package gtp

import (
	"sync"
)

type EngineContainer struct {
	*Options // 通用配置

	// 实例容器,动态扩容,暂不限制使用数量
	data []*GtpEngine

	*sync.RWMutex
}

func NewGtpEngineContainer(opts *Options) *EngineContainer {
	return &EngineContainer{
		Options: opts,
		data:    make([]*GtpEngine, 0),
		RWMutex: &sync.RWMutex{},
	}
}

// Get 获取空闲实例
func (e *EngineContainer) Get(opts ...Option) *GtpEngine {
	e.Lock()
	defer e.Unlock()

	for _, ngin := range e.data {
		sess := ngin.Session()
		if !sess.Exists(KeyInUse) {
			return ngin
		}
		if !sess.Attribute(KeyInUse).(bool) {
			return ngin
		}
	}
	// 没有空闲的实例，创建之
	var ngin *GtpEngine
	if len(opts) == 0 {
		ngin = NewGtpEngine(WithDevMode(e.DevMode), WithTimeout(e.Timeout))
	} else {
		ngin = NewGtpEngine(opts...)
	}
	e.data = append(e.data, ngin)

	return ngin
}

// GetById 获取或创建给定ID的实例
func (e *EngineContainer) GetById(id int64, opts ...Option) *GtpEngine {

	e.RLock()
	for _, ngin := range e.data {
		sess := ngin.Session()
		if sess.Id() == id {
			e.RUnlock()
			return ngin
		}
	}
	e.RUnlock()

	// 未能获取到指定实例，创建之
	ngin := e.Get(opts...)

	ngin.Bind(id)

	return ngin
}