package emq5

import (
	"strings"
)

type Engine struct {
	*Options
	Topic      string
	TopicLen   int
	Wildcard   bool
	Shared     bool
	ShareGroup string
	Qos        int
}

func (o *Options) NewEngine(topic string, wildcard bool, qos int) (eng *Engine) {
	eng = &Engine{
		Options:  o,
		Topic:    topic,
		Wildcard: wildcard,
		Qos:      qos,
	}
	eng.checkTopic()
	o.Engine = append(o.Engine, eng)
	return
}

func (o *Options) NewSingleEngine(topic string, wildcard bool, qos int, handler Handler) {
	eng := &Engine{
		Options: o,
		Topic:   topic,
		Qos:     qos,
	}
	eng.checkTopic()
	o.Engine = append(o.Engine, eng)
	eng.Register("", handler)
	return
}

func (e *Engine) checkTopic() {
	if e.Topic[0] == '/' {
		e.Logger.Error("topic禁止以'/'符号开头")
		return
	}
	if e.Topic[len(e.Topic)-1] == '/' {
		e.Logger.Error("topic禁止以'/'符号开头")
		return
	}
	e.TopicLen = len(strings.Split(e.Topic, "/"))
}

// Register 注册方法到前缀树
func (e *Engine) Register(url string, handler Handler) {
	e.checkUrl(url)
	topic := e.Topic + url
	if handler == nil {
		e.Logger.Error("此topic未绑定方法")
		return
	}
	path := e.splitUrl(topic)
	for i, s := range path {
		if s == "" {
			path = append(path[:i], path[i+1:]...)
		}
	}
	e.Options.node = e.Options.node.addRoute(path, handler)
}

// WithShare 注册共享订阅
func (e *Engine) WithShare(group string) {
	e.Shared = true
	e.ShareGroup = group
	if group == "" {
		e.ShareGroup = "default"
	}
}

func (e *Engine) splitUrl(url string) []string {
	urlList := strings.Split(url, "/")
	for i, s := range urlList {
		if s == "" {
			urlList = append(urlList[:i], urlList[i+1:]...)
		}
	}
	return urlList
}

func (e *Engine) checkUrl(url string) {
	if url == "" {
		return
	}
	if url[0] != '/' {
		e.Logger.Error("路由必须以'/'符号开头")
		return
	}
	if url[len(url)-1] == '/' {
		e.Logger.Error("路由禁止以'/'符号开头")
		return
	}
}