refactor folder structure

go/wasmruntime/rsc/client_wasm.go

@@ -0,0 +1,93 @@
+//go:build js && wasm
+
+package rsc
+
+import (
+	"bytes"
+	"encoding/gob"
+	"syscall/js"
+
+	"kjol/wasmruntime/vdom"
+)
+
+// Mount connects to a server component by name and returns a render function.
+// The generated client stub for a //gowasm:server component just calls this, so
+// the call site is identical to a client component. It POSTs {name, state,
+// event} to /rsc and swaps (reconciles) the returned render into the DOM. State
+// is opaque and round-trips through the client — the server keeps nothing.
+func Mount(name string) func() *vdom.VNode {
+	tree := vdom.NewSignal[*vdom.VNode](nil)
+	var state [][]byte
+	var post func(kind string, nodeID int, event, value string)
+
+	var convert func(*SNode) *vdom.VNode
+	convert = func(sn *SNode) *vdom.VNode {
+		if sn == nil {
+			return nil
+		}
+		if sn.Tag == "" {
+			return vdom.Text(sn.Text)
+		}
+		mods := make([]vdom.Mod, 0, len(sn.Attrs)+len(sn.Events)+len(sn.Kids)+1)
+		for k, v := range sn.Attrs {
+			mods = append(mods, vdom.Attr(k, v))
+		}
+		if sn.HTML != "" {
+			mods = append(mods, vdom.Raw(sn.HTML))
+		}
+		for _, ev := range sn.Events {
+			event, id := ev, sn.ID
+			mods = append(mods, vdom.OnEvent(ev, func(e vdom.Event) { post("event", id, event, e.Value()) }))
+		}
+		for _, k := range sn.Kids {
+			if c := convert(k); c != nil {
+				mods = append(mods, c)
+			}
+		}
+		return vdom.El(sn.Tag, mods...)
+	}
+
+	onArr := js.FuncOf(func(this js.Value, args []js.Value) any {
+		arr := js.Global().Get("Uint8Array").New(args[0])
+		b := make([]byte, arr.Get("length").Int())
+		js.CopyBytesToGo(b, arr)
+		var resp Response
+		if gob.NewDecoder(bytes.NewReader(b)).Decode(&resp) == nil {
+			state = resp.State
+			tree.Set(convert(resp.Tree)) // re-render -> reconcile into the DOM
+		}
+		return nil
+	})
+	onResp := js.FuncOf(func(this js.Value, args []js.Value) any {
+		args[0].Call("arrayBuffer").Call("then", onArr)
+		return nil
+	})
+
+	loc := js.Global().Get("location")
+	url := loc.Get("protocol").String() + "//" + loc.Get("host").String() + "/rsc"
+
+	post = func(kind string, nodeID int, event, value string) {
+		var buf bytes.Buffer
+		if gob.NewEncoder(&buf).Encode(Request{Kind: kind, Name: name, State: state, NodeID: nodeID, Event: event, Value: value}) != nil {
+			return
+		}
+		body := js.Global().Get("Uint8Array").New(buf.Len())
+		js.CopyBytesToJS(body, buf.Bytes())
+		opts := js.Global().Get("Object").New()
+		opts.Set("method", "POST")
+		opts.Set("body", body)
+		js.Global().Call("fetch", url, opts).Call("then", onResp)
+	}
+
+	started := false
+	return func() *vdom.VNode {
+		if !started {
+			started = true
+			post("mount", 0, "", "")
+		}
+		if t := tree.Get(); t != nil {
+			return t
+		}
+		return vdom.Div(vdom.Attr("class", "text-muted"), vdom.Text("loading server component…"))
+	}
+}