import json
import logging
import smtplib
import os
from email.message import EmailMessage
from email.mime.text import MIMEText
from email.mime.multipart import MIMEMultipart

from pyexecplugins.pyexecplugins import PyExecPlugin

class Plugin(PyExecPlugin):
    name = "Mail"

    taskdef = {
        "name" : "pymail",
        "description" : "Send mail with pymail worker",
        "inputKeys" : ["from", "to", "bcc", "cc", "text", "html", "extra_vars"],
        "outputKeys" : [],
        "ownerEmail" : "m.lettere@gmail.com"
    }

    def getProtocol(self, config):
        if config is not None and config["pymail"] is not None:
            return (config["pymail"].get("protocol") or "plain")
        else:
            return "plain"

    def getConfig(self, config, key):
        if config is not None and config["pymail"] is not None:
            return (config["pymail"].get(key) or self.defaults[key])
        else:
            return self.defaults[key]

    def getDefaults(self, protocol):
        defaults = {"server" : "localhost", "user" : None, "password" : None}
        if protocol == "ssl":
            defaults["port"] = 465
        elif protocol == "starttls":
            defaults["port"] = 587
        else:
            defaults["port"] = 25
        return defaults

    def __init__(self, data, config):
        super().__init__(data)
        if config is not None:
            self.protocol = self.getProtocol(config)
            self.defaults = self.getDefaults(self.protocol)
            self.server = self.getConfig(config, "server")
            self.port = self.getConfig(config, "port")
            self.user = os.environ.get('smtp_user', self.getConfig(config, "user"))
            self.password = os.environ.get('smtp_pass', self.getConfig(config, "password"))

        logging.getLogger("pyexec").debug("Parsed config" + self.password)

        self.frm = data.get("from") or "noreply@noreply.org"
        self.to = data.get("to") or []
        self.to = [self.to] if isinstance(self.to, str) else self.to
        self.bcc = data.get("bcc") or []
        self.bcc = [self.bcc] if isinstance(self.bcc, str) else self.bcc
        self.cc = data.get("cc") or []
        self.cc = [self.cc] if isinstance(self.cc, str) else self.cc
        self.subject = (data.get("subject") or "No subject").format_map(data.get("extra_vars") or {})
        self.extra_vars = data.get("extra_vars") or {}
        self.text = data.get("text")
        if self.text is not None:
            self.text = self.text.format_map(data.get("extra_vars") or {})
        self.html = data.get("html")
        if self.html is not None:
            self.html = self.html.format_map(data.get("extra_vars") or {})

    def sendMail(self):
        logging.getLogger("pyexec").info("Sending mail from %s to %s subj %s ", self.frm, self.to, self.subject)
        m = self.buildMessage()
        if self.protocol == "ssl":
            self.sendSSLMail(m)
        elif self.protocol == "starttls":
            self.sendSTARTTLSMail(m)
        else:
            self.sendPlainMail(m)
        logging.getLogger("pyexec").debug("Mail sent.")        

    def buildMessage(self):
        if self.html is not None:
            m = MIMEMultipart("alternative")
            if self.text is not None:
                m.attach(MIMEText(self.text, "plain"))
            else:
                m.preamble = "You won't be reading this email without multipart/html support"
            m.attach(MIMEText(self.html, "html"))
        else:
            m = EmailMessage()
            m.set_content(self.text)
        m["Subject"] = self.subject
        m["From"] = self.frm
        m["To"] = ', '.join(self.to)
        m["Cc"] = ', '.join(self.cc)
        m["Bcc"] = ', '.join(self.bcc)
        logging.getLogger("pyexec").debug("Message built")
        return m

    def sendPlainMail(self, m):
        logging.getLogger("pyexec").debug("Sending mail %s - %s - %s",self.server, self.port, self.user)
        s = smtplib.SMTP(host=self.server, port=self.port)
        s.send_message(m)
        s.quit()

    def sendSSLMail(self):
        raise Exception("Not yet supported")

    def sendSTARTTLSMail(self, m):
        logging.getLogger("pyexec").debug("Sending STARTTLS mail %s - %s - %s",self.server, self.port, self.user)
        s = smtplib.SMTP(host=self.server, port=self.port)
        s.starttls()
        s.login(self.user, self.password)
        s.send_message(m)
        s.quit()

    def execute(self):
        return self.sendMail()