#!/usr/bin/env python
# vim:ts=4:sw=4:expandtab:ft=python:fileencoding=utf-8

"""
SYNOPSIS

    twit [-h] [-v,--verbose] [--version] [-u,--username] [-p,--password]
        [-r,--reject_oversize] "Status message to send"

DESCRIPTION

    This is a simple Twitter client. It sends status messages to Twitter. It
    can read status messages from a stdin pipe-line or as arguments on the
    command-line. If there is both then the arguments will be appended to whatever
    is read from stdin.

    Do not update more than once a second without getting permission from
    Twitter. Otherwise they will automatically block your updates.

    The username and password can be stored in environment variables; passed on
    the command-line; or prompted for interactively. If you store your username and
    password in environment variables then do something like this:

        export twit_username=my_username
        export twit_password=my_password

EXAMPLES

    This is a simple example of how to use this script:

        twit -u my_username -p my_password This is a test status message.

    This will prompt you for your password:

        twit -u my_username This is a test status message.

    This will prompt you for both your username and your password (unless
    set in environment variables):

        twit This is a test status message.

    This accepts text from a stdin pipeline. Here I echo a status message into the script:

        echo "Hello test status message" | twit -u my_username -p my_password

    Note that by default `twit` will silently truncate your message at 140
    characters. If you want to use this in a situation were you would rather catch
    and report oversized message, then you can specify the -r option. With the -r
    option `twit` will not send the message and will return with an exit code of 1.
    For example, this will be rejected:

        twit -r -u my_username -p my_password This message is over 140
            characters in length. It will be rejected and an exit code of 1 will be
            returned to the caller instead of the usual 0 exit code for success.

EXIT STATUS

    Exits with 0 if there were no errors. Exits with 1 if the status message
    could not be posted to Twitter.

AUTHOR

    Noah Spurrier <noah@noah.org>

LICENSE

    This script is in the public domain, free from copyrights or restrictions.

VERSION

    $Id: twit 261 2008-05-22 19:11:57Z noah $
"""

import sys, os, traceback, optparse, getpass, time
import urllib, urllib2

def update (username, password, status):

    """This sends the status update to Twitter with the given username and
    password. This authenticates with Basic Auth. Note: Do not update more
    than once a second without getting permission from Twitter."""

    uri = "http://twitter.com/statuses/update.json"
    auth_handler = urllib2.HTTPBasicAuthHandler()
    auth_handler.add_password("Twitter API", uri, username, password)
    req = urllib2.build_opener(auth_handler)
    opts = urllib.urlencode({"status":status, "source":"twit" })
    try:
        req.open(uri, opts).read()
    except urllib2.HTTPError, e:
        print str(e)
        print "Could not update twitter status."
        return 1
    return 0

def main ():

    global options, args

    username = None
    password = None
    if 'twit_username' in os.environ:
        username = os.environ['twit_username']
    if 'twit_password' in os.environ:
        password = os.environ['twit_password']
    if options.username is not None:
        username = options.username
    if options.password is not None:
        password = options.password
    if username is None:
        username = raw_input('username: ')
    if password is None:
        password = getpass.getpass('password: ')

    status = ''
    if not sys.stdin.isatty(): # process stdin pipeline
        status=sys.stdin.read()
    status = status + ' '.join(args)

    if options.reject_oversize and len(status)>140:
        print "Rejecting oversized status message!",
        print "Status message length:", len(status)
        return 1
    status = status[:140]
    if options.verbose:
        print "username:", username
        print "password:", password
        print "status:", status
    if options.test:
        return 0
    return update(username, password, status)

if __name__ == '__main__':
    try:
        start_time = time.time()
        parser = optparse.OptionParser(formatter=optparse.TitledHelpFormatter(), usage=globals()['__doc__'], version='$Id: twit 261 2008-05-22 19:11:57Z noah $')
        parser.add_option ('-v', '--verbose', action='store_true', default=False, help='verbose output')
        parser.add_option ('-u', '--username', default=None, help='Your Twitter username')
        parser.add_option ('-p', '--password', default=None, help='Your Twitter password')
        parser.add_option ('-r', '--reject_oversize', action='store_true', default=False, help='Reject oversize status messages.')
        parser.add_option ('-t', '--test', action='store_true', default=False, help='test mode (does not connect)')
        (options, args) = parser.parse_args()
        if options.verbose: print time.asctime()
        exit_code = main()
        if options.verbose: print time.asctime()
        if options.verbose: print 'TOTAL TIME IN MINUTES:',
        if options.verbose: print (time.time() - start_time) / 60.0
        sys.exit(exit_code)
    except KeyboardInterrupt, e: # Ctrl-C
        raise e
    except SystemExit, e: # sys.exit()
        raise e
    except Exception, e:
        print 'ERROR, UNEXPECTED EXCEPTION'
        print str(e)
        traceback.print_exc()
        os._exit(1)