Add zig listener support to netsurf event handler

src/browser/browser.zig

@@ -134,6 +134,10 @@ pub const Session = struct {
     storage_shed: storage.Shed,
     cookie_jar: storage.CookieJar,
 
+    // arbitrary that we pass to the inspector, which the inspector will include
+    // in any response/event that it emits.
+    aux_data: ?[]const u8 = null,
+
     page: ?Page = null,
     http_client: *http.Client,
 
@@ -158,6 +162,7 @@ pub const Session = struct {
         const allocator = app.allocator;
         self.* = .{
             .app = app,
+            .aux_data = null,
             .browser = browser,
             .notify_ctx = any_ctx,
             .inspector = undefined,
@@ -250,8 +255,12 @@ pub const Session = struct {
         // load polyfills
         try polyfill.load(self.arena.allocator(), self.executor);
 
+        if (aux_data) |ad| {
+            self.aux_data = try self.arena.allocator().dupe(u8, ad);
+        }
+
         // inspector
-        self.contextCreated(page, aux_data);
+        self.contextCreated(page);
 
         return page;
     }
@@ -279,9 +288,28 @@ pub const Session = struct {
         return &(self.page orelse return null);
     }
 
-    fn contextCreated(self: *Session, page: *Page, aux_data: ?[]const u8) void {
+    fn pageNavigate(self: *Session, url_string: []const u8) !void {
+        // currently, this is only called from the page, so let's hope
+        // it isn't null!
+        std.debug.assert(self.page != null);
+
+        // can't use the page arena, because we're about to reset it
+        // and don't want to use the session's arena, because that'll start to
+        // look like a leak if we navigate from page to page a lot.
+        var buf: [1024]u8 = undefined;
+        var fba = std.heap.FixedBufferAllocator.init(&buf);
+        const url = try self.page.?.url.?.resolve(fba.allocator(), url_string);
+
+        self.removePage();
+        var page = try self.createPage(null);
+        return page.navigate(url, .{
+            .reason = .anchor,
+        });
+    }
+
+    fn contextCreated(self: *Session, page: *Page) void {
         log.debug("inspector context created", .{});
-        self.inspector.contextCreated(self.executor, "", (page.origin() catch "://") orelse "://", aux_data);
+        self.inspector.contextCreated(self.executor, "", (page.origin() catch "://") orelse "://", self.aux_data);
     }
 
     fn notify(self: *const Session, notification: *const Notification) void {
@@ -361,7 +389,7 @@ pub const Page = struct {
     // spec reference: https://html.spec.whatwg.org/#document-lifecycle
     // - aux_data: extra data forwarded to the Inspector
     // see Inspector.contextCreated
-    pub fn navigate(self: *Page, request_url: URL, aux_data: ?[]const u8) !void {
+    pub fn navigate(self: *Page, request_url: URL, opts: NavigateOpts) !void {
         const arena = self.arena;
         const session = self.session;
 
@@ -387,7 +415,12 @@ pub const Page = struct {
         var request = try self.newHTTPRequest(.GET, url, .{ .navigation = true });
         defer request.deinit();
 
-        session.notify(&.{ .page_navigate = .{ .url = url, .timestamp = timestamp() } });
+        session.notify(&.{ .page_navigate = .{
+            .url = url,
+            .reason = opts.reason,
+            .timestamp = timestamp(),
+        } });
+
         var response = try request.sendSync(.{});
 
         // would be different than self.url in the case of a redirect
@@ -417,7 +450,7 @@ pub const Page = struct {
         var mime = try Mime.parse(arena, ct);
 
         if (mime.isHTML()) {
-            try self.loadHTMLDoc(&response, mime.charset orelse "utf-8", aux_data);
+            try self.loadHTMLDoc(&response, mime.charset orelse "utf-8");
         } else {
             log.info("non-HTML document: {s}", .{ct});
             var arr: std.ArrayListUnmanaged(u8) = .{};
@@ -428,44 +461,14 @@ pub const Page = struct {
             self.raw_data = arr.items;
         }
 
