utils: Add message dialog to confirm leaving a room

po/POTFILES.in

@@ -108,6 +108,7 @@ src/session/view/sidebar/room_row.rs
 src/session/view/sidebar/row.rs
 src/shortcuts.ui
 src/user_facing_error.rs
-src/utils/media.rs
 src/utils/matrix.rs
+src/utils/media.rs
+src/utils/message_dialog.rs
 src/window.rs

src/utils/message_dialog.rs

@@ -0,0 +1,51 @@
+//! Common message dialogs.
+
+use adw::prelude::*;
+use gettextrs::gettext;
+
+use crate::session::model::{Room, RoomType};
+
+/// Show a dialog to confirm leaving a room.
+///
+/// This supports both leaving a joined room and rejecting an invite.
+pub async fn confirm_leave_room(room: &Room, transient_for: &gtk::Window) -> bool {
+    let (heading, body, response) = if room.category() == RoomType::Invited {
+        // We are rejecting an invite.
+        let heading = gettext("Decline Invite?");
+        let body = if room.is_join_rule_public() {
+            gettext("Do you really want to decline this invite? You can join this room on you own later.")
+        } else {
+            gettext(
+                "Do you really want to decline this invite? You won’t be able to join this room without it.",
+            )
+        };
+        let response = gettext("Decline");
+
+        (heading, body, response)
+    } else {
+        // We are leaving a room that was joined.
+        let heading = gettext("Leave Room?");
+        let body = if room.is_join_rule_public() {
+            gettext("Do you really want to leave this room? You can come back later.")
+        } else {
+            gettext(
+                "Do you really want to leave this room? You won’t be able to come back without an invitation.",
+            )
+        };
+        let response = gettext("Leave");
+
+        (heading, body, response)
+    };
+
+    // Ask for confirmation.
+    let confirm_dialog = adw::MessageDialog::builder()
+        .transient_for(transient_for)
+        .default_response("cancel")
+        .heading(heading)
+        .body(body)
+        .build();
+    confirm_dialog.add_responses(&[("cancel", &gettext("Cancel")), ("leave", &response)]);
+    confirm_dialog.set_response_appearance("leave", adw::ResponseAppearance::Destructive);
+
+    confirm_dialog.choose_future().await == "leave"
+}

src/utils/mod.rs

@@ -4,6 +4,7 @@ mod expression_list_model;
 pub mod macros;
 pub mod matrix;
 pub mod media;
+pub mod message_dialog;
 pub mod notifications;
 pub mod sourceview;
 pub mod template_callbacks;