from openflexure_microscope.api.utilities import JsonPayload
from openflexure_microscope.api.v1.views import MicroscopeViewPlugin
from openflexure_microscope.exceptions import TaskDeniedException

from flask import request, Response, escape, jsonify, abort


class IdentifyAPI(MicroscopeViewPlugin):
    """
    A simple example API plugin, attached through the main microscope plugin.
    """
    def get(self):
        """
        Method to call when an HTTP GET request is made.
        """
        data = self.plugin.identify()  # Call a method from our plugin, using the MicroscopeViewPlugin.plugin shortcut
        return Response(escape(data))


class HelloWorldAPI(MicroscopeViewPlugin):
    """
    A method to create, set, and return a new microscope parameter.
    """

    def get(self):
        """
        Method to call when an HTTP GET request is made.
        """

        # If the microscope does not already contain our plugin_string attribute
        if not hasattr(self.microscope, 'plugin_string'):
            # Make a string, using the MicroscopeViewPlugin.plugin shortcut
            self.microscope.plugin_string = self.plugin.hello_world()

        return Response(self.microscope.plugin_string)

    def post(self):
        """
        Method to call when an HTTP POST request is made. 
        Assumes request will include a JSON payload.
        """
        # Get payload JSON
        payload = JsonPayload(request)

        # Extract a value from the JSON key 'plugin_string', and convert to a string. If no value is given, default to empty.
        new_plugin_string = payload.param('plugin_string', default='', convert=str)

        if new_plugin_string:  # If not None or empty
            # Set microscope attribute to the specified string
            self.microscope.plugin_string = new_plugin_string

        return Response(self.microscope.plugin_string)


class LongRunningAPI(MicroscopeViewPlugin):
    """
    An example API plugin that uses a long-running plugin method.
    """
    def post(self):
        """
        Method to call when an HTTP POST request is made.
        """
        # Get payload JSON
        payload = JsonPayload(request)

        # Extract a values from the JSON payload.
        time_to_run = payload.param('time', default=10, convert=int)

        # Attach the long-running method as a microscope task
        try:
            task = self.microscope.task.start(self.plugin.long_running, time_to_run)
            return jsonify(task.state), 202

        except TaskDeniedException:
            return abort(409)


class SomeExceptionAPI(MicroscopeViewPlugin):
    """
    An example API plugin that uses a long-running but broken plugin method.
    """
    def post(self):
        """
        Method to call when an HTTP POST request is made.
        """
        # Get payload JSON
        payload = JsonPayload(request)

        # Attach the long-running method as a microscope task
        try:
            task = self.microscope.task.start(self.plugin.some_exception)
            return jsonify(task.state), 202

        except TaskDeniedException:
            return abort(409)