-        session.notify(&.{ .page_navigated = .{ .url = url, .timestamp = timestamp() } });
-    }
-
-    pub const ClickResult = union(enum) {
-        navigate: std.Uri,
-    };
-
-    pub const MouseEvent = struct {
-        x: i32,
-        y: i32,
-        type: Type,
-
-        const Type = enum {
-            pressed,
-            released,
-        };
-    };
-
-    pub fn mouseEvent(self: *Page, me: MouseEvent) !void {
-        if (me.type != .pressed) {
-            return;
-        }
-
-        const element = self.renderer.getElementAtPosition(me.x, me.y) orelse return;
-
-        const event = try parser.mouseEventCreate();
-        defer parser.mouseEventDestroy(event);
-        try parser.mouseEventInit(event, "click", .{
-            .bubbles = true,
-            .cancelable = true,
-            .x = me.x,
-            .y = me.y,
-        });
-        _ = try parser.elementDispatchEvent(element, @ptrCast(event));
+        session.notify(&.{ .page_navigated = .{
+            .url = url,
+            .timestamp = timestamp(),
+        } });
     }
 
     // https://html.spec.whatwg.org/#read-html
-    fn loadHTMLDoc(self: *Page, reader: anytype, charset: []const u8, aux_data: ?[]const u8) !void {
+    fn loadHTMLDoc(self: *Page, reader: anytype, charset: []const u8) !void {
         const arena = self.arena;
 
         // start netsurf memory arena.
@@ -481,6 +484,16 @@ pub const Page = struct {
         // save a document's pointer in the page.
         self.doc = doc;
 
+        const document_element = (try parser.documentGetDocumentElement(doc)) orelse return error.DocumentElementError;
+        try parser.eventTargetAddZigListener(
+            parser.toEventTarget(parser.Element, document_element),
+            arena,
+            "click",
+            windowClicked,
+            self,
+            false,
+        );
+
         // TODO set document.readyState to interactive
         // https://html.spec.whatwg.org/#reporting-document-loading-status
 
@@ -497,7 +510,7 @@ pub const Page = struct {
         // https://html.spec.whatwg.org/#read-html
 
         // inspector
-        session.contextCreated(self, aux_data);
+        session.contextCreated(self);
 
         {
             // update the sessions state
@@ -728,6 +741,61 @@ pub const Page = struct {
         return request;
     }
 
+    pub const MouseEvent = struct {
+        x: i32,
+        y: i32,
+        type: Type,
+
+        const Type = enum {
+            pressed,
+            released,
+        };
+    };
+
+    pub fn mouseEvent(self: *Page, me: MouseEvent) !void {
+        if (me.type != .pressed) {
+            return;
+        }
+
+        const element = self.renderer.getElementAtPosition(me.x, me.y) orelse return;
+
+        const event = try parser.mouseEventCreate();
+        defer parser.mouseEventDestroy(event);
+        try parser.mouseEventInit(event, "click", .{
+            .bubbles = true,
+            .cancelable = true,
+            .x = me.x,
+            .y = me.y,
+        });
+        _ = try parser.elementDispatchEvent(element, @ptrCast(event));
+    }
+
+    fn windowClicked(ctx: *anyopaque, event: *parser.Event) void {
+        const self: *Page = @alignCast(@ptrCast(ctx));
+        self._windowClicked(event) catch |err| {
+            log.err("window click handler: {}", .{err});
+        };
+    }
+
+    fn _windowClicked(self: *Page, event: *parser.Event) !void {
+        const target = (try parser.eventTarget(event)) orelse return;
+
+        const node = parser.eventTargetToNode(target);
+        if (try parser.nodeType(node) != .element) {
+            return;
+        }
+
+        const html_element: *parser.ElementHTML = @ptrCast(node);
+        switch (try parser.elementHTMLGetTagType(html_element)) {
+            .a => {
+                const element: *parser.Element = @ptrCast(node);
+                const href = (try parser.elementGetAttribute(element, "href")) orelse return;
+                return self.session.pageNavigate(href);
+            },
+            else => {},
+        }
+    }
+
     const Script = struct {
         element: *parser.Element,
         kind: Kind,
@@ -792,8 +860,17 @@ pub const Page = struct {
     };
 };
 
+pub const NavigateReason = enum {
+    anchor,
+    address_bar,
+};
+
+const NavigateOpts = struct {
+    reason: NavigateReason = .address_bar,
+};
+
 // provide very poor abstration to the rest of the code. In theory, we can change
-// the FlatRendere to a different implementation, and it'll all just work.
+// the FlatRenderer to a different implementation, and it'll all just work.
 pub const Renderer = FlatRenderer;
 
 // This "renderer" positions elements in a single row in an unspecified order.

