#!/usr/bin/env python
# ovine.py version 1.0.3
# dated 8 December 2000
# written by Julius Welby
# object oriented version of my queue manager module "rc5".
# for info see http://www.outwardlynormal.com/python/ovine.htm
#
# *** EDIT CONFIG TO USE THIS MODULE ***
# config is a tuple of tuples to hold project configuration details. Each tuple contains:
# 1) project name, 2)folder path, 3)buffer name, 4)empty size (bytes) and 5)Status: 1 = active 0 = ignore this project
# The redundancy is deliberate, as I want to preserve the generality of the script.

config = (('rc5', 'C:\Crypto', 'buff-in.rc5', 'buff-out.rc5", 8, 1), ('ogr', 'C:\Crypto', 'buff-in.ogr', 8, 0))

import os, sys, string, glob
 
class Project:
        def __init__(self):
                self.name = config[proj][0]                                     # read the configuration into the object attributes
                self.folder = config[proj][1]
                self.buffin = config[proj][2]
                self.buffout = config[proj][3]
                self.empty = config[proj][4]
                self.active = config[proj][5]
                self.statdict = {}                                              # define statdict as a dictionary
                self.file = os.path.join(self.folder, self.buffin)              # create a file attribute, the full path of the buffer
		self.buffout = 
                self.pathcheck = os.path.exists(self.file)                      # check that the file attribute is a real file
                

        # create current list of possible candidates (plus current buffer)
        def candidates(self):
                self.statdict ={}
                self.filenames = glob.glob1(self.folder, '*'+ self.buffin)      # glob.glob1 looks into the folder (arg1) for matches to arg2, returns list of matches
                self.number = len(self.filenames)                               # set self.number to the number of candidates (+ 1, the active buffer)
                for name in self.filenames:                                     # loop through the names of files in the dir
                        path = os.path.join(self.folder, name)
                        stats = os.stat(path)                                   # collect stats of candidate
                        created = stats[8]                                      # this is the last modification date
                        self.statdict[created] = path                           # add the "last mod" and "path" to the dictionary as index, value pair

        def candidate_messages(self):
                if self.number >= 2:
                        print 'Files waiting in the queue =', self.number-1
                elif self.number<=1:
                        print 'There are no candidate files waiting in the queue.'

        def promote(self):
                # identify find oldest candidate file in the list of candidates and promote it to be the new buffer
                if self.number >0:                                              # if there is at least one candidate
                        keylist = self.statdict.keys()                          # create list of last updated dates
                        smallest = min(keylist)                                 # identify smallest number (=oldest file)
                        oldest = self.statdict[smallest]                        # get the name of the oldest candidate
                        print 'Making', oldest, 'the new active buffer.'
                        os.rename(oldest, self.file)                            # rename the file to be new buffer
                        print 'New buffer created successfully.'
                        self.candidate_messages()                               # print info about queue length
                else:
                        self.candidate_messages()
                        print 'Please download new work into', self.folder + ', renaming the files appropriately.'

        def delete_file(self, file):
                print 'Removing empty file.'
                os.remove(file)                                                 # delete the file at the filepath passed in
                print 'Empty file removed.'

        def main_function(self):
                print
                print 'Project', self.name, 'is active.'
                #Does the buffer file exist?
                pathcheck = os.path.exists(self.file)
                if pathcheck:
                        #Check if file is empty
                        stats = os.stat(self.file)                                 # get the stats of the file
                        size = stats[6]                                            # extract the file size in bytes from the stats list
                        print 'There are', size, 'characters in', self.buffin      # just for info, print number of characters (bytes)
                        if size > self.empty:                                      # if there are more characters than an empty file
                                print 'The file contains work. No action required.'             # do nothing
                                self.candidates()
                                self.candidate_messages()
                        else:
                                self.delete_file(self.file)                        # delete the empty file
                                self.candidates()                                  # check for candidates
                                self.promote()                                     # run the promote function
                                
                else:                                                           # file never existed, so try to promote
                        print "There is no file called", self.buffin, "in the directory", self.folder + "."
                        self.candidates()                                       # check for candidates
                        self.promote()                                          # run the promote function
                        # Does the file exist now?
                        pathcheck = os.path.exists(self.file)
                        if pathcheck ==0:                                       # new buffer file still does not exist
                                print
                                print "If you have already downloaded work into the correct folder, you should check the script configuration settings, and the way the files have been renamed."
                                print
                        else:
                                pass

proj = 0                                                        # set project counter to 0
print
print '*'*30
for item in config:                                             # for each project entry in the config tuple
        p = Project()                                           # create instance p of class "Project"
        if p.active == 1:                                       # if active for this project
                p.main_function()                               # run the main-function
        else:
                print
                print 'Project', p.name, 'is not active.'
        proj = proj + 1