194 lines
7.1 KiB
Go
194 lines
7.1 KiB
Go
// Package app holds the application's pages and components as standalone
|
||
// functions (no central App struct). It is platform-neutral, so the SAME code
|
||
// renders on the server (SSR) and hydrates on the client.
|
||
//
|
||
// Directives (processed by cmd/wasmgen at build time):
|
||
//
|
||
// //gowasm:page <path> [static] [layout=<name>]
|
||
// marks a page factory as a route. `static`
|
||
// pre-renders it on the server (SSR);
|
||
// `layout=<name>` wraps it in a //gowasm:layout.
|
||
// //gowasm:layout <name> marks a func(Deps, *VNode) *VNode as a named
|
||
// layout that wraps a page's content.
|
||
// //gowasm:server (see server_counter.go) marks a component
|
||
// that runs on the server; the generated
|
||
// client stub makes calling it identical to
|
||
// calling any other component.
|
||
//
|
||
// The Routes() map, StaticPaths set, and RouteLayout/LayoutFor dispatch are all
|
||
// generated from these directives.
|
||
package app
|
||
|
||
//go:generate go run kjol/cmd/wasmgen .
|
||
|
||
import (
|
||
"strconv"
|
||
|
||
. "kjol/vdom"
|
||
)
|
||
|
||
// Deps are the client-only capabilities, injected so the pages stay neutral.
|
||
type Deps struct {
|
||
Path func() string
|
||
Navigate func(string)
|
||
}
|
||
|
||
func itoa(n int) string { return strconv.Itoa(n) }
|
||
|
||
// Layout wraps a page's rendered content with shared chrome (nav, footer, …).
|
||
// Layouts are declared with //gowasm:layout and selected per route via a page's
|
||
// `layout=` directive; the generated LayoutFor dispatches by name.
|
||
type Layout func(d Deps, content *VNode) *VNode
|
||
|
||
// Shell renders the current route's page inside its declared layout. `routes` is
|
||
// the generated route table; `d.Path()` selects both the page and its layout.
|
||
func Shell(d Deps, routes map[string]func() *VNode) *VNode {
|
||
path := d.Path()
|
||
var content *VNode
|
||
if page := routes[path]; page != nil {
|
||
content = page()
|
||
} else {
|
||
content = notFound(path)
|
||
}
|
||
return LayoutFor(d, path, content)
|
||
}
|
||
|
||
func notFound(path string) *VNode {
|
||
return Div(
|
||
H2(Attr("class", "h4 mb-3"), Text("Page not found")),
|
||
P(Attr("class", "text-secondary"), Text("No route matches "+path+".")),
|
||
)
|
||
}
|
||
|
||
// --- layouts (selected per route via `layout=` in //gowasm:page) ---------
|
||
|
||
// PublicLayout is the chrome for public/marketing pages: a light navbar with a
|
||
// call-to-action into the app, and a footer. The func(Deps, *VNode) *VNode shape
|
||
// is what //gowasm:layout expects.
|
||
//
|
||
//gowasm:layout public
|
||
func PublicLayout(d Deps, content *VNode) *VNode {
|
||
return Div(
|
||
Nav(Attr("class", "navbar navbar-expand bg-light border-bottom mb-4"),
|
||
Div(Attr("class", "container"),
|
||
A(Attr("class", "navbar-brand fw-bold"), Attr("href", "/"), navigate(d, "/"), Text("gowasm")),
|
||
Ul(Attr("class", "navbar-nav ms-auto align-items-center"),
|
||
navItem(d, "/", "Home"),
|
||
navItem(d, "/about", "About"),
|
||
Li(Attr("class", "nav-item ms-2"),
|
||
A(Attr("class", "btn btn-sm btn-primary"), Attr("href", "/chart"),
|
||
navigate(d, "/chart"), Text("Open app →"))),
|
||
))),
|
||
Main(Attr("class", "container"),
|
||
content,
|
||
Footer(Attr("class", "text-secondary small border-top mt-5 pt-3"),
|
||
Text("gowasm public site — a tiny Blazor-like engine in Go.")),
|
||
),
|
||
)
|
||
}
|
||
|
||
// AppLayout is the chrome for the application itself: a dark app navbar listing
|
||
// the app's sections, plus a link back to the public site.
