## Create and compare lists of files/objects
 ## Author: Michal Ludvig <michal@logix.cz>
 ##         http://www.logix.cz/michal
 ## License: GPL Version 2
 
 from S3 import S3
 from Config import Config
 from S3Uri import S3Uri
 from SortedDict import SortedDict
 from Utils import *

 from Exceptions import ParameterError

 
 from logging import debug, info, warning, error
 
 import os
 import glob
 
 __all__ = ["fetch_local_list", "fetch_remote_list", "compare_filelists", "filter_exclude_include"]
 
 def _fswalk_follow_symlinks(path):
         '''
         Walk filesystem, following symbolic links (but without recursion), on python2.4 and later
 
         If a recursive directory link is detected, emit a warning and skip.
         '''
         assert os.path.isdir(path) # only designed for directory argument

         walkdirs = [path]

         for dirpath, dirnames, filenames in os.walk(path):
                 for dirname in dirnames:
                         current = os.path.join(dirpath, dirname)
                         if os.path.islink(current):

 				walkdirs.append(current)

         for walkdir in walkdirs:
                 for value in os.walk(walkdir):
                         yield value
 
 def _fswalk(path, follow_symlinks):
         '''
         Directory tree generator
 
         path (str) is the root of the directory tree to walk
 
         follow_symlinks (bool) indicates whether to descend into symbolically linked directories
         '''
         if follow_symlinks:
                 return _fswalk_follow_symlinks(path)
         return os.walk(path)
 
 def filter_exclude_include(src_list):

     info(u"Applying --exclude/--include")
     cfg = Config()
     exclude_list = SortedDict(ignore_case = False)
     for file in src_list.keys():
         debug(u"CHECK: %s" % file)
         excluded = False
         for r in cfg.exclude:
             if r.search(file):
                 excluded = True
                 debug(u"EXCL-MATCH: '%s'" % (cfg.debug_exclude[r]))
                 break
         if excluded:
             ## No need to check for --include if not excluded
             for r in cfg.include:
                 if r.search(file):
                     excluded = False
                     debug(u"INCL-MATCH: '%s'" % (cfg.debug_include[r]))
                     break
         if excluded:
             ## Still excluded - ok, action it
             debug(u"EXCLUDE: %s" % file)
             exclude_list[file] = src_list[file]
             del(src_list[file])
             continue
         else:
             debug(u"PASS: %s" % (file))
     return src_list, exclude_list

 
 def fetch_local_list(args, recursive = None):

     def _get_filelist_local(local_uri):
         info(u"Compiling list of local files...")
         if local_uri.isdir():
             local_base = deunicodise(local_uri.basename())
             local_path = deunicodise(local_uri.path())
             filelist = _fswalk(local_path, cfg.follow_symlinks)
             single_file = False
         else:
             local_base = ""
             local_path = deunicodise(local_uri.dirname())
             filelist = [( local_path, [], [deunicodise(local_uri.basename())] )]
             single_file = True
         loc_list = SortedDict(ignore_case = False)
         for root, dirs, files in filelist:
             rel_root = root.replace(local_path, local_base, 1)
             for f in files:
                 full_name = os.path.join(root, f)
                 if not os.path.isfile(full_name):
                     continue
                 if os.path.islink(full_name):

                                     if not cfg.follow_symlinks:
                                             continue

                 relative_file = unicodise(os.path.join(rel_root, f))
                 if os.path.sep != "/":
                     # Convert non-unix dir separators to '/'
                     relative_file = "/".join(relative_file.split(os.path.sep))
                 if cfg.urlencoding_mode == "normal":
                     relative_file = replace_nonprintables(relative_file)
                 if relative_file.startswith('./'):
                     relative_file = relative_file[2:]
                 sr = os.stat_result(os.lstat(full_name))
                 loc_list[relative_file] = {
                     'full_name_unicode' : unicodise(full_name),
                     'full_name' : full_name,
                     'size' : sr.st_size,
                     'mtime' : sr.st_mtime,
                     ## TODO: Possibly more to save here...
                 }
         return loc_list, single_file
 
     cfg = Config()
     local_uris = []
     local_list = SortedDict(ignore_case = False)
     single_file = False
 
     if type(args) not in (list, tuple):
         args = [args]
 
     if recursive == None:
         recursive = cfg.recursive
 
     for arg in args:
         uri = S3Uri(arg)
         if not uri.type == 'file':
             raise ParameterError("Expecting filename or directory instead of: %s" % arg)
         if uri.isdir() and not recursive:
             raise ParameterError("Use --recursive to upload a directory: %s" % arg)
         local_uris.append(uri)
 
     for uri in local_uris:
         list_for_uri, single_file = _get_filelist_local(uri)
         local_list.update(list_for_uri)
 
