# Copyright (C) 2009, Chris Ball <chris@printf.net>
# Copyright (C) 2009, Benjamin M. Schwartz <bmschwar@fas.harvard.edu>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 3 of the License, or
# (at your option) any later version.
"""Arithmetic Activity: A quiz activity for arithmetic."""

from __future__ import with_statement
import sys, cgitb

cgitb.enable(format="plain")
cgitb.handler = sys.excepthook

import logging
import gtk
import pango
import random
import gobject
import math
import time
import os
import os.path
import hashlib
import groupthink
import groupthink.gtk_tools
import groupthink.sugar_tools

from gettext import gettext as _
from sugar.activity import activity
from sugar import profile

try:
    # 0.86+ toolbar widgets
    from sugar.activity.widgets import ActivityToolbarButton, StopButton
    from sugar.graphics.toolbarbox import ToolbarBox, ToolbarButton
    _USE_OLD_TOOLBARS = False
except ImportError:
    # Pre-0.86 toolbar widgets
    from sugar.activity.activity import ActivityToolbox
    _USE_OLD_TOOLBARS = True

def score_codec(score_or_opaque, pack_or_unpack):
    v = score_or_opaque
    if pack_or_unpack:
        return (v.cumulative_score, v.last_score, v.last_time)
    else:
        return ImmutableScore(cumulative_score=v[0],
                              last_score=v[1],
                              last_time=v[2],)

class ImmutableScore(object):
    """An immutable representation of scores suitable for synchronization
    through Groupthink. The codec function is named score_codec."""

    def __init__(self, old_score = None, cumulative_score=0, last_score=0, last_time=0.0):
        """Immutable objects may be constructed in absolute or relative terms.
        Absolute terms are used when old_score is None.
        Relative terms are used when old_score is an ImmutableScore.
        """
        attrs = [("cumulative_score", lambda a,b: a+b),
                 ("last_score", lambda a,b: b),
                 ("last_time", lambda a,b: b)]
        if old_score is not None:
            for a, u in attrs:
                setattr(self, '_'+a, u(getattr(old_score, a), locals()[a]))
        else:
            for a, u in attrs:
                setattr(self, '_'+a, locals()[a])

    def _get_cumulative_score(self):
        return self._cumulative_score
    cumulative_score = property(_get_cumulative_score)

    def _get_last_score(self):
        return self._last_score
    last_score = property(_get_last_score)

    def _get_last_time(self):
        return self._last_time
    last_time = property(_get_last_time)

class ArithmeticActivity(groupthink.sugar_tools.GroupActivity):
    """Arithmetic Activity as specified in activity.info"""
    DIFFICULTY_EASY     = False
    DIFFICULTY_MEDIUM   = False
    DIFFICULTY_HARD     = False

    def __init__(self, handle):
        super(ArithmeticActivity, self).__init__(handle)

        self._configure_toolbars()

    def _configure_toolbars(self):
        if _USE_OLD_TOOLBARS:
            toolbox = ActivityToolbox(self)
            toolbar = gtk.Toolbar()
        else:
            toolbar_box = ToolbarBox()
            toolbar = toolbar_box.toolbar

            activity_button = ActivityToolbarButton(self)
            toolbar_box.toolbar.insert(activity_button, 0)
            activity_button.show()

            self._add_expander(toolbar_box.toolbar)

            toolbar.add(gtk.SeparatorToolItem())

        if _USE_OLD_TOOLBARS:
            toolbox.add_toolbar(_("Game"), toolbar)
            toolbox.set_current_toolbar(1)

            self.set_toolbox(toolbox)
            toolbox.show()
        else:
            stop_button = StopButton(self)
            stop_button.props.accelerator = '<Ctrl><Shift>Q'
            toolbar_box.toolbar.insert(stop_button, -1)
            stop_button.show()

            self.set_toolbar_box(toolbar_box)
            toolbar_box.show()

