from __future__ import division

import time, json, logging, traceback

import numpy

import serial

from twisted.internet import reactor, threads

from twisted.internet.defer import inlineCallbacks, returnValue, succeed

from twisted.internet.error import TimeoutError

from rdflib import URIRef, Literal

import cyclone.httpclient

from light9.namespaces import L9, RDF, RDFS

from light9.effecteval.effect import EffectNode

from light9 import Effects

from light9 import networking

from light9 import Submaster

from light9 import dmxclient

from light9 import prof

log = logging.getLogger('effectloop')

class EffectLoop(object):

    """maintains a collection of the current EffectNodes, gets time from

    music player, sends dmx"""

    def __init__(self, graph, stats):

        self.graph, self.stats = graph, stats

        self.currentSong = None

        self.currentEffects = []

        self.lastLogTime = 0

        self.lastLogMsg = ""

        self.lastErrorLog = 0

        self.graph.addHandler(self.setEffects)

        self.period = 1 / 30

        self.coastSecs = .3 # main reason to keep this low is to notice play/pause

        self.songTimeFetch = 0

        self.songIsPlaying = False

        self.songTimeFromRequest = 0

        self.requestTime = 0 # unix sec for when we fetched songTime

        self.initOutput()

    def initOutput(self):

        pass

    def startLoop(self):

        log.info("startLoop")

        self.lastSendLevelsTime = 0

        reactor.callLater(self.period, self.sendLevels)

        reactor.callLater(self.period, self.updateTimeFromMusic)

    def setEffects(self):

        self.currentEffects = []

        log.info('setEffects currentSong=%s', self.currentSong)

        if self.currentSong is None:

            return

        for effectUri in self.graph.objects(self.currentSong, L9['effect']):

            self.currentEffects.append(EffectNode(self.graph, effectUri))

        log.info('now we have %s effects', len(self.currentEffects))

    @inlineCallbacks

    def getSongTime(self):

        now = time.time()

        old = now - self.requestTime

        if old > self.coastSecs:

            try:

                response = json.loads((yield cyclone.httpclient.fetch(

                    networking.musicPlayer.path('time'), timeout=.5)).body)

            except TimeoutError:

                log.warning("TimeoutError: using stale time from %.1f ago", old)

            else:

                self.requestTime = now

                self.currentPlaying = response['playing']

                self.songTimeFromRequest = response['t']

                returnValue(

                    (response['t'], (response['song'] and URIRef(response['song']))))

        estimated = self.songTimeFromRequest

        if self.currentSong is not None and self.currentPlaying:

            estimated += now - self.requestTime

        returnValue((estimated, self.currentSong))

    @inlineCallbacks

    def updateTimeFromMusic(self):

        t1 = time.time()

        with self.stats.getMusic.time():

            self.songTime, song = yield self.getSongTime()

            self.songTimeFetch = time.time()

        if song != self.currentSong:

            self.currentSong = song

            # this may be piling on the handlers

            self.graph.addHandler(self.setEffects)

        elapsed = time.time() - t1

        reactor.callLater(max(0, self.period - elapsed), self.updateTimeFromMusic)

    def estimatedSongTime(self):

        now = time.time()

        t = self.songTime

        if self.currentPlaying:

            t += max(0, now - self.songTimeFetch)

        return t

    @inlineCallbacks

    def sendLevels(self):

        t1 = time.time()

        log.debug("time since last call: %.1f ms" % (1000 * (t1 - self.lastSendLevelsTime)))

        self.lastSendLevelsTime = t1

        try:

            with self.stats.sendLevels.time():

                if self.currentSong is not None:

                    with self.stats.evals.time():

                        outputs = self.allEffectOutputs(self.estimatedSongTime())

                    combined = self.combineOutputs(outputs)

                    self.logLevels(t1, combined)

                    with self.stats.sendOutput.time():

                        yield self.sendOutput(combined)

                elapsed = time.time() - t1

                dt = max(0, self.period - elapsed)

        except Exception:

            self.stats.errors += 1

            traceback.print_exc()

            dt = .5

        reactor.callLater(dt, self.sendLevels)

    def combineOutputs(self, outputs):

        """pick usable effect outputs and reduce them into one for sendOutput"""

        outputs = [x for x in outputs if isinstance(x, Submaster.Submaster)]

        out = Submaster.sub_maxes(*outputs)

        return out

    @inlineCallbacks

    def sendOutput(self, combined):

        dmx = combined.get_dmx_list()

        yield dmxclient.outputlevels(dmx, twisted=True)

    def allEffectOutputs(self, songTime):

        outputs = []

        for e in self.currentEffects:

            try:

                out = e.eval(songTime)

                if isinstance(out, (list, tuple)):

                    outputs.extend(out)

                else:

                    outputs.append(out)

            except Exception as exc:

                now = time.time()

                if now > self.lastErrorLog + 5:

                    if hasattr(exc, 'expr'):

                        log.error('in expression %r', exc.expr)

                    log.error("effect %s: %s" % (e.uri, exc))

                    self.lastErrorLog = now

        log.debug('eval %s effects, got %s outputs', len(self.currentEffects), len(outputs))

        return outputs

    def logLevels(self, now, out):

        # this would look nice on the top of the effecteval web pages too

        if log.isEnabledFor(logging.DEBUG):

            log.debug(self.logMessage(out))

        else:

            if now > self.lastLogTime + 5:

                msg = self.logMessage(out)

                if msg != self.lastLogMsg:

                    log.info(msg)

                    self.lastLogMsg = msg

                self.lastLogTime = now

    def logMessage(self, out):

        return ("send dmx: {%s}" %

                ", ".join("%r: %.3g" % (str(k), v)

                          for k,v in out.get_levels().items()))

Z = numpy.zeros((50, 3), dtype=numpy.uint8)

class LedLoop(EffectLoop):

    def initOutput(self):

        kw = dict(baudrate=115200)

        self.lastSentBacklight = None

    def combineOutputs(self, outputs):

        combined = {'L': Z, 'R': Z, 'blacklight': 0}

        for out in outputs:

            if isinstance(out, Effects.Blacklight):

                combined['blacklight'] = max(combined['blacklight'], int(out * 255))

            elif isinstance(out, Effects.Strip):

                pixels = numpy.array(out.pixels, dtype=numpy.float16)

                px255 = (numpy.clip(pixels, 0, 1) * 255).astype(numpy.uint8)

                for w in out.which:

                    combined[w] = numpy.maximum(combined[w], px255)

        return combined

    @inlineCallbacks

    def sendOutput(self, combined):

        for which, px255 in combined.items():

            if which == 'blacklight':

                if px255 != self.lastSentBacklight:

                    b = min(255, max(0, px255))

                    yield succeed(self.serialWrite(self.boards['L'],

                                                   '\x60\x01' + chr(b)))

                    self.lastSentBacklight = px255

            else:

                board = self.boards[which]

                msg = '\x60\x00' + px255.reshape((-1,)).tostring()

                # may be stuttering more, and not smoother

                #yield threads.deferToThread(self.serialWrite, board, msg)

                yield succeed(self.serialWrite(board, msg))

    def serialWrite(self, serial, msg):

        serial.write(msg)

        serial.flush()

    def logMessage(self, out):

        return str([(w, p.tolist() if isinstance(p, numpy.ndarray) else p) for w,p in out.items()])

def makeEffectLoop(graph, stats, outputWhere):

    if outputWhere == 'dmx':

        return EffectLoop(graph, stats)

    elif outputWhere == 'leds':

        return LedLoop(graph, stats)

    else:

        raise NotImplementedError("unknown output system %r" % outputWhere)