# This file contains functions related to logging data from the program to a CSV file
# They are mainly but not only called by the ConfigureLogging class in User_Interface.py

import pandas as pd
import globals as g
from datetime import datetime
import os
from tkinter import filedialog
from tkinter import messagebox
import User_Interface as ui

log_data = pd.DataFrame()  # pandas data frame containing logged data
unsaved_data = False  # Bool to indicate if there is unsaved data, set to True each time a datapoint is logged
zero_time = datetime.now()

# create dictionary with all value handles that could be logged
# Key: String that is displayed in UI and column headers. Also serves as handle to access dictionary elements.
# Keys are the same as the rows in the status display ToDo (optional): use this for the status display
# Content: name of the corresponding attribute in the Axis class (in cage_func.py).
# Important: attribute handle must match definition in Axis class exactly, used with axis.getattr() to get values.
axis_data_dict = {
    'PSU Status': 'connected',
    'Voltage Setpoint': 'voltage_setpoint',
    'Actual Voltage': 'voltage',
    'Current Setpoint': 'current_setpoint',
    'Actual Current': 'current',
    'Target Field': 'target_field_comp',
    'Trgt. Field Raw': 'target_field_comp',
    'Target Current': 'target_current',
    'Inverted': 'polarity_switched'
}


def triple_list(key_list):  # creates list with each entry of key_list tripled with axis names before it
    new_list = []  # initialize list
    for key in key_list:  # go through the given list
        for axis_name in ['X', 'Y', 'Z']:  # per given list entry create three, one for each axis
            new_list.append(' '.join((axis_name, key)))  # put axis_name before the given entry and append to new list
    return new_list


def log_datapoint(key_list):  # ToDo: comments
    global log_data
    global unsaved_data
    date = datetime.now().date()
    time = datetime.now().strftime("%H:%M:%S,%f")
    t = (datetime.now() - zero_time).total_seconds()
    data = [[date, time, t]]
    for key in key_list:
        for axis in g.AXES:
            data[0].append(getattr(axis, axis_data_dict[key]))  # get value
    column_names = ["Date", "Time", "t (s)", *triple_list(key_list)]
    new_row = pd.DataFrame(data, columns=column_names)
    log_data = log_data.append(new_row, ignore_index=True)
    unsaved_data = True


def select_file():  # select a file to write logs to
    directory = os.path.abspath(os.getcwd())  # get project directory
    # open file selection dialogue and save path of selected file
    filepath = filedialog.asksaveasfilename(initialdir=directory, title="Set log file",
                                            filetypes=([("Comma Separated Values", "*.csv*")]),
                                            defaultextension=[("Comma Separated Values", "*.csv*")])

    if filepath == '':  # this happens when file selection window is closed without selecting a file
        ui.ui_print("No file selected, can not save logged data.")
        return None
    else:  # a valid file name was entered
        return filepath


def write_to_file(dataframe, filepath):
    # get global variables for use in this function:
    global unsaved_data
    if filepath is not None:  # user has selected a file and no errors occurred
        ui.ui_print("Writing logged data to file", filepath)
        try:
            # write data collected in log_data DataFrame to csv file in german excel format:
            dataframe.to_csv(filepath, index=False, sep=';', decimal=',')
        except PermissionError:
            message = "No permission to write to: \n%s. \nFile may be open in another program." % filepath
            messagebox.showerror("Permission Error", message)
        except BaseException as e:
            message = "Error while trying to write to file \n%s.\n%s" % (filepath, e)
            messagebox.showerror("Error!", message)
        else:  # no exceptions occurred
            unsaved_data = False  # tell everything that there is no unsaved data remaining
            ui.ui_print("Log data saved to", filepath)


def clear_logged_data():  # clears all logged data from data frame
    global log_data  # get global variable
    log_data = pd.DataFrame()  # reset to an empty data frame, i.e. clear all logged data