    def _add_expander(self, toolbar):
        """Insert a toolbar item which will expand to fill the available
        space."""
        separator = gtk.SeparatorToolItem()
        separator.props.draw = False
        separator.set_expand(True)
        toolbar.insert(separator, -1)
        separator.show()

    def _get_period(self):
        try:
            period = self.cloud.periodentry.get_text()
            period = int(period)
        except:
            period = 10
        return period

    period = property(_get_period)

    def initialize_display(self):
        """Set up the Arithmetic activity."""
        self._logger = logging.getLogger('arithmetic-activity')
        self.starttime = 0
        self.endtime = 0
        self.secondsleft = ""
        self.question = ""
        self.answer = ""
        self.cloud.scoreboard = groupthink.CausalDict(value_translator=score_codec)
        self.scoreboard = self.cloud.scoreboard
        self.mynickname = profile.get_nick_name()
        self.scoreboard[self.mynickname] = ImmutableScore()
        self._question_index = 0
        self._puzzle_hashes = set()
        self._puzzle_code = {}
        self._active_mode_hashes = set()

        # Main layout
        vbox = gtk.VBox()

        # Set a startpoint for a shared seed
        self.cloud.startpoint = groupthink.HighScore(self.timer.time(), 0)

        # Scoreboard
        scorebox = gtk.VBox()
        self.model = gtk.TreeStore(gobject.TYPE_STRING, # name
                                   gobject.TYPE_INT,    # last round score
                                   gobject.TYPE_INT,    # total score
                                   gobject.TYPE_FLOAT)  # time for last question
        self.treeview = treeview = gtk.TreeView(self.model)
        cellrenderer = gtk.CellRendererText()
        col1 = gtk.TreeViewColumn(_("Name"), cellrenderer, text=0)
        col2 = gtk.TreeViewColumn(_("Round score"), cellrenderer, text=1)
        col3 = gtk.TreeViewColumn(_("Total score"), cellrenderer, text=2)
        col4 = gtk.TreeViewColumn(_("Time for answering last question"), cellrenderer, text=3)
        treeview.append_column(col1)
        treeview.append_column(col2)
        treeview.append_column(col3)
        treeview.append_column(col4)

        my_score = self.scoreboard[self.mynickname]

        self.olditer = self.model.insert_before(None, None)
        self.model.set_value(self.olditer, 0, self.mynickname)
        self.model.set_value(self.olditer, 1, my_score.last_score)
        self.model.set_value(self.olditer, 2, my_score.cumulative_score)
        self.model.set_value(self.olditer, 3, my_score.last_time)
        treeview.expand_all()
        scorebox.pack_start(treeview)

        # Horizontal fields
        difficultybox = gtk.HBox()
        periodbox     = gtk.HBox()
        toprowbox     = gtk.HBox()
        modebox       = gtk.HBox()
        self.inner_modebox = gtk.HBox()
        questionbox   = gtk.HBox()
        answerbox     = gtk.HBox()
        decisionbox   = gtk.HBox()
        lastroundbox  = gtk.HBox()
        bottomrowbox  = gtk.HBox()
        countdownbox  = gtk.HBox()

        # Labels
        difficultylabel = gtk.Label("Difficulty: ")
        periodlabel     = gtk.Label("Period: ")
        periodunitslabel= gtk.Label(" sec  ")
        modelabel       = gtk.Label("Puzzles: ")
        questionlabel   = gtk.Label("Question: ")
        answerlabel     = gtk.Label("Answer: ")
        decisionlabel   = gtk.Label("You were: ")
        lastroundlabel  = gtk.Label("Last round: ")
        self.lastanswerlabel = gtk.Label("")
        self.countdownlabel = gtk.Label("Time until next question: ")

