import os
from configparser import ConfigParser
import json
import smtplib
from email.mime.text import MIMEText
from email.mime.multipart import MIMEMultipart

import datetime

import requests

SMTP_PORT = 0
SMTP_SERVER = 'null'
SENDER_EMAIL = 'a@b.c'
RECEIVER_EMAIL = 'd@e.f'

def main():
    global SMTP_PORT, SMTP_SERVER, SENDER_EMAIL, RECEIVER_EMAIL

    script_dir = os.path.dirname(__file__)
    conf_file = os.path.join(script_dir, 'conf.ini')
    template_file = os.path.join(script_dir, 'template.html')

    parser = ConfigParser()
    parser.read(conf_file)

    SMTP_PORT = parser.get('config', 'smtp_port')
    SMTP_SERVER = parser.get('config', 'smtp_server')
    SENDER_EMAIL = parser.get('config', 'sender_email')
    RECEIVER_EMAIL = parser.get('config', 'receiver_email')

    projects = json.loads(parser.get('projects', 'projects'))
    new_releases = []
    new_projects = []

    if not parser.has_section('release'):
        parser.add_section('release')

    for project in projects:
        last_release = get_last_release(project)

        if not parser.has_option('release', project):
            new_projects.append(last_release)
        else:
            last_config_tag = parser.get('release', project)
            if last_config_tag != last_release['release_tag']:
                last_release['preview_tag'] = last_config_tag
                new_releases.append(last_release)
        parser.set('release', project, last_release['release_tag'])

    if not new_releases and not new_projects:
        print('No new projets or new release detected. Bye!')
        return

    content = ""

    for new_r in new_releases:
        content += """
        <li><a href="{}" target="_blank">{}</a>: new release <a href="{}" target="_blank">{}</a> available (old: {}).
        (published {})</li>
        """.format(
            new_r['release_url'],
            new_r['project_name'],
            new_r['release_url'],
            new_r['release_tag'],
            new_r['preview_tag'],
            convert_date(new_r['published_date']))
    for new_p in new_projects:
        content += """
        <li><a href="{}" target="_blank">{}</a> was added to your configuration. Last release: <a href="{}" target="_blank">{}</a>
        (published {})</li>""".format(
            new_p['release_url'],
            new_p['project_name'],
            new_p['release_url'],
            new_p['release_tag'],
            convert_date(new_p['published_date']))

    # print(content)

    with open(template_file, 'r') as f_template:
        template = f_template.read()

    send_mail(template.replace('{{content}}', content))

    with open('conf.ini', 'w') as configfile:
        parser.write(configfile)

def get_last_release(project):
    url = 'https://api.github.com/repos/{}/releases/latest'.format(project)
    result = requests.get(url)

    print(project)
    print(url)
    release = result.json()
    release_tag = release['tag_name']
    published_date = release['published_at']
    # body = release['body']
    release_url = release['html_url']

    return {'release_tag': release_tag,
            'published_date': published_date,
            # 'body': body,
            'project_name': project,
            'release_url': release_url}

def send_mail(content):
    message = MIMEMultipart("alternative")
    message["Subject"] = "New Github releases"
    message["From"] = SENDER_EMAIL
    message["To"] = RECEIVER_EMAIL

    # part1 = MIMEText(text, "plain")
    part2 = MIMEText(content, "html")

    # message.attach(part1)
    message.attach(part2)

    with smtplib.SMTP(SMTP_SERVER, SMTP_PORT) as server:
        server.sendmail(SENDER_EMAIL, RECEIVER_EMAIL, message.as_string())

def convert_date(date: str, format='%d %b %Y at %H:%M') -> str:
    return datetime.datetime.strptime(date, "%Y-%m-%dT%H:%M:%SZ").strftime(format)

if __name__ == "__main__":
    main()