package buildstep

import "strings"

// LauncherSuffix is what a TypeScript entrypoint's launcher is called beside it: index.js is started as
// index.serve.mjs (novox/hq ADR 0193), an ES module by its own extension whatever the bundle's package.json says.
const LauncherSuffix = ".serve.mjs"

// Launchers are the launchers a bundle's build writes, by entrypoint, relative to the bundle's root: for TypeScript
// every entrypoint `x.js` is started by `x.serve.mjs` beside it; an entrypoint that is not JavaScript and every other
// language, whose build is already executable, get none. The one rule mesh-build-node, build-agent and the controller
// share (R4e), so the name a build writes is the name a reader expects.
func Launchers(language string, entrypoints []string) map[string]string {
	out := map[string]string{}
	if language != "typescript" {
		return out
	}
	for _, entry := range entrypoints {
		if strings.HasSuffix(entry, ".js") {
			out[entry] = strings.TrimSuffix(entry, ".js") + LauncherSuffix
		}
	}
	return out
}