#!/usr/bin/env python3

import argparse
import colorsys
import gettext
import json
import logging
import math
import sys
import xml.dom.minidom


gettext.install('messages', 'locale')


def ProcessComments(comments, f, width, height, bottomReserved, fontface, fontsize, alpha, lifetime, reduced):
    WriteASSHead(f, width, height, fontface, fontsize, alpha)
    rows = [[None]*(height-bottomReserved), [None]*(height-bottomReserved), [None]*(height-bottomReserved)]
    for i in comments:
        row = 0
        rowmax = height-bottomReserved-i[7]
        while row < rowmax:
            freerows = TestFreeRows(rows, i, row, width, height, bottomReserved, lifetime)
            if freerows >= i[7]:
                MarkCommentRow(rows, i, row)
                WriteComment(f, i, row, width, height, bottomReserved, fontsize, lifetime)
                break
            else:
                row += freerows or 1
        else:
            if not reduced:
                row = FindAlternativeRow(rows, i, height, bottomReserved)
                MarkCommentRow(rows, i, row)
                WriteComment(f, i, row, width, height, bottomReserved, fontsize, lifetime)


def TestFreeRows(rows, c, row, width, height, bottomReserved, lifetime):
    res = 0
    rowmax = height-bottomReserved-c[7]
    while row < rowmax and res < c[7]:
        if c[4] in (1, 2):
            if rows[c[4]][row] and rows[c[4]][row][0]+lifetime > c[0]:
                break
        else:
            if rows[c[4]][row] and rows[c[4]][row][0]+lifetime*(rows[c[4]][row][8]+c[8])/width > c[0]:
                break
        row += 1
        res += 1
    return res


def FindAlternativeRow(rows, c, height, bottomReserved):
    res = 0
    for row in range(height-bottomReserved-math.ceil(c[7])):
        if not rows[c[4]][row]:
            return row
        elif rows[c[4]][row][1] < rows[c[4]][res][1]:
            res = row
    return res


def MarkCommentRow(rows, c, row):
    try:
        for i in range(row, row+math.ceil(c[7])):
            rows[c[4]][i] = c
    except IndexError:
        pass


def WriteComment(f, c, row, width, height, bottomReserved, fontsize, lifetime):
    text = c[3].replace('\\', '\\\\').replace('\n', '\\N')
    if c[4] == 1:
        styles = '{\\an8}{\\pos(%(halfwidth)s, %(row)s)}' % {'halfwidth': round(width/2), 'row': row}
    elif c[4] == 2:
        styles = '{\\an2}{\\pos(%(halfwidth)s, %(row)s)}' % {'halfwidth': round(width/2), 'row': ConvertType2(row, height, bottomReserved)}
    else:
        styles = '{\\move(%(width)s, %(row)s, %(neglen)s, %(row)s)}' % {'width': width, 'row': row, 'neglen': -math.ceil(c[8])}
    if not (-1 < c[6]-fontsize < 1):
        styles += '{\\fs%s}' % round(c[6])
    if c[5] != 0xffffff:
        styles += '{\\c&H%02X%02X%02x&}' % (c[5]&0xff, (c[5]>>8)&0xff, (c[5]>>16)&0xff)
        if c[5] == 0x000000:
            styles += '{\\3c&HFFFFFF&}'
    f.write('Dialogue: 3,%(start)s,%(end)s,Default,,0000,0000,0000,,%(styles)s%(text)s\n' % {'start': ConvertTimestamp(c[0]), 'end': ConvertTimestamp(c[0]+lifetime), 'styles': styles, 'text': text})


def ProbeCommentFormat(f):
    f.seek(0)
    tmp = f.read(1)
    if tmp == '[':
        f.seek(0)
        return 'Acfun'
    elif tmp == '<':
        tmp = f.read(39)
        f.seek(0)
        if tmp == '?xml version="1.0" encoding="UTF-8"?><p':
            return 'Niconico'
        elif tmp == '?xml version="1.0" encoding="UTF-8"?><i':
            return 'Bilibili'
        else:
            return None
    else:
        f.seek(0)
        return None


NiconicoColorMap = {'red': 0xff0000, 'pink': 0xff8080, 'orange': 0xffc000, 'yellow': 0xffff00, 'green': 0x00ff00, 'cyan': 0x00ffff, 'blue': 0x0000ff, 'purple': 0xc000ff, 'black': 0x000000}


def ReadCommentsNiconico(f, fontsize):
    'Output format: [(timeline, timestamp, no, comment, pos, color, size, height, width)]'
    dom = xml.dom.minidom.parse(f)
    comment_element = dom.getElementsByTagName('chat')
    for comment in comment_element:
        try:
            c = str(comment.childNodes[0].wholeText)
            pos = 0
            color = 0xffffff
            size = fontsize
            for mailstyle in str(comment.getAttribute('mail')).split():
                if mailstyle == 'ue':
                    pos = 1
                elif mailstyle == 'shita':
                    pos = 2
                elif mailstyle == 'big':
                    size = fontsize*1.44
                elif mailstyle == 'small':
                    size = fontsize*0.64
                elif mailstyle in NiconicoColorMap:
                    color = NiconicoColorMap[mailstyle]
            yield (max(int(comment.getAttribute('vpos')), 0)*0.01, int(comment.getAttribute('date')), int(comment.getAttribute('no')), c, pos, color, size, (c.count('\n')+1)*size, CalculateLength(c)*size)
        except (AssertionError, AttributeError, IndexError, TypeError, ValueError):
            logging.warning(_('Invalid comment: %s') % comment.toxml())
            continue


