feat: add Linux and Windows named-window routing

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packages/zig/build.zigmodified+10-0

Changes to packages/zig/build.zig

		⋯1,246 linesShow the 1,246 lines above this hunk@@ -1247,6 +1247,14 @@ pub fn build(b: *std.Build) void {
1247	1247	}),
1248	1248	});
1249	1249
	1250	+ const window_reply_target_tests = b.addTest(.{
	1251	+ .root_module = b.createModule(.{
	1252	+ .root_source_file = b.path("src/window_reply_target.zig"),
	1253	+ .target = target,
	1254	+ .optimize = optimize,
	1255	+ }),
	1256	+ });
	1257	+
1250	1258	// The shell bridge's argv construction: what a `spawn` actually runs.
1251	1259	// Untested until now, which is how it shipped parsing an `args` array and
1252	1260	// throwing it away.
		⋯447 linesShow the 447 lines above this hunk@@ -1700,6 +1708,7 @@ pub fn build(b: *std.Build) void {
1700	1708	const run_window_lifecycle_tests = b.addRunArtifact(window_lifecycle_tests);
1701	1709	const run_window_registry_tests = b.addRunArtifact(window_registry_tests);
1702	1710	const run_window_context_tests = b.addRunArtifact(window_context_tests);
	1711	+ const run_window_reply_target_tests = b.addRunArtifact(window_reply_target_tests);
1703	1712	const run_external_link_tests = b.addRunArtifact(external_link_tests);
1704	1713	const run_webview_recovery_tests = b.addRunArtifact(webview_recovery_tests);
1705	1714	const run_request_context_tests = b.addRunArtifact(request_context_tests);
		⋯142 linesShow the 142 lines above this hunk@@ -1848,6 +1857,7 @@ pub fn build(b: *std.Build) void {
1848	1857	test_step.dependOn(&run_window_lifecycle_tests.step);
1849	1858	test_step.dependOn(&run_window_registry_tests.step);
1850	1859	test_step.dependOn(&run_window_context_tests.step);
	1860	+ test_step.dependOn(&run_window_reply_target_tests.step);
1851	1861	test_step.dependOn(&run_external_link_tests.step);
1852	1862	test_step.dependOn(&run_webview_recovery_tests.step);
1853	1863	test_step.dependOn(&run_request_context_tests.step);

packages/zig/src/linux.zigmodified+14-11

Changes to packages/zig/src/linux.zig

		@@ -1,4 +1,6 @@
1	1	const std = ;
	2	+const window_context = ;
	3	+const window_reply_target = ;
2	4
3	5	// Linux implementation using GTK3 and WebKit2GTK 4.1.
4	6	// Requires: libgtk-3-dev, libwebkit2gtk-4.1-dev
		⋯484 linesShow the 484 lines above this hunk@@ -489,28 +491,29 @@ pub const App = struct {
489	491	}
490	492	};
491	493
492		-/// Evaluate JavaScript in the current webview (cross-platform bridge helper).
493		-/// Uses the most recently registered window's webview from the window registry.
	494	+/// Evaluate JavaScript in the page that sent the current bridge message.
	495	+/// Native callers without a sender continue to use the latest live window.
494	496	pub fn evalJS(script: []const u8) !void {
495		- // Find the most recently registered window's webview
	497	+ var live: [window_registry.len]usize = undefined;
	498	+ var live_len: usize = 0;
496	499	var latest_id: u32 = 0;
497		- var latest_webview: ?*anyopaque = null;
	500	+ var fallback: ?usize = null;
498	501	for (window_registry) |entry| {
499	502	if (entry) |e| {
	503	+ live[live_len] = @intFromPtr(e.webview);
	504	+ live_len += 1;
500	505	if (e.id > latest_id) {
501	506	latest_id = e.id;
502		- latest_webview = e.webview;
	507	+ fallback = @intFromPtr(e.webview);
503	508	}
504	509	}
505	510	}
506	511
507		- if (latest_webview) |webview| {
508		- const script_z = .dupeZ(std.heap.c_allocator, u8, script) catch return error.OutOfMemory;
509		- defer std.heap.c_allocator.free(script_z);
510		- webkit_web_view_run_javascript(webview, script_z, null, null, null);
511		- } else {
	512	+ const target = window_reply_target.select(live[0..live_len], window_context.currentWebView(), fallback) orelse
512	513	return error.NoWebView;
513		- }
	514	+ const script_z = try .dupeZ(std.heap.c_allocator, u8, script);
	515	+ defer std.heap.c_allocator.free(script_z);
	516	+ webkit_web_view_run_javascript(@ptrFromInt(target), script_z, null, null, null);
514	517	}
515	518
516	519	// Legacy API compatibility

packages/zig/src/window_reply_target.zigadded+35-0

Changes to packages/zig/src/window_reply_target.zig

		@@ -0,0 +1,35 @@
	1	+//! Select a live desktop webview for a bridge reply.
	2	+//!
	3	+//! A reply made while serving a page belongs to that page. If its webview was
	4	+//! destroyed during a nested run loop, sending the reply to the latest window
	5	+//! would settle somebody else's call instead. Only native callers without a
	6	+//! sender context may use the platform's fallback webview.
	7	+
	8	+const std = ;
	9	+
	10	+pub fn select(live_webviews: []const usize, sender: ?usize, fallback: ?usize) ?usize {
	11	+ const requested = sender orelse fallback orelse return null;
	12	+ if (requested == 0) return null;
	13	+ for (live_webviews) |webview| {
	14	+ if (webview == requested) return webview;
	15	+ }
	16	+ return null;
	17	+}
	18	+
	19	+test "a page reply targets its own live webview" {
	20	+ const live = [_]usize{ 0x1000, 0x2000 };
	21	+ try std.testing.expectEqual(@as(?usize, 0x1000), select(&live, 0x1000, 0x2000));
	22	+}
	23	+
	24	+test "a destroyed sender never falls through to another page" {
	25	+ const live = [_]usize{0x2000};
	26	+ try std.testing.expectEqual(@as(?usize, null), select(&live, 0x1000, 0x2000));
	27	+}
	28	+
	29	+test "a native caller uses only a live fallback" {
	30	+ const live = [_]usize{ 0x1000, 0x2000 };
	31	+ try std.testing.expectEqual(@as(?usize, 0x2000), select(&live, null, 0x2000));
	32	+ try std.testing.expectEqual(@as(?usize, null), select(&live, null, 0x3000));
	33	+ try std.testing.expectEqual(@as(?usize, null), select(&live, null, null));
	34	+ try std.testing.expectEqual(@as(?usize, null), select(&live, null, 0));
	35	+}