# -*- coding: utf-8 -*-
#Copyright (c) 2007-8, Playful Invention Company.
#Copyright (c) 2008-10, Walter Bender
#Copyright (c) 2008-10, Raúl Gutiérrez Segalés

#Permission is hereby granted, free of charge, to any person obtaining a copy
#of this software and associated documentation files (the "Software"), to deal
#in the Software without restriction, including without limitation the rights
#to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
#copies of the Software, and to permit persons to whom the Software is
#furnished to do so, subject to the following conditions:

#The above copyright notice and this permission notice shall be included in
#all copies or substantial portions of the Software.

#THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
#IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
#FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
#AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
#LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
#OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
#THE SOFTWARE.

import gtk

from time import time
from math import sqrt
from numpy import append
from numpy.fft import rfft
from random import uniform
from operator import isNumberType
from fcntl import ioctl
import v4l2
import os.path

from UserDict import UserDict

try:
    from sugar.datastore import datastore
except ImportError:
    pass

from taconstants import TAB_LAYER, BLACK, WHITE, \
    DEFAULT_SCALE, ICON_SIZE, BLOCK_NAMES, CONSTANTS, SENSOR_DC_NO_BIAS, \
    SENSOR_DC_BIAS, XO1, XO15
from tajail import myfunc, myfunc_import
from tautils import get_pixbuf_from_journal, convert, data_from_file, \
    text_media_type, round_int, chr_to_ord, strtype, get_path

from RtfParser import RtfTextOnly

from ringbuffer import RingBuffer1d

from gettext import gettext as _

VALUE_BLOCKS = ['box1', 'box2', 'color', 'shade', 'gray', 'scale', 'pensize',
                'heading', 'xcor', 'ycor', 'pop', 'see', 'keyboard',
                'sound', 'volume', 'pitch', 'resistance', 'voltage',
                'luminance', 'time']

import logging
_logger = logging.getLogger('turtleart-activity')


def find_device():
    """ Search for RFID devices. Return a device instance or None. """
    device = None
    for i in os.listdir(os.path.join('.', 'devices')):
        if not os.path.isdir(os.path.join('.', 'devices', i)):
            try:
                _tempmod = __import__('devices.%s' % i.split('.')[0],
                                      globals(), locals(), ['RFIDReader'], -1)
                devtemp = _tempmod.RFIDReader()
                if devtemp.get_present() == True:
                    device = devtemp
            except Exception, e:
                _logger.error("FIND_DEVICE: %s: %s" % (i, e))
                pass
    return device


class noKeyError(UserDict):

    __missing__ = lambda x, y: 0


class symbol:

    def __init__(self, name):
        self.name = name
        self.nargs = None
        self.fcn = None

    def __str__(self):
        return self.name

    def __repr__(self):
        return '#' + self.name


class logoerror(Exception):

    def __init__(self, value):
        self.value = value

    def __str__(self):
        return repr(self.value)

# Utility functions


def _num_type(x):
    """ Is x a number type? """
    if type(x) == int:
        return True
    if type(x) == float:
        return True
    if type(x) == ord:
        return True
    return False


def _string_to_num(x):
    """ Try to comvert a string to a number """
    xx = convert(x.replace(self.tw.decimal_point, '.'), float)
    if type(xx) is float:
        return xx
    else:
        xx, xflag = chr_to_ord(x)
        if xflag:
            return xx
        else:
            raise logoerror("#syntaxerror")


def _and(x, y):
    """ Logical and """
    return x & y


def _or(x, y):
    """ Logical or """
    return x | y


def _careful_divide(x, y):
    """ Raise error on divide by zero """
    try:
        return x / y
    except ZeroDivisionError:
        raise logoerror("#zerodivide")
    except TypeError:
        try:
            return _string_to_num(x) / _string_to_num(y)
        except ZeroDivisionError:
            raise logoerror("#zerodivide")
        except ValueError:
            raise logoerror("#syntaxerror")
        except TypeError:
            raise logoerror("#notanumber")


def _equal(x, y):
    """ Numeric and logical equal """
    try:
        return float(x) == float(y)
    except TypeError:
        typex, typey = False, False
        if strtype(x):
            typex = True
        if strtype(y):
            typey = True
        if typex and typey:
            return x == y
        try:
            return _string_to_num(x) == _string_to_num(y)
        except ValueError:
            raise logoerror("#syntaxerror")


def _less(x, y):
    """ Compare numbers and strings """
    try:
        return float(x) < float(y)
    except ValueError:
        typex, typey = False, False
        if strtype(x):
            typex = True
        if strtype(y):
            typey = True
        if typex and typey:
            return x < y
        try:
            return _string_to_num(x) < _string_to_num(y)
        except TypeError:
            raise logoerror("#notanumber")


def _more(x, y):
    """ Compare numbers and strings """
    return _less(y, x)


def _plus(x, y):
    """ Add numbers, concat strings """
    if _num_type(x) and _num_type(y):
        return(x + y)
    else:
        if _num_type(x):
            xx = str(round_int(x))
        else:
            xx = str(x)
        if _num_type(y):
            yy = str(round_int(y))
        else:
            yy = str(y)
        return(xx + yy)


def _minus(x, y):
    """ Numerical subtraction """
    if _num_type(x) and _num_type(y):
        return(x - y)
    try:
        return _string_to_num(x) - _string_to_num(y)
    except TypeError:
        raise logoerror("#notanumber")


def _product(x, y):
    """ Numerical multiplication """
    if _num_type(x) and _num_type(y):
        return(x * y)
    try:
        return _string_to_num(x) * _string_to_num(y)
    except TypeError:
        raise logoerror("#notanumber")


def _mod(x, y):
    """ Numerical mod """
    if _num_type(x) and _num_type(y):
        return(x % y)
    try:
        return _string_to_num(x) % _string_to_num(y)
    except TypeError:
        raise logoerror("#notanumber")
    except ValueError:
        raise logoerror("#syntaxerror")


def _sqrt(x):
    """ Square root """
    if _num_type(x):
        if x < 0:
            raise logoerror("#negroot")
        return sqrt(x)
    try:
        return sqrt(_string_to_num(x))
    except ValueError:
        raise logoerror("#negroot")
    except TypeError:
        raise logoerror("#notanumber")


def _random(x, y):
    """ Random integer """
    if _num_type(x) and _num_type(y):
        return(int(round(uniform(x, y), 0)))
    xx, xflag = chr_to_ord(x)
    yy, yflag = chr_to_ord(y)
    if xflag and yflag:
        return chr(int(round(uniform(xx, yy), 0)))
    if not xflag:
        xx = _string_to_num(x)
    if not yflag:
        yy = _string_to_num(y)
    try:
        return(int(round(uniform(xx, yy), 0)))
    except TypeError:
        raise logoerror("#notanumber")


def _identity(x):
    """ Identity function """
    return(x)


def _avg(array, abs_value=False):
    """ Calc. the average value of an array """
    if len(array) == 0:
        return 0
    array_sum = 0
    if abs_value:
        for a in array:
            array_sum += abs(a)
    else:
        for a in array:
            array_sum += a
    return float(array_sum) / len(array)


def _just_stop():
    """ yield False to stop stack """
    yield False


def _millisecond():
    """ Current time in milliseconds """
    return time() * 1000


class LogoCode:
    """ A class for parsing Logo code """

    def __init__(self, tw):

