# Copyright (c) 2019 lulua contributors
# 
# 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 sys, operator, pickle, argparse, logging, yaml, math, time
from operator import itemgetter
from itertools import chain, groupby, product
from collections import defaultdict
from io import StringIO

from .layout import *
from .keyboard import defaultKeyboards
from .writer import SkipEvent, Writer
from .carpalx import Carpalx, models
from .plot import letterfreq, triadfreq
from .util import displayText

def updateDictOp (a, b, op):
    """ Update dict a by adding items from b using op """
    for k, v in b.items ():
        if k not in a:
            # simple
            a[k] = v
        else:
            if isinstance (v, dict):
                # recursive
                assert isinstance (a[k], dict)
                updateDictOp (a[k], v, op)
            elif isinstance (v, list):
                assert False
            else:
                a[k] = op (a[k], v)

class Stats:
    name = 'invalid'

    def process (self, event):
        raise NotImplementedError

    def update (self, other):
        raise NotImplementedError

class RunlenStats (Stats):
    __slots__ = ('lastHand', 'perHandRunlenDist', 'curPerHandRunlen',
            'fingerRunlen', 'lastFinger', 'fingerRunlenDist', 'writer')

    name = 'runlen'

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

        self.lastHand = None
        self.perHandRunlenDist = dict ((x, defaultdict (int)) for x in Direction)
        self.curPerHandRunlen = 0

        self.lastFinger = None
        self.fingerRunlenDist = dict (((x, y), defaultdict (int)) for x, y in product (iter (Direction), iter (FingerType)))
        self.fingerRunlen = 0

    def __eq__ (self, other):
        if not isinstance (other, RunlenStats):
            return NotImplemented
        return self.perHandRunlenDist == other.perHandRunlenDist
        
    def process (self, event):
        if isinstance (event, ButtonCombination):
            assert len (event.buttons) == 1
            thisHand, thisFinger = self.writer.getHandFinger (first (event.buttons))
            if self.lastHand and thisHand != self.lastHand:
                self.perHandRunlenDist[self.lastHand][self.curPerHandRunlen] += 1
                self.curPerHandRunlen = 0
            self.curPerHandRunlen += 1
            self.lastHand = thisHand

            fingerKey = (thisHand, thisFinger)
            if self.lastFinger and fingerKey != self.lastFinger:
                self.fingerRunlenDist[fingerKey][self.fingerRunlen] += 1
                self.fingerRunlen = 0
            self.fingerRunlen += 1
            self.lastFinger = fingerKey
        elif isinstance (event, SkipEvent):
            # reset state, we don’t know which button to press
            self.lastHand = None
            self.curPerHandRunlen = 0

            self.lastFinger = None
            self.fingerRunlen = 0
        else:
            raise ValueError ()

    def update (self, other):
        updateDictOp (self.perHandRunlenDist, other.perHandRunlenDist, operator.add)

class SimpleStats (Stats):
    __slots__ = ('buttons', 'combinations', 'unknown')

    name = 'simple'
    
    def __init__ (self, writer):
        # single buttons
        self.buttons = defaultdict (int)
        # button combinations
        self.combinations = defaultdict (int)
        self.unknown = defaultdict (int)

    def __eq__ (self, other):
        if not isinstance (other, SimpleStats):
            return NotImplemented
        return self.buttons == other.buttons and \
                self.combinations == other.combinations and \
                self.unknown == other.unknown

    def process (self, event):
        if isinstance (event, SkipEvent):
            self.unknown[event.char] += 1
        elif isinstance (event, ButtonCombination):
            for b in event:
                self.buttons[b] += 1
            self.combinations[event] += 1
        else:
            raise ValueError ()

    def update (self, other):
        updateDictOp (self.buttons, other.buttons, operator.add)
        updateDictOp (self.combinations, other.combinations, operator.add)
        updateDictOp (self.unknown, other.unknown, operator.add)

class TriadStats (Stats):
    """
    Button triad stats with an overlap of two.

