go-html/cmd/wasm/main.go
Claude dcd55a434c
feat(wasm): add registerComponents export for WC codegen
Exposes gohtml.registerComponents(slotsJSON) to browser context.
Pure-Go buildComponentJS is testable without WASM; WASM glue uses
Function constructor for browser-side execution.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
2026-02-17 20:50:50 +00:00

78 lines
2.1 KiB
Go

//go:build js && wasm
package main
import (
"syscall/js"
html "forge.lthn.ai/core/go-html"
)
// renderToString builds an HLCRF layout from JS arguments and returns HTML.
// Slot content is injected via Raw() — the caller is responsible for sanitisation.
// This is intentional: the WASM module is a rendering engine for trusted content
// produced server-side or by the application's own templates.
func renderToString(_ js.Value, args []js.Value) any {
if len(args) < 1 {
return ""
}
variant := args[0].String()
ctx := html.NewContext()
if len(args) >= 2 {
ctx.Locale = args[1].String()
}
layout := html.NewLayout(variant)
if len(args) >= 3 && args[2].Type() == js.TypeObject {
slots := args[2]
for _, slot := range []string{"H", "L", "C", "R", "F"} {
content := slots.Get(slot)
if content.Type() == js.TypeString && content.String() != "" {
switch slot {
case "H":
layout.H(html.Raw(content.String()))
case "L":
layout.L(html.Raw(content.String()))
case "C":
layout.C(html.Raw(content.String()))
case "R":
layout.R(html.Raw(content.String()))
case "F":
layout.F(html.Raw(content.String()))
}
}
}
}
return layout.Render(ctx)
}
// registerComponentsJS wraps buildComponentJS for the WASM→JS bridge.
// Takes a JSON string of slot assignments, generates the WC bundle,
// and executes it in the browser via the Function constructor.
func registerComponentsJS(_ js.Value, args []js.Value) any {
if len(args) < 1 {
return js.ValueOf("error: slotsJSON argument required")
}
jsCode, err := buildComponentJS(args[0].String())
if err != nil {
return js.ValueOf("error: " + err.Error())
}
// Execute the generated WC definitions in the browser context.
// Uses the standard Function constructor — the normal Go WASM→JS pattern.
fn := js.Global().Call("Function", jsCode)
fn.Invoke()
return js.ValueOf(jsCode)
}
func main() {
js.Global().Set("gohtml", js.ValueOf(map[string]any{
"renderToString": js.FuncOf(renderToString),
"registerComponents": js.FuncOf(registerComponentsJS),
}))
select {}
}