from nio import *

import asyncio
import yaml


async def send_png(room: MatrixRoom, filename: str) -> None:
    import imagesize
    import os
    basename = os.path.basename(filename)
    w, h = imagesize.get(filename)

    file = open(filename, "r+b")
    size = os.path.getsize(filename)

    filename = os.path.basename(filename)
    resp, keys = await client.upload(file, content_type="image/png", filename=basename)

    if not isinstance(resp, UploadResponse):
        raise OSError("Couldn't upload file.")

    content = {
        "body": basename,
        "info": {
            "size": size,
            "mimetype": "image/png",
            "w": w, "h": h
        },
        "msgtype": "m.image",
        "url": resp.content_uri,
    }
    file.close()

    await client.room_send(room.room_id, message_type="m.room.message", content=content)


# Our message callback. It should be passed through a router.
async def msg_cb(room: MatrixRoom, event: RoomMessageText) -> None:
    import re
    import latex
    if event.sender == client.user_id:
        return

    for tex in re.findall(r'((?:\$[^\$]+\$)|(?:\$\$[^\$]+\$\$)|(?:\\\[[^\]]+\\\]))', event.body, re.M):
        print("Text:", tex)
        try:
            filename = latex.render("", tex)
            await send_png(room, filename)
        except FileNotFoundError as e:
            content = {
                "msgtype": "m.text",
                "body": f"Couldn't parse LaTeX correctly.\n```{e.args[0]}\n```",
                "formatted_body": f"Couldn't parse LaTeX correctly.<br><code><pre>{e.args[0]}</pre></code>",
            }
            await client.room_send(room.room_id, message_type="m.room.message", content=content)
        except OSError:
            content = {
                "msgtype": "m.text",
                "body": "???",
                "formatted_body": "???"
            }

            await client.room_send(room.room_id, message_type="m.room.message", content=content)

# Our file callback.
async def file_cb(room: MatrixRoom, event: RoomMessageFile) -> None:
    url = event.url
    filename = event.body


async def main() -> None:
    # Load our config file.
    global client

    config = {}
    try:
        with open('texlily.yaml', 'r') as conf:
            config = yaml.safe_load(conf)
        # Retrieve our configuration
        homeserver = str(config["homeserver"])
        user = str(config["user"])
        token = str(config["token"])
        # path = str(config["path"]) # not used
        # if config file does not exist, quit
    except FileNotFoundError:
        print("No config file found.")
        print("Please create a file named `texlily.yaml` and read the README file.")
        quit()
    except TypeError:
        print("Invalid configuration file.")
        quit()

    client = AsyncClient(homeserver)
    client.access_token = token
    client.user_id = user

    # Bad kludge!
    await client.sync(timeout=3000)

    # Register all of the callbacks
    client.add_event_callback(msg_cb, RoomMessageText)
    client.add_event_callback(file_cb, RoomMessageFile)

    await client.sync_forever(timeout=10000, full_state=True)

asyncio.run(main())