package stateobjects

import (
	"bytes"
	"strings"
	"testing"
)

// ADR 0666 §16: a reply or an event over the per-message limit carries the name of an object, and the receiver reads it
// back whole; one that fits is sent as it is.
func TestABodyOverTheMessageLimitIsSentAsAReference(t *testing.T) {
	m := newMemory()
	s := Sender{Objects: memObjects{m}, Store: "m_sent-objects"}
	fetch := ProcessFetch(memObjects{m})
	for _, label := range []string{"reply.list", "event.done"} {
		body := []byte(`{"text":"` + strings.Repeat("y", 3<<20) + `"}`)
		sent, err := s.Send(label, body)
		if err != nil || len(sent) > MessageLimit {
			t.Fatalf("%s: sent %d bytes, %v", label, len(sent), err)
		}
		if _, isRef := ReadRef(sent); !isRef {
			t.Fatalf("%s: a 3 MiB body was sent whole", label)
		}
		got, err := Receive(sent, fetch)
		if err != nil || !bytes.Equal(got, body) {
			t.Fatalf("%s: received %d bytes, %v", label, len(got), err)
		}
	}
	small := []byte(`{"a":1}`)
	if sent, err := s.Send("x", small); err != nil || !bytes.Equal(sent, small) {
		t.Fatalf("a small body: %s, %v", sent, err)
	}
	if got, err := Receive(small, fetch); err != nil || !bytes.Equal(got, small) {
		t.Fatalf("receive a small body: %s, %v", got, err)
	}
	// an object that is not the one the reference names is refused
	sent, _ := s.Send("reply.again", bytes.Repeat([]byte("z"), 2<<20))
	ref, _ := ReadRef(sent)
	m.objects[ref.Object] = []byte("tampered")
	if _, err := Receive(sent, fetch); err == nil {
		t.Fatal("a tampered object was accepted")
	}
	// a bundle's store takes at most what one runtime message carries
	bundle := Sender{Objects: BundleObjects{}, Store: "m_sent-objects"}
	if _, err := bundle.Send("reply.huge", make([]byte, BundleObjectMost+1)); err == nil {
		t.Fatal("a bundle sent a body its runtime cannot carry")
	}
}

// A bundle reads a sent object through the runtime's sent-get.
func TestABundleReadsASentObjectThroughTheRuntime(t *testing.T) {
	m := newMemory()
	body := []byte(`{"text":"` + strings.Repeat("y", 3<<20) + `"}`)
	sent, err := Sender{Objects: memObjects{m}, Store: "m_sent-objects"}.Send("reply.list", body)
	if err != nil {
		t.Fatal(err)
	}
	out := runtimeOf(t, m, func() (any, error) {
		got, err := Receive(sent, BundleFetch)
		if err != nil || !bytes.Equal(got, body) {
			t.Errorf("received %d bytes, %v", len(got), err)
		}
		return "done", nil
	})
	if !strings.Contains(out.(string), "done") {
		t.Fatalf("the bundle answered %v", out)
	}
}