From f59320b1a0e70ef0f34eeed42a6f56b813c215c0 Mon Sep 17 00:00:00 2001
From: oracola91 <118899664+oracola91@users.noreply.github.com>
Date: Thu, 15 Oct 2026 18:36:56 +0300
Subject: [PATCH] fix(web): host mode needs a parent page on the same origin

With ?host=parent, saves are posted to the parent with the app's own
origin as the target. A framing page on another origin never gets them:
the browser drops each message without an error, post() returns Ok, and
the document is marked saved and the leave-page warning cleared (#2167).

Bridge::new now returns None unless the parent's origin is the app's
own (reading another origin's location throws, which is None too). The
app then runs as if unframed and saves download, and a console warning
says why. Same-origin embedding is unchanged.
---
 apps/pdfcraft-web/src/main.rs | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/apps/pdfcraft-web/src/main.rs b/apps/pdfcraft-web/src/main.rs
index a46a4674b9..73d14f4a6c 100644
--- a/apps/pdfcraft-web/src/main.rs
+++ b/apps/pdfcraft-web/src/main.rs
@@ -70,6 +70,10 @@ fn main() {
                         app.host_save = Some(bridge.save_fn());
                         app.host_dirty = Some(bridge.dirty_fn());
                         bridge.post_ready();
+                    } else if query_param("host").as_deref() == Some("parent") {
+                        eframe::web_sys::console::warn_1(
+                            &"PdfCraft: ?host=parent needs a framing page on the same origin; saves download instead".into(),
+                        );
                     }
                     Ok(Box::new(app))
                 }),
@@ -130,7 +134,8 @@ async fn fetch_bytes(url: &str) -> Result<Vec<u8>, String> {
 /// - `pdfcraft:dirty` (to the parent): `{ dirty }` whenever unsaved work appears or goes away.
 /// - `pdfcraft:failed` (to the parent): `{ error }` when the app couldn't start.
 ///
-/// Only the parent window on the app's own origin is heard or answered.
+/// Only the parent window on the app's own origin is heard or answered. With a parent on
+/// another origin there is no bridge: the app runs as if unframed and saves download.
 #[cfg(target_arch = "wasm32")]
 mod host {
     use eframe::wasm_bindgen::{JsCast, JsValue, closure::Closure};
@@ -143,7 +148,9 @@ mod host {
     }
 
     impl Bridge {
-        /// `None` when the page isn't framed (there is no parent to talk to).
+        /// `None` when the page isn't framed (there is no parent to talk to), or when the parent
+        /// is on another origin: messages only go to this origin, so the browser would drop
+        /// every save without an error while the document showed as saved (#2167).
         pub fn new() -> Option<Self> {
             let window = web_sys::window()?;
             let parent = window.parent().ok().flatten()?;
@@ -151,6 +158,10 @@ mod host {
                 return None;
             }
             let origin = window.location().origin().ok()?;
+            // Reading another origin's location throws, which is `None` too.
+            if parent.location().origin().ok()? != origin {
+                return None;
+            }
             Some(Self { window, parent, origin })
         }