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Author SHA1 Message Date
jaap-jan c5dec2d68e Measure the vault column instead of arguing about it
Nothing in this repository loaded a .axaml, so the one class of defect this
window has actually shipped — a control arranged past the edge of its container,
where it cannot be clicked — was the one class nothing could catch. The setup
screens rendered sliced once, with their buttons unreachable. The vault column is
the next candidate: 340 pixels wide, two lists and two editors, and the only
thing keeping it from clipping its own Save button at the window's 520-pixel
minimum is a state rule that one editor may be open at a time.

That rule was added on the strength of an argument. This adds an
Avalonia.Headless project that lays real XAML out at a real size and reports
what a user could not reach, and the argument is now a number: with both editors
open the column overflows, so the rule is load-bearing rather than defensive.
BothEditorsAtOnce_DoNotFit_WhichIsWhyTheRuleExists is the test, and it says what
to do if it ever starts passing — the column has room, so delete the rule, not
the test.

Two findings arrived by measuring rather than by reasoning, and the first one
changed the design.

MainWindow cannot be shown headlessly at all. Showing it attaches the terminal's
NativeWebView, whose Win32 adapter initialises WebView2 on attach, and WebView2
refuses a non-STA thread — which is exactly why Program.Main carries [STAThread]
and is written down in that comment. A HeadlessUnitTestSession owns its
dispatcher thread and offers no apartment choice, so the whole window is out of
reach at any size. That is pinned as a test asserting RPC_E_CHANGED_MODE by
HResult rather than by message, so a future Avalonia that makes the adapter lazy
will fail it and the harness can be widened.

So the column had to become its own control to be measurable, which is the
extraction the type-selector rework wanted anyway. Keyboard release moved with
it: MainWindow used to call Focus() on HostList by name, and now asks
VaultColumn.KeyboardTarget. The window decides that the keyboard should leave the
terminal and the column decides where it lands — which is the seam the rework
needs, because once the column shows one list at a time, "which list owns the
keyboard" is a question only the column can answer.

The second finding is the way this kind of test lies quietly. The hint class
lived in MainWindow.Styles and carries TextWrapping. A Window's styles reach its
whole tree, so nothing about the application depended on where it lived — but a
control laid out on its own loses them, and every hint paragraph would have
measured as a single line. The harness would have passed while measuring heights
that were all too small. The three shared classes now live in App.axaml, which
changes no rendering and makes the measurement honest.

The detector is calibrated in both directions, because a clipping detector that
never fires reads as a guarantee: a deliberately clipped Save button is caught by
name, and a list longer than its viewport is exempt. Scrolling is how a list is
supposed to handle more rows than fit, and without that exemption the host list
would fail the moment it had content. It also mis-fired once and the rule is
narrower for it — an empty ListBox is zero pixels tall and correct, so "arranged
with no size" now applies only to controls the theme gives a height to.

Skia rather than the headless drawing stub, deliberately. The stub's font manager
invents glyph metrics, and text height is an input to every stacked panel in this
column, so measuring against it would produce numbers that are self-consistent
and unrelated to the application.

A separate test project rather than more tests in DodoSSH.Client.App.Tests.
Avalonia's application, dispatcher and platform are process-global singletons
initialised once, and that project's identity is the shell's state machine
without Avalonia — the whole reason sign-in is a delegate. The fakes needed to
reach a real unlocked vault are shared from DodoSSH.Client.Session.Tests by
source link: a project reference would make one test project a library of
another, and a copy would be a third implementation of the same decision table
drifting from the other two.

855 tests green, 10 of them new. Zero warnings, dotnet format clean.

Not done, and this is groundwork rather than the item itself: the type selector.
The column still holds both lists at once, so a third item type would still
recreate the defect the one-editor rule works around. What is different is that
the rework can now be checked instead of eyeballed — including the claim it is
being made for, that one editor at a time stops being a runtime rule and becomes
a fact about what is in the visual tree.

What this harness will never catch is the terminal's native child window
compositing over Avalonia content. That is a Win32 property of a real window, no
headless surface reproduces it, and it is the reason the WebView is collapsed
rather than covered.
2026-07-30 11:34:09 +02:00
jaap-jan dbddbcd711 Hand the terminal the keyboard on connect, and take it back on lock
After a successful connect the first keystrokes went to the shell's UI rather
than the remote shell. The page's own term.focus() focuses the textarea inside
the document, which does nothing while the window's keyboard focus is still on
the Connect button, so the terminal had to be clicked before it would accept
anything.

The obvious guess about the fix — that reaching a native child window needs
SetFocus through P/Invoke — is backwards, and measuring it first is what kept
this small. NativeWebView overrides Focusable to true and its OnGotFocus calls
the adapter's Focus(), which on Windows is
ICoreWebView2Controller::MoveFocus(PROGRAMMATIC). So a plain Avalonia
Terminal.Focus() really does move Win32 focus into WebView2. Measured in a
standalone harness with no DodoSSH code, on the same 340,* grid as the shell,
reporting GetFocus() and the page's own document.hasFocus() at each step: focus
lands on the Chrome_WidgetWin_1 child and the page reports hasFocus: true.

It is the return trip the package does not implement. OnLostFocus calls the
adapter's ResignFocus(), and on Windows that method body is empty, so Avalonia's
focus and Win32's diverge: after textBox.Focus() the focused element is the text
box while the keyboard is still on WebView2 — a caret that silently receives
nothing. Window.Activate() and Window.Focus() were both measured and neither
recovers it, so the hand-back is a SetFocus on the top-level, in
Views/NativeKeyboardFocus.cs. A real mouse click does recover it, because
Avalonia's window sets focus on pointer input, which is why this is invisible to
anyone who clicks before typing.