        self.tw = tw
        self.oblist = {}

        DEFPRIM = {
        '(': [1, lambda self, x: self._prim_opar(x)],
        'and': [2, lambda self, x, y: _and(x, y)],
        'arc': [2, lambda self, x, y: self._prim_arc(self.tw.canvas.arc, x,
                                                     y)],
        'audio': [1, lambda self, x: self._play_sound(x)],
        'back': [1, lambda self, x: self._prim_move(self.tw.canvas.forward,
                                                    -x)],
        'black': [0, lambda self: BLACK],
        'blue': [0, lambda self: CONSTANTS['blue']],
        'bpos': [0, lambda self: CONSTANTS['bottompos']],
        'boty': [0, lambda self: CONSTANTS['bottomy']],
        'box1': [0, lambda self: self.boxes['box1']],
        'box': [1, lambda self, x: self._box(x)],
        'box2': [0, lambda self: self.boxes['box2']],
        'bullet': [1, self._prim_bullet, True],
        'bulletlist': [1, self._prim_list, True],
        'cartesian': [0, lambda self: self.tw.set_cartesian(True)],
        'clean': [0, lambda self: self.prim_clear()],
        'clearheap': [0, lambda self: self._empty_heap()],
        'color': [0, lambda self: self.tw.canvas.color],
        'gray': [0, lambda self: self.tw.canvas.gray],
        'comment': [1, lambda self, x: self._prim_print(x, True)],
        'container': [1, lambda self, x: x],
        'cyan': [0, lambda self: CONSTANTS['cyan']],
        'define': [2, self._prim_define],
        'division': [2, lambda self, x, y: _careful_divide(x, y)],
        'equal?': [2, lambda self, x, y: _equal(x, y)],
        'fillscreen': [2, lambda self, x, y: self.tw.canvas.fillscreen(x, y)],
        'forever': [1, self._prim_forever, True],
        'forward': [1, lambda self, x: self._prim_move(self.tw.canvas.forward,
                                                      x)],
        'fullscreen': [0, lambda self: self.tw.set_fullscreen()],
        'greater?': [2, lambda self, x, y: _more(x, y)],
        'green': [0, lambda self: CONSTANTS['green']],
        'heading': [0, lambda self: self.tw.canvas.heading],
        'hideblocks': [0, lambda self: self.tw.hideblocks()],
        'hres': [0, lambda self: CONSTANTS['width']],
        'id': [1, lambda self, x: _identity(x)],
        'if': [2, self._prim_if, True],
        'ifelse': [3, self._prim_ifelse, True],
        'insertimage': [1, lambda self, x: self._insert_image(False,
                                                              filepath=x)],
        'kbinput': [0, lambda self: self._prim_kbinput()],
        'keyboard': [0, lambda self: self.keyboard],
        'left': [1, lambda self, x: self._prim_right(-x)],
        'leftx': [0, lambda self: CONSTANTS['leftx']],
        'lpos': [0, lambda self: CONSTANTS['leftpos']],
        'less?': [2, lambda self, x, y: _less(x, y)],
        'luminance': [0, lambda self: self._read_camera(True)],
        'mediawait': [0, self._media_wait, True],
        'minus': [2, lambda self, x, y: _minus(x, y)],
        'mod': [2, lambda self, x, y: _mod(x, y)],
        'myfunction': [2, lambda self, f, x: self._myfunction(f, [x])],
        'myfunction2': [3, lambda self, f, x, y: self._myfunction(f, [x, y])],
        'myfunction3': [4, lambda self, f, x, y, z: self._myfunction(
                    f, [x, y, z])],
        'nop': [0, lambda self: None],
        'nop1': [0, lambda self: None],
        'nop2': [0, lambda self: None],
        'nop3': [1, lambda self, x: None],
        'not': [1, lambda self, x: not x],
        'orange': [0, lambda self: CONSTANTS['orange']],
        'or': [2, lambda self, x, y: _or(x, y)],
        'pendown': [0, lambda self: self.tw.canvas.setpen(True)],
        'pensize': [0, lambda self: self.tw.canvas.pensize],
        'penup': [0, lambda self: self.tw.canvas.setpen(False)],
        'pitch': [0, lambda self: self._get_pitch()],
        'plus': [2, lambda self, x, y: _plus(x, y)],
        'polar': [0, lambda self: self.tw.set_polar(True)],
        'pop': [0, lambda self: self._prim_pop()],
        'print': [1, lambda self, x: self._prim_print(x, False)],
        'printheap': [0, lambda self: self._prim_print_heap()],
        'product': [2, lambda self, x, y: _product(x, y)],
        'purple': [0, lambda self: CONSTANTS['purple']],
        'push': [1, lambda self, x: self._prim_push(x)],
        'random': [2, lambda self, x, y: _random(x, y)],
        'readcamera': [0, lambda self: self._read_camera()],
        'readpixel': [0, lambda self: self._read_pixel()],
        'red': [0, lambda self: CONSTANTS['red']],
        'repeat': [2, self._prim_repeat, True],
        'resistance': [0, lambda self: self._get_resistance()],
        'rfid': [0, lambda self: self.tw.rfid_idn],
        'right': [1, lambda self, x: self._prim_right(x)],
        'rightx': [0, lambda self: CONSTANTS['rightx']],
        'rpos': [0, lambda self: CONSTANTS['rightpos']],
        'savepix': [1, lambda self, x: self._save_picture(x)],
        'savesvg': [1, lambda self, x: self._save_svg(x)],
        'scale': [0, lambda self: self.scale],
        'see': [0, lambda self: self.see()],
        'setcolor': [1, lambda self, x: self._prim_set('color',
            self.tw.canvas.setcolor, x)],
        'setgray': [1, lambda self, x: self._prim_set('gray',
            self.tw.canvas.setgray, x)],
        'seth': [1, lambda self, x: self._prim_set('heading',
            self.tw.canvas.seth, x)],
        'setpensize': [1, lambda self, x: self._prim_set('pensize',
            self.tw.canvas.setpensize, x)],
        'setscale': [1, lambda self, x: self._prim_set('scale',
            self._set_scale, x)],
        'setshade': [1, lambda self, x: self._prim_set('shade',
            self.tw.canvas.setshade, x)],
        'settextcolor': [1, lambda self, x: self.tw.canvas.settextcolor(x)],
        'settextsize': [1, lambda self, x: self.tw.canvas.settextsize(x)],
        'setxy2': [2, lambda self, x, y: self._prim_move(self.tw.canvas.setxy,
                                                        x, y)],
        'setxy': [2, lambda self, x, y: self._prim_move(self.tw.canvas.setxy,
                                                        x, y, pendown=False)],
        'shade': [0, lambda self: self.tw.canvas.shade],
        'show': [1, lambda self, x: self._show(x, True)],
        'showaligned': [1, lambda self, x: self._show(x, False)],
        'showblocks': [0, lambda self: self.tw.showblocks()],
        'skin': [1, lambda self, x: self._reskin(x)],
        'sound': [0, lambda self: self._get_sound()],
        'sqrt': [1, lambda self, x: _sqrt(x)],
        'stack1': [0, self._prim_stack1, True],
        'stack': [1, self._prim_stack, True],
        'stack2': [0, self._prim_stack2, True],
        'start': [0, lambda self: self._prim_start()],
        'startfill': [0, lambda self: self.tw.canvas.start_fill()],
        'stopfill': [0, lambda self: self.tw.canvas.stop_fill()],
        'stopstack': [0, lambda self: self._prim_stopstack()],
        'storeinbox1': [1, lambda self, x: self._prim_setbox('box1', None, x)],
        'storeinbox2': [1, lambda self, x: self._prim_setbox('box2', None, x)],
        'storeinbox': [2, lambda self, x, y: self._prim_setbox('box3', x, y)],
        't1x1': [2, lambda self, x, y: self._show_template1x1(x, y)],
        't1x1a': [2, lambda self, x, y: self._show_template1x1a(x, y)],
        't1x2': [3, lambda self, x, y, z: self._show_template1x2(x, y, z)],
        't2x1': [3, lambda self, x, y, z: self._show_template2x1(x, y, z)],
        't2x2': [5, lambda self, x, y, z, a, b: self._show_template2x2(
                    x, y, z, a, b)],
        'textcolor': [0, lambda self: self.tw.canvas.textcolor],
        'textsize': [0, lambda self: self.tw.textsize],
        'time': [0, lambda self: self._elapsed_time()],
        'titlex': [0, lambda self: CONSTANTS['titlex']],
        'titley': [0, lambda self: CONSTANTS['titley']],
        'topy': [0, lambda self: CONSTANTS['topy']],
        'tpos': [0, lambda self: CONSTANTS['toppos']],
        'turtle': [1, lambda self, x: self.tw.canvas.set_turtle(x)],
        'userdefined': [1, lambda self, x: self._prim_myblock([x])],
        'userdefined2': [2, lambda self, x, y: self._prim_myblock([x, y])],
        'userdefined3': [3, lambda self, x, y,
                         z: self._prim_myblock([x, y, z])],
        'video': [1, lambda self, x: self._play_video(x)],
        'voltage': [0, lambda self: self._get_voltage()],
        'volume': [0, lambda self: self._get_volume()],
        'vres': [0, lambda self: CONSTANTS['height']],
        'wait': [1, self._prim_wait, True],
        'white': [0, lambda self: WHITE],
        'write': [2, lambda self, x, y: self._write(self, x, y)],
        'xcor': [0, lambda self: self.tw.canvas.xcor / self.tw.coord_scale],
        'ycor': [0, lambda self: self.tw.canvas.ycor / self.tw.coord_scale],
        'yellow': [0, lambda self: CONSTANTS['yellow']]}

