import re
import dircache

days_in_months      = [31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31]
days_in_months_leap = [31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31]

def leap_year(year):
        if year % 4 == 0:
                if year % 100 != 0 or year % 400 == 0:
                        return True
                else:
                        return False
        else:
                return False

def date_dist(date1, date2):
        if date1 < date2:
                sign = -1
                date1, date2 = date2, date1
        else:
                sign = 1

        year1  = int(date1[0:4])
        month1 = int(date1[4:6])
        day1   = int(date1[6:8])
        year2  = int(date2[0:4])
        month2 = int(date2[4:6])
        day2   = int(date2[6:8])

        year = year2
        daycount = 0
        while year <= year1:
                if(leap_year(year)):
                        daycount += 366
                else:
                        daycount += 365
                year += 1
        
        if leap_year(year2):
                my_days = days_in_months_leap
        else: 
                my_days = days_in_months

        month1 -= 1
        month2 -= 1
        month = 0
        while month < month2:
                daycount -= my_days[month]
                month += 1
        
        daycount -= day2

        if leap_year(year1):
                my_days = days_in_months_leap
        else: 
                my_days = days_in_months

        month = 11
        while month >= month1:
                daycount -= my_days[month]
                month -= 1

        daycount += day1

        return daycount*sign

file_re = re.compile(r'2CSNAP-([0-9]{8})-([0-9]{4})-([^.]+)\.iso\.(bz2|gz)')

def cmp_filtered(filt1, filt2):
        if filt1.date != filt2.date:
                return filt1.date - filt2.date
        else:
                return filt1.time - filt2.time

class filtered_file(object):
        cmp = cmp_filtered
        def __init__(self, name='', date='', time='', tag=''):
                self.name = name
                self.date = date
                self.time = time
                self.tag = tag


file_list = dircache.listdir('.')[:]

filtered_list = []

for file_name in file_list:
        file_match = file_re.match(file_name)
        if file_match:
                fname = file_match.string
                fdate = int(file_match.expand(r'\1'))
                ftime = int(file_match.expand(r'\2'))
                ftag  = file_match.expand(r'\3')
                filtered_list.append(filtered_file(fname, fdate, ftime, ftag))

tag_set = set([x.tag for x in filtered_list])

tag_dict = {}

for tag in tag_set:
        tag_dict[tag] = []

for file in filtered_list:
        tag_dict[file.tag].append(file)

for key in tag_dict.keys():
        tag_dict[key].sort(cmp=filtered_file.cmp, reverse=True)
        keep_count=0
        last_date=-1
        list_len = len(tag_dict[key])
        remove_list = []
        for i,file in enumerate(tag_dict[key]):
                if i < list_len - 1:
                        distance = date_dist(str(file.date), str(tag_dict[key][i+1].date
))
                else:
                        distance = 30 #save the last one for historical reasons
                if keep_count < 30:
                        if last_date == file.date:
                                #print "remove",
                                remove_list.append(file.name)
                                pass
                        else:
                                keep_count += 1
                                #print "keep",
                                #keep_list.append(file)
                                last_date = file.date
                elif keep_count < 45:
                        if date_dist(str(last_date),str(file.date)) + distance <= 7:
                                #print "remove",
                                remove_list.append(file.name)
                                pass
                        else:
                                keep_count += 1
                                #print "keep",
                                #keep_list.append(file)
                                last_date = file.date
                else: 
                        if date_dist(str(last_date),str(file.date)) + distance <= 30:
                                #print "remove"
                                remove_list.append(file.name)
                                pass
                        else:
                                #keep_list.append(file)
                                #print "keep"
                                last_date = file.date
                #print "%s made on %d is #%d" % (file.tag, file.date, i)
        
        #print key
        #print "------------------"
        #for dist in [date_dist(str(keep_list[i].date), 
        #                       str(keep_list[i+1].date)) for i in range(0, len(keep_lis
t) - 1)]:
        #print dist

        for filename in remove_list:
                print filename