def ReadCommentsAcfun(f, fontsize):
    'Output format: [(timeline, timestamp, no, comment, pos, color, size, height, width)]'
    comment_element = json.load(f)
    i = 0
    for comment in comment_element:
        try:
            p = str(comment['c']).split(',')
            assert len(p) >= 6
            assert p[2] in ('1', '2', '4', '5')
            c = str(comment['m'])
            size = int(p[3])*fontsize/25.0
            yield (float(p[0]), int(p[5]), i, c, {'1': 0, '2': 0, '4': 2, '5': 1}[p[2]], int(p[1]), size, (c.count('\n')+1)*size, CalculateLength(c)*size)
            i += 1
        except (AssertionError, AttributeError, IndexError, TypeError, ValueError):
            logging.warning(_('Invalid comment: %r') % comment)
            continue


def ReadCommentsBilibili(f, fontsize):
    'Output format: [(timeline, timestamp, no, comment, pos, color, size, height, width)]'
    dom = xml.dom.minidom.parse(f)
    comment_element = dom.getElementsByTagName('d')
    i = 0
    for comment in comment_element:
        try:
            p = str(comment.getAttribute('p')).split(',')
            assert len(p) >= 8
            assert p[1] in ('1', '4', '5')
            c = str(comment.childNodes[0].wholeText).replace('/n', '\\n')
            size = int(p[2])*fontsize/25.0
            yield (float(p[0]), int(p[4]), i, c, {'1': 0, '4': 2, '5': 1}[p[1]], int(p[3]), size, (c.count('\n')+1)*size, CalculateLength(c)*size)
            i += 1
        except (AssertionError, AttributeError, IndexError, TypeError, ValueError):
            logging.warning(_('Invalid comment: %s') % comment.toxml())
            continue


def ConvertTimestamp(timestamp):
    hour, minute = divmod(timestamp, 3600)
    minute, second = divmod(minute, 60)
    centsecond = round(second*100.0)
    return '%d:%02d:%02d.%02d' % (int(hour), int(minute), int(second), centsecond)


def WriteASSHead(f, width, height, fontface, fontsize, alpha):
    f.write(
'''\ufeff
[Script Info]
ScriptType: v4.00+
Collisions: Normal
PlayResX: %(width)s
PlayResY: %(height)s

[V4+ Styles]
Format: Name, Fontname, Fontsize, PrimaryColour, SecondaryColour, OutlineColour, BackColour, Bold, Italic, Underline, StrikeOut, ScaleX, ScaleY, Spacing, Angle, BorderStyle, Outline, Shadow, Alignment, MarginL, MarginR, MarginV, Encoding
Style: Default, %(fontface)s, %(fontsize)s, &H%(alpha)02XFFFFFF, &H%(alpha)02XFFFFFF, &H%(alpha)02X000000, &H%(alpha)02X000000, 0, 0, 0, 0, 100, 100, 0.00, 0.00, 1, 1, 0, 7, 20, 20, 20, 0

[Events]
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
''' % {'width': width, 'height': height, 'fontface': fontface, 'fontsize': round(fontsize), 'alpha': 255-round(alpha*255)}
    )


def NeedWhiteBorder(rgb):
    h, l, s = colorsys.rgb_to_hls(((rgb>>16)&0xff)/255, ((rgb>>8)&0xff)/255, (rgb&0xff)/255)
    return (1/12 < h < 7/12 and l < 1/3) or l < 5/12


def CalculateLength(s):
    return max(map(len, s.split('\n')))


def ConvertType2(row, height, bottomReserved):
    return height-bottomReserved-row


if __name__ == '__main__':
    parser = argparse.ArgumentParser()
    parser.add_argument('-o', '--output', metavar='OUTPUT', help=_('Output file'))
    parser.add_argument('-s', '--size', metavar='WIDTHxHEIGHT', required=True, help=_('Stage size in pixels'))
    parser.add_argument('-fn', '--font', metavar='FONT', help=_('Specify font face'), default=_('(FONT) sans-serif')[7:])
    parser.add_argument('-fs', '--fontsize', metavar='SIZE', help=(_('Default font size')), type=float, default=25.0)
    parser.add_argument('-a', '--alpha', metavar='ALPHA', help=_('Text opaque'), type=float, default=1.0)
    parser.add_argument('-l', '--lifetime', metavar='SECONDS', help=_('Duration of comment display'), type=float, default=5.0)
    parser.add_argument('-p', '--protect', metavar='HEIGHT', help=_('Reserve blank on the bottom of the stage'), type=int, default=0)
    parser.add_argument('-r', '--reduce', action='store_true', help=_('Reduce the amount of comments if stage is full'))
    parser.add_argument('file', metavar='FILE', nargs='+', help=_('Comment file to be processed'))
    args = parser.parse_args()
    try:
        width, height = str(args.size).split('x', 1)
        width = int(width)
        height = int(height)
    except ValueError:
        raise ValueError(_('Invalid stage size: %r') % args.size)
    comments = []
    for i in args.file:
        with open(i, 'r', encoding='utf-8') as f:
            CommentProcesser = {None: None, 'Niconico': ReadCommentsNiconico, 'Acfun': ReadCommentsAcfun, 'Bilibili': ReadCommentsBilibili}[ProbeCommentFormat(f)]
            if not CommentProcesser:
                raise ValueError(_('Unknown comment file format: %s') % i)
            for comment in CommentProcesser(f, args.fontsize):
                comments.append(comment)
    if args.output:
        fo = open(args.output, 'w', encoding='utf-8', newline='\r\n')
    else:
        fo = sys.stdout
    comments.sort()
    ProcessComments(comments, fo, width, height, args.protect, args.font, args.fontsize, args.alpha, args.lifetime, args.reduce)
    if args.output:
        fo.close()