import os
from pathlib import Path

folders = ["reports_to_convert/", "converted_reports/", "report_archive/"]
for folder in folders:
    if not os.path.exists(folder):
        print('A required directory is missing.')
        try:
            print('Creating directory...')
            os.mkdir(folder)
        except OSError:
            print("Creation of the directory %s failed" % folder)
        else:
            print("Successfully created the directory %s " % folder)

input_folder = Path("reports_to_convert/")
output_folder = Path("converted_reports/")
archive_folder = Path("report_archive/")

# count number of commas in a string
def count_commas(string):
    count = 0
    for character in string:
        if character == ',':
            count += 1
    return count

# returns the value of column x for a row string
def column(x, string):
    column_list = string.split(",")
    #print(column_list)
    return column_list[x-1]

# delete the xth comma in a string
def delete_comma(x, string):
    comma_num = 0
    i = 0
    for character in string:
        if character == ',':
            comma_num += 1
        if comma_num == x:
            new_string = string[:i] + string[i+1:]
            return new_string
        i += 1
    return None

# adds a comma to strings that do not end in a comma
def add_ending_comma(string):
    if string.rstrip()[-1] != ',':
        string = string.rstrip() + ',' + "\n"
    return string

# removes trailing commas from a string
def rmv_tr_commas(raw_line):
    #print('Removing trailing commas...')
    try:
        line = raw_line.rstrip()
        i = len(line) - 1
        while line[i - 1] == ',':
            i -= 1
        return line[:i+1]
    except:
        print('Failed to remove trailing commas.')


# takes file rows as list and removes any elements containing the word "Invoice" and the following 5 elements
def invoice_remove(lst):
    #print('Removing Invoice rows...')
    try:
        for i in range(len(lst)-1, -1, -1):
            if 'Invoice' in lst[i]:
                for j in range(6):
                    lst.pop(i+j)
                    i -= 1
        return lst
    except:
        print('Failed to remove Invoice rows.')

# for each line starting with BSCA, combine the next two lines into BSCA line and remove lines with extra commas
def concat_lines(lst):
    #print('Concatenating lines...')
    try:
        for i in range(len(lst)-1, -1, -1):
            if 'BS' in lst[i]:
                lst[i] = add_ending_comma(lst[i])
                for j in range(2):
                    lst[i] = rmv_tr_commas(lst[i])
                    lst[i] += lst[i+1]
                    lst.pop(i+1)
##                try:
##                    if count_commas(lst[i]) > 34:
##                        lst[i] = delete_comma(10, lst[i])
##                        after_reductions = float(column(10, lst[i])) - float(column(20, lst[i]))
##                        if after_reductions >= 1000:
##                            lst[i] = delete_comma(21, lst[i])
##                except ValueError:
##                    print("BAD")
        return(lst)
    except:
        print('Failed to concatenate lines.')

# write each element of lst to a line in a new csv file
def write_lines(lst, file):
    #print('Writing to file...')
    try:
        with open(output_folder / file, "w") as f:
            for line in lst:
                f.write(line)
        print(file + ' has been created.')
    except:
        print(file + ' COULD NOT BE CREATED.')

if __name__ == "__main__":
    converted = False
    if os.listdir(input_folder) == []:
        print('There are no reports to convert. Place reports in the reports_to_convert folder.')
    else:
        try:
##        print('Scanning reports_to_convert...')
            for file in os.listdir(input_folder):
                if file.endswith(".csv"):
                    #print(file + ' found.')
                    with open(input_folder / file, 'r') as f:
                        #print(file + ' opened. Converting...')
                        lst = f.readlines()
                        write_lines(concat_lines(invoice_remove(lst)), file[:-4]+' - CONVERTED.csv')
                    os.replace(input_folder / file, archive_folder / file)
                    converted = True
            if converted:
                print('-ALL REPORTS SUCESSFULLY CONVERTED-.')
            else:
                print('No valid .csv files found in reports_to_convert.')
        except:
            print('*THERE WAS A PROBLEM CONVERTING THE REPORTS*')
    input()