    Whitespace buttons are ignored.
    """

    __slots__ = ('_triad', 'triads', '_writer', '_ignored')

    name = 'triads'

    def __init__ (self, writer):
        self._writer = writer

        self._triad = []
        self.triads = defaultdict (int)
        keyboard = self._writer.layout.keyboard
        self._ignored = frozenset (keyboard[x] for x in ('Fl_space', 'Fr_space', 'CD_ret', 'Cl_tab'))

    def __eq__ (self, other):
        if not isinstance (other, TriadStats):
            return NotImplemented
        return self.triads == other.triads

    def process (self, event):
        if isinstance (event, SkipEvent):
            # reset
            self._triad = []
        elif isinstance (event, ButtonCombination):
            assert len (event.buttons) == 1
            btn = first (event.buttons)
            if btn not in self._ignored:
                self._triad.append (event)

                if len (self._triad) > 3:
                    self._triad = self._triad[1:]
                    assert len (self._triad) == 3
                if len (self._triad) == 3:
                    k = tuple (self._triad)
                    self.triads[k] += 1
        else:
            raise ValueError ()

    def update (self, other):
        updateDictOp (self.triads, other.triads, operator.add)

class WordStats (Stats):
    """
    Word stats
    """

    __slots__ = ('words', '_currentWord', '_writer')

    name = 'words'

    def __init__ (self, writer):
        self._writer = writer

        self._currentWord = []
        self.words = defaultdict (int)

    def __eq__ (self, other):
        if not isinstance (other, WordStats):
            return NotImplemented
        return self.words == other.words

    def process (self, event):
        if isinstance (event, SkipEvent):
            # reset
            self._currentWord = []
        elif isinstance (event, ButtonCombination):
            text = self._writer.layout.getText (event)
            for t in text:
                cat = unicodedata.category (t)
                if cat in {'Lo', 'Mn'}:
                    # arabic letter or diacritic (non-spacing mark), everything
                    # else is considered a word-delimiter
                    self._currentWord.append (t)
                elif self._currentWord:
                    self.words[''.join (self._currentWord)] += 1
                    self._currentWord = []
        else:
            raise ValueError ()

    def update (self, other):
        updateDictOp (self.words, other.words, operator.add)

allStats = [SimpleStats, RunlenStats, TriadStats, WordStats]

def unpickleAll (fd):
    while True:
        try:
            yield pickle.load (fd)
        except EOFError:
            break

def makeCombined (keyboard):
    """ Create a dict which contains initialized stats, ready for combining (not actual writing!) """
    layout = defaultLayouts['null'].specialize (keyboard)
    w = Writer (layout)
    return dict ((cls.name, cls(w)) for cls in allStats)

def combine (args):
    keyboard = defaultKeyboards[args.keyboard]
    combined = makeCombined (keyboard)
    for r in unpickleAll (sys.stdin.buffer):
        for s in allStats:
            combined[s.name].update (r[s.name])
    pickle.dump (combined, sys.stdout.buffer, pickle.HIGHEST_PROTOCOL)

def pretty (args):
    stats = pickle.load (sys.stdin.buffer)

    keyboard = defaultKeyboards[args.keyboard]
    layout = defaultLayouts[args.layout].specialize (keyboard)
    writer = Writer (layout)

    buttonPresses = sum (stats['simple'].buttons.values ())
    print ('button presses', buttonPresses)
    for k, v in sorted (stats['simple'].buttons.items (), key=itemgetter (1)):
        print (f'{k} {v:10d} {v/buttonPresses*100:5.1f}%')

    combinationTotal = sum (stats['simple'].combinations.values ())
    items = stats['simple'].combinations.items ()
    n = len (items)
    print ('combinations', combinationTotal)
    for i, (k, v) in enumerate (sorted (items, key=itemgetter (1))):
        t = displayText (layout.getText (k))
        print (f'{n-i: 3d}. {t:4s} {k} {v:10d} {v/combinationTotal*100:7.3f}%')

    print ('unknown')
    for k, v in sorted (stats['simple'].unknown.items (), key=itemgetter (1)):
        print (f'{k!r} {v:10d}')

