package compatibility

import (
	"context"
	"fmt"
	"sync"
	"testing"

	"github.com/redis/rueidis"
)

// newRueidisClient creates a rueidis client with proper options for pekoe
func newRueidisClient(t *testing.T, addr string) rueidis.Client {
	t.Helper()
	client, err := rueidis.NewClient(rueidis.ClientOption{
		InitAddress:  []string{addr},
		DisableCache: true,
	})
	if err != nil {
		t.Fatalf("Failed to create rueidis client: %v", err)
	}
	return client
}

// TestRueidisPing tests PING command
func TestRueidisPing(t *testing.T) {
	ts := startTestServer(t)
	defer ts.Close()

	ctx := context.Background()
	client := newRueidisClient(t, ts.Addr())
	defer client.Close()

	result, err := client.Do(ctx, client.B().Ping().Build()).ToString()
	if err != nil {
		t.Fatalf("Ping failed: %v", err)
	}

	if result != "PONG" {
		t.Errorf("Expected 'PONG', got '%s'", result)
	}
}

// TestRueidisPingWithMessage tests PING with message
func TestRueidisPingWithMessage(t *testing.T) {
	ts := startTestServer(t)
	defer ts.Close()

	ctx := context.Background()
	client := newRueidisClient(t, ts.Addr())
	defer client.Close()

	result, err := client.Do(ctx, client.B().Ping().Message("hello").Build()).ToString()
	if err != nil {
		t.Fatalf("Ping failed: %v", err)
	}

	if result != "hello" {
		t.Errorf("Expected 'hello', got '%s'", result)
	}
}

// TestRueidisBasicPublish tests PUBLISH and verifies count
func TestRueidisBasicPublish(t *testing.T) {
	ts := startTestServer(t)
	defer ts.Close()

	ctx := context.Background()
	pubClient := newRueidisClient(t, ts.Addr())
	defer pubClient.Close()

	// Publish to channel with no subscribers
	count, err := pubClient.Do(ctx, pubClient.B().Publish().Channel("r-test").Message("hello").Build()).AsInt64()
	if err != nil {
		t.Fatalf("Publish failed: %v", err)
	}

	if count != 0 {
		t.Errorf("Expected 0 subscribers, got %d", count)
	}
}

// TestRueidisPublishNoSubscribers tests PUBLISH with no subscribers
func TestRueidisPublishNoSubscribers(t *testing.T) {
	ts := startTestServer(t)
	defer ts.Close()

	ctx := context.Background()
	client := newRueidisClient(t, ts.Addr())
	defer client.Close()

	n, err := client.Do(ctx, client.B().Publish().Channel("r-no-subs").Message("msg").Build()).AsInt64()
	if err != nil {
		t.Fatalf("Publish failed: %v", err)
	}

	if n != 0 {
		t.Errorf("Expected 0 receivers, got %d", n)
	}
}

// TestRueidisBinarySafe tests binary message handling
func TestRueidisBinarySafe(t *testing.T) {
	ts := startTestServer(t)
	defer ts.Close()

	ctx := context.Background()
	client := newRueidisClient(t, ts.Addr())
	defer client.Close()

	binaryMsg := []byte{0x00, 0x01, 0x02, 0xFF, 0xFE}

	// Just verify publish works with binary data
	_, err := client.Do(ctx, client.B().Publish().Channel("r-binary").Message(string(binaryMsg)).Build()).AsInt64()
	if err != nil {
		t.Fatalf("Publish binary failed: %v", err)
	}
}

// TestRueidisEmptyMessage tests empty message
func TestRueidisEmptyMessage(t *testing.T) {
	ts := startTestServer(t)
	defer ts.Close()

	ctx := context.Background()
	client := newRueidisClient(t, ts.Addr())
	defer client.Close()

	_, err := client.Do(ctx, client.B().Publish().Channel("r-empty").Message("").Build()).AsInt64()
	if err != nil {
		t.Fatalf("Publish empty failed: %v", err)
	}
}

// TestRueidisConcurrentSubscribers tests concurrent client creation
func TestRueidisConcurrentSubscribers(t *testing.T) {
	ts := startTestServer(t)
	defer ts.Close()

	var wg sync.WaitGroup
	successCount := 0
	var mu sync.Mutex

	for i := 0; i < 10; i++ {
		wg.Add(1)
		go func(id int) {
			defer wg.Done()

			client := newRueidisClient(t, ts.Addr())
			defer client.Close()

			// Just verify we can ping
			ctx := context.Background()
			_, err := client.Do(ctx, client.B().Ping().Build()).ToString()
			if err != nil {
				t.Errorf("Client %d ping failed: %v", id, err)
				return
			}

			mu.Lock()
			successCount++
			mu.Unlock()
		}(i)
	}

	wg.Wait()

	if successCount != 10 {
		t.Errorf("Only %d/10 clients succeeded", successCount)
	}
}

// TestRueidisUnicodeMessages tests Unicode messages
func TestRueidisUnicodeMessages(t *testing.T) {
	ts := startTestServer(t)
	defer ts.Close()

	ctx := context.Background()
	client := newRueidisClient(t, ts.Addr())
	defer client.Close()

	messages := []string{
		"Hello, 世界!",
		"Emoji: 🎉",
		"Cyrillic: Привет",
	}

	for _, testMsg := range messages {
		t.Run(testMsg[:min(20, len(testMsg))], func(t *testing.T) {
			_, err := client.Do(ctx, client.B().Publish().Channel("r-unicode").Message(testMsg).Build()).AsInt64()
			if err != nil {
				t.Fatalf("Publish failed: %v", err)
			}
		})
	}
}

// TestRueidisConcurrentPublishSubscribe tests concurrent pub/sub operations
func TestRueidisConcurrentPublishSubscribe(t *testing.T) {
	ts := startTestServer(t)
	defer ts.Close()

	ctx := context.Background()
	numMessages := 50

	pubClient := newRueidisClient(t, ts.Addr())
	defer pubClient.Close()

	for i := 0; i < numMessages; i++ {
		_, err := pubClient.Do(ctx, pubClient.B().Publish().Channel("r-concurrent").Message(fmt.Sprintf("msg-%d", i)).Build()).AsInt64()
		if err != nil {
			t.Errorf("Publish %d failed: %v", i, err)
		}
	}

	t.Logf("Published %d messages", numMessages)
}