package data

import (
	"time"

	"github.com/google/uuid"
)

type Article struct {
	Title   string
	Created time.Time
	Desc    string
	Content string
	Tags    []string
	UUID    uuid.UUID
}

type ArticleList struct {
	addCh  chan *Article
	delCh  chan uuid.UUID
	retCh  chan *Article
	listCh chan []Article
	list   []*Article
}

func (l *ArticleList) start() {
	for {
		select {
		case article := <-l.addCh:
			l.list = append(l.list, article)
		case uuid := <-l.delCh:
			for i, article := range l.list {
				if article.UUID == uuid {
					l.list = append(l.list[:i], l.list[i+1:]...)
					l.retCh <- article
				}
			}
		case l.listCh <- func() []Article {
			var list []Article
			for _, article := range l.list {
				list = append(list, *article)
			}
			return list
		}():
		}
	}
}

func NewArticleList() *ArticleList {
	list := &ArticleList{
		addCh:  make(chan *Article),
		delCh:  make(chan uuid.UUID),
		retCh:  make(chan *Article),
		listCh: make(chan []Article),
		list:   []*Article{},
	}
	go list.start()
	return list
}

func (l *ArticleList) Add(a *Article) {
	l.addCh <- a
}

func (l *ArticleList) Release(uuid uuid.UUID) (*Article, bool) {
	l.delCh <- uuid
	article := <-l.retCh
	if article == nil {
		return nil, false
	}
	return article, true
}

func (l *ArticleList) List() []Article {
	return <-l.listCh
}