from TLUtility import make_attributes_from_args, dict_scale, dict_max, \
    DummyClass, last_less_than, first_greater_than
from time import time
import random
from __future__ import division # "I'm sending you back to future!"

"""
Quote of the Build (from Ghostbusters II)
Dana:  Okay, but after dinner, I don't want you putting any of your old cheap 
       moves on me. 
Peter: Ohhhh no! I've got all NEW cheap moves.
"""

class MissingBlender(Exception):
    """Raised when a TimedEvent is missing a blender."""
    def __init__(self, timedevent):
        make_attributes_from_args('timedevent')
        Exception.__init__(self, "%r is missing a blender." % \
            self.timedevent)

# these are chosen so we can multiply by -1 to reverse the direction,
# and multiply direction by the time difference to determine new times.
FORWARD = 1
BACKWARD = -1

MISSING = 'missing'

class TimedEvent:
    """Container for a Frame which includes a time that it occurs at,
    and which blender occurs after it."""
    def __init__(self, time, frame=MISSING, blender=None, level=1.0):
        make_attributes_from_args('time', 'frame')
        self.next_blender = blender
        self.level = level
    def __float__(self):
        return self.time
    def __cmp__(self, other):
        if other is None:
            raise "I can't compare with a None.  I am '%s'" % str(self)
        if type(other) in (float, int):
            return cmp(self.time, other)
        else:
            return cmp(self.time, other.time)
    def __repr__(self):
        return "<TimedEvent %s at %.2f, time=%.2f, next blender=%s>" % \
            (self.frame, self.level, self.time, self.next_blender)
    def get_level(self):
        return self.level
    def __hash__(self):
        return id(self.time) ^ id(self.frame) ^ id(self.next_blender)

class Blender:
    """Blenders are functions that merge the effects of two LevelFrames."""
    def __init__(self):
        pass
    def __call__(self, startframe, endframe, blendtime,  time_since_startframe):
        """Return a LevelFrame combining two LevelFrames (startframe and 
        endframe).  blendtime is how much of the blend should be performed
        and will be expressed as a percentage divided by 100, i.e. a float
        between 0.0 and 1.0.  time_since_startframe is the time since the
        startframe was on screen in seconds (float).
        
        Very important note: Blenders will *not* be asked for values
        at end points (i.e. blendtime=0.0 and blendtime=1.0).
        The LevelFrames will be allowed to specify the values at
        those times.  This is unfortunately for implemementation and
        simplicity purposes.  In other words, if we didn't do this,
        we could have two blenders covering the same point in time and
        not know which one to ask for the value.  Thus, this saves us
        a lot of messiness with minimal or no sacrifice."""
        pass
    def __str__(self):
        """As a default, we'll just return the name of the class.  Subclasses
        can add parameters on if they want."""
        return str(self.__class__)
    def linear_blend(self, startframe, endframe, blendtime):
        """Utility function to help you produce linear combinations of two
        blends.  blendtime is the percent/100 that the blend should 
        completed.  In other words, 0.25 means it should be 0.75 * startframe +
        0.25 * endframe.  This function is included since many blenders are
        just functions on the percentage and still combine start and end frames
        in this way."""
        if startframe.frame == endframe.frame:
            level = startframe.level + (blendtime * \
                (endframe.level - startframe.level))
            levels = {startframe.frame : level}
        else:
            levels = {startframe.frame : (1.0 - blendtime) * startframe.level,
                endframe.frame : blendtime * endframe.level}
        return levels

class InstantEnd(Blender):
    """Instant change from startframe to endframe at the end.  In other words,
    the value returned will be the startframe all the way until the very end
    of the blend."""
    def __call__(self, startframe, endframe, blendtime, time_since_startframe):
        # "What!?" you say, "Why don't you care about blendtime?"
        # This is because Blenders never be asked for blenders at the endpoints
        # (after all, they wouldn't be blenders if they were). Please see
        # 'Very important note' in Blender.__doc__
        return {startframe.frame : startframe.level}

class InstantStart(Blender):
    """Instant change from startframe to endframe at the beginning.  In other
    words, the value returned will be the startframe at the very beginning
    and then be endframe at all times afterwards."""
    def __call__(self, startframe, endframe, blendtime, time_since_startframe):
        # "What!?" you say, "Why don't you care about blendtime?"
        # This is because Blenders never be asked for blenders at the endpoints
        # (after all, they wouldn't be blenders if they were). Please see
        # 'Very important note' in Blender.__doc__
        return {endframe.frame : endframe.level}

class LinearBlender(Blender):
    """Linear fade from one frame to another"""
    def __call__(self, startframe, endframe, blendtime, time_since_startframe):
        return self.linear_blend(startframe, endframe, blendtime)

class ExponentialBlender(Blender):
    """Exponential fade fron one frame to another.  You get to specify
    the exponent.  If my math is correct, exponent=1 means the same thing
    as LinearBlender."""
    def __init__(self, exponent):
        self.exponent = exponent
    def __call__(self, startframe, endframe, blendtime, time_since_startframe):
        blendtime = blendtime ** self.exponent
        return self.linear_blend(startframe, endframe, blendtime)