That turned up a worse defect than the one being fixed, and it shipped in
0500e43. Collapsing the WebView does not release the keyboard: focus stays on
the hidden holder — measured held by a window reporting visible=False — while
Avalonia's focused element becomes (none). So a user who had clicked the
terminal and then pressed Lock got an unlock screen that swallowed the
passphrase. Locking now hands the keyboard back and focuses that box.

Ctrl+Shift+F6 is the way out for someone using only a keyboard. It has to be
handled in terminal.js and posted to the host as a web message, because once the
child window owns Win32 focus Avalonia receives no key events and no KeyBinding
could fire; the package also subscribes MoveFocusRequested and discards it, so
there is no Tab-out to lean on. Not Escape, which vim alone rules out, and not a
bare F6, which TUIs bind — Ctrl+Shift is the range terminal emulators
conventionally keep for themselves and never forward to the remote. Verified
rather than assumed: the posted string arrives verbatim in Body, and the chord
reaches the page as F6 with both modifiers.

Order matters and is now recorded. Focus() on a collapsed control is a measured
no-op and is not replayed when it is revealed, so focus survives a lock/unlock
cycle only because a session can be opened solely from an unlocked vault, which
is what reveals the control in the first place.

The view models still reference no view. VaultViewModel raises SessionOpened on
the success path only, the shell forwards it as TerminalSessionOpened through the
generated OnVaultChanged hook so unlock, lock and dispose all attach and detach
in one place, and the view holds the whole focus policy. An event rather than a
bound flag because connecting a second host while one is open has to move focus
again, and no state change describes that.

Three tests, and what they do not cover is the point. They cover the plumbing:
focus is asked for once per session, a failed connect does not ask at all — a
host-key prompt needs the keyboard on its own buttons — and locking stops the
forwarding. They cannot cover the focus call, because headless Avalonia has no
native window, so a headless test would focus correctly and confirm the wrong
belief; that is measured in the harness and written down in docs instead.
Dropping the forwarding fails two of them and dropping the detach fails one;
deleting the raise outright does not compile, since the event would be unused.

Reaching the connect path at all needed two new fakes. FakeRenderer attaches the
way the real page does — fetch the served page, read back the token and socket
URL the host substituted into it, then open the socket with both subprotocols —
rather than being handed the token, so the part of the handshake that has been
got wrong before stays under test. FakeSsh replaces a factory that would need a
reachable sshd, which DodoSSH.Client.Ssh.Tests already covers against a
container. The suite also never called workspace.Start(), so nothing served the
page and no renderer could have attached.

DllImport rather than the source-generated LibraryImport, which requires
AllowUnsafeBlocks for the whole project. The signature is blittable so there is
no marshalling stub to improve on, and turning unsafe code on across a client
that handles key material to gain nothing is a poor trade.

Correcting an earlier entry: docs/platform-flags.md described this as a
focus-plumbing gap and offered "click inside the terminal first" as the
workaround. Both true, and both stop short of the half that matters — focus
crosses into the WebView readily and never comes back on its own, which is the
same mechanism as the text boxes that mysteriously stopped accepting keystrokes
in the airspace entry above it, not a separate fault.
2026-07-29 14:31:09 +02:00
jaap-jan 5fccd53824 Add the Avalonia app and the xterm renderer, and fix two real bugs
The terminal works end to end. A new integration test drives a real sshd in
a container through a real PTY, the real pump, the real loopback WebSocket
with its token and origin checks, and a ClientWebSocket standing in for the
page: the login banner arrives, typed input round-trips, and `stty size`
reports the 100x30 the session asked for. The only untested link left is
xterm drawing bytes it was handed.

The WebView is de-risked on Windows, which was the plan's largest risk. Not
by assertion: with the app running there is an established TCP connection
from msedgewebview2 to the data plane port, so WebView2 launched, navigated
to the loopback page, executed terminal.js, and completed the WebSocket
handshake against the real token and origin checks. Linux remains unproven
and the package's own release notes now corroborate the concern -- Linux uses
a WPE backend, and it ships a NativeWebDialog described as useful where
embedded WebViews may be unavailable.

Two bugs found by building it, both of which would have shipped:

- ShellStream.Write buffers and needs an explicit Flush. Without one a
  keystroke is accepted, reported as written, and never reaches the remote:
  the terminal displays output perfectly and simply stops responding to
  input. SSH.NET's own WriteLine flushes, which is why the earlier spike
  never hit it. Found by isolating the pump against real SSH and reading
  BytesRead=51 -- banner and prompt through, nothing after.
- The Windows app manifest needs a supportedOS list, or Avalonia's native
  control host fails outright and the terminal never starts.

Also fixed a genuinely flaky test I happened to catch: SyncCursorTests
tampered with the *last* base64url character, whose low bits the decoder
ignores when the input length is not a multiple of three -- so a tampered
cursor sometimes decoded to identical bytes and verified. It failed roughly
one run in thirty, depending on a random key. Now tampers the penultimate
character, which is fully significant at every length; 40 consecutive runs
are clean.

xterm 6.0.0 plus the fit and webgl addons are vendored as UMD bundles rather
than built with npm, so a clean clone needs only the .NET SDK. Provenance
and licences are recorded next to them, along with the UMD global names
terminal.js depends on -- a bundle that switched to ES modules would load
without error and leave Terminal undefined.

The renderer acknowledges output from term.write's completion callback, not
on receipt. Acknowledging early would return flow-control credit for bytes
the screen has not caught up with, which is the one thing the credit window
exists to measure.

TerminalWorkspace moved into DodoSSH.Client.Terminal: it has no Avalonia
dependency, and having it there is what let the end-to-end test exist at all.

404 tests pass, zero warnings on a clean rebuild, format clean.
2026-07-28 22:30:42 +02:00