import logging
import smtplib
import mimetypes
from email.mime.multipart import MIMEMultipart
from email.mime.image import MIMEImage
from email.mime.audio import MIMEAudio
from email.mime.base import MIMEBase
from email.mime.text import MIMEText
from email.utils import formatdate
from email import encoders

class SmtpMailer(object):
    """simple smtp mailer class
    
    mailer = SmtpMailer(mail_from, user, passwd, mail_server, mail_port, ssl, tls)
    mailer.send(recipients, subject, body, attachment_files)    
    
    :param recipients might be a list of string or single string
    :param attachment_files is a dict of {filename:location} 
    it tries to guess the mimetype and attach the file
    """

    def __init__(self, mail_from, user, passwd, mail_server,
                    mail_port=None, ssl=False, tls=False):
        
        self.mail_from = mail_from
        self.mail_server = mail_server
        self.mail_port = mail_port
        self.user = user
        self.passwd = passwd
        self.ssl = ssl
        self.tls = tls
        self.debug = False
        
    def send(self, recipients=[], subject='', body='', attachment_files={}):

        if isinstance(recipients, basestring):
            recipients = [recipients]
        if self.ssl:
            smtp_serv = smtplib.SMTP_SSL(self.mail_server, self.mail_port)
        else:
            smtp_serv = smtplib.SMTP(self.mail_server, self.mail_port)

        if self.tls:
            smtp_serv.starttls()
         
        if self.debug:    
            smtp_serv.set_debuglevel(1)

        smtp_serv.ehlo("mailer")

        #if server requires authorization you must provide login and password
        smtp_serv.login(self.user, self.passwd)

        date_ = formatdate(localtime=True)
        msg = MIMEMultipart()
        msg['From'] = self.mail_from
        msg['To'] = ','.join(recipients)
        msg['Date'] = date_
        msg['Subject'] = subject
        msg.preamble = 'You will not see this in a MIME-aware mail reader.\n'

        msg.attach(MIMEText(body))

        if attachment_files:
            self.__atach_files(msg, attachment_files)

        smtp_serv.sendmail(self.mail_from, recipients, msg.as_string())
        logging.info('MAIL SEND TO: %s' % recipients)
        smtp_serv.quit()


    def __atach_files(self, msg, attachment_files):
        if isinstance(attachment_files, dict):
            for f_name, msg_file in attachment_files.items():
                ctype, encoding = mimetypes.guess_type(f_name)
                logging.info("guessing file %s type based on %s" , ctype, f_name)
                if ctype is None or encoding is not None:
                    # No guess could be made, or the file is encoded (compressed), so
                    # use a generic bag-of-bits type.
                    ctype = 'application/octet-stream'
                maintype, subtype = ctype.split('/', 1)
                if maintype == 'text':
                    # Note: we should handle calculating the charset
                    file_part = MIMEText(self.get_content(msg_file), 
                                         _subtype=subtype)
                elif maintype == 'image':
                    file_part = MIMEImage(self.get_content(msg_file), 
                                          _subtype=subtype)
                elif maintype == 'audio':
                    file_part = MIMEAudio(self.get_content(msg_file), 
                                          _subtype=subtype)
                else:
                    file_part = MIMEBase(maintype, subtype)
                    file_part.set_payload(self.get_content(msg_file))
                    # Encode the payload using Base64
                    encoders.encode_base64(msg)
                # Set the filename parameter
                file_part.add_header('Content-Disposition', 'attachment', 
                                     filename=f_name)
                file_part.add_header('Content-Type', ctype, name=f_name)
                msg.attach(file_part)
        else:
            raise Exception('Attachment files should be' 
                            'a dict in format {"filename":"filepath"}')    

    def get_content(self, msg_file):
        '''
        Get content based on type, if content is a string do open first
        else just read because it's a probably open file object
        @param msg_file:
        '''
        if isinstance(msg_file, str):
            return open(msg_file, "rb").read()
        else:
            #just for safe seek to 0
            msg_file.seek(0)
            return msg_file.read()