import mimetypes
from importlib.resources import files
from urllib.parse import unquote

from html5tagger import E
from sanic import Blueprint, Sanic, raw
from sanic.exceptions import Forbidden, NotFound

from cista import auth, config, session, watching
from cista.api import bp
from cista.util import filename
from cista.util.apphelpers import handle_sanic_exception

app = Sanic("cista", strict_slashes=True)
app.blueprint(auth.bp)
app.blueprint(bp)
app.exception(Exception)(handle_sanic_exception)

@app.before_server_start
async def main_start(app, loop):
    config.load_config()
    await watching.start(app, loop)

@app.after_server_stop
async def main_stop(app, loop):
    await watching.stop(app, loop)

@app.on_request
async def use_session(req):
    req.ctx.session = session.get(req)
    try:
        req.ctx.user = config.config.users[req.ctx.session["username"]]  # type: ignore
    except (AttributeError, KeyError, TypeError):
        req.ctx.user = None
    # CSRF protection
    if req.method == "GET" and req.headers.upgrade != "websocket":
        return  # Ordinary GET requests are fine
    # Check that origin matches host, for browsers which should all send Origin.
    # Curl doesn't send any Origin header, so we allow it anyway.
    origin = req.headers.origin
    if origin and origin.split("//", 1)[1] != req.host:
        raise Forbidden("Invalid origin: Cross-Site requests not permitted")

@app.before_server_start
def http_fileserver(app, _):
    bp = Blueprint("fileserver")
    bp.on_request(auth.verify)
    bp.static("/files/", config.config.path, use_content_range=True, stream_large_files=True, directory_view=True)
    app.blueprint(bp)

@app.get("/<path:path>", static=True)
async def wwwroot(req, path=""):
    """Frontend files only"""
    name = filename.sanitize(unquote(path)) if path else "index.html"
    try:
        index = files("cista").joinpath("wwwroot", name).read_bytes()
    except OSError as e:
        raise NotFound(f"File not found: /{path}", extra={"name": name, "exception": repr(e)})
    mime = mimetypes.guess_type(name)[0] or "application/octet-stream"
    return raw(index, content_type=mime)