        for p in iter(DEFPRIM):
            if len(DEFPRIM[p]) == 2:
                self._def_prim(p, DEFPRIM[p][0], DEFPRIM[p][1])
            else:
                self._def_prim(p, DEFPRIM[p][0], DEFPRIM[p][1], DEFPRIM[p][2])

        self.symtype = type(self._intern('print'))
        self.listtype = type([])
        self.symnothing = self._intern('%nothing%')
        self.symopar = self._intern('(')
        self.iline = None
        self.cfun = None
        self.arglist = None
        self.ufun = None
        self.procstop = False
        self.running = False
        self.istack = []
        self.stacks = {}
        self.boxes = {'box1': 0, 'box2': 0}
        self.heap = []
        self.iresults = None
        self.step = None
        self.bindex = None

        self.hidden_turtle = None

        self.keyboard = 0
        self.trace = 0
        self.update_values = False
        self.gplay = None
        self.ag = None
        self.filepath = None
        self.dsobject = None
        self._start_time = None

        # Scale factors for depreciated portfolio blocks
        self.title_height = int((self.tw.canvas.height / 20) * self.tw.scale)
        self.body_height = int((self.tw.canvas.height / 40) * self.tw.scale)
        self.bullet_height = int((self.tw.canvas.height / 30) * self.tw.scale)

        self.scale = DEFAULT_SCALE

        self.max_samples = 1500
        self.input_step = 1

        self.ringbuffer = RingBuffer1d(self.max_samples, dtype='int16')
        if self.tw.hw == XO1:
            self.voltage_gain = 0.00002225
            self.voltage_bias = 1.140
        elif self.tw.hw == XO15:
            self.voltage_gain = -0.0001471
            self.voltage_bias = 1.695

        if self.tw.camera_available:
            if self.tw.running_sugar:
                self.imagepath = get_path(self.tw.activity,
                                          'data/turtlepic.png')
            else:
                self.imagepath = '/tmp/turtlepic.png'
            from tacamera import Camera
            self.camera = Camera(self.imagepath)

    def stop_logo(self):
        """ Stop logo is called from the Stop button on the toolbar """
        self.tw.step_time = 0
        self.step = _just_stop()
        if self.tw.gst_available:
            from tagplay import stop_media
            stop_media(self)
            if self.tw.camera_available:
                self.camera.stop_camera_input()
            self.tw.active_turtle.show()

    def _def_prim(self, name, args, fcn, rprim=False):
        """ Define the primitives associated with the blocks """
        sym = self._intern(name)
        sym.nargs, sym.fcn = args, fcn
        sym.rprim = rprim

    def _intern(self, string):
        """ Add any new objects to the symbol list. """
        if string in self.oblist:
            return self.oblist[string]
        sym = symbol(string)
        self.oblist[string] = sym
        return sym

    def run_blocks(self, blk, blocks, run_flag):
        """ Given a block to run... """
        for k in self.stacks.keys():
            self.stacks[k] = None
        self.stacks['stack1'] = None
        self.stacks['stack2'] = None
        self.tw.saving_svg = False

        self.find_value_blocks()
        self._update_audio_mode()
        if self.trace > 0:
            self.update_values = True
        else:
            self.update_values = False

        for b in blocks:
            b.unhighlight()
            if b.name == 'hat1':
                code = self._blocks_to_code(b)
                self.stacks['stack1'] = self._readline(code)
            if b.name == 'hat2':
                code = self._blocks_to_code(b)
                self.stacks['stack2'] = self._readline(code)
            if b.name == 'hat':
                if b.connections is not None and len(b.connections) > 1 and \
                   b.connections[1] is not None:
                    code = self._blocks_to_code(b)
                    x = b.connections[1].values[0]
                    if type(convert(x, float, False)) == float:
                        if int(float(x)) == x:
                            x = int(x)
                    self.stacks['stack3' + str(x)] = self._readline(code)

        code = self._blocks_to_code(blk)
        if run_flag:
            _logger.debug("running code: %s" % (code))
            self._start_time = time()
            self._setup_cmd(code)
            if not self.tw.hide:
                self.tw.display_coordinates()
        else:
            return code

    def _blocks_to_code(self, blk):
        """ Convert a stack of blocks to pseudocode. """
        if blk is None:
            return ['%nothing%', '%nothing%']
        code = []
        dock = blk.docks[0]
        if len(dock) > 4:  # There could be a '(', ')', '[' or ']'.
            code.append(dock[4])
        if blk.name == 'savesvg':
            self.tw.saving_svg = True
        if blk.primitive is not None:  # make a tuple (prim, blk)
            code.append((blk.primitive, self.tw.block_list.list.index(blk)))
        elif len(blk.values) > 0:  # Extract the value from content blocks.
            if blk.name == 'number':
                try:
                    code.append(float(blk.values[0]))
                except ValueError:
                    code.append(float(ord(blk.values[0][0])))
            elif blk.name == 'string' or blk.name == 'title':
                if type(blk.values[0]) == float or type(blk.values[0]) == int:
                    if int(blk.values[0]) == blk.values[0]:
                        blk.values[0] = int(blk.values[0])
                    code.append('#s' + str(blk.values[0]))
                else:
                    code.append('#s' + blk.values[0])
            elif blk.name == 'journal':
                if blk.values[0] is not None:
                    code.append('#smedia_' + str(blk.values[0]))
                else:
                    code.append('#smedia_None')
            elif blk.name == 'description':
                if blk.values[0] is not None:
                    code.append('#sdescr_' + str(blk.values[0]))
                else:
                    code.append('#sdescr_None')
            elif blk.name == 'audio':
                if blk.values[0] is not None:
                    code.append('#saudio_' + str(blk.values[0]))
                else:
                    code.append('#saudio_None')
            elif blk.name == 'video':
                if blk.values[0] is not None:
                    code.append('#svideo_' + str(blk.values[0]))
                else:
                    code.append('#svideo_None')
            elif blk.name == 'camera':
                    code.append('#smedia_CAMERA')
            else:
                return ['%nothing%']
        else:
            return ['%nothing%']
        if blk.connections is not None and len(blk.connections) > 0:
            for i in range(1, len(blk.connections)):
                b = blk.connections[i]
                dock = blk.docks[i]
                if len(dock) > 4:  # There could be a '(', ')', '[' or ']'.
                    for c in dock[4]:
                        code.append(c)
                if b is not None:
                    code.extend(self._blocks_to_code(b))
                elif blk.docks[i][0] not in ['flow', 'unavailable']:
                    code.append('%nothing%')
        return code