        # ToggleButtons for difficulty
        self.cloud.easytoggle      = groupthink.gtk_tools.SharedToggleButton("< 10")
        self.cloud.mediumtoggle    = groupthink.gtk_tools.SharedToggleButton("< 20")
        self.cloud.hardtoggle      = groupthink.gtk_tools.SharedToggleButton("< 50")

        self.cloud.easytoggle.set_active(False)
        self.cloud.mediumtoggle.set_active(False)
        self.cloud.hardtoggle.set_active(False)
        self.cloud.easytoggle.connect("toggled", self.easy_cb)
        self.cloud.mediumtoggle.connect("toggled", self.medium_cb)
        self.cloud.hardtoggle.connect("toggled", self.hard_cb)

        # Entry for puzzle period
        self.cloud.periodentry = groupthink.gtk_tools.RecentEntry(max=2)
        self.cloud.periodentry.modify_font(pango.FontDescription("Mono 14"))
        self.cloud.periodentry.set_text(str(self.period))
        self.cloud.periodentry.set_width_chars(2)
        self.cloud.periodentry.connect("changed", self._period_cb)

        # Puzzle generators
        self.cloud.puzzles         = groupthink.AddOnlySet()
        self.cloud.puzzles.register_listener(self.new_puzzles_cb)

        # Text entry box for question
        self.questionentry = gtk.TextView()
        self.questionentry.modify_font(pango.FontDescription("Mono 14"))
        self.questionentry.set_property("editable", False)

        # Text entry box for answer
        self.answerentry = gtk.Entry(max=50)
        self.answerentry.modify_font(pango.FontDescription("Sans 14"))
        self.answerentry.connect("activate", self.answer_cb)

        # Whether the user was correct
        self.decisionentry = gtk.Entry(max=50)
        self.decisionentry.modify_font(pango.FontDescription("Sans 14"))
        self.decisionentry.set_property("editable", False)

        # Packing
        difficultybox.pack_start(difficultylabel, expand=False)
        difficultybox.pack_start(self.cloud.easytoggle, expand=False)
        difficultybox.pack_start(self.cloud.mediumtoggle, expand=False)
        difficultybox.pack_start(self.cloud.hardtoggle, expand=False)

        periodbox.pack_start(periodlabel, expand=False)
        periodbox.pack_start(self.cloud.periodentry, expand=False)
        periodbox.pack_start(periodunitslabel, expand=False)

        toprowbox.pack_start(difficultybox, expand=False)
        toprowbox.pack_end(periodbox, expand=False)

        questionbox.pack_start(questionlabel, expand=False)
        questionbox.pack_start(self.questionentry)
        modebox.pack_start(modelabel, expand=False)
        modebox.pack_start(self.inner_modebox)
        answerbox.pack_start(answerlabel, expand=False)
        answerbox.pack_start(self.answerentry)
        decisionbox.pack_start(decisionlabel, expand=False)
        decisionbox.pack_start(self.decisionentry)

        lastroundbox.pack_start(lastroundlabel, expand=False)
        lastroundbox.pack_start(self.lastanswerlabel, expand=False)

        countdownbox.pack_start(self.countdownlabel, expand=False)

        bottomrowbox.pack_start(countdownbox)
        bottomrowbox.pack_end(lastroundbox)

        vbox.pack_start(toprowbox, expand=False)
        vbox.pack_start(modebox, expand=False)
        vbox.pack_start(questionbox, expand=False)
        vbox.pack_start(answerbox, expand=False)
        vbox.pack_start(decisionbox, expand=False)
        vbox.pack_start(countdownbox, expand=False)
        vbox.pack_start(bottomrowbox, expand=False)
        vbox.pack_start(scorebox)

