FrontAccounting forum — Whats happened with Recurrent invoices?

Re: Whats happened with Recurrent invoices?

2017-12-16T02:40:50Z

When days = -1 and the day of the last sent date is 29, 30 and 31 which are part of valid dates after computation of $next if they become the last day of that month, this is what is desirable. If however, those $next dates are not valid, then they should be pushed to the last day of that month. The Karnaugh map of this logic on reduction just means irrespective of the day part of the last sent date, just push it to the last day of the computed $next date. he question is that how is the computation of the $next date to be undertaken for edge conditions. The "-1" according to the wiki is just a token to indicate the last date of the previous month as the $next date - so what is the logic needed to code it that way so that it will not have to rely on hindsight.

Re: Whats happened with Recurrent invoices?

2017-12-15T17:51:22Z

Yes, that sounds good.

Comment: Are 29, 30 & 31 'edge' cases?

Re: Whats happened with Recurrent invoices?

2017-12-15T05:35:04Z

Also we can make sure that if the Invoice Date becomes 29 to 31 we need to push it to the end of the month if it is invalid (like 31st Feb). That way, can we do away with the "-1" days by always choosing 31st of some valid / invalid month?

Re: Whats happened with Recurrent invoices?

2017-12-14T18:32:00Z

For me the expected results would be as follows:-

Test 3 0 1 05-12-16 1 05-01-17 05/12/2016 - 04/01/2017.
Test 3 0 1 05-12-16 2 05-02-17 05/01/2017 - 04/02/2017.
Test 3 0 1 05-12-16 3 05-03-17 05/02/2017 - 04/03/2017.

Test 4 0 1 29-12-16 1 29-01-17 29/12/2016 - 28/01/2017.
Test 4 0 1 29-12-16 2 28-02-17 29/01/2017 - 27/02/2017.
Test 4 0 1 29-12-16 3 29-03-17 28/02/2017 - 28/03/2017.
Test 4 0 1 29-12-16 4 29-04-17 29/03/2017 - 28/04/2017.

Test 4 0 1 30-12-16 1 30-01-17 30/12/2016 - 29/01/2017.
Test 4 0 1 30-12-16 2 28-02-17 30/01/2017 - 27/02/2017.
Test 4 0 1 30-12-16 3 30-03-17 28/02/2017 - 29/03/2017.
Test 4 0 1 30-12-16 4 30-04-17 30/03/2017 - 29/04/2017.

Test 4 0 1 31-12-16 1 31-01-17 31/12/2016 - 30/01/2017.
Test 4 0 1 31-12-16 2 28-02-17 31/01/2017 - 27/02/2017.
Test 4 0 1 31-12-16 3 31-03-17 28/02/2017 - 30/03/2017.
Test 4 0 1 31-12-16 4 30-04-17 31/03/2017 - 29/04/2017.
Test 4 0 1 31-12-16 5 31-05-17 30/04/2017 - 30/05/2017.

I think I have that right please check

As I said earlier We can state in the wiki that only start dates to the 28th of the month are permitted

Re: Whats happened with Recurrent invoices?

2017-12-14T17:39:25Z

The method of date calculation for add_months() has been hardcoded for
1 leap day each 4 years,
1 more leap day each 100 years and
1 less leap day every 400 years.
The number of days each month are looked up in an array in this manner.

This translates into the famous "What day would Christmas be in the year ####" as absolute day of Christmas for a known year + no. of years to required year from known year * 1.2496.

That is why I wanted the Gregorian year php function to be used. Even then I doubt this issue would get solved fully.

Let us first determine what we want for each of the 29 (non leap years), 30, 31 dates.

Re: Whats happened with Recurrent invoices?

2017-12-14T15:03:22Z

We may be getting a little confused with the objective,

The original code (before the above mods) functioned if 0 for days and 1 or more entered in months, the start date would then be the billing date going forward. So for dates from the 1st - 28th of the month this works fine, but what happens if you want the 29th, 30th or 31st? It all goes wrong in February (unless its a leap year for the 29th), and stays wrong in march onwards.