    def _setup_cmd(self, string):
        """ Execute the psuedocode. """
        self.hidden_turtle = self.tw.active_turtle
        self.hidden_turtle.hide()  # Hide the turtle while we are running.
        self.procstop = False
        blklist = self._readline(string)
        self.step = self._start_eval(blklist)

    def _readline(self, line):
        """
        Convert the pseudocode into a list of commands.
        The block associated with the command is stored as the second element
        in a tuple, e.g., (#forward, 16)
        """
        res = []
        while line:
            token = line.pop(0)
            bindex = None
            if type(token) == tuple:
                (token, bindex) = token
            if isNumberType(token):
                res.append(token)
            elif token.isdigit():
                res.append(float(token))
            elif token[0] == '-' and token[1:].isdigit():
                res.append(-float(token[1:]))
            elif token[0] == '"':
                res.append(token[1:])
            elif token[0:2] == "#s":
                res.append(token[2:])
            elif token == '[':
                res.append(self._readline(line))
            elif token == ']':
                return res
            elif bindex is None or type(bindex) is not int:
                res.append(self._intern(token))
            else:
                res.append((self._intern(token), bindex))
        return res

    def _start_eval(self, blklist):
        """ Step through the list. """
        if self.tw.running_sugar:
            self.tw.activity.stop_turtle_button.set_icon("stopiton")
        elif self.tw.interactive_mode:
            self.tw.toolbar_shapes['stopiton'].set_layer(TAB_LAYER)
        self.running = True
        self._icall(self._evline, blklist)
        yield True
        if self.tw.running_sugar:
            self.tw.activity.stop_turtle_button.set_icon("stopitoff")
        elif self.tw.interactive_mode:
            self.tw.toolbar_shapes['stopiton'].hide()
        yield False
        self.running = False

    def _icall(self, fcn, *args):
        """ Add a function and its arguments to the program stack. """
        self.istack.append(self.step)
        self.step = fcn(*(args))

    def _evline(self, blklist):
        """ Evaluate a line of code from the list. """
        oldiline = self.iline
        self.iline = blklist[:]
        self.arglist = None
        while self.iline:
            token = self.iline[0]
            self.bindex = None
            if type(token) == tuple:
                (token, self.bindex) = self.iline[0]

            # If the blocks are visible, highlight the current block.
            if not self.tw.hide and self.bindex is not None:
                self.tw.block_list.list[self.bindex].highlight()

            # In debugging modes, we pause between steps and show the turtle.
            if self.tw.step_time > 0:
                self.tw.active_turtle.show()
                endtime = _millisecond() + self.tw.step_time * 100.
                while _millisecond() < endtime:
                    yield True
                self.tw.active_turtle.hide()

            # 'Stand-alone' booleans are handled here.
            if token == self.symopar:
                token = self.iline[1]
                if type(token) == tuple:
                    (token, self.bindex) = self.iline[1]

            # Process the token and any arguments.
            self._icall(self._eval)
            yield True

            # Time to unhighlight the current block.
            if not self.tw.hide and self.bindex is not None:
                self.tw.block_list.list[self.bindex].unhighlight()

            if self.procstop:
                break
            if self.iresult == None:
                continue

            if self.bindex is not None:
                self.tw.block_list.list[self.bindex].highlight()
            raise logoerror(str(self.iresult))
        self.iline = oldiline
        self._ireturn()
        if not self.tw.hide and self.tw.step_time > 0:
            self.tw.display_coordinates()
        yield True

    def _eval(self):
        """ Evaluate the next token on the line of code we are processing. """
        token = self.iline.pop(0)
        bindex = None
        if type(token) == tuple:
            (token, bindex) = token

        # Either we are processing a symbol or a value.
        if type(token) == self.symtype:
            # We highlight blocks here in case an error occurs...
            if not self.tw.hide and bindex is not None:
                self.tw.block_list.list[bindex].highlight()
            self._icall(self._evalsym, token)
            yield True
            # and unhighlight if everything was OK.
            if not self.tw.hide and bindex is not None:
                self.tw.block_list.list[bindex].unhighlight()
            res = self.iresult
        else:
            res = token

        self._ireturn(res)
        yield True

    def _evalsym(self, token):
        """ Process primitive associated with symbol token """
        self._undefined_check(token)
        oldcfun, oldarglist = self.cfun, self.arglist
        self.cfun, self.arglist = token, []

        if token.nargs == None:
            raise logoerror("#noinput")
        for i in range(token.nargs):
            self._no_args_check()
            self._icall(self._eval)
            yield True
            self.arglist.append(self.iresult)
        if self.cfun.rprim:
            if type(self.cfun.fcn) == self.listtype:
                _logger.debug("evalsym rprim list: %s" % (str(token)))
                self._icall(self._ufuncall, self.cfun.fcn)
                yield True
            else:
                # print "evalsym rprim: ", token
                self._icall(self.cfun.fcn, *self.arglist)
                yield True
            result = None
        else:
            # print "evalsym: ", token
            result = self.cfun.fcn(self, *self.arglist)
        self.cfun, self.arglist = oldcfun, oldarglist
        if self.arglist is not None and result == None:
            raise logoerror("%s %s %s" % \
                (oldcfun.name, _("did not output to"), self.cfun.name))
        self._ireturn(result)
        yield True

    def _ufuncall(self, body):
        """ ufuncall """
        self._ijmp(self._evline, body)
        yield True

    def doevalstep(self):
        """ evaluate one step """
        starttime = _millisecond()
        try:
            while (_millisecond() - starttime) < 120:
                try:
                    if self.step is not None:
                        self.step.next()
                    else:
                        return False
                except StopIteration:
                    # self.tw.turtles.show_all()
                    if self.hidden_turtle is not None:
                        self.hidden_turtle.show()
                        self.hidden_turtle = None
                    else:
                        self.tw.active_turtle.show()
                    return False
        except logoerror, e:
            self.tw.showlabel('syntaxerror', str(e)[1:-1])
            self.tw.turtles.show_all()
            return False
        return True

    def _ireturn(self, res=None):
        """ return value """
        self.step = self.istack.pop()
        self.iresult = res

    def _ijmp(self, fcn, *args):
        """ ijmp """
        self.step = fcn(*(args))

    def _undefined_check(self, token):
        """ Make sure token has a definition """
        if token.fcn is not None:
            return False
        if token.name == '%nothing%':
            errormsg = ''
        else:
            errormsg = "%s %s" % (_("I don't know how to"), _(token.name))
        raise logoerror(errormsg)

    def _no_args_check(self):
        """ Missing argument ? """
        if self.iline and self.iline[0] is not self.symnothing:
            return
        raise logoerror("#noinput")

