import sys
import aiohttp
from flask import Blueprint
from flask import current_app
from flask import request
from flask.json import jsonify
from werkzeug.exceptions import abort

from capsulflask.db import  my_exec_info_message

bp = Blueprint("spoke", __name__, url_prefix="/spoke")

def authorized_as_hub(id):
  auth_header_value = request.headers.get('Authorization').replace("Bearer ", "")
  return auth_header_value == current_app.config["HUB_TOKEN"]

@bp.route("/heartbeat", methods=("POST"))
def heartbeat():
  if authorized_as_hub(id):
    # make request to hub-domain.com/hub/heartbeat/{current_app.config["SPOKE_HOST_ID"]}
    # succeed or fail based on whether the request succeeds or fails.
    pass
  else:
    current_app.logger.info(f"/hosts/heartbeat returned 401: invalid hub token")
    return abort(401, "invalid hub token")

@bp.route("/operation", methods=("POST"))
def operation():
  if authorized_as_hub(id):
    request_body = request.json()
    handlers = {
      "capacity_avaliable": handle_capacity_avaliable,
      "get": handle_get,
      "list_ids": handle_list_ids,
      "create": handle_create,
      "destroy": handle_destroy,
    }

    error_message = ""
    types_csv = ", ".join(handlers.keys())
    if isinstance(request_body, dict) and 'type' in request_body:
      if request_body['type'] in handlers:
        try:
          return handlers[request_body['type']](request_body)
        except:
          error_message = my_exec_info_message(sys.exc_info())
          current_app.logger.error(f"unhandled exception in {request_body['type']} handler: {error_message}")
          return jsonify(dict(error_message=error_message))
      else:
        error_message = f"'type' must be one of {types_csv}"
    else:
      error_message = "'type' json property is required"

    if error_message != "":
      current_app.logger.info(f"/hosts/operation returned 400: {error_message}")
      return abort(400, f"bad request; {error_message}")
  else:
    current_app.logger.info(f"/hosts/operation returned 401: invalid hub token")
    return abort(401, "invalid hub token")

def handle_capacity_avaliable(request_body):
  if 'additional_ram_bytes' not in request_body:
    current_app.logger.info(f"/hosts/operation returned 400: additional_ram_bytes is required for capacity_avaliable")
    return abort(400, f"bad request; additional_ram_bytes is required for capacity_avaliable")

  has_capacity = current_app.config['SPOKE_MODEL'].capacity_avaliable(request_body['additional_ram_bytes'])
  return jsonify(dict(assignment_status="assigned", capacity_avaliable=has_capacity))

def handle_get(request_body):
  if 'id' not in request_body:
    current_app.logger.info(f"/hosts/operation returned 400: id is required for get")
    return abort(400, f"bad request; id is required for get")

  vm = current_app.config['SPOKE_MODEL'].get(request_body['id'])
  
  return jsonify(dict(assignment_status="assigned", id=vm.id, host=vm.host, ipv4=vm.ipv4, ipv6=vm.ipv6))

def handle_list_ids(request_body):
  return jsonify(dict(assignment_status="assigned", ids=current_app.config['SPOKE_MODEL'].list_ids()))

def handle_create(request_body):
  parameters = ["operation_id", "email", "id", "template_image_file_name", "vcpus", "memory_mb", "ssh_public_keys"]
  error_message = ""
  for parameter in parameters:
    if parameter not in request_body:
      error_message = f"{error_message}\n{parameter} is required for create"
  
  if error_message != "":
    current_app.logger.info(f"/hosts/operation returned 400: {error_message}")
    return abort(400, f"bad request; {error_message}")

  # try to aquire operation_id
  assignment_status = "assigned"

  if assignment_status == "assigned":
    try:
      current_app.config['SPOKE_MODEL'].create(
        email=request_body['email'],
        id=request_body['id'],
        template_image_file_name=request_body['template_image_file_name'],
        vcpus=request_body['vcpus'],
        memory_mb=request_body['memory_mb'],
        ssh_public_keys=request_body['ssh_public_keys'],
      )
    except:
      error_message = my_exec_info_message(sys.exc_info())
      params = f"email='{request_body['email']}', id='{request_body['id']}', "
      params = f"{params}, template_image_file_name='{request_body['template_image_file_name']}', vcpus='{request_body['vcpus']}'"
      params = f"{params}, memory_mb='{request_body['memory_mb']}', ssh_public_keys='{request_body['ssh_public_keys']}'"
      current_app.logger.error(f"current_app.config['SPOKE_MODEL'].create({params}) failed: {error_message}")
      return jsonify(dict(assignment_status=assignment_status, error_message=error_message))

  return jsonify(dict(assignment_status=assignment_status))

def handle_destroy(request_body):
  if 'id' not in request_body:
    current_app.logger.info(f"/hosts/operation returned 400: id is required for destroy")
    return abort(400, f"bad request; id is required for destroy")

  if 'email' not in request_body:
    current_app.logger.info(f"/hosts/operation returned 400: email is required for destroy")
    return abort(400, f"bad request; email is required for destroy")

  try:
    current_app.config['SPOKE_MODEL'].destroy(id=request_body['id'], email=request_body['email'])
  except:
    error_message = my_exec_info_message(sys.exc_info())
    current_app.logger.error(f"current_app.config['SPOKE_MODEL'].destroy(id='{request_body['id']}', email='{request_body['email']}') failed: {error_message}")
    return jsonify(dict(assignment_status="assigned", status="error", error_message=error_message))
  
  return jsonify(dict(assignment_status="assigned", status="success"))