Share the base++zim++trailer assembly behind a small helper, then add two bundle
builders on top: BuildApp writes a macOS .app (Info.plist, the viewer under
Contents/MacOS, an .icns in Resources), and BuildAppDir writes an AppImage-style
.AppDir (AppRun, a Terminal=false .desktop launcher, a PNG icon). Both keep the
trailer at the tail so Embedded still finds the archive at runtime.
A pure-Go .icns writer (PNG-embedded entries from 16 to 1024) and a finder that
digs the site's favicon out of a cloned mirror, preferring a large apple-touch
icon and unwrapping a PNG-based .ico. These feed the bundle icon for the upcoming
app formats. Adds golang.org/x/image for high-quality resampling.
Packing with --base pointed at a kage built for another OS used to guess the
target from the file name: a base ending in .exe meant Windows, anything else
meant the host. That misfired in both directions. A Windows base without the
.exe suffix produced a viewer with no extension that will not run on Windows,
and an --out name that dropped .exe made the run hint print a macOS quarantine
note for a Windows file.
Sniff the base's executable header (ELF, PE, Mach-O) instead, so the target OS
comes from the bytes rather than the name. A Windows viewer now always gets a
.exe suffix, and the run hint names the real target and only mentions Gatekeeper
for actual macOS viewers.
errcheck flagged six naked defer Close() calls in the pack code and its
tests. Wrap them in the same defer func() { _ = x.Close() }() form the rest
of the tree already uses.
A packed binary opened the system browser, so it felt like a tab, not
an app. Build with -tags webview (cgo) and the viewer instead opens the
site in its own window backed by the OS WebView: WKWebView on macOS,
WebView2 on Windows, WebKitGTK on Linux.
The viewer package picks an implementation at build time. The default
file opens the browser and keeps the build pure Go, so CGO_ENABLED=0 and
the release pipeline are untouched. The webview file links the platform
WebView and runs its event loop on the main goroutine, which main now
pins with LockOSThread before anything else, since macOS requires UI on
the initial thread. Both kage open and the embedded viewer serve over
HTTP in a goroutine and hand the URL to the viewer, then tear the server
down when the window closes or Ctrl-C cancels.
The window title comes from the archive's M/Title. OpenInBrowser moves
out of pack into the viewer package, its only caller.
BuildZIM walks a cloned host directory, turns every file into a content
entry with a MIME inferred from its extension, picks a main page, and adds
the standard metadata plus a mainPage redirect. state.json is skipped.
BuildBinary appends the archive to a copy of kage behind a KAGEPCK1 trailer,
and Embedded detects that trailer at startup so the binary serves itself.
Handler maps / to the main page and /path to a content entry, the same
handler the embedded viewer uses.
Duc-Tam Nguyen