package rabbit

import (
	"errors"
	"log"
	"time"
)

type Publisher interface {
	Start(chanLen uint) <-chan []byte
}

type pubHandler struct {
	client *Client
}

func (p *pubHandler) Start(chanLen uint) <-chan []byte {
	ch := make(chan []byte, chanLen)
	go func() {
		for {
			select {
			case msg := <-ch:
				if err := p.push(msg); err != nil {
					log.Printf("Error publishing message: %s", err)
				}
			}
		}
	}()
	return ch
}

func (p *pubHandler) push(data []byte) error {
	p.client.mutex.Lock()
	if !p.client.isReady {
		p.client.mutex.Unlock()
		return errors.New("failed to push: not connected")
	}
	p.client.mutex.Unlock()
	for {
		err := p.client.unsafePush(data)
		if err != nil {
			p.client.logger.Println("Push failed. Retrying...")
			select {
			case <-p.client.done:
				return errShutdown
			case <-time.After(p.client.opts.resendDelay):
			}
			continue
		}
		confirm := <-p.client.notifyConfirm
		if confirm.Ack {
			p.client.logger.Printf("Push confirmed [%d]!", confirm.DeliveryTag)
			return nil
		}
	}
}