_command.snap
new file mode 100644
index 00000000..d463df1c
--- /dev/null
+++ b/zellij-server/src/plugins/unit/snapshots/zellij_server__plugins__plugin_tests__disconnect_other_clients_plugins_command.snap
@@ -0,0 +1,10 @@
+---
+source: zellij-server/src/plugins/./unit/plugin_tests.rs
+assertion_line: 6131
+expression: "format!(\"{:#?}\", switch_session_event)"
+---
+Some(
+    DisconnectAllClientsExcept(
+        1,
+    ),
+)
diff --git a/zellij-server/src/plugins/unit/snapshots/zellij_server__plugins__plugin_tests__switch_session_plugin_command.snap b/zellij-server/src/plugins/unit/snapshots/zellij_server__plugins__plugin_tests__switch_session_plugin_command.snap
new file mode 100644
index 00000000..f254f039
--- /dev/null
+++ b/zellij-server/src/plugins/unit/snapshots/zellij_server__plugins__plugin_tests__switch_session_plugin_command.snap
@@ -0,0 +1,18 @@
+---
+source: zellij-server/src/plugins/./unit/plugin_tests.rs
+assertion_line: 6051
+expression: "format!(\"{:#?}\", switch_session_event)"
+---
+Some(
+    SwitchSession(
+        ConnectToSession {
+            name: Some(
+                "my_new_session",
+            ),
+            tab_position: None,
+            pane_id: None,
+            layout: None,
+        },
+        1,
+    ),
+)
diff --git a/zellij-server/src/plugins/unit/snapshots/zellij_server__plugins__plugin_tests__switch_session_with_layout_plugin_command.snap b/zellij-server/src/plugins/unit/snapshots/zellij_server__plugins__plugin_tests__switch_session_with_layout_plugin_command.snap
new file mode 100644
index 00000000..46f6819a
--- /dev/null
+++ b/zellij-server/src/plugins/unit/snapshots/zellij_server__plugins__plugin_tests__switch_session_with_layout_plugin_command.snap
@@ -0,0 +1,22 @@
+---
+source: zellij-server/src/plugins/./unit/plugin_tests.rs
+assertion_line: 6131
+expression: "format!(\"{:#?}\", switch_session_event)"
+---
+Some(
+    SwitchSession(
+        ConnectToSession {
+            name: Some(
+                "my_other_new_session",
+            ),
+            tab_position: None,
+            pane_id: None,
+            layout: Some(
+                BuiltIn(
+                    "compact",
+                ),
+            ),
+        },
+        1,
+    ),
+)
diff --git a/zellij-server/src/plugins/zellij_exports.rs b/zellij-server/src/plugins/zellij_exports.rs
index 8791e128..e6787c24 100644
--- a/zellij-server/src/plugins/zellij_exports.rs
+++ b/zellij-server/src/plugins/zellij_exports.rs
@@ -18,10 +18,14 @@ use std::{
 use wasmer::{imports, AsStoreMut, Function, FunctionEnv, FunctionEnvMut, Imports};
 use wasmer_wasi::WasiEnv;
 use zellij_utils::data::{
-    CommandType, ConnectToSession, HttpVerb, MessageToPlugin, PermissionStatus, PermissionType,
-    PluginPermission,
+    CommandType, ConnectToSession, HttpVerb, LayoutInfo, MessageToPlugin, PermissionStatus,
+    PermissionType, PluginPermission,
 };
 use zellij_utils::input::permission::PermissionCache;
+use zellij_utils::{
+    interprocess::local_socket::LocalSocketStream,
+    ipc::{ClientToServerMsg, IpcSenderWithContext},
+};
 
 use url::Url;
 
@@ -225,6 +229,7 @@ fn host_run_plugin_command(env: FunctionEnvMut<ForeignFunctionEnv>) {
                         connect_to_session.name,
                         connect_to_session.tab_position,
                         connect_to_session.pane_id,
+                        connect_to_session.layout,
                     )?,
                     PluginCommand::DeleteDeadSession(session_name) => {
                         delete_dead_session(session_name)?
@@ -252,6 +257,8 @@ fn host_run_plugin_command(env: FunctionEnvMut<ForeignFunctionEnv>) {
                         cli_pipe_output(env, pipe_name, output)?
                     },
                     PluginCommand::MessageToPlugin(message) => message_to_plugin(env, message)?,
+                    PluginCommand::DisconnectOtherClients => disconnect_other_clients(env),
+                    PluginCommand::KillSessions(session_list) => kill_sessions(session_list),
                 },
                 (PermissionStatus::Denied, permission) => {
                     log::error!(
@@ -900,6 +907,7 @@ fn switch_session(
     session_name: Option<String>,
     tab_position: Option<usize>,
     pane_id: Option<(u32, bool)>,
+    layout: Option<LayoutInfo>,
 ) -> Result<()> {
     // pane_id is (id, is_plugin)
     let err_context = || format!("Failed to switch session");
@@ -909,6 +917,7 @@ fn switch_session(
         name: session_name,
         tab_position,
         pane_id,
+        layout,
     };
     env.plugin_env
         .senders
@@ -1278,6 +1287,30 @@ fn rename_session(env: &ForeignFunctionEnv, new_session_name: String) {
     apply_action!(action, error_msg, env);
 }
 
+fn disconnect_other_clients(env: &ForeignFunctionEnv) {
+    let _ = env
+        .plugin_env
+        .senders
+        .send_to_server(ServerInstruction::DisconnectAllClientsExcept(
+            env.plugin_env.client_id,
+        ))
+        .context("failed to send disconnect other clients instruction");
+}
+
+fn kill_sessions(session_names: Vec<String>) {
+    for session_name in session_names {
+        let path = &*ZELLIJ_SOCK_DIR.join(&session_name);
+        match LocalSocketStream::connect(path) {
+            Ok(stream) => {
+                let _ = IpcSenderWithContext::new(stream).send(ClientToServerMsg::KillSession);
+            },
+            Err(e) => {
+                log::error!("Failed to kill session {}: {:?}", session_name, e);
+            },
+        };
+    }
+}
+
 // Custom panic handler for plugins.
 //
 // This is called when a panic occurs in a plugin. Since most panics will likely originate in the
@@ -1406,7 +1439,9 @@ fn check_command_permission(
         | PluginCommand::DeleteDeadSession(..)
         | PluginCommand::DeleteAllDeadSessions
         | PluginCommand::RenameSession(..)
-        | PluginCommand::RenameTab(..) => PermissionType::ChangeApplicationState,
+        | PluginCommand::RenameTab(..)
+        | PluginCommand::DisconnectOtherClients
+        | PluginCommand::KillSessions(..) => PermissionType::ChangeApplicationState,
         PluginCommand::UnblockCliPipeInput(..)
         | PluginCommand::BlockCliPipeInput(..)
         | PluginCommand::CliPipeOutput(..) => PermissionType::ReadCliPipes,