// walkthrough: error-contract (cross-cutting)
// covers: bullet 4 — forced 5xx response triggers the error toast, no UI
// bleed (no orphan partial, no half-swap).
//
// Uses rod's request hijacking to inject a 500 response for a specific
// known POST without modifying the app. Verifies that
// internal/embeds/static/error-handler.js fires its showErrorToast funnel.
package operatorwalkthroughs_test

import (
	"strings"
	"testing"
	"time"

	"github.com/go-rod/rod"
	"github.com/go-rod/rod/lib/proto"
)

func TestErrorContractWalkthrough(t *testing.T) {
	base := baseURL(t)
	browser := newBrowser(t)
	page := browser.MustPage()

	loginAsOperator(t, page, base, "/operator/entitlement-sets")

	t.Logf("hijacking POST /partials/operator/entitlement-sets → 500")
	router := page.HijackRequests()
	defer router.MustStop()
	router.MustAdd("*/partials/operator/entitlement-sets", func(ctx *rod.Hijack) {
		if string(ctx.Request.Method()) != "POST" {
			ctx.ContinueRequest(&proto.FetchContinueRequest{})
			return
		}
		ctx.Response.SetHeader("Content-Type", "text/html")
		ctx.Response.Payload().ResponseCode = 500
		ctx.Response.SetBody("internal server error")
	})
	go router.Run()

	t.Logf("submit valid entitlement set form → hijacked 500 → expect error toast")
	page.MustElement(`#setName`).MustInput("e2e-error-contract")
	page.MustElement(`#createEntitlementSetForm button[type=submit]`).MustClick()

	// error-handler.js calls showErrorToast() for 5xx; #errorToast.show
	// should appear.
	page.Timeout(10 * time.Second).MustElement(`#errorToast.show`)

	// No UI bleed: the form should still be intact (not half-swapped).
	if _, err := page.Element(`#createEntitlementSetForm`); err != nil {
		t.Errorf("UI bleed: createEntitlementSetForm vanished after 5xx (should be preserved)")
	}

	errText := strings.TrimSpace(page.MustElement(`#errorToast`).MustText())
	if errText == "" {
		t.Errorf("error toast text is empty")
	}
}