We can state in the wiki that only start dates to the 28th of the month are permitted, but...?

Re: Whats happened with Recurrent invoices?

2017-12-14T04:15:32Z

Shall we code so that:

Test expected    -1    1    31-12-2016        1    31-01-2017    31-12-2016 - 30-01-2017.

The last sent will then become 31-01-2017 ?

Re: Whats happened with Recurrent invoices?

2017-12-13T21:33:08Z

//new function calculate_next
function calculate_next($myrow)
{
    if ($myrow["last_sent"] == '0000-00-00')
        $next = sql2date($myrow["begin"]);
    else
        $next = sql2date($myrow["last_sent"]);
    if ($myrow['days'] == -1 && $myrow['monthly'] > 0) {
        // ignore months when days = -1
            $next = begin_month($next); // to later become last day of previous month
            $myrow['days']=0;
    }
    $next = add_months($next, $myrow['monthly']);
    $next = add_days($next, $myrow['days']);
    return add_days($next,-1);
}

is giving the same result

Test 9e -1 1 31-12-16 1 30-01-17 31/12/2016 - 29/01/2017.
Test 9e -1 1 31-12-16 2 27-02-17 30/01/2017 - 26/02/2017.
Test 9e -1 1 31-12-16 3 26-03-17 27/02/2017 - 25/03/2017.

Re: Whats happened with Recurrent invoices?

2017-12-11T23:32:18Z

Try this now:

function calculate_next($myrow)
{
    if ($myrow["last_sent"] == '0000-00-00')
        $next = sql2date($myrow["begin"]);
    else
        $next = sql2date($myrow["last_sent"]);
    if ($myrow['days'] == -1 && $myrow['monthly'] > 0) {
        // ignore months when days = -1
            $next = begin_month($next); // to later become last day of previous month
            $myrow['days']=0;
    }
    $next = add_months($next, $myrow['monthly']);
    $next = add_days($next, $myrow['days']);
    return add_days($next,-1);
}

Re: Whats happened with Recurrent invoices?

2017-12-11T17:27:46Z

function calculate_next($myrow)
{
    if ($myrow["last_sent"] == '0000-00-00')
        $next = sql2date($myrow["begin"]);
    else
        $next = sql2date($myrow["last_sent"]);
    if ($myrow['days'] == -1 && $myrow['monthly'] > 0) {
        // ignore months when days = -1
            $next = add_days(begin_month($next), -1); // last day of previous month
            $myrow['days']=0;
    }
    $next = add_months($next, $myrow['monthly']);
    $next = add_days($next, $myrow['days']);
    return add_days($next,-1);
}

gives

Test 9d -1 1 31-12-16 1 30-01-17 31/12/2016 - 29/01/2017.
Test 9d -1 1 31-12-16 2 27-02-17 30/01/2017 - 26/02/2017.
Test 9d -1 1 31-12-16 3 26-03-17 27/02/2017 - 25/03/2017.

Re: Whats happened with Recurrent invoices?

2017-12-11T15:28:53Z

From the wiki:

A days value of -1 together with a month value would be the last day in the previous month.

Hence we need a month value as well to get the period.

The function that can now be tried is:

function calculate_next($myrow)
{
    if ($myrow["last_sent"] == '0000-00-00')
        $next = sql2date($myrow["begin"]);
    else
        $next = sql2date($myrow["last_sent"]);
    if ($myrow['days'] == -1 && $myrow['monthly'] > 0) {
        // ignore months when days = -1
        $next = add_days(begin_month($next), -1); // last day of previous month
        $myrow['days']=0;
    }
    $next = add_months($next, $myrow['monthly']);
    $next = add_days($next, $myrow['days']);
    return add_days($next,-1);
}

Re: Whats happened with Recurrent invoices?

