import asyncio
import copy
import os
import zipfile
from pathlib import Path
from typing import Union, List
from urllib.parse import urlparse

import aioboto3
import aiofiles
from nio import (
    RedactedEvent,
    RoomMessageFormatted,
    RoomMessageMedia,
    Event,
    RoomMessagesError,
    AsyncClient,
    MessageDirection
)

"""
Inspired by https://github.com/russelldavies/matrix-archive/blob/master/matrix-archive.py
"""


class RoomEvents:
    def __init__(self, room_id: str):
        self._room_id = room_id
        self._events: List[Event] = []

    def add_event(self, event):
        self._events.append(event)

    def all(self):
        return copy.deepcopy(self._events)

    def jsonify(self):
        dump = [x.source for x in self._events]
        return dump


def is_valid_event(event: Event):
    return isinstance(event, (RoomMessageFormatted, RedactedEvent, RoomMessageMedia))


async def download_mxc(client: AsyncClient, url: str) -> bytes:
    mxc = urlparse(url)
    response = await client.download(mxc.netloc, mxc.path.strip("/"))
    if hasattr(response, "body"):
        return response.body
    else:
        return b''


async def zip_directory(directory_path, zip_path):
    loop = asyncio.get_event_loop()
    await loop.run_in_executor(None, _zip_directory, directory_path, zip_path)


def _zip_directory(directory_path, zip_path):
    with zipfile.ZipFile(zip_path, 'w', zipfile.ZIP_DEFLATED) as zip_file:
        for root, dirs, files in os.walk(directory_path):
            for file in files:
                file_path = str(os.path.join(root, file))
                zip_file.write(file_path, os.path.relpath(file_path, directory_path))


async def upload_to_r2(source_file: Union[str, Path], destination_file: str, bucket_name: str, accountid: str, access_key_id: str, access_key_secret: str):
    session = aioboto3.Session(
        aws_access_key_id=access_key_id,
        aws_secret_access_key=access_key_secret,
    )
    async with session.resource(
            service_name="s3",
            endpoint_url=f'https://{accountid}.r2.cloudflarestorage.com',
    ) as s3:
        bucket = await s3.Bucket(bucket_name)
        async with aiofiles.open(source_file, 'rb') as f:
            return await bucket.upload_fileobj(f, destination_file)


def trim_filename(filename, max_length=255):
    extension = os.path.splitext(filename)[1]
    max_length -= len(extension)
    if len(filename) > max_length:
        filename = filename[:max_length]
    filename += extension

    return filename


async def fetch_events(client: AsyncClient, room_id: str, start_token: str, direction: MessageDirection) -> RoomEvents:
    room_events = RoomEvents(room_id)
    events = []
    while True:
        response = await client.room_messages(
            room_id,
            start=start_token,
            limit=1000,
            direction=direction
        )
        if isinstance(response, RoomMessagesError):
            raise Exception(f'Failed to read room "{room_id}": {response.message}')
        if len(response.chunk) == 0:
            break
        events.extend(event for event in response.chunk)
        start_token = response.end

    if direction == MessageDirection.back:
        events = reversed(events)

    for event in events:
        room_events.add_event(event)

    return room_events