package asterisk

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

	"github.com/CyCoreSystems/ari/v5"
)

type answerEvents struct {
	ari.Subscription
	events chan ari.Event
}

func (f answerEvents) Events() <-chan ari.Event { return f.events }
func (f answerEvents) Cancel()                  {}

func TestAwaitDialUpRequiresStasisAndPostDialUp(t *testing.T) {
	const id = "execution-1"
	for _, tc := range []struct {
		name   string
		events []ari.Event
		answer bool
	}{
		{"created_not_answered", []ari.Event{&ari.StasisStart{Channel: ari.ChannelData{ID: id}}}, false},
		{"up_without_stasis", []ari.Event{&ari.ChannelStateChange{Channel: ari.ChannelData{ID: id, State: "Up"}}}, false},
		{"wrong_channel", []ari.Event{&ari.StasisStart{Channel: ari.ChannelData{ID: "other"}}, &ari.ChannelStateChange{Channel: ari.ChannelData{ID: "other", State: "Up"}}}, false},
		{"answer", []ari.Event{&ari.StasisStart{Channel: ari.ChannelData{ID: id}}, &ari.ChannelStateChange{Channel: ari.ChannelData{ID: id, State: "Up"}}}, true},
		{"answer_reordered", []ari.Event{&ari.ChannelStateChange{Channel: ari.ChannelData{ID: id, State: "Up"}}, &ari.StasisStart{Channel: ari.ChannelData{ID: id}}}, true},
		{"destroyed_before_answer", []ari.Event{&ari.StasisStart{Channel: ari.ChannelData{ID: id}}, &ari.ChannelDestroyed{Channel: ari.ChannelData{ID: id}}}, false},
	} {
		t.Run(tc.name, func(t *testing.T) {
			ch := make(chan ari.Event, len(tc.events))
			for _, event := range tc.events {
				ch <- event
			}
			ctx, cancel := context.WithTimeout(context.Background(), 10*time.Millisecond)
			defer cancel()
			err := awaitDialUp(ctx, answerEvents{events: ch}, id)
			if (err == nil) != tc.answer {
				t.Fatalf("answer proof mismatch: %v", err)
			}
		})
	}
}

func TestAwaitDialUpFailsClosedOnLostEventsOrCancellation(t *testing.T) {
	ch := make(chan ari.Event)
	close(ch)
	if err := awaitDialUp(context.Background(), answerEvents{events: ch}, "execution-1"); err == nil || !strings.Contains(err.Error(), "closed") {
		t.Fatalf("subscription loss was hidden: %v", err)
	}
	ctx, cancel := context.WithCancel(context.Background())
	cancel()
	if err := awaitDialUp(ctx, answerEvents{events: make(chan ari.Event)}, "execution-1"); !errors.Is(err, context.Canceled) {
		t.Fatalf("cancellation was hidden: %v", err)
	}
}