    #
    # Primitives
    #

    def prim_clear(self):
        """ Clear screen """
        if self.tw.gst_available:
            from tagplay import stop_media
            stop_media(self)
        self.tw.canvas.clearscreen()
        self.scale = DEFAULT_SCALE
        # Note: users find this "feature" confusing
        # self.tw.set_polar(False)
        # self.tw.set_cartesian(False)
        self.hidden_turtle = None
        self._start_time = time()
        for name in VALUE_BLOCKS:
            self.update_label_value(name)

    def _prim_start(self):
        """ Start block: recenter """
        if self.tw.running_sugar:
            self.tw.activity.recenter()

    def _prim_wait(self, time):
        """ Show the turtle while we wait """
        self.tw.active_turtle.show()
        endtime = _millisecond() + time * 1000.
        while _millisecond() < endtime:
            yield True
        self.tw.active_turtle.hide()
        self._ireturn()
        yield True

    def _prim_repeat(self, num, blklist):
        """ Repeat list num times. """
        num = self._int(num)
        for i in range(num):
            self._icall(self._evline, blklist[:])
            yield True
            if self.procstop:
                break
        self._ireturn()
        yield True

    def _prim_bullet(self, blklist):
        """ Depreciated bullet-list block style """
        self._show_bullets(blklist)
        self._ireturn()
        yield True

    def _prim_list(self, blklist):
        """ Expandable list block """
        self._show_list(blklist)
        self._ireturn()
        yield True

    def _myfunction(self, f, x):
        """ Programmable block """
        try:
            y = myfunc(f, x)
            if str(y) == 'nan':
                _logger.debug("python function returned nan")
                self.stop_logo()
                raise logoerror("#notanumber")
            else:
                return y
        except ZeroDivisionError:
            self.stop_logo()
            raise logoerror("#zerodivide")
        except ValueError, e:
            self.stop_logo()
            raise logoerror('#' + str(e))
        except SyntaxError, e:
            self.stop_logo()
            raise logoerror('#' + str(e))
        except NameError, e:
            self.stop_logo()
            raise logoerror('#' + str(e))
        except OverflowError:
            self.stop_logo()
            raise logoerror("#overflowerror")
        except TypeError:
            self.stop_logo()
            raise logoerror("#notanumber")

    def _prim_forever(self, blklist):
        """ Do list forever """
        while True:
            self._icall(self._evline, blklist[:])
            yield True
            if self.procstop:
                break
        self._ireturn()
        yield True

    '''
    def _prim_while(self, list1, list2):
        list = [self._intern('if')]
        for i in list1:
            list.append(i)
        list.append(list2)
        while self._icall(self._evline, list[:]):
            yield True
        self._ireturn()
        yield True
    '''

    def _prim_if(self, boolean, blklist):
        """ If bool, do list """
        if boolean:
            self._icall(self._evline, blklist[:])
            yield True
        self._ireturn()
        yield True

    def _prim_ifelse(self, boolean, list1, list2):
        """ If bool, do list1, else do list2 """
        if boolean:
            self._ijmp(self._evline, list1[:])
            yield True
        else:
            self._ijmp(self._evline, list2[:])
            yield True

    def _prim_opar(self, val):
        self.iline.pop(0)
        return val

    def _prim_define(self, name, body):
        """ Define a primitive """
        if type(name) is not self.symtype:
            name = self._intern(name)
        name.nargs, name.fcn = 0, body
        name.rprim = True

    def _prim_stack(self, x):
        """ Process a named stack """
        if type(convert(x, float, False)) == float:
            if int(float(x)) == x:
                x = int(x)
        if 'stack3' + str(x) not in self.stacks or\
           self.stacks['stack3' + str(x)] is None:
            raise logoerror("#nostack")
        self._icall(self._evline, self.stacks['stack3' + str(x)][:])
        yield True
        self.procstop = False
        self._ireturn()
        yield True

    def _prim_stack1(self):
        """ Process Stack 1 """
        if self.stacks['stack1'] is None:
            raise logoerror("#nostack")
        self._icall(self._evline, self.stacks['stack1'][:])
        yield True
        self.procstop = False
        self._ireturn()
        yield True

    def _prim_stack2(self):
        """ Process Stack 2 """
        if self.stacks['stack2'] is None:
            raise logoerror("#nostack")
        self._icall(self._evline, self.stacks['stack2'][:])
        yield True
        self.procstop = False
        self._ireturn()
        yield True

    def _prim_stopstack(self):
        """ Stop execution of a stack """
        self.procstop = True

    def _prim_print_heap(self):
        """ Display contents of heap """
        self.tw.showlabel('status', str(self.heap) + '      ')

    def _int(self, n):
        """ Raise an error if n doesn't convert to int. """
        if type(n) == int:
            return n
        elif type(n) == float:
            return int(n)
        elif type(n) == str:
            return int(ord(n[0]))
        else:
            raise logoerror("%s %s %s %s" \
                % (self.cfun.name, _("doesn't like"), str(n), _("as input")))

    def _box(self, x):
        """ Retrieve value from named box """
        if type(convert(x, float, False)) == float:
            if int(float(x)) == x:
                x = int(x)
        try:
            return self.boxes['box3' + str(x)]
        except KeyError:
            raise logoerror("#emptybox")

    def _prim_myblock(self, x):
        """ Run Python code imported from Journal """
        if self.bindex is not None and self.bindex in self.tw.myblock:
            try:
                if len(x) == 1:
                    myfunc_import(self, self.tw.myblock[self.bindex], x[0])
                else:
                    myfunc_import(self, self.tw.myblock[self.bindex], x)
            except:
                raise logoerror("#syntaxerror")

    def _prim_print(self, n, flag):
        """ Print object n """
        if flag and (self.tw.hide or self.tw.step_time == 0):
            return
        if type(n) == str or type(n) == unicode:
            if n[0:6] == 'media_' and n[6:] != 'CAMERA':
                try:
                    if self.tw.running_sugar:
                        try:
                            dsobject = datastore.get(n[6:])
                        except:
                            _logger.debug("Couldn't open %s" % (n[6:]))
                        self.tw.showlabel('status', dsobject.metadata['title'])
                        dsobject.destroy()
                    else:
                        self.tw.showlabel('status', n[6:])
                except IOError:
                    self.tw.showlabel('status', n)
            else:
                self.tw.showlabel('status', n)
        elif type(n) == int:
            self.tw.showlabel('status', n)
        else:
            self.tw.showlabel('status',
                str(round_int(n)).replace('.', self.tw.decimal_point))

    def _prim_kbinput(self):
        """ Query keyboard """
        if len(self.tw.keypress) == 1:
            self.keyboard = ord(self.tw.keypress[0])
        else:
            try:
                self.keyboard = {'Escape': 27, 'space': 32, ' ': 32,
                                 'Return': 13, \
                                 'KP_Up': 2, 'KP_Down': 4, 'KP_Left': 1, \
                                 'KP_Right': 3}[self.tw.keypress]
            except KeyError:
                self.keyboard = 0
        self.update_label_value('keyboard', self.keyboard)
        self.tw.keypress = ''

    def find_value_blocks(self):
        """ Find any value blocks that may need label updates """
        self.value_blocks = {}
        for name in VALUE_BLOCKS:
            self.value_blocks[name] = self.tw.block_list.get_similar_blocks(
                'block', name)

    def _update_audio_mode(self):
        """ If there are sensor blocks, set the appropriate audio mode """
        if not self.tw.gst_available:
            return
        for name in ['sound', 'volume', 'pitch']:
            if len(self.value_blocks[name]) > 0:
                self.tw.audiograb.set_sensor_type()
                return
        if len(self.value_blocks['resistance']) > 0:
            self.tw.audiograb.set_sensor_type(SENSOR_DC_BIAS)
            return
        elif len(self.value_blocks['voltage']) > 0:
            self.tw.audiograb.set_sensor_type(SENSOR_DC_NO_BIAS)
            return