|
||
//
|
||
//gowasm:layout app
|
||
func AppLayout(d Deps, content *VNode) *VNode {
|
||
return Div(
|
||
Nav(Attr("class", "navbar navbar-expand navbar-dark bg-dark mb-4"),
|
||
Div(Attr("class", "container"),
|
||
A(Attr("class", "navbar-brand fw-bold"), Attr("href", "/chart"), navigate(d, "/chart"), Text("gowasm · app")),
|
||
Ul(Attr("class", "navbar-nav me-auto"),
|
||
navItem(d, "/chart", "Chart"),
|
||
navItem(d, "/server", "Server")),
|
||
Ul(Attr("class", "navbar-nav"),
|
||
navItem(d, "/", "Home")),
|
||
)),
|
||
Main(Attr("class", "container"), content),
|
||
)
|
||
}
|
||
|
||
// navItem is a nav link that carries an active state on the current route.
|
||
func navItem(d Deps, path, label string) *VNode {
|
||
cls := "nav-link"
|
||
if d.Path() == path {
|
||
cls += " active"
|
||
}
|
||
return Li(Attr("class", "nav-item"),
|
||
A(Attr("class", cls), Attr("href", path), navigate(d, path), Text(label)))
|
||
}
|
||
|
||
// navigate intercepts a link click for client-side SPA navigation. On the server
|
||
// Navigate is nil, so the anchor falls back to a normal navigation.
|
||
func navigate(d Deps, path string) Mod {
|
||
return OnEvent(EVENT_CLICK, func(e Event) {
|
||
if d.Navigate != nil {
|
||
e.PreventDefault()
|
||
d.Navigate(path)
|
||
}
|
||
})
|
||
}
|
||
|
||
// Counter is a presentational client component; state is owned by the caller.
|
||
func Counter(label string, count *Signal[int]) *VNode {
|
||
return Div(Attr("class", "counter card mb-2"),
|
||
Div(Attr("class", "card-body py-2 d-flex align-items-center"),
|
||
Span(Attr("class", "me-2 fw-semibold"), Text(label+": ")),
|
||
Strong(Attr("class", "badge text-bg-primary me-2"), Text(itoa(count.Get()))),
|
||
Div(Attr("class", "btn-group btn-group-sm ms-auto"),
|
||
Button(Attr("class", "btn btn-outline-secondary"),
|
||
On(EVENT_CLICK, func() { count.Update(func(v int) int { return v - 1 }) }), Text("−")),
|
||
Button(Attr("class", "btn btn-outline-primary"),
|
||
On(EVENT_CLICK, func() { count.Update(func(v int) int { return v + 1 }) }), Text("+")),
|
||
)))
|
||
}
|
||
|
||
//gowasm:page / static layout=public
|
||
func HomePage(d Deps) func() *VNode {
|
||
a := NewSignal(0)
|
||
b := NewSignal(0)
|
||
return func() *VNode {
|
||
return Div(
|
||
H2(Attr("class", "h4 mb-3"), Text("Home — component composition")),
|
||
P(Attr("class", "text-secondary"), Text("Two counters; the total is derived across them. Server-rendered, then hydrated.")),
|
||
Counter("Apples", a),
|
||
Counter("Bananas", b),
|
||
Div(Attr("class", "alert alert-info d-flex justify-content-between align-items-center mt-3"),
|
||
Span(Text("Combined total: ")),
|
||
Strong(Attr("class", "fs-5"), Text(itoa(a.Get()+b.Get())))),
|
||
)
|
||
}
|
||
}
|
||
|
||
//gowasm:page /about static layout=public
|
||
func AboutPage(d Deps) func() *VNode {
|
||
return func() *VNode {
|
||
return Div(
|
||
H2(Attr("class", "h4 mb-3"), Text("About")),
|
||
P(Attr("class", "lead"),
|
||
Text("Components are standalone functions; calling a server component looks "+
|
||
"identical to calling a client one — the //gowasm:server directive and the "+
|
||
"build-time codegen wire up the round-trip. Static routes are SSR'd; the rest "+
|
||
"render on the client.")),
|
||
)
|
||
}
|
||
}
|
||
|
||
//gowasm:page /server layout=app
|
||
func ServerPage(d Deps) func() *VNode {
|
||
// ServerCounter is a server component — but calling it is just like calling
|
||
// any component. On the client this resolves to a generated stub that mounts
|
||
// it over /rsc; on the server it's the real function. (Not `static`: the
|
||
// client renders the stub, which round-trips, so there's nothing stable to
|
||
// pre-render + hydrate.)
|
||
counter := ServerCounter()
|
||
return func() *VNode {
|
||
return Div(
|
||
H2(Attr("class", "h4 mb-3"), Text("Server component")),
|
||
P(Attr("class", "text-secondary"),
|
||
Text("This counter runs on the server. Its state lives there; clicks round-trip "+
|
||
"and the returned render merges into the DOM. The call site is identical to a "+
|
||
"client component.")),
|
||
counter(),
|
||
)
|
||
}
|
||
}
|