def _build_filter_tree(form, prefix):
"""_build_filter_tree(form, prefix) -- returns (tree,total,errors)
Builds the subtree rooted at the prefix from the form.
tree -- filter tree structure
total -- total number of criteria
errors -- list of errors
Returns (None,0,None) if there is no subtree rooted at the prefix. Raises
a KeyError if the tree is malformed."""
try:
kind = form[prefix]
except KeyError:
return None, 0, None
if kind in ('or', 'and', 'nor', 'nand'):
prefix += '_'
subtrees, total, errors = [], 0, []
for i in itertools.count():
subprefix = prefix + str(i)
subtree, subtotal, suberr = _build_filter_tree(form, subprefix)
if subtree is None: break # There are no more subtrees.
elif subtotal == 0: continue # Skip this empty subtree.
subtrees.append(subtree)
total += subtotal
errors.extend(suberr)
return ('sub', kind, subtrees), total, errors
else:
rule = form[prefix + '_r']
if kind in ('title', 'album', 'artist'):
string = get_unicode(form, prefix + '_f0')
# If the kind is blank, then ignore the criterion.
if not string: return (), 0, ()
# Validate the rule.
if rule not in ('in', 'notin', 'start', 'notstart', 'end',
'notend', 'is', 'notis'):
raise KeyError('bad string rule: %r' % rule)
return (kind, rule, string), 1, ()
elif kind in ('time', 'track', 'play_count'):
errors = []
# Get f0 and, if needed, f1.
try:
if kind == 'time': f0 = parse_time(form[prefix + '_f0'])
else: f0 = parse_integer(form[prefix + '_f0'])
except ValueError, err:
errors.append(str(err))
if rule in ('inside', 'outside'):
try:
if kind == 'time': f1 = parse_time(form[prefix + '_f1'])
else: f1 = parse_integer(form[prefix + '_f1'])
except ValueError, err:
errors.append(str(err))
# Validate the rule.
if errors: return (), 1, errors
elif rule in ('inside', 'outside'):
return (kind, rule, (f0, f1)), 1, ()
elif rule in ('is', 'notis', 'lte', 'gte'):
return (kind, rule, f0), 1, ()
else:
raise KeyError('bad integer rule: %r' % rule)
def _build_filter_tree(form, prefix):
"""_build_filter_tree(form, prefix) -- returns (tree,total,errors)
Builds the subtree rooted at the prefix from the form.
tree -- filter tree structure
total -- total number of criteria
errors -- list of errors
Returns (None,0,None) if there is no subtree rooted at the prefix. Raises
a KeyError if the tree is malformed."""
try: kind = form[prefix]
except KeyError: return None, 0, None
if kind in ('or','and','nor','nand'):
prefix += '_'
subtrees, total, errors = [], 0, []
for i in itertools.count():
subprefix = prefix + str(i)
subtree, subtotal, suberr = _build_filter_tree(form, subprefix)
if subtree is None: break # There are no more subtrees.
elif subtotal == 0: continue # Skip this empty subtree.
subtrees.append(subtree)
total += subtotal
errors.extend(suberr)
return ('sub', kind, subtrees), total, errors
else:
rule = form[prefix+'_r']
if kind in ('title','album','artist'):
string = get_unicode(form, prefix+'_f0')
# If the kind is blank, then ignore the criterion.
if not string: return (), 0, ()
# Validate the rule.
if rule not in ('in','notin','start','notstart','end','notend',
'is','notis'):
raise KeyError('bad string rule: %r' % rule)
return (kind, rule, string), 1, ()
elif kind in ('time','track','play_count'):
errors = []
# Get f0 and, if needed, f1.
try:
if kind == 'time': f0 = parse_time(form[prefix+'_f0'])
else: f0 = parse_integer(form[prefix+'_f0'])
except ValueError, err: errors.append(str(err))
if rule in ('inside','outside'):
try:
if kind == 'time': f1 = parse_time(form[prefix+'_f1'])
else: f1 = parse_integer(form[prefix+'_f1'])
except ValueError, err: errors.append(str(err))
# Validate the rule.
if errors: return (), 1, errors
elif rule in ('inside', 'outside'):
return (kind, rule, (f0, f1)), 1, ()
elif rule in ('is','notis','lte','gte'):
return (kind, rule, f0), 1, ()
else: raise KeyError('bad integer rule: %r' % rule)
elif kind in ('date_added','last_played'):
if rule in ('last','nolast'):
# Validate the number. This is human provided, so give an
# error string if it's bad.
try: number = parse_integer(form[prefix+'_f0'])
except ValueError, err: return (), 1, (str(err),)
# Validate the unit. This is provided by the form, so raise
# a KeyError if it's bad.
unit = form[prefix+'_f1']
if unit not in ('hour','day','week','month','year'):
raise KeyError('bad date unit: %r' % unit)
return (kind, rule, (number, unit)), 1, ()
else:
errors = []
# Get f0 and, if needed, f1.
try: f0 = parse_date(form[prefix+'_f0'])
except ValueError, err: errors.append(str(err))
if rule in ('inside','outside'):
try: f1 = parse_date(form[prefix+'_f1'])
except ValueError, err: errors.append(str(err))
# Validate the rule.
if errors: return (), 1, errors
elif rule in ('before','after'):
return (kind, rule, f0), 1, ()
elif rule in ('inside','outside'):
return (kind, rule, (f0, f1)), 1, ()
else: raise KeyError('bad date rule: %r' % rule)
else: raise KeyError('bad kind: %r' % kind)
except ValueError, err:
errors.append(str(err))
# Validate the rule.
if errors: return (), 1, errors
elif rule in ('inside', 'outside'):
return (kind, rule, (f0, f1)), 1, ()
elif rule in ('is', 'notis', 'lte', 'gte'):
return (kind, rule, f0), 1, ()
else:
raise KeyError('bad integer rule: %r' % rule)
elif kind in ('date_added', 'last_played'):
if rule in ('last', 'nolast'):
# Validate the number. This is human provided, so give an
# error string if it's bad.
try:
number = parse_integer(form[prefix + '_f0'])
except ValueError, err:
return (), 1, (str(err), )
# Validate the unit. This is provided by the form, so raise
# a KeyError if it's bad.
unit = form[prefix + '_f1']
if unit not in ('hour', 'day', 'week', 'month', 'year'):
raise KeyError('bad date unit: %r' % unit)
return (kind, rule, (number, unit)), 1, ()
else:
errors = []
# Get f0 and, if needed, f1.
try:
f0 = parse_date(form[prefix + '_f0'])
except ValueError, err:
errors.append(str(err))
