// Package dispatch exposes one helper for PRG code: a dynamic
// "call this function by name" hook that pairs with fnode's auto-
// renamed Main symbols. Lets the bridge dispatcher route an HTTP
// path to the right Main without needing a hard-coded `DO CASE`.
//
// PRG surface
//
//	cErr := FNODE_CALL(cFuncName)  -> "" on success, error text on failure
//
// The called function runs on the same Thread; output is left in the
// bridge_capi per-thread output buffer (use _OUT_GET to read it).
// Return values from the called function are discarded — call the
// generated symbol directly when you need its return value.
package dispatch

import (
	"strings"

	"five/hbrt"
)

func init() {
	hbrt.HB_FUNC("FNODE_CALL", fnodeCall)
}

func fnodeCall(ctx *hbrt.HBContext) {
	if ctx.PCount() < 1 || !ctx.IsChar(1) {
		ctx.RetC("FNODE_CALL: function name required")
		return
	}
	name := strings.ToUpper(ctx.ParC(1))
	sym := ctx.T.VM().FindSymbol(name)
	if sym == nil {
		ctx.RetC("function not found: " + ctx.ParC(1))
		return
	}
	ctx.T.PushSymbol(sym)
	ctx.T.PushNil() // self placeholder
	ctx.T.Function(0)
	_ = ctx.T.Pop2() // discard return value
	ctx.RetC("")
}