<?php
 
	function RelativeTimeString($timestamp) {
        $minute = 60;
        $hour = $minute * 60;
        $day = $hour * 24;
        $month = 30 * $day;
        $year = 12 * $month;
 
        $delta = floor(time()-$timestamp);
        if ($delta < 2 )           return 'Agorinha';
        if ($delta < 1 * $minute)  return "Há $delta segundos";
        if ($delta < 2 * $minute)  return 'Há um minuto';
        if ($delta < 45 * $minute) return 'Há '.round($delta / $minute).' minutos';
        if ($delta < 90 * $minute) return 'Há uma hora';
        if ($delta < 24 * $hour)   return 'Há '.round($delta / $hour).' horas';
        if ($delta < 48 * $hour)   return 'Ontem';
        if ($delta < 30 * $day)    return 'Há '.round($delta / $day).' dias';
        if ($delta < 45 * $day)    return 'Há um mês';
        if ($delta < 12 * $month)  return 'Há '.round($delta / $month).' meses';
        if ($delta < 18 * $month)  return 'Há um ano';
        return 'Há '.round($delta / $year).' anos';
    }
 
    // Duas coisas: primeiro, cuidado com o cache do IDEONE,
    // ele guarda o output de quando o código foi executado, e não visualizado
    // segundo: o timezone do servidor do IDEONE provavelmente não bate com o seu,
    // então faça testes com horários UTC.
 
	echo RelativeTimeString(mktime(0,0,0,5,31,2013)).PHP_EOL;
	echo RelativeTimeString(mktime(0,0,0,3,31,2017)).PHP_EOL;

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