# Copyright (c) 2018 Yubico AB
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#   without modification, are permitted provided that the following
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"""
Example demo server to use a supported web browser to call the WebAuthn APIs
to register and use a credential.

See the file README.adoc in this directory for details.

Navigate to http://localhost:5000 in a supported web browser.
"""

import os

from flask import Flask, abort, jsonify, redirect, request, session

from fido2.server import Fido2Server
from fido2.webauthn import PublicKeyCredentialRpEntity, PublicKeyCredentialUserEntity

app = Flask(__name__, static_url_path="")
app.secret_key = os.urandom(32)  # Used for session.

rp = PublicKeyCredentialRpEntity(name="Demo server", id="localhost")
server = Fido2Server(rp)


# Registered credentials are stored globally, in memory only. Single user
# support, state is lost when the server terminates.
credentials = []


@app.route("/")
def index():
    return redirect("/index.html")


@app.route("/api/register/begin", methods=["POST"])
def register_begin():
    options, state = server.register_begin(
        PublicKeyCredentialUserEntity(
            id=b"user_id",
            name="a_user",
            display_name="A. User",
        ),
        credentials,
        user_verification="discouraged",
        authenticator_attachment="cross-platform",
    )

    session["state"] = state
    print("\n\n\n\n")
    print(dict(options))
    print("\n\n\n\n")

    return jsonify(dict(options))


@app.route("/api/register/complete", methods=["POST"])
def register_complete():
    response = request.json
    print("RegistrationResponse:", response)
    auth_data = server.register_complete(session["state"], response)

    credentials.append(auth_data.credential_data)
    print("REGISTERED CREDENTIAL:", auth_data.credential_data)
    return jsonify({"status": "OK"})


@app.route("/api/authenticate/begin", methods=["POST"])
def authenticate_begin():
    if not credentials:
        abort(404)

    options, state = server.authenticate_begin(credentials)
    session["state"] = state

    return jsonify(dict(options))


@app.route("/api/authenticate/complete", methods=["POST"])
def authenticate_complete():
    if not credentials:
        abort(404)

    response = request.json
    print("AuthenticationResponse:", response)
    server.authenticate_complete(
        session.pop("state"),
        credentials,
        response,
    )
    print("ASSERTION OK")
    return jsonify({"status": "OK"})


def main():
    print(__doc__)
    # Note: using localhost without TLS, as some browsers do
    # not allow Webauthn in case of TLS certificate errors.
    # See https://lists.w3.org/Archives/Public/public-webauthn/2022Nov/0135.html
    app.run(host="localhost", debug=False)


if __name__ == "__main__":
    main()