js通过某个时间戳获取昨天、今天、明天、后天的时刻

function getTimeTransition(timestamp){
        let now_timestamp = (Date.parse(new Date())) / 1000;//现在时间戳
        let today_timestamp = getStartEndTime();//今天的起始时间戳
        let yesterday_timestamp = getStartEndTime(1);//昨天的起始时间戳
        let tomorrow_timestamp = getStartEndTime(-1);//明天的起始时间戳
        let acquired_timestamp = getStartEndTime(-2);//后天的起始时间戳
        if(today_timestamp[0] < timestamp && today_timestamp[1] > timestamp){
            //今日时间戳
            return "今日"+formatDate(timestamp,"h:i")
        }else{
            //非今日时间戳
            if((timestamp - now_timestamp) > 0){
                //将来时间
                console.log("将来时间")
                if(tomorrow_timestamp[0] < timestamp && tomorrow_timestamp[1] > timestamp){
                    return "明天"+formatDate(timestamp,"h:i")
                }else{
                    if(acquired_timestamp[0] < timestamp && acquired_timestamp[1] > timestamp){
                        return "后天"+formatDate(timestamp,"h:i")
                    }else{
                        let time_count = parseInt((timestamp - now_timestamp) / 86400);
                        if(time_count < 4){
                            return time_count + "天后"+formatDate(timestamp,"h:i");
                        }else{
                            return formatDate(timestamp,"m-d h:i")
                        }
                    }
                }
            }else{
                //过去时间
                console.log("过去时间")
                if(yesterday_timestamp[0] < timestamp && yesterday_timestamp[1] > timestamp){
                    return "昨天"+formatDate(timestamp,"h:i")
                }else{
                    let time_count = parseInt((now_timestamp - timestamp) / 86400);
                    if(time_count < 4){
                        return  time_count + "天前"+formatDate(timestamp,"h:i");
                    }else{
                        return formatDate(timestamp,"m-d h:i")
                    }
                }
            }
        }
        //获取某天的起止时间戳（今日传入0，昨日传入1，明日传入-1）
        function getStartEndTime (num = 0) {
            // 一天的毫秒数
            const MillisecondsADay = 24*60*60*1000 * num
            // 今日开始时间戳
            const todayStartTime = new Date(new Date().setHours(0, 0, 0, 0)).getTime()
            // 今日结束时间戳
            const todayEndTime = new Date(new Date().setHours(23,59,59,999)).getTime()
            // 昨日开始时间戳
            const yesterdayStartTime = todayStartTime - MillisecondsADay
            // 昨日结束时间戳
            const yesterdayEndTime = todayEndTime - MillisecondsADay
            return [
                parseInt(yesterdayStartTime / 1000),
                parseInt(yesterdayEndTime / 1000)
            ]
        }
        //时间戳转指定时间
        function formatDate(Unix,formate = 'Y-m-d h:i:s',complement = true,alike = false){
            let current = new Date(Date.parse(new Date()));
            let current_year = current.getFullYear();
            let current_month = current.getMonth() + 1;
            let current_date = current.getDate();
            let timestamp = new Date(Unix * 1000);
            let year = timestamp.getFullYear();
            let month = timestamp.getMonth() + 1;
            let date = timestamp.getDate();
            let hour = timestamp.getHours();
            let minute = timestamp.getMinutes();
            let second = timestamp.getSeconds();
            if(alike && current_year === year){
                formate = formate.replace(/Y-/g,'');
            }else{
            }
            if(alike && current_year === year && current_month === month && current_date === date){
                formate = formate.replace(/m-d /g,'');
            }
            if(complement){
                month = month < 10 ? '0' + month : month;
                date = date < 10 ? '0' + date : date;
                hour = hour < 10 ? '0' + hour : hour;
                minute = minute < 10 ? '0' + minute : minute;
                second = second < 10 ? '0' + second : second;
            }
            formate = formate.replace(/Y/g,year);
            formate = formate.replace(/m/g,month);
            formate = formate.replace(/d/g,date);
            formate = formate.replace(/h/g,hour);
            formate = formate.replace(/i/g,minute);
            formate = formate.replace(/s/g,second);
            return formate;
        }
    }
    console.log(getTimeTransition(1635242400));