#!/usr/bin/env python

# Fire up virtualenv
activate_this = "venv/bin/activate_this.py"
execfile(activate_this, dict(__file__=activate_this))

######
### What are we going to be using today?
######

import os
import time
import uuid
from subprocess import call
import sqlite3


######
### Classes!
#####

class _db:

    def _connect(self, db="jobs.db"):
        """ connect()
        connects to the sqlite database, uses a try/except to return False if it fails
        """
        try:
            self._conn = sqlite3.connect('jobs.db')
            self._c = self._conn.cursor()
            return True
        except:
            return False

    def commit(self):
        """ commit()
        commits any pending changes to the database file.
        """
        return self._conn.commit()

    def query(self,query,returns="list",timeout=10,db="jobs.db"):
        """ query()
        run a query against the sqlite database. will attempt to reconnect if necessary.
        will timeout after $timeout seconds.
        """
        t = time.time() + timeout
        while True:
            try:
                self._c.execute(query)
                break
            except:
                if db != "jobs.db":
                    self._connect(db=db)
                else:
                    if not self._connect():
                        print "ERROR: Cannot connect to database."
                time.sleep(2)

            if time.time() > t:
                print 'ERROR: Query timed out.'
                break
        
        if returns == "list":
            return self._c.fetchall()
        elif returns == "one":
            return self._c.fetchone()


# Job Class
class Job:
    def __init__(self, due = time.time() + 3600, command = 'true', originator = 'indenture',
                 completed = False, arguments = ''):
        self.arguments = arguments
        self.due = due
        self.command = command
        self.uuid = uuid.uuid4()
        self.originator = originator
        self.completed = completed

    def _full_exec(self):
        """ _full_exec()
        returns the full command to be executed with the arguments
        """
        return self.command+' '+self.arguments

    def _disconnect(self):
        """ _disconnect()
        flushes writes to sqlite and closes the connection
        """
        self._conn.commit()
        self._c.close()

    def describe(self,prints=True,returns=False):
        """ describe():
        a public function that describes the job to be completed.
        """
        description = []
        description.append('UUID: ' + self.uuid)
        description.append('Commmand: ' + self._full_exec())
        description.append('Due Date: ' + self.what_time())
        if self.completed:
            description.append('Completion: Completed')
        else:
            description.append('Completion: Incomplete')

        if prints == True:
            print '\n'.join(description)
        if returns == True:
            return '\n'.join(description)

    def do_work(self):
        """ do_work()
        actually performs the work to be completed.
        """
        print self._full_exec().split()
        r = call(self._full_exec().split())
        if not r > 0:
            return True
        else:
            return False

    def open(self, uuid):
        """ open()
        runs a query to populate with the information of an existing job
        in the database
        """
        jobsdb = _db()
        
        data = jobsdb.query('SELECT uuid,command,arguments,due,originator,completed \
                            FROM jobs WHERE uuid = "' + uuid + '" LIMIT 1;', returns="one")
        print data
        if data:
            (self.uuid, self.command, self.arguments, self.due, self.originator, self.completed) = data


    def save(self):
        """ save()
        saves the current job to the database. will determine if it's 
        necessary insert a new job or update an old job.
        """
    
        jobsdb = _db()

        test = 'SELECT uuid FROM jobs WHERE uuid = "' + str(self.uuid) + '";'
        if len(jobsdb.query(test,returns="list")) > 0:
            query = 'UPDATE jobs SET '
            query += 'command = "' + self.command + '", '
            query += 'arguments = "' + self.arguments + '", '
            query += 'due = "' + str(self.due) + '", '
            query += 'originator = "' + self.originator + '", '
            if self.completed:
                query += 'completed = 1 '
            else:
                query += 'completed = 0 '
            query += 'WHERE uuid = "'+str(self.uuid)+'" LIMIT 1;'