2017-12-11T15:01:57Z

With:-

function calculate_next($myrow)
{
    if ($myrow["last_sent"] == '0000-00-00')
        $next = sql2date($myrow["begin"]);
    else
        $next = sql2date($myrow["last_sent"]);
    if ($myrow['days'] == -1) {
        // ignore months when days = -1
            $next = add_days($next, 2); // <-- changed line
            $next = end_month($next);
            return $next;
    } else {
        $next = add_months($next, $myrow['monthly']);
        $next = add_days($next, $myrow['days']);
        return add_days($next,-1);
    }
}

I'm getting the following:-
Input to recurrent invoices Create and Print Recurrent Invoices
Name Days Monthly Begin Invoice # Invoice date Recurrent Invoice covers period
Test 1c 7 0 01-12-16 1 08-12-16 01/12/2016 - 07/12/2016.
Test 1c 7 0 01-12-16 2 15-12-16 08/12/2016 - 14/12/2016.
" " " " " " "
Test 1c 7 0 01-12-16 ~~12?~~ 23-02-17 16/02/2017 - 22/02/2017.
Test 1c 7 0 01-12-16 ~~13?~~ 02-03-17 23/02/2017 - 01/03/2017.

Test 2c 0 1 01-12-16 1 01-01-17 01/12/2016 - 31/12/2016.
Test 2c 0 1 01-12-16 2 01-02-17 01/01/2017 - 31/01/2017.
Test 2c 0 1 01-12-16 3 01-03-17 01/02/2017 - 28/02/2017.
Test 2c 0 1 01-12-16 4 01-04-17 01/03/2017 - 31/03/2017.

Test 5c 0 1 31-12-16 1 31-01-17 31/12/2016 - 30/01/2017.
Test 5c 0 1 31-12-16 2 28-02-17 31/01/2017 - 27/02/2017.
Test 5c 0 1 31-12-16 3 28-03-17 28/02/2017 - 27/03/2017.

Test 9 -1 0 31-12-16 1 30-12-16 31/12/2016 - 29/12/2016.
Test 9 -1 0 31-12-16 2 29-12-16 30/12/2016 - 28/12/2016.
Test 9 -1 0 31-12-16 3 28-12-16 29/12/2016 - 27/12/2016.

Re: Whats happened with Recurrent invoices?

2017-12-10T20:21:51Z

Ah... !
Ok, will retest with updated function, maybe today, probably tomorrow.

Re: Whats happened with Recurrent invoices?

2017-12-10T19:01:53Z

For 30 days it appears okay so we do not need to change that portion.

For -1, the invoice needs to be raised on the last day of the month for the period from the last day of the previous month to the day before the last day of the current month.

The new function replacement should be:

function calculate_next($myrow)
{
    if ($myrow["last_sent"] == '0000-00-00')
        $next = sql2date($myrow["begin"]);
    else
        $next = sql2date($myrow["last_sent"]);
    if ($myrow['days'] == -1) {
        // ignore months when days = -1
            $next = add_days($next, 2); // <-- changed line
            $next = end_month($next);
            return $next;
    } else {
        $next = add_months($next, $myrow['monthly']);
        $next = add_days($next, $myrow['days']);
        return add_days($next,-1);
    }
}

Re: Whats happened with Recurrent invoices?

2017-12-10T18:00:48Z

so with

//new function calculate_next
function calculate_next($myrow)
{
    if ($myrow['days'] == -1) {
// ignore months when days = -1
    $next = add_days($next, 1);
    $next = end_month($next);
    return $next;
} else {
    $next = add_months($next, $myrow['monthly']);
    $next = add_days($next, $myrow['days']);
    return add_days($next,-1);
}
}

I'm getting:-

Test 7 30 0 01-12-16 1 31-12-16 01/12/2016 - 30/12/2016.
Test 7 30 0 01-12-16 2 30-01-17 31/12/2016 - 29/01/2017.
Test 7 30 0 01-12-16 3 01-03-17 30/01/2017 - 28/02/2017.

Test 8 30 0 31-12-16 1 30-01-17 31/12/2016 - 29/01/2017.
Test 8 30 0 31-12-16 2 01-03-17 30/01/2017 - 28/02/2017.
Test 8 30 0 31-12-16 3 31-03-17 01/03/2017 - 30/03/2017.