     ## Single file is True if and only if the user
     ## specified one local URI and that URI represents
     ## a FILE. Ie it is False if the URI was of a DIR
     ## and that dir contained only one FILE. That's not
     ## a case of single_file==True.
     if len(local_list) > 1:
         single_file = False
 
     return local_list, single_file

 
 def fetch_remote_list(args, require_attribs = False, recursive = None):

     def _get_filelist_remote(remote_uri, recursive = True):
         ## If remote_uri ends with '/' then all remote files will have
         ## the remote_uri prefix removed in the relative path.
         ## If, on the other hand, the remote_uri ends with something else
         ## (probably alphanumeric symbol) we'll use the last path part
         ## in the relative path.
         ##
         ## Complicated, eh? See an example:
         ## _get_filelist_remote("s3://bckt/abc/def") may yield:
         ## { 'def/file1.jpg' : {}, 'def/xyz/blah.txt' : {} }
         ## _get_filelist_remote("s3://bckt/abc/def/") will yield:
         ## { 'file1.jpg' : {}, 'xyz/blah.txt' : {} }
         ## Furthermore a prefix-magic can restrict the return list:
         ## _get_filelist_remote("s3://bckt/abc/def/x") yields:
         ## { 'xyz/blah.txt' : {} }
 
         info(u"Retrieving list of remote files for %s ..." % remote_uri)
 
         s3 = S3(Config())
         response = s3.bucket_list(remote_uri.bucket(), prefix = remote_uri.object(), recursive = recursive)
 
         rem_base_original = rem_base = remote_uri.object()
         remote_uri_original = remote_uri
         if rem_base != '' and rem_base[-1] != '/':
             rem_base = rem_base[:rem_base.rfind('/')+1]
             remote_uri = S3Uri("s3://%s/%s" % (remote_uri.bucket(), rem_base))
         rem_base_len = len(rem_base)
         rem_list = SortedDict(ignore_case = False)
         break_now = False
         for object in response['list']:
             if object['Key'] == rem_base_original and object['Key'][-1] != os.path.sep:
                 ## We asked for one file and we got that file :-)
                 key = os.path.basename(object['Key'])
                 object_uri_str = remote_uri_original.uri()
                 break_now = True
                 rem_list = {}   ## Remove whatever has already been put to rem_list
             else:
                 key = object['Key'][rem_base_len:]      ## Beware - this may be '' if object['Key']==rem_base !!
                 object_uri_str = remote_uri.uri() + key
             rem_list[key] = {
                 'size' : int(object['Size']),
                 'timestamp' : dateS3toUnix(object['LastModified']), ## Sadly it's upload time, not our lastmod time :-(
                 'md5' : object['ETag'][1:-1],
                 'object_key' : object['Key'],
                 'object_uri_str' : object_uri_str,
                 'base_uri' : remote_uri,
             }
             if break_now:
                 break
         return rem_list
 
     cfg = Config()
     remote_uris = []
     remote_list = SortedDict(ignore_case = False)
 
     if type(args) not in (list, tuple):
         args = [args]
 
     if recursive == None:
         recursive = cfg.recursive
 
     for arg in args:
         uri = S3Uri(arg)
         if not uri.type == 's3':
             raise ParameterError("Expecting S3 URI instead of '%s'" % arg)
         remote_uris.append(uri)
 
