<template>
    <li>
        <label>
            <input type="checkbox" :checked="todo.done" @change="handleCheck(todo.id)" />
            <span v-show="!todo.isEdit">{{ todo.title }}</span>
            <input 
                type="text"
                v-show="todo.isEdit"
                :value="todo.title"
                @blur="handleBlur(todo,$event)"
                ref="inputTitle"
            />
        </label>
        <button class="btn btn-danger" @click="handleDelete(todo.id)">删除</button>
        <button v-show="!todo.isEdit" class="btn btn-edit" @click="handleEdit(todo)">编辑</button>
    </li>
</template>

<script>
    import pubsub from 'pubsub-js'
    export default {
        name: "MyItem",
        // 声明接收todo对象
        props: ['todo'],
        methods: {
            //勾选或取消勾选
            handleCheck(id){
                //console.log(id)
                //通知App组件将对应的todo对象的done值取反
                // this.checkTodo(id)
                this.$bus.$emit('checkTodo',id)
            },
            //删除
            handleDelete(id){
                //console.log(id)
                if(confirm('确定删除吗？')){
                    // console.log(id)
                    // this.deleteTodo(id)
                    // this.$bus.$emit('deleteTodo',id)
                    pubsub.publish('deleteTodo',id)
                }
            },

            // 编辑
            handleEdit(todo){
                if(todo.hasOwnProperty('isEdit')){
                    todo.isEdit = true
                }else{
                    console.log('@')
                    this.$set(todo,'isEdit',true)
                }
                //nextTick指定的回调会在DOM更新完毕之后再执行
                this.$nextTick(function(){
                    this.$refs.inputTitle.focus()
                })
            },
            
            // 失去焦点回调（真正执行修改逻辑）
            handleBlur(todo,e){
                todo.isEdit = false
                if(!e.target.value.trim()) return alert('输入不能为空')
                this.$bus.$emit('updateTodo',todo.id,e.target.value)
            }
        },
    };
</script>

<style scoped>
    /*item*/
    li {
        list-style: none;
        height: 36px;
        line-height: 36px;
        padding: 0 5px;
        border-bottom: 1px solid #ddd;
    }

    li label {
        float: left;
        cursor: pointer;
    }

    li label li input {
        vertical-align: middle;
        margin-right: 6px;
        position: relative;
        top: -1px;
    }

    li button {
        float: right;
        display: none;
        margin-top: 3px;
    }

    li:before {
        content: initial;
    }

    li:last-child {
        border-bottom: none;
    }
    li:hover{
        background-color: #ddd;
    }
    li:hover button{
        display: block;
    }
</style>