        # Set defaults for questions.
        self.setup_puzzles()
        self.cloud.easytoggle.set_active(True)

        # Make a new question.
        self.generate_new_question()
        self.start_question()
        self.start_countdown()
        self.answerentry.grab_focus()
        self.lastanswerlabel.set_markup("")
        return vbox

    def when_initiating_sharing(self):
        self.cloud.startpoint.set_value(self.timer.time(), 1)

    def generate_new_question(self):
        # This requires a fairly large comment.
        #
        # There are at least two possible solutions to the problem of
        # trying to show the same questions on every client at (roughly)
        # the same time.  They are:
        #  1)  Share a random seed beforehand and draw questions from it,
        #      so that everyone gets the same questions.  Synchronize
        #      clocks to make sure that people are seeing the same
        #      questions at the same time, and establish that question N
        #      will start at time starttime + (period * N).  This requires a
        #      passable attempt at clock synchronization, but then the
        #      clients can cease communicating with each other (forever!)
        #      and still know what question to pop up when.
        #  2)  Nominate someone to choose the questions, and wait for
        #      messages from that person that tell you what the question
        #      is and when you should start it.  This requires a reliable
        #      network link with relatively low latency, and algorithms
        #      that can avoid races when people leave and rejoin a game.
        #
        # We decided to go for 1), using Groupthink to work out a shared
        # clock, stating that questions start every ten seconds, and
        # using a shared seed -- self.cloud.startpoint -- plus a question
        # index.
        t0 = self.cloud.startpoint.get_value()
        random.seed((t0, self._question_index))

        difficultylist = list()
        if self.DIFFICULTY_EASY:
            difficultylist.append("easy")
        if self.DIFFICULTY_MEDIUM:
            difficultylist.append("medium")
        if self.DIFFICULTY_HARD:
            difficultylist.append("hard")

        # This requires a fairly large comment.
        if len(self._active_mode_hashes) > 0 and len(difficultylist) > 0:
            mode = random.choice(list(self._active_mode_hashes))
            difficulty = random.choice(difficultylist)
            self.question, self.answer = self.generate_problem(mode, difficulty)
        else:
            self.inner_modebox.get_children()[0].set_active(True)
            self.question = self.answer = ""

    def generate_problem(self, mode, difficulty):
        mode_dict = self._puzzle_code[mode]
        get_problem = mode_dict['get_problem']
        return get_problem(self, difficulty)

    def generate_number(self, difficulty, lessthan=0):
        if difficulty == "easy":
            return random.randint(1, lessthan or 9)
        if difficulty == "medium":
            return random.randint(1, lessthan or 19)
        if difficulty == "hard":
            return random.randint(1, lessthan or 50)
        else:
            raise AssertionError

    def solve (self, answer, incorrect=False):
        try:
            answer = int(answer)
        except ValueError:
            self.answerentry.set_text("")
            self.decisionentry.set_text("")
            return

        self.endtime = time.time()
        self.model.set_value(self.olditer, 3, self.endtime - self.starttime)

        if int(answer) == int(self.answer):
            self.answercorrect = True
            self.decisionentry.set_text("Correct!")
            old_score = self.scoreboard[self.mynickname]
            new_score = ImmutableScore(old_score=old_score,
                                       cumulative_score=1,
                                       last_score=1,
                                       last_time=self.endtime - self.starttime,)
            self.scoreboard[self.mynickname] = new_score
        else:
            self.answercorrect = False
            self.decisionentry.set_text("Not correct")

    # Callbacks.
    def _period_cb(self, _):
        try:
            period = self.cloud.periodentry.get_text()
            period = int(period)
            if   period < 1:  self.cloud.periodentry.set_text("10")
            elif period > 99: self.cloud.periodentry.set_text("60")
        except:
            pass

    def answer_cb(self, answer, incorrect=False):
        self.answergiven = True
        self.solve(self.answerentry.get_text())

    def start_countdown(self):
        self.secondsleft = self.period
        gobject.timeout_add(1000, self.onesecond_cb)
        self.countdownlabel.set_markup('Time until next question: <span size="xx-large">%s</span>s' % self.secondsleft)

