import subprocess
import os
import shutil

class RegisterMachine:
    
    def __init__(self):
        self.pathfile = "/var/log/n4d/macs_id"
        self.teacherfile = "/var/log/n4d/teachermachine"
        if not os.path.exists(self.pathfile):
            open(self.pathfile,'a')
            prevmask = os.umask(0)
            os.chmod(self.pathfile,0774)
            os.lchown(self.pathfile,0,0)
            os.umask(prevmask)
        if not os.path.exists(self.teacherfile):
            open(self.teacherfile,'a')
            prevmask = os.umask(0)
            os.chmod(self.teacherfile,0774)
            os.lchown(self.teacherfile,0,0)
            os.umask(prevmask)
            
    #def __init__
    
    def get_available_id_list(self):
        registerfile = open(self.pathfile,'r')
        list=[]
        maxlimit = 0
        for line in registerfile:
            number = line.split(';')[0]
            try:
                int(number)
                list.append(int(number))
            except:
                pass
        pprocess = subprocess.Popen(['llxcfg-showvars','DHCP_HOST_MAX'],stdout = subprocess.PIPE,stderr = subprocess.PIPE)
        try:
            maxlimit = int(pproces.stdout.readline().split("'")[1])
            maxlimit += 1
        except:
            maxlimit = 81
        lavailable = range(0,maxlimit)
        list.sort()
        list.reverse()
        for i in list:
            lavailable.pop(i)
        lavailable.pop(0)
        return {'status':True,'result':lavailable}
        
    #def get_registred_machines
    
    def remove_register(self,mac):
        registerfile = open(self.pathfile,'r')
        content = registerfile.readlines()
        registerfile.close()
        found = False
        new_content = []
        idtoremove = ""
        for line in content:
            try:
                lid,lmac = line.split(';')
                lmac = lmac.strip('\n')
            except:
                continue
            if lmac == mac :
                idtoremove = lid
                found = True
            else:
                new_content.append(line)
        if not found :
            return {'status':False,'result':'MAC ' + mac + ' is not registred' }
        registerfile = open(self.pathfile,'w')
        for line in new_content:
            registerfile.write(line)
        registerfile.close()
        
        macfile = open(self.teacherfile,'r')
        maccontent = macfile.readlines()
        macfile.close()
        new_maccontent = []
        for lmac in maccontent:
            lmac = lmac.strip('\n')
            if lmac != idtoremove :
                new_maccontent.append(lmac)
        
        macfile = open(self.teacherfile,'w')
        for line in new_maccontent:
            macfile.write(line+'\n')
        macfile.close()
        
        return {'status':True,'result':'MAC '+mac+' has been removed' }
    #def register_machine
    
    
    def register_machine(self,id,mac,isteacher):
        
        teacherfile = open(self.teacherfile,'a')
        registerfile = open(self.pathfile,'r')
        content = registerfile.readlines()
        new_content = []
        found = False
        for line in content:
            try:
                lid,lmac = line.split(';')
                lmac = lmac.strip('\n')
            except:
                continue
            if id == lid :
                return {'status':False,'result':'Id '+ lid + ' is locked by MAC '+lmac }
            if lmac == mac :
                new_content.append(str(id)+';'+mac + '\n')
                found = True
            else:
                new_content.append(line)
        if not found :
            new_content.append(str(id)+';'+mac+'\n')
        if isteacher:
            teacherfile.write(str(id)+"\n")
        registerfile.close()
        registerfile = open(self.pathfile,'w')
        for line in new_content:
            registerfile.write(line)
        registerfile.close()
        return {'status':True,'result':'MAC '+ mac + ' has been registred with id ' + id }
    #def register_machine