// 验证 Pulsar 消息的简单脚本
// 使用方法: go run scripts/verify_pulsar_messages.go

package main

import (
	"context"
	"fmt"
	"log"
	"time"

	"github.com/apache/pulsar-client-go/pulsar"
)

const (
	pulsarURL   = "pulsar://localhost:6650"
	topic       = "persistent://public/default/operation"
	timeout     = 10 * time.Second
)

func main() {
	fmt.Println("🔍 Pulsar Message Verification Tool")
	fmt.Println("=====================================")
	fmt.Printf("Pulsar URL: %s\n", pulsarURL)
	fmt.Printf("Topic: %s\n", topic)
	fmt.Println()

	// 创建 Pulsar 客户端
	client, err := pulsar.NewClient(pulsar.ClientOptions{
		URL: pulsarURL,
	})
	if err != nil {
		log.Fatalf("❌ Failed to create Pulsar client: %v", err)
	}
	defer client.Close()
	fmt.Println("✅ Connected to Pulsar")

	// 创建消费者（使用唯一的 subscription）
	subName := fmt.Sprintf("verify-sub-%d", time.Now().Unix())
	consumer, err := client.Subscribe(pulsar.ConsumerOptions{
		Topic:            topic,
		SubscriptionName: subName,
		Type:             pulsar.Shared,
		// 从最早的未确认消息开始读取
		SubscriptionInitialPosition: pulsar.SubscriptionPositionEarliest,
	})
	if err != nil {
		log.Fatalf("❌ Failed to create consumer: %v", err)
	}
	defer consumer.Close()
	fmt.Printf("✅ Consumer created: %s\n\n", subName)

	// 接收消息
	fmt.Println("📩 Listening for messages (timeout: 10s)...")
	fmt.Println("----------------------------------------")

	ctx, cancel := context.WithTimeout(context.Background(), timeout)
	defer cancel()

	messageCount := 0
	for {
		msg, err := consumer.Receive(ctx)
		if err != nil {
			if ctx.Err() == context.DeadlineExceeded {
				break
			}
			log.Printf("⚠️  Error receiving message: %v", err)
			continue
		}

		messageCount++
		fmt.Printf("\n📨 Message #%d:\n", messageCount)
		fmt.Printf("  Key: %s\n", msg.Key())
		fmt.Printf("  Payload Size: %d bytes\n", len(msg.Payload()))
		fmt.Printf("  Publish Time: %v\n", msg.PublishTime())
		fmt.Printf("  Topic: %s\n", msg.Topic())
		fmt.Printf("  Message ID: %v\n", msg.ID())

		// 确认消息
		consumer.Ack(msg)

		// 最多显示 10 条消息
		if messageCount >= 10 {
			fmt.Println("\n⚠️  Reached 10 messages limit, stopping...")
			break
		}
	}

	fmt.Println("\n========================================")
	if messageCount == 0 {
		fmt.Println("❌ No messages found in Pulsar")
		fmt.Println("\nPossible reasons:")
		fmt.Println("  1. No operations have been published yet")
		fmt.Println("  2. All messages have been consumed by other consumers")
		fmt.Println("  3. Wrong topic name")
		fmt.Println("\nTo test, run the E2E test:")
		fmt.Println("  go test ./api/persistence -v -run TestE2E_DBAndTrustlog_WithPulsarConsumer")
	} else {
		fmt.Printf("✅ Found %d messages in Pulsar\n", messageCount)
	}
	fmt.Println("========================================")
}