时间转化描述算法

使用场景,聊天室,P2P聊天

struct TimeManager {
    
    static func showTime(msglastTime : TimeInterval ,showDetail : Bool = false) -> String {
        
        //今天的时间
        let nowDate = Date()
        let msgDate = Date(timeIntervalSince1970: msglastTime)
        var result = ""
        let components = Set([.year, .month, .day ,.weekday ,.hour, .minute, ])
        let nowDateComponents = Calendar.current.dateComponents(components, from: nowDate)
        let msgDateComponents = Calendar.current.dateComponents(components, from: msgDate)
        var hour = msgDateComponents.hour
        let OnedayTimeIntervalValue = 24*60*60  //一天的秒数
        result = TimeManager.getPeriodOfTime(time: hour!, minute: (msgDateComponents.minute)!)
        
        if (hour! > 12)
        {
            hour = hour! - 12
        }
        if(nowDateComponents.day == msgDateComponents.day) //同一天,显示时间
        {
            result = String(format:"%@ %zd:%02d",result,(hour)!,(msgDateComponents.minute)!)
        }
        else if(nowDateComponents.day == ((msgDateComponents.day)!+1))//昨天
        {
            result = showDetail ? String(format:"昨天%@ %zd:%02d",result,(hour)!,(msgDateComponents.minute)!) : "昨天"
        }
        else if(nowDateComponents.day == ((msgDateComponents.day)! + 2)) //前天
        {
            result = showDetail ? String(format:"前天%@ %zd:%02d",result,(hour)!,(msgDateComponents.minute)!) : "前天";
        }
        else if(Int(nowDate.timeIntervalSince(msgDate)) < 7 * OnedayTimeIntervalValue)//一周内
        {
            let weekDay = TimeManager.weekdayStr(dayOfWeek: (msgDateComponents.weekday)!)
            result = showDetail ? weekDay.appendingFormat("%@ %zd:%02d", result,hour!,(msgDateComponents.minute)!) : weekDay
        }
        else//显示日期
        {
            let day = String(format:"%zd-%zd-%zd", (msgDateComponents.year)!, (msgDateComponents.month)!, (msgDateComponents.day)!)
            result = showDetail ? day.appendingFormat("%@ %zd:%02d",result,hour!,(msgDateComponents.minute)!) : day
        }
        return result;
        
    }
    
    static func getPeriodOfTime(time : Int ,minute : Int) -> String{
        let totalMin = time * 60 + minute
        var showPeriodOfTime = ""
        if (totalMin > 0 && totalMin <= 5 * 60)
        {
            showPeriodOfTime = "凌晨"
        }
        else if (totalMin > 5 * 60 && totalMin < 12 * 60)
        {
            showPeriodOfTime = "上午"
        }
        else if (totalMin >= 12 * 60 && totalMin <= 18 * 60)
        {
            showPeriodOfTime = "下午"
        }
        else if ((totalMin > 18 * 60 && totalMin <= (23 * 60 + 59)) || totalMin == 0)
        {
            showPeriodOfTime = "晚上"
        }
        return showPeriodOfTime;
    }
    
    static func weekdayStr(dayOfWeek : Int) ->String{
        var daysOfWeekDict : [Int : String] = [:]
        daysOfWeekDict = [1 : "星期日" ,2 : "星期一" ,3 : "星期二" ,4 : "星期三" ,5 : "星期四" ,6 : "星期五" ,7 : "星期六"]
        return (daysOfWeekDict[dayOfWeek])!
    }

}