    combined = defaultdict (int)
    for hand, dist in stats['runlen'].perHandRunlenDist.items ():
        print (hand)
        total = sum (dist.values ())
        for k, v in sorted (dist.items (), key=itemgetter (0)):
            print (f'{k:2d} {v:10d} {v/total*100:5.1f}%')
            combined[k] += v
    print ('combined')
    total = sum (combined.values ())
    for k, v in combined.items ():
        print (f'{k:2d} {v:10d} {v/total*100:5.1f}%')

    print ('triads')
    for triad, count in sorted (stats['triads'].triads.items (), key=itemgetter (1)):
        print (f'{triad} {count:10d}')

    totalWords = sum (stats['words'].words.values ())
    print ('words', totalWords)
    for word, count in sorted (stats['words'].words.items (), key=itemgetter (1)):
        print (f'{word:20s} {count/totalWords*100:2.5f} {count:10d}')

    effort = Carpalx (models['mod01'], writer)
    effort.addTriads (stats['triads'].triads)
    print ('total effort (carpalx)', effort.effort)

def keyHeatmap (args):
    stats = pickle.load (sys.stdin.buffer)

    keyboard = defaultKeyboards[args.keyboard]
    layout = defaultLayouts[args.layout].specialize (keyboard)
    writer = Writer (layout)

    buttons = {}
    buttonPresses = sum (stats['simple'].buttons.values ())
    data = {'total': buttonPresses, 'buttons': buttons}
    for k, v in sorted (stats['simple'].buttons.items (), key=itemgetter (1)):
        assert k.name not in data
        buttons[k.name] = v
    yaml.dump (data, sys.stdout)

def sentenceStats (keyboard, layout, text):
    """
    Calculate effort for every character (button) in a text
    """

    writer = Writer (layout)
   
    effort = Carpalx (models['mod01'], writer)
    _ignored = frozenset (keyboard[x] for x in ('Fl_space', 'Fr_space', 'CD_ret', 'Cl_tab'))
    writtenText = []
    skipped = 0
    for match, event in writer.type (StringIO (text)):
        if isinstance (event, SkipEvent):
            skipped += 1
            writtenText.append ([event.char, None, 0])
        if not isinstance (event, ButtonCombination):
            continue

        writtenText.append ([match, event, 0])

        triad = list (filter (lambda x: x[1] is not None and first (x[1].buttons) not in _ignored, writtenText))[-3:]
        if len (triad) == 3:
            matchTriad, buttonTriad, _ = zip (*triad)
            triadEffort = effort._triadEffort (tuple (buttonTriad))

            # now walk the existing text backwards to find the original matches and add the computed effort
            writtenTextIt = iter (reversed (writtenText))
            matchTriad = list (matchTriad)
            while matchTriad:
                t = next (writtenTextIt)
                if t[0] == matchTriad[-1]:
                    matchTriad.pop ()
                    t[2] += triadEffort

            effort.addTriad (buttonTriad, 1)

    # normalize efforts to [0, 1]
    s = max (map (lambda x: x[2], writtenText))
    writtenText = list (map (lambda x: (x[0], x[2]/s if x[1] is not None else None), writtenText))
    return (writtenText, effort.effort, skipped)

from .text import mapChars, charMap

def layoutstats (args):
    """
    Statistics for the report
    """
    stats = pickle.load (sys.stdin.buffer)

    keyboard = defaultKeyboards[args.keyboard]
    layout = defaultLayouts[args.layout].specialize (keyboard)
    writer = Writer (layout)

    hands = defaultdict (int)
    fingers = defaultdict (int)
    buttonPresses = sum (stats['simple'].buttons.values ())
    for btn, count in stats['simple'].buttons.items ():
        hand, finger = writer.getHandFinger (btn)
        hands[hand] += count
        fingers[(hand, finger)] += count