    def update_label_value(self, name, value=None):
        """ Update the label of value blocks to reflect current value """
        if self.tw.hide or not self.tw.interactive_mode or \
           not hasattr(self, 'value_blocks'):
            return
        if value is None:
            for block in self.value_blocks[name]:
                block.spr.set_label(BLOCK_NAMES[name][0])
                block.resize()
        elif self.update_values:
            if type(value) == float:
                valstring = str(round_int(value)).replace('.',
                    self.tw.decimal_point)
            else:
                valstring = str(value)
            for block in self.value_blocks[name]:
                block.spr.set_label(BLOCK_NAMES[name][0] + ' = ' + valstring)
                block.resize()

    def _prim_set(self, name, cmd, value=None):
        """ Set a value and update the associated value blocks """
        if value is not None:
            cmd(value)
            self.update_label_value(name, value)

    def _prim_right(self, value):
        self.tw.canvas.right(float(value))
        self.update_label_value('heading', self.tw.canvas.heading)

    def _prim_move(self, cmd, value1, value2=None, pendown=True):
        if value2 is None:
            cmd(value1)
        else:
            cmd(float(value1), float(value2), pendown=pendown)
        self.update_label_value('xcor',
                           self.tw.canvas.xcor / self.tw.coord_scale)
        self.update_label_value('ycor',
                           self.tw.canvas.ycor / self.tw.coord_scale)
        if len(self.value_blocks['see']) > 0:
            self.see()

    def _prim_arc(self, cmd, value1, value2):
        cmd(float(value1), float(value2))
        self.update_label_value('xcor',
                           self.tw.canvas.xcor / self.tw.coord_scale)
        self.update_label_value('ycor',
                           self.tw.canvas.ycor / self.tw.coord_scale)
        self.update_label_value('heading', self.tw.canvas.heading)
        if len(self.value_blocks['see']) > 0:
            self.see()

    def _prim_setbox(self, name, x, val):
        """ Define value of named box """
        if x is not None:
            if type(convert(x, float, False)) == float:
                if int(float(x)) == x:
                    x = int(x)
            self.boxes[name + str(x)] = val
            return

        self.boxes[name] = val
        self.update_label_value(name, val)

    def _prim_push(self, val):
        """ Push value onto FILO """
        self.heap.append(val)
        self.update_label_value('pop', val)

    def _prim_pop(self):
        """ Pop value off of FILO """
        if len(self.heap) == 0:
            raise logoerror("#emptyheap")
        else:
            if len(self.heap) == 1:
                self.update_label_value('pop')
            else:
                self.update_label_value('pop', self.heap[-2])
            return self.heap.pop(-1)

    def push_file_data_to_heap(self, dsobject):
        """ push contents of a data store object (assuming json encoding) """
        data = data_from_file(dsobject.file_path)
        if data is not None:
            for val in data:
                self.heap.append(val)
            self.update_label_value('pop', self.heap[-1])

    def _empty_heap(self):
        """ Empty FILO """
        self.heap = []

    def _save_picture(self, name):
        """ Save canvas to file as PNG """
        self.tw.save_as_image(name)

    def _save_svg(self, name):
        """ Save SVG to file """
        self.tw.canvas.svg_close()
        self.tw.save_as_image(name, True)

    def _show_list(self, sarray):
        """ Display list of media objects """
        x = self.tw.canvas.xcor / self.tw.coord_scale
        y = self.tw.canvas.ycor / self.tw.coord_scale
        for s in sarray:
            self.tw.canvas.setxy(x, y, pendown=False)
            self._show(s)
            y -= int(self.tw.canvas.textsize * self.tw.lead)

    def _set_scale(self, x):
        """ Set scale used by media object display """
        self.scale = x

    def _reskin(self, media):
        """ Reskin the turtle with an image from a file """
        scale = int(ICON_SIZE * float(self.scale) / DEFAULT_SCALE)
        if scale < 1:
            return
        self.filepath = None
        dsobject = None
        if os.path.exists(media[6:]):  # is it a path?
            self.filepath = media[6:]
        elif self.tw.running_sugar:  # is it a datastore object?
            try:
                dsobject = datastore.get(media[6:])
            except:
                _logger.debug("Couldn't open skin %s" % (media[6:]))
            if dsobject is not None:
                self.filepath = dsobject.file_path
        if self.filepath == None:
            self.tw.showlabel('nojournal', self.filepath)
            return
        pixbuf = None
        try:
            pixbuf = gtk.gdk.pixbuf_new_from_file_at_size(self.filepath, scale,
                                                          scale)
        except:
            self.tw.showlabel('nojournal', self.filepath)
            _logger.debug("Couldn't open skin %s" % (self.filepath))
        if pixbuf is not None:
            self.tw.active_turtle.set_shapes([pixbuf])
            pen_state = self.tw.active_turtle.get_pen_state()
            if pen_state:
                self.tw.canvas.setpen(False)
            self.tw.canvas.forward(0)
            if pen_state:
                self.tw.canvas.setpen(True)

    def _x(self):
        """ Convert screen coordinates to turtle coordinates """
        return int(self.tw.canvas.width / 2) + int(self.tw.canvas.xcor)

    def _y(self):
        """ Convert screen coordinates to turtle coordinates """
        return int(self.tw.canvas.height / 2) - int(self.tw.canvas.ycor)

    def _w(self):
        """ Convert screen coordinates to turtle coordinates """
        return int((self.tw.canvas.width * self.scale) / 100.)

    def _h(self):
        """ Convert screen coordinates to turtle coordinates """
        return int((self.tw.canvas.height * self.scale) / 100.)

    def _show(self, string, center=False):
        """ Show is the general-purpose media-rendering block. """
        if type(string) == str or type(string) == unicode:
            if string in  ['media_', 'descr_', 'audio_', 'video_',
                           'media_None', 'descr_None', 'audio_None',
                           'video_None']:
                pass
            elif string[0:6] in ['media_', 'descr_', 'audio_', 'video_']:
                self.filepath = None
                self.dsobject = None
                if string[6:] == 'CAMERA':
                    if self.tw.camera_available:
                        self.camera.save_camera_input_to_file()
                        self.camera.stop_camera_input()
                        self.filepath = self.imagepath
                elif os.path.exists(string[6:]):  # is it a path?
                    self.filepath = string[6:]
                elif self.tw.running_sugar:  # is it a datastore object?
                    try:
                        self.dsobject = datastore.get(string[6:])
                    except:
                        _logger.debug("Couldn't find dsobject %s" % (
                                string[6:]))
                    if self.dsobject is not None:
                        self.filepath = self.dsobject.file_path
                if self.filepath == None:
                    if self.dsobject is not None:
                        self.tw.showlabel('nojournal',
                                          self.dsobject.metadata['title'])
                    else:
                        self.tw.showlabel('nojournal', string[6:])
                    _logger.debug("Couldn't open %s" % (string[6:]))
                elif string[0:6] == 'media_':
                    self._insert_image(center)
                elif string[0:6] == 'descr_':
                    mimetype = None
                    if self.dsobject is not None and \
                       'mime_type' in self.dsobject.metadata:
                        mimetype = self.dsobject.metadata['mime_type']
                    description = None
                    if self.dsobject is not None and \
                       'description' in self.dsobject.metadata:
                        description = self.dsobject.metadata['description']
                    self._insert_desc(mimetype, description)
                elif string[0:6] == 'audio_':
                    self._play_sound()
                elif string[0:6] == 'video_':
                    self._play_video()
                if self.dsobject is not None:
                    self.dsobject.destroy()
            else:  # assume it is text to display
                x = self._x()
                y = self._y()
                if center:
                    y -= self.tw.canvas.textsize
                self.tw.canvas.draw_text(string, x, y,
                                         int(self.tw.canvas.textsize * \
                                             self.scale / 100.),
                                         self.tw.canvas.width - x)
        elif type(string) == float or type(string) == int:
            string = round_int(string)
            x = self._x()
            y = self._y()
            if center:
                y -= self.tw.canvas.textsize
            self.tw.canvas.draw_text(string, x, y,
                                     int(self.tw.canvas.textsize * \
                                         self.scale / 100.),
                                     self.tw.canvas.width - x)

