import urllib
import os
import simplejson as json
import web
from datetime import datetime
from subprocess import Popen
from socket import socket, AF_INET, SOCK_DGRAM

import settings
"""
Recieve pings from Github Webhook API and perform actions.

Examples of actions:
    - Run a script to deploy on your webserver. Yup.
    - Send a message to IRC (via an ircbot listening for UDP-messages). Yup.
    - Send an email.
    - Send a signal to an Arduino.

TODO:
 - Provide deploy log
 - Send mail to commiter on error.

Written in web.py
"""

urls = (
    '/', 'ping',
)

class ping:
    
    def script_path(self):
        return os.path.dirname(os.path.abspath(__file__))

    def url_allowed(self,url):
        for allowed_url, deploy_to in settings.REPOS.iteritems():
            if url == allowed_url:
                return True
        return False

    def POST(self):
        post_data = web.input()
        try:
            data = json.loads(post_data['payload'])
        except ValueError:
            error = "Got ping with non-JSON POST-data: \'" + str(post_data) + "\'"
            self.log(error)
            return json.dumps({'result': error})

        repo_url = data['repository']['url']
        repo_name = data['repository']['name']
        self.log("Got ping. Repo: " + repo_name + " Commit by: " + self.format_who(data['commits']) + ".")
        if not self.url_allowed(repo_url):
            not_allowed = "Repository URL \'" + repo_url + "\' not allowed." 
            self.log(not_allowed)
            return not_allowed

        # TODO: Make optional in settings
        self.update_repo(data['repository']['name'], repo_url)
        self.send_to_irc(data)

        return json.dumps({'result' : "Thank you :-)"})

    def update_repo(self, name, url):
        if not settings.REPOS[url]:
            self.log("No deploy path defined.")
            return
        # run the deployscript
        args = ['/bin/sh', settings.DEPLOY_SCRIPT_PATH,
            settings.REPOS[url], name]
        self.log("Updating repo: \'" + " ".join(args) + "\'")
        p = Popen(args)

    def format_who(self, commits):
        who = ""
        if len(commits) == 1:
            who = commits[0]['author']['name']
        else:
            who = set() # unique entries
            for commit in commits:
                who.add(commit['author']['name'])
            who = ", ".join(who)

        return who 

    def format_for_irc(self, data):
        # String to be sent to irc.
        who = self.format_who(data['commits'])
        return "Git commit: \'{0}\': {1} by {2}".format(data['repository']['name'],
                                               data['compare'],
                                               who)

    def send_to_irc(self, data):
        # Send the message to snurr via UDP.
        data = self.format_for_irc(data)
        udp = socket(AF_INET, SOCK_DGRAM)
        udp.sendto(data, settings.IRC_BOT_HOST)

    def log(self, msg):
        # Log pings.
        log = open(self.script_path() + "/pings.log", "a+")
        log.write(datetime.now().isoformat() + ": " + msg + "\n")
        log.close()
   
app = web.application(urls, globals(), autoreload=True)
application = app.wsgifunc()

if __name__ == "__main__":
    app.run()