def __init__(self, filename):
self.filename = filename
self.treedict = TreeDict()
try:
self.treedict.load(filename)
except IOError:
self.treedict.cues = []
self.cues = self.treedict.cues
self.current_cue_index = -1
self.next_pointer = 0
self.prev_pointer = None
import atexit
atexit.register(self.save)
class CueList:
"""Persistent list of Cues"""
def __init__(self, filename):
self.filename = filename
self.treedict = TreeDict()
try:
self.treedict.load(filename)
except IOError:
self.treedict.cues = []
self.cues = self.treedict.cues
self.current_cue_index = -1
self.next_pointer = 0
self.prev_pointer = None
import atexit
atexit.register(self.save)
def add_cue(self, cue, index=None):
"""Adds a Cue object to the list. If no index is specified,
the cue will be added to the end."""
index = index or len(self.cues)
self.cues.insert(index, cue)
def shift(self, diff):
"""Shift through cue history"""
old_index = self.current_cue_index
self.current_cue_index = None
if diff < 0: # if going backwards
if self.prev_pointer: # use a prev pointer if we have one
self.current_cue_index = self.prev_pointer
self.next_pointer = old_index
self.prev_pointer = None
else:
if self.next_pointer: # use a next pointer if we have one
self.current_cue_index = self.next_pointer
self.next_pointer = None
self.prev_pointer = old_index
if not self.current_cue_index:
self.current_cue_index = old_index + diff
def set_next(self, index):
self.next_pointer = index
def set_prev(self, index):
self.prev_pointer = index
def bound_index(self, index):
if not self.cues or index < 0:
return None
else:
return min(index, len(self.cues) - 1)
def get_current_cue_indices(self):
"""Returns a list of the indices of three cues: the previous cue,
the current cue, and the next cue."""
cur = self.current_cue_index
return [self.bound_index(index) for index in
(self.prev_pointer or cur - 1,
cur,
self.next_pointer or cur + 1)]
def get_current_cues(self):
"""Returns a list of three cues: the previous cue, the current cue,
and the next cue."""
return [self.get_cue_by_index(index)
for index in self.get_current_cue_indices()]
def get_cue_by_index(self, index):
try:
return self.cues[self.bound_index(index)]
except TypeError:
return empty_cue
def __del__(self):
self.save()
def save(self, backup=0):
if backup:
backupfilename = "%s-backup" % self.filename
print time.asctime(), "Saving backup version of cues to", \
backupfilename
self.treedict.save(backupfilename)
else:
print time.asctime(), "Saving cues to", self.filename
self.treedict.save(self.filename)
def reload(self):
# TODO: we probably will need to make sure that indices still make
# sense, etc.
self.treedict.load(self.filename)
