Emscripten: Sync session with the website one

Also fix a cursed length-related problem with passing strings from JS to C++.

src/client/AuthUserCommon.cpp

@@ -0,0 +1,30 @@
+#include "Client.h"
+#include "prefs/GlobalPrefs.h"
+
+void Client::LoadAuthUser()
+{
+	auto &prefs = GlobalPrefs::Ref();
+	authUser.UserID = prefs.Get("User.ID", 0);
+	authUser.Username = prefs.Get("User.Username", ByteString(""));
+	authUser.SessionID = prefs.Get("User.SessionID", ByteString(""));
+	authUser.SessionKey = prefs.Get("User.SessionKey", ByteString(""));
+	authUser.UserElevation = prefs.Get("User.Elevation", User::ElevationNone);
+}
+
+void Client::SaveAuthUser()
+{
+	auto &prefs = GlobalPrefs::Ref();
+	Prefs::DeferWrite dw(prefs);
+	if (authUser.UserID)
+	{
+		prefs.Set("User.ID", authUser.UserID);
+		prefs.Set("User.SessionID", authUser.SessionID);
+		prefs.Set("User.SessionKey", authUser.SessionKey);
+		prefs.Set("User.Username", authUser.Username);
+		prefs.Set("User.Elevation", authUser.UserElevation);
+	}
+	else
+	{
+		prefs.Clear("User");
+	}
+}

src/client/AuthUserEmscripten.cpp

@@ -0,0 +1,42 @@
+#include "Client.h"
+#include "prefs/GlobalPrefs.h"
+#include <emscripten.h>
+
+void Client::LoadAuthUser()
+{
+	std::optional<ByteString> newUsername;
+	if (EM_ASM_INT({
+		return document.querySelector("#PowderSessionInfo [name='Username']") ? 1 : 0;
+	}))
+	{
+		newUsername = ByteString(std::unique_ptr<char, decltype(&free)>((char *)EM_ASM_PTR({
+			return stringToNewUTF8(document.querySelector("#PowderSessionInfo [name='Username']").value);
+		}), free).get());
+	}
+	std::optional<ByteString> newSessionKey;
+	if (EM_ASM_INT({
+		return document.querySelector("#PowderSessionInfo [name='SessionKey']") ? 1 : 0;
+	}))
+	{
+		newSessionKey = ByteString(std::unique_ptr<char, decltype(&free)>((char *)EM_ASM_PTR({
+			return stringToNewUTF8(document.querySelector("#PowderSessionInfo [name='SessionKey']").value);
+		}), free).get());
+	}
+	if (newUsername && newSessionKey)
+	{
+		authUser.UserID = -1; // Not quite valid but evaluates to true and that's all that matters for this codebase.
+		authUser.Username = *newUsername;
+		authUser.SessionID = "(invalid)";
+		authUser.SessionKey = *newSessionKey;
+		authUser.UserElevation = User::ElevationNone; // We don't deal with this in the browser.
+	}
+	else
+	{
+		authUser.UserID = 0;
+	}
+}
+
+void Client::SaveAuthUser()
+{
+	// Nothing is; the cookie headers in the login and logout responses take care of state management.
+}

src/client/Client.cpp

@@ -32,12 +32,8 @@ Client::Client():
 	updateAvailable(false),
 	authUser(0, "")
 {
+	LoadAuthUser();
 	auto &prefs = GlobalPrefs::Ref();
-	authUser.UserID = prefs.Get("User.ID", 0);
-	authUser.Username = prefs.Get("User.Username", ByteString(""));
-	authUser.SessionID = prefs.Get("User.SessionID", ByteString(""));
-	authUser.SessionKey = prefs.Get("User.SessionKey", ByteString(""));
-	authUser.UserElevation = prefs.Get("User.Elevation", User::ElevationNone);
 	firstRun = !prefs.BackedByFile();
 }
 
