package xmppsig

import (
	"context"
	"strings"
	"testing"
	"time"

	"dev.narayana.im/narayana/telegabber/calls/signaling"
	"dev.narayana.im/narayana/telegabber/xmpp/jingle"

	"gosrc.io/xmpp/stanza"
)

// cross-side teardown for XMPP-originated calls:
// inbound terminate -> Session observer -> bridge.Terminate -> both halves Terminate

func TestCalleeOnTerminated_SessionTerminate_TearsDownTGCaller(t *testing.T) {
	callee, _, tgSide := newBoundCallee(t)
	callee.OnTerminated(jingle.ReasonSuccess)
	waitUntil(t, "tg-Caller.Terminate", time.Second, tgSide.isTerminated)
	if tgSide.reason() != signaling.ReasonHangup {
		t.Errorf("tg-side reason = %v, want ReasonHangup", tgSide.reason())
	}
}

// inbound JMI <retract> in StateRinging drives the same teardown
func TestCalleeInboundRetract_TearsDownTGCaller(t *testing.T) {
	callee, sess, tgSide := newBoundCallee(t)
	// simulate the post-propose StateRinging by hand
	sess.HandleJMI("alice@xmpp.example/desktop", &jingle.JMIPropose{
		ID:           sess.SID(),
		Descriptions: []jingle.JMIDescription{{Media: "audio"}},
	})
	waitUntil(t, "session in ringing", time.Second, func() bool {
		return sess.State() == jingle.StateRinging
	})

	mgr := callee.a.cfg.Manager
	ret := stanza.NewMessage(stanza.Attrs{
		Type: stanza.MessageTypeChat,
		From: "alice@xmpp.example/desktop",
		To:   "gw.example",
		Id:   "ret-1",
	})
	ret.Extensions = []stanza.MsgExtension{&jingle.JMIRetract{ID: sess.SID()}}
	mgr.HandleMessage(&ret)

	waitUntil(t, "tg-Caller.Terminate", time.Second, tgSide.isTerminated)
	if tgSide.reason() != signaling.ReasonPeerGone {
		t.Errorf("tg-side reason = %v, want ReasonPeerGone", tgSide.reason())
	}
}

// outgoing JMI <ringing>/<proceed> `from` must match propose's `to`,
// otherwise libdino's from.equals_bare(peer_state.jid) silently drops
// the proceed and no session-initiate follows
func TestCallee_RingingProceedFromMatchesProposeTo(t *testing.T) {
	send := &recSender{}
	mgr := &jingle.Manager{LocalJID: "gw.example", Sender: send}
	a := NewAdapter(AdapterConfig{
		Sender: send, LocalJID: "gw.example", Manager: mgr,
		PCFactory: pcFactory(t),
	})

	// realistic XMPP-originated propose
	prop := jingle.IncomingProposal{
		SID:   "incoming-sid-1",
		From:  "alice@xmpp.example/desktop",
		To:    "12345@gw.example",
		Media: []string{"audio"},
	}
	_, sess, err := a.NewCallee(prop)
	if err != nil {
		t.Fatalf("NewCallee: %v", err)
	}
	mgr.Register(sess)

	// Bring the session into StateRinging via the same path production
	// uses, so Ringing/AcceptProposal pass their state guards.
	sess.HandleJMI(prop.From, &jingle.JMIPropose{
		ID:           prop.SID,
		Descriptions: []jingle.JMIDescription{{Media: "audio"}},
	})
	waitUntil(t, "session in ringing", time.Second, func() bool {
		return sess.State() == jingle.StateRinging
	})

	if err := sess.Ringing(context.Background()); err != nil {
		t.Fatalf("Ringing: %v", err)
	}
	if err := sess.AcceptProposal(context.Background()); err != nil {
		t.Fatalf("AcceptProposal: %v", err)
	}