    asymmetry = hands[LEFT]/buttonPresses - hands[RIGHT]/buttonPresses

    sentences = [
        'أَوْ كَصَيِّبٍ مِّنَ السَّمَاءِ فِيهِ ظُلُمَاتٌ وَرَعْدٌ وَبَرْقٌ يَجْعَلُونَ أَصَابِعَهُمْ فِي آذَانِهِم مِّنَ الصَّوَاعِقِ حَذَرَ الْمَوْتِ وَاللَّهُ مُحِيطٌ بِالْكَافِرِينَ',
        'اللغة العربية هي أكثرُ اللغاتِ السامية تحدثاً، وإحدى أكثر اللغات انتشاراً في العالم، يتحدثُها أكثرُ من 467 مليون نسمة.',
        ]
    sentences = [sentenceStats (keyboard, layout, mapChars (s, charMap).replace ('\r\n', '\n')) for s in sentences]

    pickle.dump (dict (
            layout=args.layout,
            hands=dict (hands),
            fingers=dict (fingers),
            buttonPresses=buttonPresses,
            asymmetry=asymmetry,
            sentences=sentences,
            ), sys.stdout.buffer)

def latinImeDict (args):
    """
    Create a dictionary for Android’s LatinIME input method from WordStats

    see https://android.googlesource.com/platform/packages/inputmethods/LatinIME/+/master/dictionaries/sample.combined
    """

    def f (p):
        """
        Word probability to logarithmic f-value.

        p = 1/(1.15^(255-f))
        """
        return 255+int (round (math.log (p, 1.15)))

    stats = pickle.load (sys.stdin.buffer)
    now = int (round (time.time ()))

    print ('# auto-generated by ' + __package__)
    print (f'dictionary=main:ar,locale=ar,description=Arabic wordlist,date={now},version=1')
    total = sum (stats['words'].words.values ())
    for word, count in sorted (stats['words'].words.items (), key=itemgetter (1), reverse=True):
        p = count/total
        print (f' word={word},f={f(p)}')

def corpusStats (args):
    """ Get corpus stats from stat files """
    stats = pickle.load (sys.stdin.buffer)
    meta = yaml.safe_load (args.metadata)

    meta['stats'] = dict (characters=sum (stats['simple'].combinations.values ()),
            words=sum (stats['words'].words.values ()))

    yaml.dump (meta, sys.stdout)
    # make document concatable
    print ('---')


def main ():
    parser = argparse.ArgumentParser(description='Process statistics files.')
    parser.add_argument('-l', '--layout', metavar='LAYOUT', help='Keyboard layout name')
    parser.add_argument('-k', '--keyboard', metavar='KEYBOARD',
            default='ibmpc105', help='Physical keyboard name')
    subparsers = parser.add_subparsers()
    sp = subparsers.add_parser('pretty')
    sp.set_defaults (func=pretty)
    sp = subparsers.add_parser('combine')
    sp.set_defaults (func=combine)
    sp = subparsers.add_parser('letterfreq')
    sp.set_defaults (func=letterfreq)
    sp = subparsers.add_parser('triadfreq')
    sp.add_argument('-c', '--cutoff', type=float, default=0.5, help='Only include the top x% of all triads')
    sp.add_argument('-r', '--reverse', action='store_true', help='Reverse sorting order')
    sp.add_argument('-s', '--sort', choices={'weight', 'effort', 'combined'}, default='weight', help='Sorter')
    sp.add_argument('-n', '--limit', type=int, default=0, help='Sorter')
    sp.set_defaults (func=triadfreq)
    sp = subparsers.add_parser('keyheatmap')
    sp.set_defaults (func=keyHeatmap)
    sp = subparsers.add_parser('layoutstats')
    sp.set_defaults (func=layoutstats)
    sp = subparsers.add_parser('latinime')
    sp.set_defaults (func=latinImeDict)
    sp = subparsers.add_parser('corpusstats')
    sp.add_argument('metadata', type=argparse.FileType ('r'))
    sp.set_defaults (func=corpusStats)

    logging.basicConfig (level=logging.INFO)
    args = parser.parse_args()

    return args.func (args)