Coffee club accounts
====================

The accounting of the coffee club is managed wth the program
[ledger](https://www.ledger-cli.org/).  To see the balances:

    ledger -f journal.dat balance

which should show how much credit/debt each member has, how much money
in the savings account, and how much have we spent since ever.

The associated data file `journal.dat` is a plain text file and be
inspected easily by anyone.  Members joining and leaving the club are
comments on the file.  To list the current club members use:

    awk -f current-members.awk journal.dat


Ledger
------

We use the following top level accounts:

  * checking: this is the current balance.  We buy coffee from here,
    and we used to buy maintenance parts from here as well before we
    had a separate savings account.

  * savings: this is the account for long term expenses like parts,
    cleaning tablets, and repairs.

  * member: one for each club member.  If they go negative, they owe
    the club, if they go positive, they still have credit.  The
    sub-accounts use the member email address which we use as unique
    ids.

  * income: where members get money to pay us.  We don't care.

When a user leaves, his balance is moved into the checkings account.
This happens often because they left the department and did not notify
us.  They obviously have more important things on their minds at the
time.  Anyway, we just forgive them their debt by putting on the
checkings account for everyone else to pay next time.  And if they
have credit, that also gets in the checkings account and is split
among all remaining members.

Current members
---------------

We use `; joins EMAIL` and `; leaves EMAIL` comments in `journal.dat`
to keep track of the current members.  Their email addresses are used
as IDs.  We can then use a awk script to get the number of people we
should be charging:

    awk -f current-members.awk journal.dat | wc -l