"""distutils.dir_util



Utility functions for manipulating directories and directory trees."""



# This module should be kept compatible with Python 2.1.



__revision__ = "$Id: dir_util.py 60923 2008-02-21 18:18:37Z guido.van.rossum $"



import os, sys

from types import *

from distutils.errors import DistutilsFileError, DistutilsInternalError

from distutils import log



# cache for by mkpath() -- in addition to cheapening redundant calls,

# eliminates redundant "creating /foo/bar/baz" messages in dry-run mode

_path_created = {}



# I don't use os.makedirs because a) it's new to Python 1.5.2, and

# b) it blows up if the directory already exists (I want to silently

# succeed in that case).

def mkpath (name, mode=0777, verbose=0, dry_run=0):

    """Create a directory and any missing ancestor directories.  If the

       directory already exists (or if 'name' is the empty string, which

       means the current directory, which of course exists), then do

       nothing.  Raise DistutilsFileError if unable to create some

       directory along the way (eg. some sub-path exists, but is a file

       rather than a directory).  If 'verbose' is true, print a one-line

       summary of each mkdir to stdout.  Return the list of directories

       actually created."""



    global _path_created



    # Detect a common bug -- name is None

    if not isinstance(name, StringTypes):

        raise DistutilsInternalError, \

              "mkpath: 'name' must be a string (got %r)" % (name,)



    # XXX what's the better way to handle verbosity? print as we create

    # each directory in the path (the current behaviour), or only announce

    # the creation of the whole path? (quite easy to do the latter since

    # we're not using a recursive algorithm)



    name = os.path.normpath(name)

    created_dirs = []

    if os.path.isdir(name) or name == '':

        return created_dirs

    if _path_created.get(os.path.abspath(name)):

        return created_dirs



    (head, tail) = os.path.split(name)

    tails = [tail]                      # stack of lone dirs to create



    while head and tail and not os.path.isdir(head):

        #print "splitting '%s': " % head,

        (head, tail) = os.path.split(head)

        #print "to ('%s','%s')" % (head, tail)

        tails.insert(0, tail)          # push next higher dir onto stack



    #print "stack of tails:", tails



    # now 'head' contains the deepest directory that already exists

    # (that is, the child of 'head' in 'name' is the highest directory

    # that does *not* exist)

    for d in tails:

        #print "head = %s, d = %s: " % (head, d),

        head = os.path.join(head, d)

        abs_head = os.path.abspath(head)



        if _path_created.get(abs_head):

            continue



        log.info("creating %s", head)



        if not dry_run:

            try:

                os.mkdir(head)

                created_dirs.append(head)

            except OSError, exc:

                raise DistutilsFileError, \

                      "could not create '%s': %s" % (head, exc[-1])



        _path_created[abs_head] = 1

    return created_dirs



# mkpath ()





def create_tree (base_dir, files, mode=0777, verbose=0, dry_run=0):



    """Create all the empty directories under 'base_dir' needed to

       put 'files' there.  'base_dir' is just the a name of a directory

       which doesn't necessarily exist yet; 'files' is a list of filenames

       to be interpreted relative to 'base_dir'.  'base_dir' + the

       directory portion of every file in 'files' will be created if it

       doesn't already exist.  'mode', 'verbose' and 'dry_run' flags are as

       for 'mkpath()'."""



    # First get the list of directories to create

    need_dir = {}

    for file in files:

        need_dir[os.path.join(base_dir, os.path.dirname(file))] = 1

    need_dirs = need_dir.keys()

    need_dirs.sort()



    # Now create them

    for dir in need_dirs:

        mkpath(dir, mode, dry_run=dry_run)



# create_tree ()





def copy_tree (src, dst,

               preserve_mode=1,

               preserve_times=1,

               preserve_symlinks=0,

               update=0,

               verbose=0,

               dry_run=0):



    """Copy an entire directory tree 'src' to a new location 'dst'.  Both

       'src' and 'dst' must be directory names.  If 'src' is not a

       directory, raise DistutilsFileError.  If 'dst' does not exist, it is

       created with 'mkpath()'.  The end result of the copy is that every

       file in 'src' is copied to 'dst', and directories under 'src' are

       recursively copied to 'dst'.  Return the list of files that were

       copied or might have been copied, using their output name.  The

       return value is unaffected by 'update' or 'dry_run': it is simply

       the list of all files under 'src', with the names changed to be

       under 'dst'.



       'preserve_mode' and 'preserve_times' are the same as for

       'copy_file'; note that they only apply to regular files, not to

       directories.  If 'preserve_symlinks' is true, symlinks will be

       copied as symlinks (on platforms that support them!); otherwise

       (the default), the destination of the symlink will be copied.

       'update' and 'verbose' are the same as for 'copy_file'."""



    from distutils.file_util import copy_file



    if not dry_run and not os.path.isdir(src):

        raise DistutilsFileError, \

              "cannot copy tree '%s': not a directory" % src

    try:

        names = os.listdir(src)

    except os.error, (errno, errstr):

        if dry_run:

            names = []

        else:

            raise DistutilsFileError, \

                  "error listing files in '%s': %s" % (src, errstr)



    if not dry_run:

        mkpath(dst)



    outputs = []



    for n in names:

        src_name = os.path.join(src, n)

        dst_name = os.path.join(dst, n)



        if preserve_symlinks and os.path.islink(src_name):

            link_dest = os.readlink(src_name)

            log.info("linking %s -> %s", dst_name, link_dest)

            if not dry_run:

                os.symlink(link_dest, dst_name)

            outputs.append(dst_name)



        elif os.path.isdir(src_name):

            outputs.extend(

                copy_tree(src_name, dst_name, preserve_mode,

                          preserve_times, preserve_symlinks, update,

                          dry_run=dry_run))

        else:

            copy_file(src_name, dst_name, preserve_mode,

                      preserve_times, update, dry_run=dry_run)

            outputs.append(dst_name)



    return outputs



# copy_tree ()



# Helper for remove_tree()

def _build_cmdtuple(path, cmdtuples):

    for f in os.listdir(path):

        real_f = os.path.join(path,f)

        if os.path.isdir(real_f) and not os.path.islink(real_f):

            _build_cmdtuple(real_f, cmdtuples)

        else:

            cmdtuples.append((os.remove, real_f))

    cmdtuples.append((os.rmdir, path))





def remove_tree (directory, verbose=0, dry_run=0):

    """Recursively remove an entire directory tree.  Any errors are ignored

    (apart from being reported to stdout if 'verbose' is true).

    """

    from distutils.util import grok_environment_error

    global _path_created



    log.info("removing '%s' (and everything under it)", directory)

    if dry_run:

        return

    cmdtuples = []

    _build_cmdtuple(directory, cmdtuples)

    for cmd in cmdtuples:

        try:

            apply(cmd[0], (cmd[1],))

            # remove dir from cache if it's already there

            abspath = os.path.abspath(cmd[1])

            if abspath in _path_created:

                del _path_created[abspath]

        except (IOError, OSError), exc:

            log.warn(grok_environment_error(

                    exc, "error removing %s: " % directory))





def ensure_relative (path):

    """Take the full path 'path', and make it a relative path so

    it can be the second argument to os.path.join().

    """

    drive, path = os.path.splitdrive(path)

    if sys.platform == 'mac':

        return os.sep + path

    else:

        if path[0:1] == os.sep:

            path = drive + path[1:]

        return path

