package tracker

import (
	"fmt"
	"sync"
	"testing"
)

func TestTrackerMapsMessageSequenceAndGatewayIDs(t *testing.T) {
	tr := New()

	submit := tr.TrackSubmit("msg-1", 1001)
	if submit.MessageID != "msg-1" || submit.SequenceID != 1001 {
		t.Fatalf("unexpected submit mapping: %+v", submit)
	}

	resp, err := tr.TrackSubmitResp(1001, "gw-1")
	if err != nil {
		t.Fatalf("track submit resp: %v", err)
	}
	if resp.GatewayMessageID != "gw-1" {
		t.Fatalf("unexpected gateway message id: %+v", resp)
	}

	byGateway, err := tr.ByGatewayMessageID("gw-1")
	if err != nil {
		t.Fatalf("lookup by gateway id: %v", err)
	}
	if byGateway.MessageID != "msg-1" || byGateway.SequenceID != 1001 {
		t.Fatalf("unexpected gateway lookup: %+v", byGateway)
	}
}

func TestTrackerRejectsUnknownSubmitResp(t *testing.T) {
	tr := New()

	if _, err := tr.TrackSubmitResp(404, "gw-missing"); err == nil {
		t.Fatal("expected missing mapping error")
	}
}

func TestTrackerKeepsConcurrentSequenceAndGatewayMappingsSeparate(t *testing.T) {
	tr := New()
	var wg sync.WaitGroup

	for i := 0; i < 100; i++ {
		wg.Add(1)
		go func(i int) {
			defer wg.Done()
			messageID := fmt.Sprintf("msg-%03d", i)
			gatewayID := fmt.Sprintf("gw-%03d", i)
			sequenceID := uint32(2000 + i)

			tr.TrackSubmit(messageID, sequenceID)
			mapping, err := tr.TrackSubmitResp(sequenceID, gatewayID)
			if err != nil {
				t.Errorf("track submit resp for %s: %v", messageID, err)
				return
			}
			if mapping.MessageID != messageID || mapping.SequenceID != sequenceID || mapping.GatewayMessageID != gatewayID {
				t.Errorf("unexpected mapping: %+v", mapping)
			}
		}(i)
	}
	wg.Wait()

	for i := 0; i < 100; i++ {
		messageID := fmt.Sprintf("msg-%03d", i)
		gatewayID := fmt.Sprintf("gw-%03d", i)
		sequenceID := uint32(2000 + i)

		byGateway, err := tr.ByGatewayMessageID(gatewayID)
		if err != nil {
			t.Fatalf("lookup gateway %s: %v", gatewayID, err)
		}
		if byGateway.MessageID != messageID || byGateway.SequenceID != sequenceID {
			t.Fatalf("gateway lookup crossed mappings: %+v", byGateway)
		}

		byMessage, err := tr.ByMessageID(messageID)
		if err != nil {
			t.Fatalf("lookup message %s: %v", messageID, err)
		}
		if byMessage.GatewayMessageID != gatewayID || byMessage.SequenceID != sequenceID {
			t.Fatalf("message lookup crossed mappings: %+v", byMessage)
		}
	}
}