# -*- coding:utf-8 -*-
from chat_downloader import ChatDownloader
import sys
import math
import urllib.request
import re

# 目前仅支持开启了chat的回放，看不懂chat-downloader的源代码，甚至不想把直播安排进todo

def sec2hms(sec):# 时间转换
    hms = str(int(sec//3600)).zfill(2)+':' + \
        str(int((sec % 3600)//60)).zfill(2)+':'+str(round(sec % 60, 2))
    return hms


url = 'youtu.be/'+sys.argv[1]
html = urllib.request.urlopen("https://www.youtube.com/watch?v="+sys.argv[1]).read().decode('utf-8')
name = [] #预留加人用
title = re.findall("<title>(.+?)</title>",html)[0].replace(' - YouTube','')
name += re.findall('itemprop="name" content="(.+?)">',html)
chat = ChatDownloader().get_chat(url,message_groups=['messages','superchat']) #默认普通评论和sc

count = 0
limitLineAmount = 12  # 屏上弹幕行数限制
danmakuPassageway = []  # 塞弹幕用，记录每行上一条弹幕的消失时间
for i in range(limitLineAmount):
    danmakuPassageway.append(0)
fontName = 'Source Han Sans JP'  # 字体自己换
videoWidth = 1280  # 视频宽度，按720P处理了后面的内容，不建议改
videoHeight = 720  # 视频高度
OfficeBgHeight = 72
OfficeSize = 36
fontSize = 58
head = '[Script Info]\n\
; Script generated by Aegisub 3.2.2\n\
; http://www.aegisub.org/\n\
ScriptType: v4.00+\n\
PlayResX: 1280\n\
PlayResY: 720\n\
\n\
[V4+ Styles]\n\
Format: Name, Fontname, Fontsize, PrimaryColour, SecondaryColour, OutlineColour, BackColour, Bold, Italic, Underline, StrikeOut, ScaleX, ScaleY, Spacing, Angle, BorderStyle, Outline, Shadow, Alignment, marginL, marginR, marginV, Encoding\n\
Style: Default,微软雅黑,54,&H00FFFFFF,&H00FFFFFF,&H00000000,&H00000000,0,0,0,0,100,100,0,0,1,2,0,2,0,0,0,0\n\
Style: Alternate,微软雅黑,36,&H00FFFFFF,&H00FFFFFF,&H00000000,&H00000000,0,0,0,0,100,100,0,0,1,2,0,2,0,0,0,0\n\
Style: Office,'+fontName+','+str(OfficeSize)+',&H00FFFFFF,&H00FFFFFF,&H00000000,&H00000000,-1,0,0,0,100,100,2,0,1,1.5,0,2,0,0,10,0\n\
Style: Danmaku,'+fontName+','+str(fontSize)+',&H00FFFFFF,&H00FFFFFF,&H00000000,&H00000000,-1,0,0,0,100,100,2,0,1,1.5,0,2,0,0,10,0\n\n\
[Events]\n\
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text\n'

f = open(sys.argv[1]+'.ass','w',encoding='utf-8-sig')
f.write(head)
for message in chat:
    if message['time_in_seconds'] > 0:
        vpos = message['time_in_seconds']
        vpos_end = vpos+8 # 普通弹幕的时长，默认8秒
    else:
        continue
    if 'name' not in message['author'].keys():
        continue
    if 'money' in message.keys():
        text = '('+str(message['money']['amount'])+message['money']['currency']+')' # 打钱的标上数额
        if 'message' in message.keys():
            if message['message']:
                text += message['message'] # 打钱有留言的加上
        vpos_end += 2 # 打钱的多给2秒
    else:
        text=message['author']['name']+'： '+message['message'] if message['author']['name'] in name else message['message'] # 没打钱的直接记录弹幕，设置了的号加上账号名字
    if 'emotes' in message.keys():
        for i in message['emotes']:
            if i['is_custom_emoji']:
                text = text.replace(i['name'],'')
            else:
                text = text.replace(i['name'],i['id'])
    if text:
        if len(text) == 0:
            continue
    else:
        continue
    if message['author']['name'] in name: # 特定账号的弹幕放上面并加上背景
        f.write('Dialogue: 4,'+sec2hms(vpos)+','+sec2hms(vpos_end)+',Office,,0,0,0,,{\\an5\\p1\\pos('+str(videoWidth/2)+','+str(math.floor(OfficeBgHeight/2))+')\\bord0\\1c&H000000&\\1a&H78&}'+'m 0 0 l '+str(videoWidth)+' 0 l '+str(videoWidth) + ' '+str(OfficeBgHeight)+' l 0 '+str(OfficeBgHeight)+'\n')
        f.write('Dialogue: 5,'+sec2hms(vpos)+','+sec2hms(vpos_end)+',Office,,0,0,0,,{\\an5\\pos('+str(videoWidth/2)+','+str(math.floor(OfficeBgHeight/2))+')\\bord0\\fsp0}'+text+'\n')
        count += 1
    else: # 其他人的弹幕放滚动
        vpos_next_min = float('inf')
        vpos_next = vpos+1280/(len(text)*60+1280) * 8
        for i in range(limitLineAmount):
                if vpos_next >= danmakuPassageway[i]:
                    passageway_index = i
                    danmakuPassageway[i] = vpos+8
                    break
                elif danmakuPassageway[i] < vpos_next_min:
                    vpos_next_min = danmakuPassageway[i]
                    Passageway_min = i
                if i == limitLineAmount-1 and vpos_next < vpos_next_min:
                    passageway_index = Passageway_min
                    danmakuPassageway[Passageway_min] = vpos+8
        # 计算弹幕位置
        sx = videoWidth
        sy = fontSize*(passageway_index)
        ex = 0
        for i in text:
            if re.search("[A-Za-z 0-9',.]",i):
                ex = ex-30
            else:
                ex = ex-60
        ey = fontSize*(passageway_index)
        f.write('Dialogue: 0,'+sec2hms(vpos)+','+ sec2hms(vpos_end) + ',Danmaku,'+message['author']['name'].replace(',','')+',0,0,0,,{\\an7\\move('+str(sx)+','+str(sy)+','+str(ex)+','+str(ey)+')}'+text+'\n')
        count += 1

f.close()
print(title+'的弹幕已经存为'+sys.argv[1]+'.ass,共'+str(count)+'条')