import os
import subprocess
from constant import WHITE_LIST, KEEP_FILES, DATE, MAIL_MSG, MOVE_MSG

class Cleaner():
    def __init__(self, user_dir, mailer=None):
        self.user_dir = user_dir
        self.mailer = mailer

    def run(self, test=True, notify_stage=True):
        '''
            notify_stage=1, test=1: 不會刪，不會寄信(只寄給開發人員)
            notify_stage=1, test=0: 不會刪，會寄信 （提醒階段）
            notify_stage=0, test=1: 不會刪，不會寄信(確認)
            notify_stage=0, test=0: 會刪除，不會寄信（刪除階段）
        '''
        username = self.user_dir.split('/')[-1]
        if username in WHITE_LIST:
            print(f'    WHITE LIST: {username}')
            return

        remove_objs = []
        for obj in sorted(os.listdir(self.user_dir)):
            if obj in KEEP_FILES:
                continue

            obj = obj.replace(' ', '\ ')

            # stat {file or dir}:
            #       get Create, modified information
            # grep Modify:
            #       get Modified time
            # awk:
            #       -F ' ': use space to split the data
            #       print $2: column 2 (get date)
            modify_date = subprocess.getoutput(f"stat {self.user_dir}/{obj} | grep Modify | awk -F ' ' '{{print $2}}'" )

            if modify_date < DATE:
                remove_objs.append((obj, modify_date))
                print(f'    {modify_date} {obj}')

        if notify_stage and len(remove_objs) != 0:
            self.notify(username, test, remove_objs)

        elif not notify_stage and len(remove_objs) != 0:
            # delete files
            remove_obj_names = [ name for name, date in remove_objs ]
            if test:
                command = 'rm -rf {}'.format(" ".join(remove_obj_names))
                print(f'    we will run:\n      {command}')
            else:
                if not os.path.isdir(f'/volume1/cmlabhome/home_backup/{username}'):
                    os.mkdir(f'/volume1/cmlabhome/home_backup/{username}')

                msg = ""
                for name, date in remove_objs:
                    if name[0] != '.' and 'conda' not in name:
                        command = f'mv {self.user_dir}/{name} /volume1/cmlabhome/home_backup/{username}/{name}'
                    else:
                        command = f'rm -rf {self.user_dir}/{name}'
                    print(command)
                    subprocess.getoutput(command)
                    msg += f"    - {name}\n"
                msg = MOVE_MSG.format(msg)

                with open(f'{self.user_dir}/PLEASE_READ_ME', 'w') as fp:
                    fp.write(msg)

    def notify(self, username, test, remove_objs):
        if self.mailer == None:
            return

        if test:
            receiver = 'snsd0805@cmlab.csie.ntu.edu.tw'
        else:
            receiver = f'{username}@cmlab.csie.ntu.edu.tw'
        sender = 'unix_manager@cmlab.csie.ntu.edu.tw'
        subject = f'[網管通知] CML Server 清理預計被移除的內容({username})'
        msg = ''
        for obj, date in remove_objs:
            msg += f'<li>{date} - {obj}</li>'
        msg = MAIL_MSG.format(username, msg)

        self.mailer.send(sender, receiver, subject, msg)