	// every JMI <message>: from's bare must equal propose.To and from must
	// be a full JID (Conversations crashes on bare-JID `with`)
	wantBare := prop.To
	wantFrom := prop.To + "/" + prop.SID
	dontWantFrom := "gw.example"
	var sawRinging, sawProceed bool
	for _, pkt := range send.snapshot() {
		var msg *stanza.Message
		switch m := pkt.(type) {
		case *stanza.Message:
			msg = m
		case stanza.Message:
			msg = &m
		default:
			continue
		}
		if msg.From == dontWantFrom {
			t.Errorf("outbound JMI message from=%q (the bare component domain); want bare=%q with a resource", msg.From, wantBare)
		}
		if msg.From != wantFrom {
			t.Errorf("outbound JMI message from=%q; want %q", msg.From, wantFrom)
		}
		if !strings.Contains(msg.From, "/") {
			t.Errorf("outbound JMI message from=%q is bare; Conversations routes bare-JID updates through a crash-prone proposal-state lambda", msg.From)
		}
		for _, ext := range msg.Extensions {
			switch ext.(type) {
			case *jingle.JMIRinging:
				sawRinging = true
			case *jingle.JMIProceed:
				sawProceed = true
			}
		}
	}
	if !sawRinging {
		t.Error("never observed an outbound <ringing>")
	}
	if !sawProceed {
		t.Error("never observed an outbound <proceed>")
	}
}

// <ringing> must come from Callee.Ringing (driven by tdlib Pending), not
// from Callee.Accept; otherwise back-to-back ringing+proceed produces a
// millisecond ringback window in Dino/anotherim and "discovering devices"
// in Conversations
func TestCalleeAccept_DoesNotEmitRinging(t *testing.T) {
	send := &recSender{}
	mgr := &jingle.Manager{LocalJID: "gw.example", Sender: send}
	a := NewAdapter(AdapterConfig{
		Sender: send, LocalJID: "gw.example", Manager: mgr,
		PCFactory: pcFactory(t),
	})
	prop := jingle.IncomingProposal{
		SID:   "sid-accept-no-ring",
		From:  "alice@xmpp.example/desktop",
		To:    "12345@gw.example",
		Media: []string{"audio"},
	}
	callee, sess, err := a.NewCallee(prop)
	if err != nil {
		t.Fatalf("NewCallee: %v", err)
	}
	mgr.Register(sess)

	sess.HandleJMI(prop.From, &jingle.JMIPropose{
		ID:           prop.SID,
		Descriptions: []jingle.JMIDescription{{Media: "audio"}},
	})
	waitUntil(t, "session in ringing", time.Second, func() bool {
		return sess.State() == jingle.StateRinging
	})

	// Accept without Ringing: <proceed> must appear, <ringing> must not
	callee.Accept()
	waitUntil(t, "proceed emitted", time.Second, func() bool {
		for _, pkt := range send.snapshot() {
			msg, ok := pkt.(*stanza.Message)
			if !ok {
				continue
			}
			for _, ext := range msg.Extensions {
				if _, isProceed := ext.(*jingle.JMIProceed); isProceed {
					return true
				}
			}
		}
		return false
	})

	for _, pkt := range send.snapshot() {
		msg, ok := pkt.(*stanza.Message)
		if !ok {
			continue
		}
		for _, ext := range msg.Extensions {
			if _, isRinging := ext.(*jingle.JMIRinging); isRinging {
				t.Fatalf("Accept emitted <ringing>; <ringing> must come exclusively from Callee.Ringing (split was deliberate, see callee.go)")
			}
		}
	}
}

func newBoundCallee(t *testing.T) (*Callee, *jingle.Session, *recBridgeSide) {
	t.Helper()
	send := &recSender{}
	mgr := &jingle.Manager{LocalJID: "gw.example", Sender: send}
	a := NewAdapter(AdapterConfig{
		Sender: send, LocalJID: "gw.example", Manager: mgr,
		PCFactory: pcFactory(t),
	})
	callee, sess, err := a.NewCallee(jingle.IncomingProposal{
		SID: "incoming-sid-1", From: "alice@xmpp.example/desktop", To: "gw.example", Media: []string{"audio"},
	})
	if err != nil {
		t.Fatalf("NewCallee: %v", err)
	}
	// register so inbound stanzas in integration tests find the session
	mgr.Register(sess)

	tgSide := &recBridgeSide{}
	br := signaling.New(signaling.Config{
		Caller: tgSide, Callee: callee, Timers: noopTimers{},
	})
	callee.Bind(br)
	// bridge.Start moves out of StateIdle so terminate fires for real
	br.Start()
	return callee, sess, tgSide
}