package rabbitmq

import (
	"context"

	"github.com/gogf/gf/v2/encoding/gjson"
	"github.com/gogf/gf/v2/errors/gerror"
	"github.com/gogf/gf/v2/frame/g"
	amqp "github.com/rabbitmq/amqp091-go"
)

// Publisher 消息发布器
type Publisher struct {
	exchange   string
	routingKey string
}

// NewPublisher 创建发布器
func NewPublisher(exchange, routingKey string) *Publisher {
	return &Publisher{
		exchange:   exchange,
		routingKey: routingKey,
	}
}

// Publish 发布消息（使用默认 routing key）
func (p *Publisher) Publish(ctx context.Context, message interface{}) (err error) {
	return p.PublishWithRoutingKey(ctx, p.routingKey, message)
}

// PublishWithRoutingKey 发布消息（指定 routing key）
func (p *Publisher) PublishWithRoutingKey(ctx context.Context, routingKey string, message interface{}) (err error) {
	ch, err := GetChannel()
	if err != nil {
		return err
	}

	// 序列化消息
	body, err := gjson.Encode(message)
	if err != nil {
		return gerror.Newf("消息序列化失败: %v", err)
	}

	// 发布消息
	err = ch.PublishWithContext(
		ctx,
		p.exchange, // exchange
		routingKey, // routing key
		false,      // mandatory
		false,      // immediate
		amqp.Publishing{
			DeliveryMode: amqp.Persistent, // 持久化
			ContentType:  "application/json",
			Body:         body,
		},
	)

	if err != nil {
		g.Log().Errorf(ctx, "发布消息失败: exchange=%s, routingKey=%s, err=%v",
			p.exchange, routingKey, err)
		return err
	}

	g.Log().Debugf(ctx, "消息发布成功: exchange=%s, routingKey=%s",
		p.exchange, routingKey)

	return
}

// PublishDelayed 发布延时消息
// delaySeconds: 延时秒数
func (p *Publisher) PublishDelayed(ctx context.Context, message interface{}, delaySeconds int) (err error) {
	ch, err := GetChannel()
	if err != nil {
		return err
	}

	// 序列化消息
	body, err := gjson.Encode(message)
	if err != nil {
		return gerror.Newf("消息序列化失败: %v", err)
	}

	// 发布延时消息（需要 rabbitmq_delayed_message_exchange 插件）
	err = ch.PublishWithContext(
		ctx,
		p.exchange,   // exchange（必须是 x-delayed-message 类型）
		p.routingKey, // routing key
		false,        // mandatory
		false,        // immediate
		amqp.Publishing{
			DeliveryMode: amqp.Persistent,
			ContentType:  "application/json",
			Body:         body,
			Headers: amqp.Table{
				"x-delay": delaySeconds * 1000, // 延时（毫秒）
			},
		},
	)

	if err != nil {
		g.Log().Errorf(ctx, "发布延时消息失败: exchange=%s, routingKey=%s, delay=%ds, err=%v",
			p.exchange, p.routingKey, delaySeconds, err)
		return err
	}

	g.Log().Debugf(ctx, "延时消息发布成功: exchange=%s, routingKey=%s, delay=%ds",
		p.exchange, p.routingKey, delaySeconds)

	return
}

// PublishBatch 批量发布消息
func (p *Publisher) PublishBatch(ctx context.Context, messages []interface{}) (err error) {
	if len(messages) == 0 {
		return
	}

	ch, err := GetChannel()
	if err != nil {
		return err
	}

	for i, message := range messages {
		body, err := gjson.Encode(message)
		if err != nil {
			g.Log().Errorf(ctx, "消息 %d 序列化失败: %v", i, err)
			continue
		}

		err = ch.PublishWithContext(
			ctx,
			p.exchange,
			p.routingKey,
			false,
			false,
			amqp.Publishing{
				DeliveryMode: amqp.Persistent,
				ContentType:  "application/json",
				Body:         body,
			},
		)

		if err != nil {
			g.Log().Errorf(ctx, "消息 %d 发布失败: %v", i, err)
			continue
		}
	}

	g.Log().Infof(ctx, "批量发布完成: 共 %d 条消息", len(messages))
	return
}