    def _insert_image(self, center=False, filepath=None):
        """ Image only (at current x, y) """
        if filepath is not None:
            self.filepath = filepath
        pixbuf = None
        w = self._w()
        h = self._h()
        if w < 1 or h < 1:
            return
        if self.filepath is not None and self.filepath != '':
            try:
                pixbuf = gtk.gdk.pixbuf_new_from_file_at_size(self.filepath,
                                                              w, h)
            except:
                self.tw.showlabel('nojournal', self.filepath)
                _logger.debug("Couldn't open filepath %s" % (self.filepath))
        elif self.dsobject is not None:
            try:
                pixbuf = get_pixbuf_from_journal(self.dsobject, w, h)
            except:
                self.tw.showlabel('nojournal', self.dsobject)
                _logger.debug("Couldn't open dsobject %s" % (self.dsobject))
        if pixbuf is not None:
            if center:
                self.tw.canvas.draw_pixbuf(pixbuf, 0, 0,
                                           self._x() - int(w / 2),
                                           self._y() - int(h / 2), w, h,
                                           self.filepath)
            else:
                self.tw.canvas.draw_pixbuf(pixbuf, 0, 0, self._x(), self._y(),
                                           w, h, self.filepath)

    def _insert_desc(self, mimetype=None, description=None):
        """ Description text only (at current x, y) """
        w = self._w()
        if w < 1:
            return
        text = None
        if text_media_type(self.filepath):
            if mimetype == 'application/rtf' or \
               self.filepath.endswith(('rtf')):
                text_only = RtfTextOnly()
                for line in open(self.filepath, 'r'):
                    text_only.feed(line)
                    text = text_only.output
            else:
                try:
                    f = open(self.filepath, 'r')
                    text = f.read()
                    f.close()
                except IOError:
                    self.tw.showlabel('nojournal', self.filepath)
                    _logger.debug("Couldn't open %s" % (self.filepath))
        else:
            if description is not None:
                text = str(description)
            else:
                text = self.filepath
        if text is not None:
            self.tw.canvas.draw_text(text, self._x(), self._y(),
                                     self.body_height, w)

    def _media_wait(self):
        """ Wait for media to stop playing """
        if self.tw.gst_available:
            from tagplay import media_playing
            while(media_playing(self)):
                yield True
        self._ireturn()
        yield True

    def _play_sound(self):
        """ Sound file from Journal """
        if self.tw.gst_available:
            from tagplay import play_audio_from_file
            play_audio_from_file(self, self.filepath)

    def _play_video(self):
        """ Movie file from Journal """
        w = self._w()
        h = self._h()
        if w < 1 or h < 1:
            return
        if self.tw.gst_available:
            from tagplay import play_movie_from_file
            play_movie_from_file(self, self.filepath, self._x(), self._y(),
                                 self._w(), self._h())

    def _elapsed_time(self):
        """ Number of seconds since program execution has started or
        clean (prim_clear) block encountered """
        elapsed_time = int(time() - self._start_time)
        self.update_label_value('time', elapsed_time)
        return elapsed_time

    def see(self):
        """ Read r, g, b from the canvas and return a corresponding palette
        color """
        r, g, b, a = self.tw.canvas.get_pixel()
        color_index = self.tw.canvas.get_color_index(r, g, b)
        self.update_label_value('see', color_index)
        return color_index

    def _read_pixel(self):
        """ Read r, g, b, a from the canvas and push b, g, r to the stack """
        r, g, b, a = self.tw.canvas.get_pixel()
        self.heap.append(b)
        self.heap.append(g)
        self.heap.append(r)

    def _read_camera(self, luminance_only=False):
        """ Read average pixel from camera and push b, g, r to the stack """
        pixbuf = None
        array = None
        w = self._w()
        h = self._h()
        if w > 0 and h > 0 and self.tw.camera_available:
            try:
                self._video_capture_device = open('/dev/video0', 'rw')
            except:
                self._video_capture_device = None
                _logger.debug('video capture device not available')

            if self._video_capture_device is not None:
                self._ag_control = v4l2.v4l2_control(v4l2.V4L2_CID_AUTOGAIN)
                try:
                    ioctl(self._video_capture_device, v4l2.VIDIOC_G_CTRL,
                          self._ag_control)
                    self._ag_control.value = 0  # disable AUTOGAIN
                    ioctl(self._video_capture_device, v4l2.VIDIOC_S_CTRL,
                          self._ag_control)
                except:
                    _logger.debug('AUTOGAIN control not available')

            if self._video_capture_device is not None:
                self._video_capture_device.close()

            self.camera.save_camera_input_to_file()
            self.camera.stop_camera_input()
            pixbuf = gtk.gdk.pixbuf_new_from_file_at_size(self.imagepath, w, h)
            try:
                array = pixbuf.get_pixels()
            except:
                array = None

        if array is not None:
            length = len(array) / 3
            r = 0
            g = 0
            b = 0
            i = 0
            for j in range(length):
                r += ord(array[i])
                i += 1
                g += ord(array[i])
                i += 1
                b += ord(array[i])
                i += 1
            if luminance_only:
                lum = int((r * 0.3 + g * 0.6 + b * 0.1) / length)
                self.update_label_value('luminance', lum)
                return lum
            else:
                self.heap.append(int((b / length)))
                self.heap.append(int((g / length)))
                self.heap.append(int((r / length)))
        else:
            if luminance_only:
                return -1
            else:
                self.heap.append(-1)
                self.heap.append(-1)
                self.heap.append(-1)

    def _get_volume(self):
        """ return mic in value """
        #TODO: Adjust gain for different HW
        buf = self.ringbuffer.read(None, self.input_step)
        if len(buf) > 0:
            volume = float(_avg(buf, abs_value=True))
            self.update_label_value('volume', volume)
            return volume
        else:
            return 0

    def _get_sound(self):
        """ return raw mic in value """
        buf = self.ringbuffer.read(None, self.input_step)
        if len(buf) > 0:
            sound = float(buf[0])
            self.update_label_value('sound', sound)
            return sound
        else:
            return 0

    def _get_pitch(self):
        """ return index of max value in fft of mic in values """
        buf = []
        for i in range(4):
            buf = append(buf, self.ringbuffer.read(None, self.input_step))
        if len(buf) > 0:
            r = []
            for j in rfft(buf):
                r.append(abs(j))
            # Convert output to Hertz
            pitch = r.index(max(r)) * 48000 / len(buf)
            self.update_label_value('pitch', pitch)
            return pitch
        else:
            return 0

    def _get_resistance(self):
        """ return resistance sensor value """
        buf = self.ringbuffer.read(None, self.input_step)
        if len(buf) > 0:
            # See <http://bugs.sugarlabs.org/ticket/552#comment:7>
            # TODO: test this calibration on XO 1.5
            if self.tw.hw == XO1:
                resistance = 2.718 ** ((float(_avg(buf)) * 0.000045788) + \
                                           8.0531)
            else:
                avg_buf = float(_avg(buf))
                if avg_buf > 0:
                    resistance = (420000000 / avg_buf) - 13500
                else:
                    resistance = 420000000
            self.update_label_value('resistance', resistance)
            return resistance
        else:
            return 0

    def _get_voltage(self):
        """ return voltage sensor value """
        buf = self.ringbuffer.read(None, self.input_step)
        if len(buf) > 0:
            # See <http://bugs.sugarlabs.org/ticket/552#comment:7>
            voltage = float(_avg(buf)) * self.voltage_gain + self.voltage_bias
            self.update_label_value('voltage', voltage)
            return voltage
        else:
            return 0

