import time, logging, traceback

from rdflib import URIRef
from twisted.internet import reactor
from twisted.internet.defer import inlineCallbacks, returnValue, succeed
from twisted.internet.error import TimeoutError
import numpy
import serial
import treq

from light9 import Effects
from light9 import Submaster
from light9 import dmxclient
from light9 import networking
from light9.effecteval.effect import EffectNode
from light9.namespaces import L9, RDF
from light9.metrics import metrics

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):
        self.graph = graph
        self.currentSong = None
        self.currentEffects = [
        ]  # EffectNodes for the current song plus the submaster ones
        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))

        for sub in self.graph.subjects(RDF.type, L9['Submaster']):
            for effectUri in self.graph.objects(sub, L9['drivesEffect']):
                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:
                r = yield treq.get(networking.musicPlayer.path('time'),
                                   timeout=.5)
                response = yield r.json_content()
            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 metrics('get_music').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 metrics('send_levels').time():
                if self.currentSong is not None:
                    log.debug('allEffectOutputs')
                    with metrics('evals').time():
                        outputs = self.allEffectOutputs(
                            self.estimatedSongTime())
                    log.debug('combineOutputs')
                    combined = self.combineOutputs(outputs)
                    self.logLevels(t1, combined)
                    log.debug('sendOutput')
                    with metrics('send_output').time():
                        yield self.sendOutput(combined)

                elapsed = time.time() - t1
                dt = max(0, self.period - elapsed)
        except Exception:
            metrics('errors').incr()
            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.exception('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 list(out.get_levels().items())))


Z = numpy.zeros((50, 3), dtype=numpy.float16)


class ControlBoard(object):

    def __init__(
            self,
            dev='/dev/serial/by-id/usb-FTDI_FT232R_USB_UART_A7027NYX-if00-port0'
    ):
        log.info('opening %s', dev)
        self._dev = serial.Serial(dev, baudrate=115200)

    def _8bitMessage(self, floatArray):
        px255 = (numpy.clip(floatArray, 0, 1) * 255).astype(numpy.uint8)
        return px255.reshape((-1,)).tostring()

    def setStrip(self, which, pixels):
        """
        which: 0 or 1 to pick the strip
        pixels: (50, 3) array of 0..1 floats
        """
        command = {0: '\x00', 1: '\x01'}[which]
        if pixels.shape != (50, 3):
            raise ValueError("pixels was %s" % pixels.shape)
        self._dev.write('\x60' + command + self._8bitMessage(pixels))
        self._dev.flush()

    def setUv(self, which, level):
        """
        which: 0 or 1
        level: 0 to 1
        """
        command = {0: '\x02', 1: '\x03'}[which]
        self._dev.write('\x60' + command +
                        chr(int(max(0, min(1, level)) * 255)))
        self._dev.flush()

    def setRgb(self, color):
        """
        color: (1, 3) array of 0..1 floats
        """
        if color.shape != (1, 3):
            raise ValueError("color was %s" % color.shape)
        self._dev.write('\x60\x04' + self._8bitMessage(color))
        self._dev.flush()


class LedLoop(EffectLoop):

    def initOutput(self):
        self.board = ControlBoard()
        self.lastSent = {}  # what's in arduino's memory

    def combineOutputs(self, outputs):
        combined = {
            'L': Z,
            'R': Z,
            'blacklight0': 0,
            'blacklight1': 0,
            'W': numpy.zeros((1, 3), dtype=numpy.float16)
        }

        for out in outputs:
            log.debug('combine output %r', out)

            # workaround- somehow these subs that drive fx aren't
            # sending their fx during playback (KC only), so we react
            # to the sub itself
            if isinstance(out, Submaster.Submaster) and '*' in out.name:
                level = float(out.name.split('*')[1])
                n = out.name.split('*')[0]
                if n == 'widered':
                    out = Effects.Strip.solid('LRW', (1, 0, 0)) * level
                if n == 'widegreen':
                    out = Effects.Strip.solid('LRW', (0, 1, 0)) * level
                if n == 'wideblue':
                    out = Effects.Strip.solid('LRW', (0, 0, 1)) * level
                if n == 'whiteled':
                    out = Effects.Strip.solid('LRW', (1, .7, .7)) * level
                if n == 'blacklight':
                    out = Effects.Blacklight(level)  # missing blues!

            if isinstance(out, Effects.Blacklight):
                # no picking yet
                #key = 'blacklight%s' % out.which
                for key in ['blacklight0', 'blacklight1']:
                    combined[key] = max(combined[key], out)
            elif isinstance(out, Effects.Strip):
                pixels = numpy.array(out.pixels, dtype=numpy.float16)
                for w in out.which:
                    combined[w] = numpy.maximum(
                        combined[w], pixels[:1, :] if w == 'W' else pixels)

        return combined

    @inlineCallbacks
    def sendOutput(self, combined):
        for meth, selectArgs, value in [
            ('setStrip', (0,), combined['L']),
            ('setStrip', (1,), combined['R']),
            ('setUv', (0,), combined['blacklight0']),
            ('setUv', (1,), combined['blacklight1']),
            ('setRgb', (), combined['W']),
        ]:
            key = (meth, selectArgs)
            compValue = value.tolist() if isinstance(value,
                                                     numpy.ndarray) else value

            if self.lastSent.get(key) == compValue:
                continue

            log.debug('value changed: %s(%s %s)', meth, selectArgs, value)

            getattr(self.board, meth)(*(selectArgs + (value,)))
            self.lastSent[key] = compValue

        yield succeed(None)  # there was an attempt at an async send

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


def makeEffectLoop(graph, outputWhere):
    if outputWhere == 'dmx':
        return EffectLoop(graph)
    elif outputWhere == 'leds':
        return LedLoop(graph)
    else:
        raise NotImplementedError("unknown output system %r" % outputWhere)