<template>

    <button @click="stop">停止</button>
    <button @click="start">游戏开始</button>
    <div style="color: red; text-align: center;font-size: 25px">score:{{scroce}}</div>

    <div class="box" :style="{width :boxWidth +'px', height:boxHeight +'px'}">
        <div class="str">{{str}}</div>
        <div class="kuaiBox">
            <div class="kuai" v-for="(item,index) in arr" :key="index" :style="{opacity :item.active ? '0':'1'}"></div>
        </div>
        <div class="ball" :style="{left :x + 'px', top : y + 'px', width : ball +'px', height: ball+'px'}"></div>
        <div class="bottomMove"
             :style="{left :mx + 'px' , top : my + 'px',width :moveBottomW +'px',height : moveBottomH+'px'  }"></div>
    </div>
</template>

<script setup>
    import {onMounted, onUnmounted, reactive, toRefs} from 'vue'

    const boxWidth = 500, // 场景宽度
        boxHeight = 300, // 场景高度
        ball = 10,//小球的宽高
        moveBottomH = 5,//移动方块高度
        moveBottomW = 100//移动方块快读

    const strArr = '恭喜你,挑战成功!!'

    //用reactive 保存一些可观察信息
    const state = reactive({
        x: boxWidth / 2 - ball / 2,  // 小球x轴位置信息 计算默认位置在中间
        y: boxHeight - ball - moveBottomH, // 小球Y轴的位置信息 计算默认位置在中间
        mx: boxWidth / 2 - moveBottomW / 2, //移动方块的位置信息 计算默认位置在中间
        my: boxHeight - moveBottomH, // 移动方块y轴的的位置信息  计算默认位置在中间
        // 被打击方块的数组
        arr: Array.from({length: 50}, (_, index) => {
            return {
                index,
                active: false
            }
        }),
        str: '', // 返回挑战成功字眼
        scroce: 0 // 分数
    })
    // 用toRefs将观察对象的信息解构出来供模板使用 
    const {x, y, mx, my, arr, str, scroce} = toRefs(state)
    let timer = null, // 小球定时器
        speed = 3,// 小球速度
        map = {x: 10, y: 10},
        timer2 = null, // 挑战成功字眼显示定时器
        index = 0//挑战成功字眼续个显示的索引值

    // 挑战成功字眼续个显示的方法
    const strFun = () => {
        if (strArr.length === index) clearInterval(timer2)
        state.str += strArr.substr(index, 1)
        index++
    }

    
    //移动小球的方法  
    // 1.这里同过变量map 对象来记录坐标信息, 确定小球碰到 左右上 及移动方块是否回弹
    // 2.循环砖块检测小球碰撞到砖块消失
    const moveBall = () => {
        const {offsetTop, offsetHeight, offsetLeft, offsetWidth} = document.querySelector('.bottomMove')
        if (state.x <= 0) {
            map.x = speed
        } else if (state.x > boxWidth - ball) {
            map.x = -speed
        }
        if (state.y <= 0) {
            map.y = speed
        }
        if (state.y >= offsetTop - offsetHeight &&
            state.y <= offsetTop + offsetHeight &&
            state.x >= offsetLeft &&
            state.x < offsetLeft + offsetWidth) {
            map.y = -speed
        }
        if (state.y > boxHeight) {
            clearInterval(timer)
            alert('game over')
            window.location.reload()
        }
        Array.from(state.arr).forEach((item, index) => {
            const {
                offsetLeft,
                offsetTop,
                offsetWidth,
                offsetHeight
            } = document.querySelectorAll('.kuai')[index]
            if (state.x > offsetLeft
                && state.x < offsetLeft + offsetWidth
                && state.y > offsetTop
                && state.y < offsetTop + offsetHeight) {
                if (!state.arr[index].active) {
                    state.scroce += 100
                }
                state.arr[index].active = true
            }
        })
        if (Array.from(state.arr).every(item => item.active)) {
            clearInterval(timer)
            timer2 = setInterval(strFun, 1000)
        }
        state.x = state.x += map.x
        state.y = state.y += map.y
    }

    //移动方块左右移动方法 ,接住小球
    const bottomMove = ev => {
        if (ev.code === 'Space') clearInterval(timer)
        switch (ev.key) {
            case 'ArrowRight':
                state.mx += 100
                break
            case  'ArrowLeft':
                state.mx -= 100
                break
        }
        state.mx = state.mx < 0 ? 0 : state.mx
        state.mx = state.mx > boxWidth - moveBottomW ? boxWidth - moveBottomW : state.mx
    }
    // 暂停游戏
    const stop = () => {
        clearInterval(timer)
    }
    // 开始游戏 
    const start = () => {
        timer = setInterval(moveBall, 20)
    }
    
    // 绑定移动方块事件
    onMounted(() => {
        document.addEventListener('keyup', bottomMove)
    })
    // 移动出移动方块事件
    onUnmounted(() => {
        clearInterval(timer)
    })
</script>

<style>

    .bottomMove {
        width: 100px;
        height: 10px;
        background: red;
        position: absolute;
        transition-duration: 100ms;
        transition-timing-function: ease-out;
    }

    .ball {
        width: 20px;
        height: 20px;
        background-color: red;
        border-radius: 50%;
        position: absolute;
    }

    .kuaiBox {
        display: flex;
        flex-wrap: wrap;
    }

    .kuai {
        width: 30px;
        height: 10px;
        background: red;
        margin: 10px;
        transition-duration: 100ms;
        transition-timing-function: ease-in;
    }

    .str {
        text-align: center;
        font-size: 50px;
        color: red;

    }

    .box {

        justify-content: center;
        width: 500px;
        height: 500px;
        margin: 0 auto;
        position: relative;
        border: 5px solid red;
        overflow: hidden;
    }

    .picker {
        width: 50px;
        height: 50px;
    }
</style>