expunge

#!/usr/bin/python

import logging
import optparse
import os
import sys

import libdelete

header = "The following deleted files are going to be expunged:\n"
footer = """
The above files, which have been marked for deletion, are about to be
expunged forever!  Make sure you don't need any of them before continuing.
"""
confirmation = "Do you wish to continue [return = no]? "

logger = logging.getLogger('expunge')
whoami = os.path.basename(sys.argv[0])

def debug_callback(option, opt_str, value, parser):
    """
    An OptionParser callback that enables debugging.
    """
    all_loggers = [logger.name, 'libdelete']
    loggers = [x.strip() for x in value.split(',')]
    if value.lower() == 'all':
        loggers = all_loggers
    else:
        if not set(loggers) == set(all_loggers):
            parser.error('Valid debug targets: {0}'.format(
                    ", ".join(all_loggers)))
    for l in loggers:
        logging.getLogger(l).setLevel(logging.DEBUG)

def ask(question, *args, **kwargs):
    """
    Ask a question, possibly prepended with the name of the program
    and determine whether the user answered in the affirmative
    """
    yes = ('y', 'yes')
    prepend = '' if kwargs.get('nowhoami', False) else "{0}: ".format(whoami)
    try:
        return raw_input("%s%s " % (prepend,
                                    question % args)).strip().lower() in yes
    except KeyboardInterrupt:
        sys.exit(0)

def perror(message, **kwargs):
    """
    Format an error message, log it in the debug log
    and maybe also print it to stderr.
    """
    should_print = not kwargs.pop('_maybe', False)
    msg = "{0}: {1}".format(whoami, message.format(**kwargs))
    logger.debug("Error: %s", msg)
    if should_print:
        print >>sys.stderr, msg

def getsize(path):
    size = os.path.getsize(path)
    return (size, "(%dKB)" % (libdelete.to_kb(size),))

def expunge(deleted_files, options):
    expunged_size = 0
    errors = 0
    if options.listfiles:
        print header
        print libdelete.format_columns(sorted(
                [libdelete.relpath(
                        libdelete.undeleted_name(x)) for x in deleted_files]))
        print footer
        if not options.force and \
                not ask(confirmation, nowhoami=True):
            logger.debug("User failed to confirm; exiting")
            sys.exit(0)
    for f in deleted_files:
        logger.debug("Processing %s", f)
        real_name = libdelete.relpath(libdelete.undeleted_name(f))
        logger.debug("Undeleted name: %s", real_name)
        if options.interactive or options.yieldsize or options.verbose:
            size, size_str = (0, '(??KB)')
            try:
                size, size_str = getsize(f)
            except OSError as e:
                perror('{filename}: {error} while getting size',
                       filename=e.filename, error=e.strerror)
                errors = 1
            logger.debug("Size, size_str = %s, %s", size, size_str)
            expunged_size += size
            if options.interactive:
                filetype = 'directory' if os.path.isdir(f) else ''
                # This is correct.  We do not display sizes of directories
                # when prompting, but do display them below.  Because why not.
                if not ask('Expunge %s%s%s?', filetype, real_name,
                           '' if os.path.isdir(f) else size_str):
                    logger.debug("User failed to confirm, exiting...")
                    # We exit here, not keep going, as the original code did
                    sys.exit(errors)
            if options.verbose:
                print "{whoami}: {path} {size} {maybe}expunged ({total}KB total)".format(whoami=whoami, path=f, size=size_str, maybe='would be ' if options.noop else '', total=libdelete.to_kb(expunged_size))
        if not options.noop:
            if os.path.isdir(f) and not os.path.islink(f):
                logger.debug("rmdir: %s", f)
                os.rmdir(f)
            else:
                logger.debug("unlink: %s", f)
                os.unlink(f)

    if options.yieldsize:
        print "Total expunged: {0}KB".format(libdelete.to_kb(expunged_size))
    return errors

def parse_options():
    parser = optparse.OptionParser(usage="%prog [options] filename ...")
    parser.add_option(
        "-l", dest="listfiles", action="store_true", default=False,
        help="List files before expunging")
    parser.add_option(
        "-r", dest="recursive", action="store_true", default=False,
        help="Recursively delete non-empty directories")
    parser.add_option(
        "-f", dest="force", action="store_true", default=False,
        help="Do not ask questions or report errors about nonexistent files")
    parser.add_option(
        "-i", dest="interactive", action="store_true", default=False,
        help="Prompt for confirmation before deleting each file/directory")
    parser.add_option(
        "-n", dest="noop", action="store_true", default=False,
        help="Don't actually delete, just print what would be deleted")
    parser.add_option(
        "-v", dest="verbose", action="store_true", default=False,
        help="Print each filename as it is deleted")
    parser.add_option(
        "-t", dest="timev", action="store", type="int", default=0,
        help="Only list n-day-or-older files", metavar="n")
    parser.add_option(
        "-y", dest="yieldsize", action="store_true", default=False,
        help="Report total space taken up by files")
    parser.add_option(
        "-s", dest="f_links", action="store_true", default=False,
        help="Follow symlinks to directories")
    parser.add_option(
        "-m", dest="f_mounts", action="store_true", default=False,
        help="Follow mount points")
    parser.add_option(
        "--debug", action="callback", type='string', help="Enable debugging (logger target or 'all')",
        callback=debug_callback, metavar='target')
    (options, args) = parser.parse_args()
    if options.noop:
        # -n implies -v
        options.verbose = True
    return (options, args)

def main():
    rv = 0
    if ((whoami == "purge") and len(sys.argv) > 1):
        if (len(sys.argv) == 2) and (sys.argv[1] == '--debug'):
            sys.argv.append('all')
        else:
            print >>sys.stderr, "purge does not take any arguments or options."
            sys.exit(1)
    (options, args) = parse_options()
    if (whoami == "purge"):
        args = [os.path.expanduser('~')]
        options.recursive = True
        options.listfiles = True
    if len(args) < 1:
        args.append('.')
    deleted_files = []
    for filename in args:
        try:
            deleted_files += libdelete.find_deleted_files(
                filename,
                follow_links=options.f_links,
                follow_mounts=options.f_mounts,
                recurse_undeleted_subdirs=options.recursive or None,
                recurse_deleted_subdirs=True,
                n_days=options.timev)
        except libdelete.DeleteError as e:
            perror(e.message)
            rv = 1
        logger.debug("Found %d files", len(deleted_files))
        if len(deleted_files):
            # Sort them so we're deleting leaves first
            # Doesn't cover all corner cases, but covers everything the old
            # code supported.  In particular, weird symlinks will make this
            # sad
            deleted_files.sort(reverse=True, key=lambda x: x.count(os.path.sep))
            rv += expunge(deleted_files, options)

    return rv

if __name__ == "__main__":
    logging.basicConfig(level=logging.WARNING)
    sys.exit(main())