#!/usr/bin/env python
# -*- coding: utf-8 -*-

# Author: Daniel Kahn Gillmor <dkg@fifthhorseman.net>
# License: GPLv3+

# This script reads a MIME message from stdin and produces a treelike
# representation on it stdout.

# Example:
#
# 0 dkg@alice:~$ printmimestructure < 'Maildir/cur/1269025522.M338697P12023.monkey,S=6459,W=6963:2,Sa'
# └┬╴multipart/signed 6546 bytes
#  ├─╴text/plain inline 895 bytes
#  └─╴application/pgp-signature inline [signature.asc] 836 bytes
# 0 dkg@alice:~$


# If you want to number the parts, i suggest piping the output through
# something like "cat -n"

from __future__ import print_function

import email
import sys

def print_part(z, prefix):
    fname = '' if z.get_filename() is None else ' [' + z.get_filename() + ']'
    cset = '' if z.get_charset() is None else ' (' + z.get_charset() + ')'
    disp = z.get_params(None, header='Content-Disposition')
    if (disp is None):
        disposition = ''
    else:
        disposition = ''
        for d in disp:
            if d[0] in [ 'attachment', 'inline' ]:
                disposition = ' ' + d[0]
    if z.is_multipart():
        nbytes = len(z.as_string())
    else:
        nbytes = len(z.get_payload())

    print('{}{}{}{}{} {:d} bytes'.format(
        prefix,
        z.get_content_type(),
        cset,
        disposition,
        fname,
        nbytes,
    ))

def test(z, prefix=''):
    if (z.is_multipart()):
        print_part(z, prefix+'┬╴')
        if prefix.endswith('└'):
            prefix = prefix.rpartition('└')[0] + ' '
        if prefix.endswith('├'):
            prefix = prefix.rpartition('├')[0] + '│'
        parts = z.get_payload()
        i = 0
        while (i < parts.__len__()-1):
            test(parts[i], prefix + '├')
            i += 1
        test(parts[i], prefix + '└')
        # FIXME: show epilogue?
    else:
        print_part(z, prefix+'─╴')

test(email.message_from_file(sys.stdin), '└')