# 17:02:53 drewp: this makes a big difference for the SmoothBlender 
#                 (-x*x*(x-1.5)*2) function
class SmoothBlender(Blender):
    """Drew's "Smoove" Blender function.  Hopefully he'll document and
    parametrize it."""
    def __call__(self, startframe, endframe, blendtime, time_since_startframe):
        blendtime = (-1 * blendtime) * blendtime * (blendtime - 1.5) * 2
        return self.linear_blend(startframe, endframe, blendtime)

class Strobe(Blender):
    "Strobes the frame on the right side between offlevel and onlevel."
    def __init__(self, ontime, offtime, onlevel=1, offlevel=0):
        "times are in seconds (floats)"
        make_attributes_from_args('ontime', 'offtime', 'onlevel', 'offlevel')
        self.cycletime = ontime + offtime
    def __call__(self, startframe, endframe, blendtime, time_since_startframe):
        # time into the current period
        period_time = time_since_startframe % self.cycletime
        if period_time <= self.ontime:
            return {endframe.frame : self.onlevel}
        else:
            return {endframe.frame : self.offlevel}

class Sine(Blender):
    "Strobes the frame on the right side between offlevel and onlevel."
    def __init__(self, period, onlevel=1, offlevel=0):
        "times are in seconds (floats)"
        make_attributes_from_args('period', 'onlevel', 'offlevel')
    def __call__(self, startframe, endframe, blendtime, time_since_startframe):
        sin = math.sin(time_since_startframe / self.period * 2 * math.pi)
        zerotoone = (sin / 2) + 0.5
        level = offlevel + (zerotoone * (onlevel - offlevel))
        return {endframe.frame : level}

class RandomStrobe(Blender):
    def __init__(self, minwaitlen=0.1, maxwaitlen=0.6, burstlen=0.14, \
        burstintensity=1, offintensity=0.05, tracklen=500):
        "times are in seconds (floats)"
        make_attributes_from_args('burstlen', 'burstintensity', 'offintensity')
        self.burstintervals = []
        timecursor = 0

        while timecursor < tracklen:
            waitlen = minwaitlen + (random.random() * (maxwaitlen - minwaitlen))
            timecursor += waitlen
            self.burstintervals.append((timecursor, timecursor + burstlen))
    def __call__(self, startframe, endframe, blendtime, time_since_startframe):
        found_burst = 0
        for intstart, intend in self.burstintervals:
            if intstart <= time_since_startframe <= intend:
                found_burst = 1
                break

        if found_burst:
            return {endframe.frame : self.burstintensity}
        else:
            return {endframe.frame : self.offintensity}

class TimelineTrack:
    """TimelineTrack is a single track in a Timeline.  It consists of a
    list of TimedEvents and a name.  Length is automatically the location
    of the last TimedEvent.  To extend the Timeline past that, add an
    EmptyTimedEvent (which doesn't exist :-/)."""
    def __init__(self, name, *timedevents, **kw):
        if kw.get('default_frame'):
            self.default_frame = kw['default_frame']
        else:
            self.default_frame = None
        self.name = name
        self.set_events(list(timedevents))
    def set_events(self, events):
        """This is given a list of TimedEvents.  They need not be sorted."""
        self.events = events
        self._cleaup_events()
    def _cleaup_events(self):
        """This makes sure all events are in the right order and have defaults
        filled in if they have missing frames."""
        self.events.sort()
        self.fill_in_missing_frames()
    def add_event(self, event):
        """Add a TimedEvent object to this TimelineTrack"""
        self.events.append(event)
        self._cleaup_events(self.events)
    def delete_event(self, event):
        """Delete event by TimedEvent object"""
        self.events.remove(event)
        self._cleaup_events(self.events)
    def delete_event_by_name(self, name):
        """Deletes all events matching a certain name"""
        self.events = [e for e in self.events if e.name is not name]
        self._cleaup_events(self.events)
    def delete_event_by_time(self, starttime, endtime=None):
        """Deletes all events within a certain time range, inclusive.  endtime
        is optional."""
        endtime = endtime or starttime
        self.events = [e for e in self.events
            if e.time >= starttime and e.time <= endtime]
        self._cleaup_events(self.events)
    def fill_in_missing_frames(self):
        """Runs through all events and sets TimedEvent with missing frames to
        the default frame."""
        for event in self.events:
            if event.frame == MISSING:
                event.frame = self.default_frame
    def __str__(self):
        return "<TimelineTrack with events: %r>" % self.events
    def has_events(self):
        """Whether the TimelineTrack has anything in it.  In general,
        empty level Tracks should be avoided.  However, empty function tracks
        might be common."""
        return len(self.events)
    def length(self):
        """Returns the length of this track in pseudosecond time units.
        This is done by finding the position of the last TimedEvent."""
        return float(self.events[-1])
    def get(self, key, direction=FORWARD):
        """Returns the event at a specific time key.  If there is no event
        at that time, a search will be performed in direction.  Also note
        that if there are multiple events at one time, only the first will
        be returned.  (Probably first in order of adding.)  This is not
        a problem at the present since this method is intended for LevelFrames,
        which must exist at unique times."""
        if direction == BACKWARD:
            func = last_less_than
        else:
            func = first_greater_than