src/browser/dom/mutation_observer.zig

@@ -104,15 +104,15 @@ pub const MutationObserver = struct {
                 arena,
                 "DOMNodeInserted",
                 EventHandler,
-                .{ .cbk = self.cbk, .data = o, .deinitFunc = deinitFunc },
+                .{ .cbk = self.cbk, .ctx = o, .deinitFunc = deinitFunc },
                 false,
             );
             try parser.eventTargetAddEventListener(
                 parser.toEventTarget(parser.Node, node),
                 arena,
                 "DOMNodeRemoved",
                 EventHandler,
-                .{ .cbk = self.cbk, .data = o, .deinitFunc = deinitFunc },
+                .{ .cbk = self.cbk, .ctx = o, .deinitFunc = deinitFunc },
                 false,
             );
         }
@@ -122,7 +122,7 @@ pub const MutationObserver = struct {
                 arena,
                 "DOMAttrModified",
                 EventHandler,
-                .{ .cbk = self.cbk, .data = o, .deinitFunc = deinitFunc },
+                .{ .cbk = self.cbk, .ctx = o, .deinitFunc = deinitFunc },
                 false,
             );
         }
@@ -132,7 +132,7 @@ pub const MutationObserver = struct {
                 arena,
                 "DOMCharacterDataModified",
                 EventHandler,
-                .{ .cbk = self.cbk, .data = o, .deinitFunc = deinitFunc },
+                .{ .cbk = self.cbk, .ctx = o, .deinitFunc = deinitFunc },
                 false,
             );
         }
@@ -142,7 +142,7 @@ pub const MutationObserver = struct {
                 arena,
                 "DOMSubtreeModified",
                 EventHandler,
-                .{ .cbk = self.cbk, .data = o, .deinitFunc = deinitFunc },
+                .{ .cbk = self.cbk, .ctx = o, .deinitFunc = deinitFunc },
                 false,
             );
         }
@@ -261,7 +261,7 @@ const EventHandler = struct {
         return false;
     }
 
-    fn handle(evt: ?*parser.Event, data: parser.EventHandlerData) void {
+    fn handle(evt: ?*parser.Event, data: *const parser.JSEventHandlerData) void {
         if (evt == null) return;
 
         var mrs: MutationRecords = .{};
@@ -277,7 +277,7 @@ const EventHandler = struct {
         const node = parser.eventTargetToNode(et);
 
         // retrieve the observer from the data.
-        const o: *MutationObserver.Observer = @ptrCast(@alignCast(data.data));
+        const o: *MutationObserver.Observer = @ptrCast(@alignCast(data.ctx));
 
         if (!apply(o, node)) return;
 

src/browser/events/event.zig

@@ -136,7 +136,7 @@ pub const Event = struct {
 };
 
 pub const EventHandler = struct {
-    fn handle(event: ?*parser.Event, data: parser.EventHandlerData) void {
+    fn handle(event: ?*parser.Event, data: *const parser.JSEventHandlerData) void {
         var result: Callback.Result = undefined;
         data.cbk.tryCall(.{if (event) |evt| Event.toInterface(evt) catch unreachable else null}, &result) catch {
             log.err("event handler error: {s}", .{result.exception});

src/browser/html/elements.zig

@@ -130,6 +130,18 @@ pub const HTMLElement = struct {
         // attach the text node.
         _ = try parser.nodeAppendChild(n, @as(*parser.Node, @ptrCast(t)));
     }
+
+    pub fn _click(e: *parser.ElementHTML) !void {
+        const event = try parser.mouseEventCreate();
+        defer parser.mouseEventDestroy(event);
+        try parser.mouseEventInit(event, "click", .{
+            .x = 0,
+            .y = 0,
+            .bubbles = true,
+            .cancelable = true,
+        });
+        _ = try parser.elementDispatchEvent(@ptrCast(e), @ptrCast(event));
+    }
 };
 
 // Deprecated HTMLElements in Chrome (2023/03/15)
@@ -982,4 +994,12 @@ test "Browser.HTML.Element" {
         .{ "document.getElementById('content').innerText", "foo" },
         .{ "document.getElementById('content').innerHTML = backup; true;", "true" },
     }, .{});
+
+    try runner.testCases(&.{
+        .{ "let click_count = 0;", "undefined" },
+        .{ "let clickCbk = function() { click_count++ }", "undefined" },
+        .{ "document.getElementById('content').addEventListener('click', clickCbk);", "undefined" },
+        .{ "document.getElementById('content').click()", "undefined" },
+        .{ "click_count", "1" },
+    }, .{});
 }