    # Depreciated block methods

    def _show_template1x1(self, title, media):
        """ title, one image, and description """
        xo = self.tw.calc_position('t1x1')[2]
        x = -(self.tw.canvas.width / 2) + xo
        y = self.tw.canvas.height / 2
        self.tw.canvas.setxy(x, y, pendown=False)
        # save the text size so we can restore it later
        save_text_size = self.tw.canvas.textsize
        # set title text
        self.tw.canvas.settextsize(self.title_height)
        self._show(title)
        # calculate and set scale for media blocks
        myscale = 45 * (self.tw.canvas.height - self.title_height * 2) \
                      / self.tw.canvas.height
        self._set_scale(myscale)
        # set body text size
        self.tw.canvas.settextsize(self.body_height)
        # render media object
        # leave some space below the title
        y -= int(self.title_height * 2 * self.tw.lead)
        self.tw.canvas.setxy(x, y, pendown=False)
        self._show(media)
        if self.tw.running_sugar:
            x = 0
            self.tw.canvas.setxy(x, y, pendown=False)
            self._show(media.replace('media_', 'descr_'))
        # restore text size
        self.tw.canvas.settextsize(save_text_size)

    def _show_template2x1(self, title, media1, media2):
        """ title, two images (horizontal), two descriptions """
        xo = self.tw.calc_position('t2x1')[2]
        x = -(self.tw.canvas.width / 2) + xo
        y = self.tw.canvas.height / 2
        self.tw.canvas.setxy(x, y, pendown=False)
        # save the text size so we can restore it later
        save_text_size = self.tw.canvas.textsize
        # set title text
        self.tw.canvas.settextsize(self.title_height)
        self._show(title)
        # calculate and set scale for media blocks
        myscale = 45 * (self.tw.canvas.height - self.title_height * 2) / \
                  self.tw.canvas.height
        self._set_scale(myscale)
        # set body text size
        self.tw.canvas.settextsize(self.body_height)
        # render four quadrents
        # leave some space below the title
        y -= int(self.title_height * 2 * self.tw.lead)
        self.tw.canvas.setxy(x, y, pendown=False)
        self._show(media1)
        x = 0
        self.tw.canvas.setxy(x, y, pendown=False)
        self._show(media2)
        y = -self.title_height
        if self.tw.running_sugar:
            self.tw.canvas.setxy(x, y, pendown=False)
            self._show(media2.replace('media_', 'descr_'))
            x = -(self.tw.canvas.width / 2) + xo
            self.tw.canvas.setxy(x, y, pendown=False)
            self._show(media1.replace('media_', 'descr_'))
        # restore text size
        self.tw.canvas.settextsize(save_text_size)

    def _show_bullets(self, sarray):
        """ title and varible number of  bullets """
        xo = self.tw.calc_position('bullet')[2]
        x = -(self.tw.canvas.width / 2) + xo
        y = self.tw.canvas.height / 2
        self.tw.canvas.setxy(x, y, pendown=False)
        # save the text size so we can restore it later
        save_text_size = self.tw.canvas.textsize
        # set title text
        self.tw.canvas.settextsize(self.title_height)
        self._show(sarray[0])
        # set body text size
        self.tw.canvas.settextsize(self.bullet_height)
        # leave some space below the title
        y -= int(self.title_height * 2 * self.tw.lead)
        for s in sarray[1:]:
            self.tw.canvas.setxy(x, y, pendown=False)
            self._show(s)
            y -= int(self.bullet_height * 2 * self.tw.lead)
        # restore text size
        self.tw.canvas.settextsize(save_text_size)

    def _show_template1x2(self, title, media1, media2):
        """ title, two images (vertical), two desciptions """
        xo = self.tw.calc_position('t1x2')[2]
        x = -(self.tw.canvas.width / 2) + xo
        y = self.tw.canvas.height / 2
        self.tw.canvas.setxy(x, y, pendown=False)
        # save the text size so we can restore it later
        save_text_size = self.tw.canvas.textsize
        # set title text
        self.tw.canvas.settextsize(self.title_height)
        self._show(title)
        # calculate and set scale for media blocks
        myscale = 45 * (self.tw.canvas.height - self.title_height * 2) / \
                 self.tw.canvas.height
        self._set_scale(myscale)
        # set body text size
        self.tw.canvas.settextsize(self.body_height)
        # render four quadrents
        # leave some space below the title
        y -= int(self.title_height * 2 * self.tw.lead)
        self.tw.canvas.setxy(x, y, pendown=False)
        self._show(media1)
        if self.tw.running_sugar:
            x = 0
            self.tw.canvas.setxy(x, y, pendown=False)
            self._show(media1.replace('media_', 'descr_'))
            y = -self.title_height
            self.tw.canvas.setxy(x, y, pendown=False)
            self._show(media2.replace('media_', 'descr_'))
            x = -(self.tw.canvas.width / 2) + xo
            self.tw.canvas.setxy(x, y, pendown=False)
            self._show(media2)
        # restore text size
        self.tw.canvas.settextsize(save_text_size)

    def _show_template2x2(self, title, media1, media2, media3, media4):
        """ title and four images """
        xo = self.tw.calc_position('t2x2')[2]
        x = -(self.tw.canvas.width / 2) + xo
        y = self.tw.canvas.height / 2
        self.tw.canvas.setxy(x, y, pendown=False)
        # save the text size so we can restore it later
        save_text_size = self.tw.canvas.textsize
        # set title text
        self.tw.canvas.settextsize(self.title_height)
        self._show(title)
        # calculate and set scale for media blocks
        myscale = 45 * (self.tw.canvas.height - self.title_height * 2) / \
                  self.tw.canvas.height
        self._set_scale(myscale)
        # set body text size
        self.tw.canvas.settextsize(self.body_height)
        # render four quadrents
        # leave some space below the title
        y -= int(self.title_height * 2 * self.tw.lead)
        self.tw.canvas.setxy(x, y, pendown=False)
        self._show(media1)
        x = 0
        self.tw.canvas.setxy(x, y, pendown=False)
        self._show(media2)
        y = -self.title_height
        self.tw.canvas.setxy(x, y, pendown=False)
        self._show(media4)
        x = -(self.tw.canvas.width / 2) + xo
        self.tw.canvas.setxy(x, y, pendown=False)
        self._show(media3)
        # restore text size
        self.tw.canvas.settextsize(save_text_size)

    def _show_template1x1a(self, title, media1):
        """ title, one media object """
        xo = self.tw.calc_position('t1x1a')[2]
        x = -(self.tw.canvas.width / 2) + xo
        y = self.tw.canvas.height / 2
        self.tw.canvas.setxy(x, y, pendown=False)
        # save the text size so we can restore it later
        save_text_size = self.tw.canvas.textsize
        # set title text
        self.tw.canvas.settextsize(self.title_height)
        self._show(title)
        # calculate and set scale for media blocks
        myscale = 90 * (self.tw.canvas.height - self.title_height * 2) / \
                       self.tw.canvas.height
        self._set_scale(myscale)
        # set body text size
        self.tw.canvas.settextsize(self.body_height)
        # render media object
        # leave some space below the title
        y -= int(self.title_height * 2 * self.tw.lead)
        self.tw.canvas.setxy(x, y, pendown=False)
        self._show(media1)
        # restore text size
        self.tw.canvas.settextsize(save_text_size)

    def _write(self, string, fsize):
        """ Write string at size """
        x = self.tw.canvas.width / 2 + int(self.tw.canvas.xcor)
        y = self.tw.canvas.height / 2 - int(self.tw.canvas.ycor)
        self.tw.canvas.draw_text(string, x, y - 15, int(fsize),
                                 self.tw.canvas.width)