@@ -239,22 +235,7 @@ Client::~Client()
 void Client::SetAuthUser(User user)
 {
 	authUser = user;
-	{
+	SaveAuthUser();
-		auto &prefs = GlobalPrefs::Ref();
-		Prefs::DeferWrite dw(prefs);
-		if (authUser.UserID)
-		{
-			prefs.Set("User.ID", authUser.UserID);
-			prefs.Set("User.SessionID", authUser.SessionID);
-			prefs.Set("User.SessionKey", authUser.SessionKey);
-			prefs.Set("User.Username", authUser.Username);
-			prefs.Set("User.Elevation", authUser.UserElevation);
-		}
-		else
-		{
-			prefs.Clear("User");
-		}
-	}
 	notifyAuthUserChanged();
 }
 

src/client/Client.h

@@ -53,6 +53,9 @@ private:
 	void MigrateStampsDef();
 	void WriteStamps();
 
+	void LoadAuthUser();
+	void SaveAuthUser();
+
 public:
 
 	std::vector<ClientListener*> listeners;

src/client/http/GetCommentsRequest.cpp

@@ -21,7 +21,7 @@ namespace http
 				comments.push_back({
 					comment["Username"].asString(),
 					User::ElevationFromString(comment["Elevation"].asString()),
-					ByteString(comment["UserID"].asString()).ToNumber<int>() == user.UserID,
+					comment["Username"].asString() == user.Username,
 					comment["IsBanned"].asBool(),
 					ByteString(comment["Text"].asString()).FromUtf8(),
 				});

src/client/http/Request.cpp

@@ -60,7 +60,7 @@ namespace http
 	void Request::AuthHeaders(ByteString ID, ByteString session)
 	{
 		assert(handle->state == RequestHandle::ready);
-		if (ID.size())
+		if (ID.size() && ID != "-1") // -1 is an emscripten hack, see AuthUserEmscripten.cpp
 		{
 			if (session.size())
 			{

src/client/http/requestmanager/Emscripten.cpp

@@ -252,7 +252,6 @@ namespace http
 				method: request.fetchMethod,
 				headers: request.fetchHeaders,
 				body: request.fetchBody,
-				credentials: 'omit',
 				signal: request.fetchController.signal,
 			}).then(response => {
 				request.statusEarly = response.status;
@@ -344,18 +343,12 @@ namespace http
 			handle->responseHeaders.resize(headerCount);
 			for (auto i = 0; i < headerCount; ++i)
 			{
-				handle->responseHeaders[i].name.resize(EM_ASM_INT({
+				handle->responseHeaders[i].name = ByteString(std::unique_ptr<char, decltype(&free)>((char *)EM_ASM_PTR({
-					return lengthBytesUTF8(Module.emscriptenRequestManager.requests[$0].responseHeaders[$1].name);
+					return stringToNewUTF8(Module.emscriptenRequestManager.requests[$0].responseHeaders[$1].name);
-				}, handle->id, i));
+				}, handle->id, i), free).get());
-				EM_ASM({
+				handle->responseHeaders[i].value = ByteString(std::unique_ptr<char, decltype(&free)>((char *)EM_ASM_PTR({
-					stringToUTF8(Module.emscriptenRequestManager.requests[$0].responseHeaders[$1].name, $2, $3);
+					return stringToNewUTF8(Module.emscriptenRequestManager.requests[$0].responseHeaders[$1].value);
-				}, handle->id, i, &handle->responseHeaders[i].name[0], handle->responseHeaders[i].name.size());
+				}, handle->id, i), free).get());
-				handle->responseHeaders[i].value.resize(EM_ASM_INT({
-					return lengthBytesUTF8(Module.emscriptenRequestManager.requests[$0].responseHeaders[$1].value);
-				}, handle->id, i));
-				EM_ASM({
-					stringToUTF8(Module.emscriptenRequestManager.requests[$0].responseHeaders[$1].value, $2, $3);
-				}, handle->id, i, &handle->responseHeaders[i].value[0], handle->responseHeaders[i].value.size());
 			}
 			handle->gotResponse = true;
 			HandleWake();

src/client/meson.build

@@ -7,6 +7,11 @@ client_files = files(
 	'GameSave.cpp',
 	'User.cpp',
 )
+if host_platform == 'emscripten'
+	client_files += files('AuthUserEmscripten.cpp')
+else
+	client_files += files('AuthUserCommon.cpp')
+endif
 
 subdir('http')