            print query

            jobsdb.query(query)
            jobsdb.commit()
        else:
            query = 'INSERT INTO jobs (uuid, command, arguments, due, originator, completed) '
            query += 'VALUES ('
            query += '"' + str(self.uuid) + '",'
            query += '"' + self.command + '",'
            query += '"' + self.arguments + '",'
            query += '"' + str(self.due) + '",'
            query += '"' + self.originator + '",'
            if self.completed:
                query += str(1)
            else:
                query += str(0)
            query += ');'
            jobsdb.query(query)
            jobsdb.commit()

    def what_time(self):
        """ what_time()
        returns a prettified version of the due date.
        """
        return pretty_date(self.due)

    def what_work(self):
        """ what_work()
        public function to see what work is going to be done.
        """
        return self._full_exec()


######
### Helper Functions
######


def pretty_date(time=False):
    """ pretty_date()
    Get a datetime object or a int() Epoch timestamp and return a
    pretty string like 'an hour ago', 'Yesterday', '3 months ago',
    'just now', etc
    """
    from datetime import datetime
    now = datetime.now()
    if type(time) is int:
        d = datetime.fromtimestamp(time)
    elif type(time) is float:
        d = datetime.fromtimestamp(time)
    elif not time:
        diff = now - now
    
    if now > d:
        diff = now - d
    elif d > now:
        diff = d - now
    else:
        diff = now - now

    second_diff = diff.seconds
    day_diff = diff.days

    if now > d:
        if day_diff == 0:
            if second_diff < 10:
                return "just now"
            if second_diff < 60:
                return str(second_diff) + " seconds ago"
            if second_diff < 120:
                return  "a minute ago"
            if second_diff < 3600:
                return str( second_diff / 60 ) + " minutes ago"
            if second_diff < 7200:
                return "an hour ago"
            if second_diff < 86400:
                return str( second_diff / 3600 ) + " hours ago"
        if day_diff == 1:
            return "Yesterday"
        if day_diff < 7:
            return str(day_diff) + " days ago"
        if day_diff < 31:
            return str(day_diff/7) + " weeks ago"
        if day_diff < 365:
            return str(day_diff/30) + " months ago"
        return str(day_diff/365) + " years ago"
    elif d > now:
        if day_diff == 0:
            if second_diff < 10:
                return "just now"
            if second_diff < 60:
                return str(second_diff) + " seconds from now"
            if second_diff < 120:
                return  "a minute from now"
            if second_diff < 3600:
                return str( second_diff / 60 ) + " minutes from now"
            if second_diff < 7200:
                return "an hour from now"
            if second_diff < 86400:
                return str( second_diff / 3600 ) + " hours from now"
        if day_diff == 1:
            return "Tomorrow"
        if day_diff < 7:
            return str(day_diff) + " days from now"
        if day_diff < 31:
            return str(day_diff/7) + " weeks from now"
        if day_diff < 365:
            return str(day_diff/30) + " months from now"
        return str(day_diff/365) + " years from now"




######
### General functions
######


def list_of_jobs(include_completed=False,only_past_due=True):
    """ list_of_jobs()
    returns a python list of all the outstanding jobs.
    """

    query = "SELECT uuid FROM jobs"
    if include_completed == False and only_past_due == True:
        query += " WHERE completed = 0 and due <= " + str(time.time()) + ';'
    elif include_completed == False and only_past_due == False:
        query += " WHERE completed = 0;"
    elif include_completed == True and only_past_due == True:
        query += " WHERE due <= " + str(time.time()) + ';'

    jobsdb = _db()

    job_list = []    

    for row in jobsdb.query(query):
        j = Job()
        j.open(uuid=row[0])
        job_list.append(j)

    return job_list



def print_jobs(include_completed=False):
    """ print_jobs()
    list all the jobs that need to be done, does not include completed
    jobs by default.
    """

    query = 'SELECT * FROM jobs'
    if include_completed == False:
        query += ' WHERE `completed` = 0'
    query += ';'

    jobsdb = _db()

    for row in jobsdb.query(query):
        print row