import sys
import os
import time
import datetime
import collections
import subprocess
import shutil

import base64
import json
import uuid
import pickle

import numpy as np

import joblib

from .Utils import get_random_string, AtomicCounter

from .log import LOGGER

SESSION_BASE_PATH = './data/session'
SESSION_FOLDER = SESSION_BASE_PATH + "/" + datetime.datetime.now().strftime('%Y-%m-%d')


def manage_session_folders():
    if not os.path.exists(SESSION_BASE_PATH):
        os.makedirs(SESSION_BASE_PATH)
    if not os.path.exists(SESSION_FOLDER):
        shutil.rmtree(SESSION_BASE_PATH)
        os.makedirs(SESSION_FOLDER)


class Session():

    def __init__(self, session_id, model):
        LOGGER.info("Instantiating a new session object with id: %s" % (session_id))

        self.storage_type = "file" # this will be "table" or "file"
        self.storage_path = "data/" # this will be a file path
        self.table_service = None # this will be an instance of TableService

        self.model = model
        self.current_transform = ()

        self.current_snapshot_string = get_random_string(8)
        self.current_snapshot_idx = 0
        self.current_request_counter = AtomicCounter()
        self.request_list = []

        self.session_id = session_id
        self.creation_time = time.time()
        self.last_interaction_time = self.creation_time

    def reset(self, soft=False, from_cached=None):
        if not soft:
            self.model.reset() # can't fail, so don't worry about it
        self.current_snapshot_string = get_random_string(8)
        self.current_snapshot_idx = 0
        self.current_request_counter = AtomicCounter()
        self.request_list = []

        if self.storage_type == "table":
            self.table_service.insert_entity("webtoolsessions",
            {
                "PartitionKey": str(np.random.randint(0,8)),
                "RowKey": str(uuid.uuid4()),
                "session_id": self.current_snapshot_string,
                "server_hostname": os.uname()[1],
                "server_sys_argv": ' '.join(sys.argv),
                "base_model": from_cached
            })

    def load(self, encoded_model_fn):
        model_fn = base64.b64decode(encoded_model_fn).decode('utf-8')

        print(model_fn)

        del self.model
        self.model = joblib.load(model_fn)

    def save(self, model_name):

        if self.storage_type is not None:
            assert self.storage_path is not None # we check for this when starting the program

            snapshot_id = "%s_%d" % (model_name, self.current_snapshot_idx)
            
            print("Saving state for %s" % (snapshot_id))
            base_dir = os.path.join(self.storage_path, self.current_snapshot_string)
            if not os.path.exists(base_dir):
                os.makedirs(base_dir, exist_ok=False)
            
            model_fn = os.path.join(base_dir, "%s_model.p" % (snapshot_id))
            #joblib.dump(self.model, model_fn, protocol=pickle.HIGHEST_PROTOCOL)

            if self.storage_type == "file":
                request_list_fn = os.path.join(base_dir, "%s_request_list.p" % (snapshot_id))
                joblib.dump(self.request_list, request_list_fn, protocol=pickle.HIGHEST_PROTOCOL)
            elif self.storage_type == "table":
                # We don't serialize the request list when saving to table storage
                pass

            self.current_snapshot_idx += 1
            return base64.b64encode(model_fn.encode('utf-8')).decode('utf-8') # this is super dumb
        else:
            return None
    
    def add_entry(self, data):
        data = data.copy()
        data["time"] = datetime.datetime.now()
        data["current_snapshot_index"] = self.current_snapshot_idx
        current_request_counter = self.current_request_counter.increment()
        data["current_request_index"] = current_request_counter

        assert "experiment" in data

        if self.storage_type == "file":
            self.request_list.append(data)
        
        elif self.storage_type == "table":

            data["PartitionKey"] = self.current_snapshot_string
            data["RowKey"] = "%s_%d" % (data["experiment"], current_request_counter)

            for k in data.keys():
                if isinstance(data[k], dict) or isinstance(data[k], list):
                    data[k] = json.dumps(data[k])
            
            try:
                self.table_service.insert_entity("webtoolinteractions", data)
            except Exception as e:
                print(e)
        else:
            # The storage_type / --storage_path command line args were not set
            pass