#!/usr/bin/env python3
import csv
import os
import tempfile
from math import ceil
from operator import itemgetter

from fillpdf import fillpdfs
from pdfrw import PdfReader, PdfWriter

# Change to your needs
event_period = "25.05. - 29.05.22"
event_org = "Verein der Freunde und Förderer der Bundesfachschaftentagung Elektrotechnik e.V."
event_name = "90. Bundesfachschaftentagung Elektrotechnik"
attendees_csv = "teilnehmer_innen.csv"
empty_sheets = 1
template_form = "210705_Teilnehmendenliste_abgestimmt.pdf"
date_list = ["25.05.22", "26.05.22", "27.05.22", "28.05.22", "29.05.22"]

# Nothing to change below here

form_mapping = [("6", "20", "21"), ("19", "40", "41"), ("18", "39", "22"),
                ("17", "42", "23"), ("16", "43", "24"), ("15", "44", "25"), ("14", "45", "26"),
                ("13", "46", "27"), ("12", "Text7", "28"), ("11", "29", "34"), ("10", "30", "35"),
                ("9", "31", "36"), ("8", "32", "37"), ("7", "33", "38")]


def read_csv(csv_path):
    persons = []
    try:
        csvfile = open(csv_path, newline='')
    except FileNotFoundError:
        print("[X] File {} not found!".format(csv_path))
        exit(-1)
    else:
        with csvfile:
            reader = csv.DictReader(csvfile, delimiter=",")
            persons = [{"Name": f"{t['Vorname']} {t['Nachname']}", "Hochschule": f"{t['Standort']}"} for t in reader if
                       t['Status'] == "Student"]
            persons.sort(key=itemgetter("Hochschule", "Name"))

    return persons


def fill_pdf_form(working_directory, form, persons, zeitraum, form_date, org_name, name, add_sheets):
    page = 1
    output_file_name = "output"
    personen_pro_seite = 14

    anzahl_seiten = ceil(len(persons) / personen_pro_seite)
    pdfs = []

    for j in range(anzahl_seiten + add_sheets):
        felder = {}
        i = 0
        for item in form_mapping:
            if personen_pro_seite * j + i < len(persons):
                felder[item[0]] = str(j * personen_pro_seite + i + 1)
                felder[item[1]] = persons[j * personen_pro_seite + i]["Name"]
                felder[item[2]] = persons[j * personen_pro_seite + i]["Hochschule"]
            i += 1

            if i == personen_pro_seite:
                output_file_path = os.path.join(working_directory, f'{output_file_name}{page}.pdf')

                headers = {"1": page, "2": zeitraum, "3": form_date, "4": org_name, "5": name}

                fields = {**headers, **felder}

                fillpdfs.write_fillable_pdf(input_pdf_path=form, output_pdf_path=output_file_path, data_dict=fields,
                                            flatten=True)
                pdfs.append(output_file_path)
                page += 1

    return pdfs


def concat_pdfs(file_list: list, output_pdf: str):
    writer = PdfWriter()
    for input_file in file_list:
        reader = PdfReader(input_file)
        writer.addpages(reader.pages)
        writer.trailer.Info = reader.Info

    writer.write(output_pdf)


if __name__ == "__main__":
    workdir = tempfile.mkdtemp()
    cwd = os.getcwd()
    csv_file_path = os.path.join(cwd, attendees_csv)
    person_list = read_csv(csv_file_path)
    form_path = os.path.join(cwd, template_form)

    # check if form exits
    if not os.path.exists(form_path):
        print("[X] File {} not found!".format(form_path))
        exit(1)

    for date in date_list:
        final_pdf_name = f'teilnehmendenliste_{date.replace(". ", "_")}.pdf'
        print(f'Creating {final_pdf_name}... ', end='')
        final_pdf_path = os.path.join(cwd, final_pdf_name)
        output_files = fill_pdf_form(workdir, form_path, person_list, event_period, date, event_org, event_name,
                                     empty_sheets)
        concat_pdfs(file_list=output_files, output_pdf=final_pdf_path)
        print('done!')