     if recursive:
         for uri in remote_uris:
             objectlist = _get_filelist_remote(uri)
             for key in objectlist:
                 remote_list[key] = objectlist[key]
     else:
         for uri in remote_uris:
             uri_str = str(uri)
             ## Wildcards used in remote URI?
             ## If yes we'll need a bucket listing...
             if uri_str.find('*') > -1 or uri_str.find('?') > -1:
                 first_wildcard = uri_str.find('*')
                 first_questionmark = uri_str.find('?')
                 if first_questionmark > -1 and first_questionmark < first_wildcard:
                     first_wildcard = first_questionmark
                 prefix = uri_str[:first_wildcard]
                 rest = uri_str[first_wildcard+1:]
                 ## Only request recursive listing if the 'rest' of the URI,
                 ## i.e. the part after first wildcard, contains '/'
                 need_recursion = rest.find('/') > -1
                 objectlist = _get_filelist_remote(S3Uri(prefix), recursive = need_recursion)
                 for key in objectlist:
                     ## Check whether the 'key' matches the requested wildcards
                     if glob.fnmatch.fnmatch(objectlist[key]['object_uri_str'], uri_str):
                         remote_list[key] = objectlist[key]
             else:
                 ## No wildcards - simply append the given URI to the list
                 key = os.path.basename(uri.object())
                 if not key:
                     raise ParameterError(u"Expecting S3 URI with a filename or --recursive: %s" % uri.uri())
                 remote_item = {
                     'base_uri': uri,
                     'object_uri_str': unicode(uri),
                     'object_key': uri.object()
                 }
                 if require_attribs:
                     response = S3(cfg).object_info(uri)
                     remote_item.update({
                     'size': int(response['headers']['content-length']),
                     'md5': response['headers']['etag'].strip('"\''),
                     'timestamp' : dateRFC822toUnix(response['headers']['date'])
                     })
                 remote_list[key] = remote_item
     return remote_list

 
 def compare_filelists(src_list, dst_list, src_remote, dst_remote):

     def __direction_str(is_remote):
         return is_remote and "remote" or "local"
 
     # We don't support local->local sync, use 'rsync' or something like that instead ;-)
     assert(not(src_remote == False and dst_remote == False))
 
     info(u"Verifying attributes...")
     cfg = Config()
     exists_list = SortedDict(ignore_case = False)
 
     debug("Comparing filelists (direction: %s -> %s)" % (__direction_str(src_remote), __direction_str(dst_remote)))
     debug("src_list.keys: %s" % src_list.keys())
     debug("dst_list.keys: %s" % dst_list.keys())
 
     for file in src_list.keys():
         debug(u"CHECK: %s" % file)
         if dst_list.has_key(file):
             ## Was --skip-existing requested?
             if cfg.skip_existing:
                 debug(u"IGNR: %s (used --skip-existing)" % (file))
                 exists_list[file] = src_list[file]
                 del(src_list[file])
                 ## Remove from destination-list, all that is left there will be deleted
                 del(dst_list[file])
                 continue
 
             attribs_match = True
             ## Check size first
             if 'size' in cfg.sync_checks and dst_list[file]['size'] != src_list[file]['size']:
                 debug(u"XFER: %s (size mismatch: src=%s dst=%s)" % (file, src_list[file]['size'], dst_list[file]['size']))
                 attribs_match = False
 

             ## Check MD5
             compare_md5 = 'md5' in cfg.sync_checks
             # Multipart-uploaded files don't have a valid MD5 sum - it ends with "...-NN"

             if compare_md5:
                 if (src_remote == True and src_list[file]['md5'].find("-") >= 0) or (dst_remote == True and dst_list[file]['md5'].find("-") >= 0):
                     compare_md5 = False
                     info(u"Disabled MD5 check for %s" % file)

             if attribs_match and compare_md5:

                 try:
                     if src_remote == False and dst_remote == True:
                         src_md5 = hash_file_md5(src_list[file]['full_name'])
                         dst_md5 = dst_list[file]['md5']
                     elif src_remote == True and dst_remote == False:
                         src_md5 = src_list[file]['md5']
                         dst_md5 = hash_file_md5(dst_list[file]['full_name'])
                     elif src_remote == True and dst_remote == True:
                         src_md5 = src_list[file]['md5']
                         dst_md5 = dst_list[file]['md5']
                 except (IOError,OSError), e:
                     # MD5 sum verification failed - ignore that file altogether
                     debug(u"IGNR: %s (disappeared)" % (file))
                     warning(u"%s: file disappeared, ignoring." % (file))
                     del(src_list[file])
                     del(dst_list[file])
                     continue
 
                 if src_md5 != dst_md5:
                     ## Checksums are different.
                     attribs_match = False
                     debug(u"XFER: %s (md5 mismatch: src=%s dst=%s)" % (file, src_md5, dst_md5))
 
             if attribs_match:
                 ## Remove from source-list, all that is left there will be transferred
                 debug(u"IGNR: %s (transfer not needed)" % file)
                 exists_list[file] = src_list[file]
                 del(src_list[file])
 
             ## Remove from destination-list, all that is left there will be deleted
             del(dst_list[file])
 
     return src_list, dst_list, exists_list
 
 # vim:et:ts=4:sts=4:ai