        return func(self.events, key)
    def get_range(self, i, j, direction=FORWARD):
        """Returns all events between i and j, exclusively.  If direction
        is FORWARD, j will be included.  If direction is BACKWARD, i will
        be included.  This is because this is used to find FunctionFrames
        and we assume that any function frames at the start point (which
        could be i or j) have been processed."""
        return [e for e in self.events if e >= i and e <= j]

        if direction == FORWARD:
            return [e for e in self.events if e > i and e <= j]
        else:
            return [e for e in self.events if e >= i and e < j]
    def __getitem__(self, key):
        """Returns the event at or after a specific time key.
        For example: timeline[3] will get the first event at time 3.

        If you want to get all events at time 3, you are in trouble, but
        you could achieve it with something like: 
        timeline.get_range(2.99, 3.01, FORWARD) 
        This is hopefully a bogus problem, since you can't have multiple
        LevelFrames at the same time."""
        return self.get(key, direction=FORWARD)
    def get_surrounding_frames(self, time):
        """Returns frames before and after a specific time.  This returns
        a 2-tuple: (previousframe, nextframe).  If you have chosen the exact 
        time of a frame, it will be both previousframe and nextframe."""
        return self.get(time, direction=BACKWARD), \
               self.get(time, direction=FORWARD)
    def get_levels_at_time(self, time):
        """Returns a LevelFrame with the levels of this track at that time."""
        before, after = self.get_surrounding_frames(time)
        
        if not after or before == after:
            return {before.frame : before.level}
        else: # we have a blended value
            diff = after.time - before.time
            elapsed = time - before.time
            percent = elapsed / diff
            if not before.next_blender:
                raise MissingBlender, before
            return before.next_blender(before, after, percent, elapsed)

class Timeline:
    def __init__(self, name, tracks, rate=1, direction=FORWARD):
        """
        Most/all of this is old:

        You can have multiple FunctionFrames at the same time.  Their
        order is important though, since FunctionFrames will be applied
        in the order seen in this list.  blenders is a list of Blenders.
        rate is the rate of playback.  If set to 1, 1 unit inside the
        Timeline will be 1 second.  direction is the initial direction.
        If you want to do have looping, place a LoopFunction at the end of
        the Timeline.  Timelines don't have a set length.  Their length
        is bounded by their last frame.  You can put an EmptyFrame at
        some time if you want to extend a Timeline."""
        
        make_attributes_from_args('name', 'tracks', 'rate', 'direction')
        self.current_time = 0
        self.last_clock_time = None
        self.stopped = 1
    def length(self):
        """Length of the timeline in pseudoseconds.  This is determined by
        finding the length of the longest track."""
        track_lengths = [track.length() for track in self.tracks]
        return max(track_lengths)
    def play(self):
        """Activates the timeline.  Future calls to tick() will advance the 
        timeline in the appropriate direction."""
        self.stopped = 0
    def stop(self):
        """The timeline will no longer continue in either direction, no
        FunctionFrames will be activated."""
        self.stopped = 1
        self.last_clock_time = None
    def reset(self):
        """Resets the timeline to 0.  Does not change the stoppedness of the 
        timeline."""
        self.current_time = 0
    def tick(self):
        """Updates the current_time and runs any FunctionFrames that the cursor
        passed over.  This call is ignored if the timeline is stopped."""
        if self.stopped:
            return
        
        last_time = self.current_time
        last_clock = self.last_clock_time
        
        # first, determine new time
        clock_time = time()
        if last_clock is None:
            last_clock = clock_time
        diff = clock_time - last_clock
        new_time = (self.direction * self.rate * diff) + last_time
        
