import dataclasses
from dataclasses import field
from typing import Optional, Any
from enum import IntEnum, IntFlag
from json import JSONEncoder

class PostType(IntEnum):
    UNKNOWN = 0
    POST = 1
    REPOST = 2
    PREVIEW = 3
    TOMBSTONE = 4

class DateType(IntEnum):
    UNKNOWN = 0
    CREATED = 1
    EDITED = 2
    RETRIEVED = 3

class DateMeta(IntFlag):
    NONE = 0
    ESTIMATE = 1
    GUESS = 1 << 1
    LOOSE_PRECISION = 1 << 2
    EDITED_AT_UNKNOWN_TIME = 1 << 3
    ASSUMED_TYPE = 1 << 4

class MediaType(IntEnum):
    UNKNOWN = 0
    FILE = 1
    AUDIO = 2
    IMAGE = 3
    VIDEO = 4
    VIDEO_SPLIT = 5
    ANIMATION = 6

class TagType(IntEnum):
    UNKNOWN = 0
    GENERAL = 1
    ARTIST = 2
    CHARACTER = 3
    COPYRIGHT = 4
    META = 5
    DEPRECATED = 6

def df(c: Any) -> Any:
    return field(default_factory=lambda: c)

def default_url_ext_guess(url: str) -> str:
    slash = url.find('/')
    if slash < 0:
        return ''
    url = url[slash:]
    question = url.rfind('?')
    if question >= 0:
        url = url[0:question]
    s = url.split('.')
    if len(s) > 1:
        return s[-1]
    return ''

@dataclasses.dataclass
class Url():
    url: str
    ext: str
    def __init__(self, url: str, ext: Optional[str] = None) -> None:
        self.url = url
        if not ext:
            ext = default_url_ext_guess(url)
        self.ext = ext

@dataclasses.dataclass
class Media():
    type: MediaType = MediaType.UNKNOWN
    url: Url = df(Url(''))
    thumbnail_url: Url = df(Url(''))

@dataclasses.dataclass
class File(Media):
    type: MediaType = MediaType.FILE
    name: str = ''

@dataclasses.dataclass
class Audio(Media):
    type: MediaType = MediaType.AUDIO

@dataclasses.dataclass
class Image(Media):
    type: MediaType = MediaType.IMAGE

@dataclasses.dataclass
class Video(Media):
    type: MediaType = MediaType.VIDEO

@dataclasses.dataclass
class VideoSplit(Media):
    type: MediaType = MediaType.VIDEO_SPLIT
    audio_url: Url = df(Url(''))
    subtitle_url: Url = df(Url(''))

@dataclasses.dataclass
class Animation(Media):
    type: MediaType = MediaType.ANIMATION
    frames: list[tuple[str, int]] = df([])

@dataclasses.dataclass
class Tag():
    type: TagType = TagType.UNKNOWN
    name: str = ''
    alts: dict[str, str] = df({})

'''
Date(DateType.CREATED, (1396411200.0, 1396756800.0), DateMeta.ESTIMATE)
 - Post is estimated to have been created at some point between April 2nd and 6th 2014.

Date(DateType.EDITED, (1396411200.0, 1550247862.0), DateMeta.EDITED_AT_UNKNOWN_TIME)
 - We have no clue when the post was edited, but it had to have been between the time it was created and now.
 - EDITED_AT_UNKNOWN_TIME should be used when either of CREATED and/or RETRIEVED are used as placeholders.
   It can be combined with GUESS or ESTIMATE if, for example, there is some indication about the end of the range.

Date(DateType.RETRIEVED, (1550247862.0, 1550247862.0), DateMeta.NONE)
 - Time of processing this post. Will likely be slightly after it was actually retrived but that is negligible.
 - RETRIEVED can still have a range and meta if applicable.

Date(DateType.CREATED, (1483228800.0, 1546300800.0), DateMeta.LOOSE_PRECISION)
 - Date is exactly between "01 Jan 2017 12:00:00 AM UTC" and "01 Jan 2019 12:00:00 AM UTC".
   Combined with LOOSE_PRECISION, the application will assume a meaning of "between 2017 and 2019".

Date(DateType.CREATED, (1145059200.0, 1145059200.0), DateMeta.ASSUMED_TYPE)
 - The date of April 15th 2006 is associated with the resource. We are assuming that's the creation date.
'''
@dataclasses.dataclass
class Date():
    type: DateType = DateType.UNKNOWN
    range: tuple[float, float] = (0.0, 0.0)
    meta: DateMeta = DateMeta.NONE
    note: str = ''

@dataclasses.dataclass
class User():
    unique_id: str = ''
    username: str = ''
    display_name: str = ''
    profile_picture_url: Url = df(Url(''))

@dataclasses.dataclass
class PostRef():
    unique_id: str = ''

'''
V4:
 - Improved date.
 - Track origin module.
 - Ends when all current modules are ported and/or completed.
V5:
 - Formatted body/text.
'''
@dataclasses.dataclass
class Post():
    version: int = 4
    module: str = ''
    type: PostType = PostType.UNKNOWN
    unique_id: str = ''
    raw_responses: dict[str, str] = df({})
    url: str = ''
    dates: list[Date] = df([])
    author: User = df(User())
    title: str = ''
    text: str = ''
    likes: Optional[int] = None
    bookmarks: Optional[int] = None
    reposts: Optional[int] = None
    quotes: Optional[int] = None
    comments: Optional[int] = None
    views: Optional[int] = None
    tags: list[Tag] = df([])
    links: list[str] = df([])
    media: dict[str, Media] = df({})
    post: PostRef = df(PostRef())
    quoted: PostRef = df(PostRef())
    in_reply_to: PostRef = df(PostRef())

class PostEncoder(JSONEncoder):
    def default(self, o: Any) -> Any:
        return o.__dict__