File manager

"""Convert "arbitrary" sound files to AIFF (Apple and SGI's audio format).

Input may be compressed.
Uncompressed file type may be AIFF, WAV, VOC, 8SVX, NeXT/Sun, and others.
An exception is raised if the file is not of a recognized type.
Returned filename is either the input filename or a temporary filename;
in the latter case the caller must ensure that it is removed.
Other temporary files used are removed by the function.
"""
from warnings import warnpy3k
warnpy3k("the toaiff module has been removed in Python 3.0", stacklevel=2)
del warnpy3k

import os
import tempfile
import pipes
import sndhdr

__all__ = ["error", "toaiff"]

table = {}

t = pipes.Template()
t.append('sox -t au - -t aiff -r 8000 -', '--')
table['au'] = t

# XXX The following is actually sub-optimal.
# XXX The HCOM sampling rate can be 22k, 22k/2, 22k/3 or 22k/4.
# XXX We must force the output sampling rate else the SGI won't play
# XXX files sampled at 5.5k or 7.333k; however this means that files
# XXX sampled at 11k are unnecessarily expanded.
# XXX Similar comments apply to some other file types.
t = pipes.Template()
t.append('sox -t hcom - -t aiff -r 22050 -', '--')
table['hcom'] = t

t = pipes.Template()
t.append('sox -t voc - -t aiff -r 11025 -', '--')
table['voc'] = t

t = pipes.Template()
t.append('sox -t wav - -t aiff -', '--')
table['wav'] = t

t = pipes.Template()
t.append('sox -t 8svx - -t aiff -r 16000 -', '--')
table['8svx'] = t

t = pipes.Template()
t.append('sox -t sndt - -t aiff -r 16000 -', '--')
table['sndt'] = t

t = pipes.Template()
t.append('sox -t sndr - -t aiff -r 16000 -', '--')
table['sndr'] = t

uncompress = pipes.Template()
uncompress.append('uncompress', '--')


class error(Exception):
    pass

def toaiff(filename):
    temps = []
    ret = None
    try:
        ret = _toaiff(filename, temps)
    finally:
        for temp in temps[:]:
            if temp != ret:
                try:
                    os.unlink(temp)
                except os.error:
                    pass
                temps.remove(temp)
    return ret

def _toaiff(filename, temps):
    if filename[-2:] == '.Z':
        (fd, fname) = tempfile.mkstemp()
        os.close(fd)
        temps.append(fname)
        sts = uncompress.copy(filename, fname)
        if sts:
            raise error, filename + ': uncompress failed'
    else:
        fname = filename
    try:
        ftype = sndhdr.whathdr(fname)
        if ftype:
            ftype = ftype[0] # All we're interested in
    except IOError, msg:
        if type(msg) == type(()) and len(msg) == 2 and \
                type(msg[0]) == type(0) and type(msg[1]) == type(''):
            msg = msg[1]
        if type(msg) != type(''):
            msg = repr(msg)
        raise error, filename + ': ' + msg
    if ftype == 'aiff':
        return fname
    if ftype is None or not ftype in table:
        raise error, '%s: unsupported audio file type %r' % (filename, ftype)
    (fd, temp) = tempfile.mkstemp()
    os.close(fd)
    temps.append(temp)
    sts = table[ftype].copy(fname, temp)
    if sts:
        raise error, filename + ': conversion to aiff failed'
    return temp