Initial push

internal/webui/embed.go

@@ -0,0 +1,35 @@
+// Package webui embeds the built web application into the binary so the tool
+// ships as a single file with no runtime assets to install.
+package webui
+
+import (
+	"embed"
+	"io/fs"
+)
+
+//go:embed all:dist
+var dist embed.FS
+
+// FS returns the built web app rooted at its index.html, or nil when the
+// frontend has not been built into this binary.
+func FS() fs.FS {
+	sub, err := fs.Sub(dist, "dist")
+	if err != nil {
+		return nil
+	}
+	if _, err := fs.Stat(sub, "index.html"); err != nil {
+		return nil
+	}
+	return sub
+}
+
+// Built reports whether a real UI is embedded, as opposed to the placeholder
+// that keeps the package compiling before the frontend is built.
+func Built() bool {
+	sub := FS()
+	if sub == nil {
+		return false
+	}
+	_, err := fs.Stat(sub, "assets")
+	return err == nil
+}