    def onesecond_cb(self):
        elapsed_time = self.timer.time() - self.cloud.startpoint.get_value()
        curr_index = int(math.floor(elapsed_time/self.period))
        time_to_next = self.period - (elapsed_time - (self.period*curr_index))
        self.secondsleft = int(math.ceil(time_to_next))
        self.countdownlabel.set_markup('Time until next question: <span size="xx-large">%s</span>s' % self.secondsleft)
        if curr_index != self._question_index:
            self._question_index = curr_index
            if self.answergiven == False:
                self.solve("")
            self.start_question()
            self.answerentry.set_text("")

        self.model = gtk.TreeStore(gobject.TYPE_STRING, # name
                                   gobject.TYPE_INT,    # last round score
                                   gobject.TYPE_INT,    # total score
                                   gobject.TYPE_FLOAT)  # time for last question

        for person, score in self.scoreboard.iteritems():
            self.model.append(None, (person, score.last_score, score.cumulative_score, score.last_time))

        self.treeview.set_model(self.model)
        return True

    def start_question(self):
        old_answer = self.answer
        old_question = self.question.replace("\n", "  ")
        old_answergiven = getattr(self, "answergiven", False)
        old_answercorrect = getattr(self, "answercorrect", False)

        self.starttime = time.time()
        self.generate_new_question()
        self.questionentry.get_buffer().set_text(self.question)
        self.answergiven = False
        self.answercorrect = False
        self.answerentry.set_text("")
        self.decisionentry.set_text("")

        if self.cloud.periodentry.get_text() != str(self.secondsleft):
            self.cloud.periodentry.set_text(str(self.period))

        markup = "%s : <span weight=\"bold\" color=\"%s\">%s</span>" % (
            old_question,
            old_answercorrect and "blue" or "black",
            old_answer)
        self.lastanswerlabel.set_markup(markup.strip())


    def easy_cb(self, toggled):
        self.DIFFICULTY_EASY = toggled.get_active()
        self.answerentry.grab_focus()

    def medium_cb(self, toggled):
        self.DIFFICULTY_MEDIUM = toggled.get_active()
        self.answerentry.grab_focus()

    def hard_cb(self, toggled):
        self.DIFFICULTY_HARD = toggled.get_active()
        self.answerentry.grab_focus()

    def puzzle_toggle_cb(self, toggled, puzzle_hash):
        if toggled.get_active():
            self._active_mode_hashes.add(puzzle_hash)
        else:
            self._active_mode_hashes.remove(puzzle_hash)
        if hasattr(self, 'answerentry'):
            self.answerentry.grab_focus()

    def setup_puzzles(self):
        puzzle_names = os.listdir("puzzles")
        puzzle_names.sort()
        for name in puzzle_names:
            if name.endswith(".py"):
                path = os.path.join("puzzles", name)
                with open(path, 'r') as file:
                    text = file.read()
                    self.cloud.puzzles.add(text)
                    self.new_puzzles_cb(set([text]))
        self.start_question()
        self.start_countdown()

    def new_puzzles_cb(self, puzzles):
        for text in puzzles:
            if text.strip() == '':
                continue

            md = hashlib.sha1()
            md.update(text)
            hash = md.digest().encode("hex")

            if hash not in self._puzzle_hashes:
                self._puzzle_hashes.add(hash)

                env_global = {}
                env_local = {}
                exec text in env_global, env_local

                togglename = hash + "_toggle"
                self.cloud[togglename] = groupthink.gtk_tools.SharedToggleButton(' ' + env_local['name'] + ' ')
                self.cloud[togglename].set_active(False)
                self.cloud[togglename].connect("toggled", self.puzzle_toggle_cb, hash)
                self.cloud[togglename].sort_key = env_local['sort_key']

                self._puzzle_code[hash] = env_local

                kids = self.inner_modebox.get_children()
                old_size = len(kids)

                for kid in kids:
                    self.inner_modebox.remove(kid)

                kids.append(self.cloud[togglename])

                kids.sort(key=lambda x: x.sort_key)

                for kid in kids:
                    self.inner_modebox.pack_start(kid, expand=False)