        # update the time
        self.last_clock_time = clock_time
        self.current_time = new_time
        
        # now we make sure we're in bounds (we don't do this before, since it
        # can cause us to skip events that are at boundaries.
        self.current_time = max(self.current_time, 0)
        self.current_time = min(self.current_time, self.length())
    def reverse_direction(self):
        """Reverses the direction of play for this node"""
        self.direction = self.direction * -1
    def set_direction(self, direction):
        """Sets the direction of playback."""
        self.direction = direction
    def set_rate(self, new_rate):
        """Sets the rate of playback"""
        self.rate = new_rate
    def set_time(self, new_time):
        """Set the time to a new time."""
        self.current_time = new_time
    def get_levels(self):
        """Return the current levels from this timeline.  This is done by
        adding all the non-functional tracks together."""
        levels = [t.get_levels_at_time(self.current_time)
                    for t in self.tracks]
        return dict_max(*levels)

if __name__ == '__main__':
    def T(*args, **kw):
        """This used to be a synonym for TimedEvent:

        T = TimedEvent

        It now acts the same way, except that it will fill in a default 
        blender if you don't.  The default blender is a LinearBlender."""
        linear = LinearBlender()
        if 'blender' not in kw:
            kw['blender'] = linear

        return TimedEvent(*args, **kw)

    quad = ExponentialBlender(2)
    invquad = ExponentialBlender(0.5)
    smoove = SmoothBlender()

    track1 = TimelineTrack('red track',
        T(0, 'red', level=0),
        T(4, 'red', blender=quad, level=0.5),
        T(12, 'red', blender=smoove, level=0.7),
        T(15, 'red', level=0.0)) # last TimedEvent doesn't need a blender
    track2 = TimelineTrack('green track',
        T(0, 'green', blender=invquad, level=0.2),
        T(5, 'green', blender=smoove, level=1),
        T(10, 'green', level=0.8),
        T(15, 'green', level=0.6),
        T(20, 'green', level=0.0)) # last TimedEvent doesn't need a blender
    track3 = TimelineTrack('tableau demo',
        T(0, 'blue', level=0.0),
        T(2, 'blue', level=1.0, blender=InstantEnd()),
        T(18, 'blue', level=1.0),
        T(20, 'blue', level=0.0))

    tl = Timeline('test', [track1, track2, track3])

    tl.play()

    import Tix
    root = Tix.Tk()
    colorscalesframe = Tix.Frame(root)
    scalevars = {}
    # wow, this works out so well, it's almost like I planned it!
    # (actually, it's probably just Tk being as cool as it usually is)
    # ps. if this code ever turns into mainstream code for flax, I'll be
    # pissed (reason: we need to use classes, not this hacked crap!)
    colors = 'red', 'blue', 'green', 'yellow', 'purple'
    for color in colors:
        sv = Tix.DoubleVar()
        scalevars[color] = sv
        scale = Tix.Scale(colorscalesframe, from_=1, to_=0, res=0.01, bg=color,
            variable=sv)
        scale.pack(side=Tix.LEFT)

    def set_timeline_time(time):
        tl.set_time(float(time))
        # print 'set_timeline_time', time

    def update_scales():
        levels = tl.get_levels()
        for color in colors:
            scalevars[color].set(levels.get(color, 0))
    
    colorscalesframe.pack()
    time_scale = Tix.Scale(root, from_=0, to_=tl.length(), 
        orient=Tix.HORIZONTAL, res=0.01, command=set_timeline_time)
    time_scale.pack(side=Tix.BOTTOM, fill=Tix.X, expand=1)

    def play_tl():
        tl.tick()
        update_scales()
        time_scale.set(tl.current_time)
        # print 'time_scale.set', tl.current_time
        root.after(10, play_tl)
    
    controlwindow = Tix.Toplevel()
    Tix.Button(controlwindow, text='Stop', 
        command=lambda: tl.stop()).pack(side=Tix.LEFT)
    Tix.Button(controlwindow, text='Play', 
        command=lambda: tl.play()).pack(side=Tix.LEFT)
    Tix.Button(controlwindow, text='Reset', 
        command=lambda: time_scale.set(0)).pack(side=Tix.LEFT)
    Tix.Button(controlwindow, text='Flip directions', 
        command=lambda: tl.reverse_direction()).pack(side=Tix.LEFT)
    Tix.Button(controlwindow, text='1/2x', 
        command=lambda: tl.set_rate(0.5 * tl.rate)).pack(side=Tix.LEFT)
    Tix.Button(controlwindow, text='2x', 
        command=lambda: tl.set_rate(2 * tl.rate)).pack(side=Tix.LEFT)
    
    root.after(100, play_tl)

    # Timeline.set_time = trace(Timeline.set_time)
        
    Tix.mainloop()