From 3846394914ec0cf423da8e0c344ef92b6ac56763 Mon Sep 17 00:00:00 2001
From: Julian Knauer <julian.knauer@de.ey.com>
Date: Thu, 2 Nov 2017 08:29:28 +0100
Subject: [PATCH] Validation of existing downloaded parts

---
 .idea/vcs.xml    |  6 +++++
 pytorrentinfo.py | 61 ++++++++++++++++++++++++++++++++++++++++++++----
 2 files changed, 62 insertions(+), 5 deletions(-)
 create mode 100644 .idea/vcs.xml

diff --git a/.idea/vcs.xml b/.idea/vcs.xml
new file mode 100644
index 0000000..94a25f7
--- /dev/null
+++ b/.idea/vcs.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="VcsDirectoryMappings">
+    <mapping directory="$PROJECT_DIR$" vcs="Git" />
+  </component>
+</project>
\ No newline at end of file
diff --git a/pytorrentinfo.py b/pytorrentinfo.py
index 3fdcbec..91ed63e 100755
--- a/pytorrentinfo.py
+++ b/pytorrentinfo.py
@@ -2,7 +2,10 @@
 
 import sys
 import os
+import os.path
 import glob
+from hashlib import sha1
+from io import BytesIO
 from torrentool.api import Torrent
 
 """
@@ -12,15 +15,28 @@ from torrentool.api import Torrent
 
 """
 
-ARG_OPTIONS = {'short': False, 'files': False}
+ARG_OPTIONS = {'short': False, 'files': False, 'existing': False, 'non-existing': False, 'validate': False}
 
 
-def parse_torrent_file(torrentfile, short_output=False, list_contents=True):
+def make_blob(buffer, fileinfo):
+    if os.path.exists(fileinfo[0]):
+        with open(fileinfo[0], 'rb') as datafd:
+            num_written = buffer.write(datafd.read())
+    else:
+        num_written = buffer.write(b'\x00' * fileinfo[1])
+    return num_written
+
+
+def parse_torrent_file(torrentfile):
+    buffer = BytesIO()
+
     torrent = Torrent.from_file(torrentfile)
     print('+- Torrent  : {}'.format(os.path.basename(torrentfile)))
     print('|  Title    : {}'.format(torrent.name))
+    info_struct = torrent._struct.get('info')
+    print('|  Piece Len: {:,} Bytes'.format(info_struct['piece length']))
     try:
-        print('|  Size     : {} bytes'.format(torrent.total_size))
+        print('|  Size     : {:,} Bytes'.format(torrent.total_size))
     except:
         print('|  Size     : {}'.format('n/a'))
     if not ARG_OPTIONS['short']:
@@ -34,9 +50,44 @@ def parse_torrent_file(torrentfile, short_output=False, list_contents=True):
         if len(torrent.webseeds) > 0:
             print('|  webseeds : {}'.format(torrent.webseeds))
         if ARG_OPTIONS['files']:
+            # TODO: move to separate print file detail method
+            num_written = 0
             for index, fileinfo in enumerate(torrent.files):
-                print('|  FILE[{:4}] name = {}'.format(index, fileinfo[0]))
-                print('|  FILE[{:4}] size = {}'.format(index, fileinfo[1]))
+                if ARG_OPTIONS['validate']:
+                    num_written += make_blob(buffer, fileinfo)
+                if ARG_OPTIONS['existing']:
+                    if os.path.exists(fileinfo[0]):
+                        print('|  FOUND   [{:4}] name = {} (size = {:,} Bytes)'.format(index, fileinfo[0], fileinfo[1]))
+                elif ARG_OPTIONS['non-existing']:
+                    print('|  MISSING [{:4}] name = {} (size = {:,} Bytes)'.format(index, fileinfo[0], fileinfo[1]))
+
+            if ARG_OPTIONS['validate']:
+                pieceshash = info_struct['pieces']
+                buffer.seek(0)
+                print('|  Validation:')
+                chunk_size = info_struct['piece length']
+                chunk = buffer.read(chunk_size)
+                chunk_hashes = []
+                while len(chunk) > 0:
+                    hashcalc = sha1()
+                    hashcalc.update(chunk)
+                    chunk_hashes.append(hashcalc.digest())
+                    chunk = buffer.read(chunk_size)
+
+                out_wrap = 0
+                completed = True
+                sys.stdout.write('|  ')
+                for digest in chunk_hashes:
+                    out_wrap += 1
+                    if digest in pieceshash:
+                        sys.stdout.write('▒')
+                    else:
+                        completed = False
+                        sys.stdout.write('░')
+                    if not(out_wrap % 64):
+                        sys.stdout.write('\n|  ')
+                sys.stdout.write('\n')
+                print('|  Completed: {}'.format(completed))
 
 
 if __name__ == '__main__':