#!/usr/bin/perl 

# Copyright (c) 2020 Freda Bundchen

# Permission to use, copy, modify, and distribute this software for any
# purpose with or without fee is hereby granted, provided that the above
# copyright notice and this permission notice appear in all copies.
#
# THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
# OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

use warnings;
use strict;

use Getopt::Std qw(getopts);

our ($opt_I);

my %banks = (
    "capital_one_credit"    => \&import_capital_one_credit,
    "chase_credit"          => \&import_chase_credit,
    "optum_hsa"             => \&import_optum_hsa,
    "sparkasse_camt"        => \&import_sparkasse_camt,
    "wellsfargo"            => \&import_wellsfargo,
);

# === SUBROUTINES  =====================================================

sub import_chase_credit ($$$) {
	my ($account, $csv_account, $line) = @_;
	my ($trans_date, $post_date, $description, $category,
	    $type, $amount) = split /,/, $line;
	my ($debit, $credit);
	$post_date =~ s#(\d+)/(\d+)/(\d+)#$3$1$2#; 
	($amount, $debit, $credit) =
	    get_accounts_by_amount_sign($amount, $account,
	    $csv_account);
	return ($post_date, $amount, $debit, $credit, $description);
}

sub import_capital_one_credit ($$$) {
	my ($account, $csv_account, $line) = @_;
	my ($trans_date, $post_date, $card_num,
	    $description, $category, $csv_debit,
	    $csv_credit) = split /,/, $line;
	$post_date =~ s/(\d+)-(\d+)-(\d+)/$1$2$3/; 
	my ($amount, $debit, $credit) = 
	    get_accounts_by_csv_col($account, $csv_account,
	    $csv_debit, $csv_credit);
	return ($post_date, $amount, $debit, $credit, $description);
}

sub import_optum_hsa ($$$) {
        my ($account, $csv_account, $line) = @_;
        my ($date, $description, $amount,
            $type) = split /,/, $line;
	my ($debit, $credit);
	$date =~ s/(\d+)-(\d+)-(\d+)/$1$2$3/;
	$amount =~ s/\$//;
	($amount, $debit, $credit) =
	    get_accounts_by_amount_sign($amount, $account,
	    $csv_account);
	return ($date, $amount, $debit, $credit, $description);
}

sub import_sparkasse_camt ($$$) {
        my ($account, $csv_account, $line) = @_;
	my @fields;
	$_ = $line;
	push @fields, $1 while s/"([^"]*)";?//;
	$_ eq "" or die "CAMT parse error before $_ in $line";
	@fields == 17 or die "not 17 but @fields fields: $line";
	$fields[1] =~ s/^(\d\d)\.(\d\d)\.(\d\d)$/20$3$2$1/
	    or die "date parse error: $line";
	$fields[14] =~ s/,/./;
	return $fields[1],
	    get_accounts_by_amount_sign($fields[14], $account, $csv_account),
	    (join ' ', $fields[11], $fields[4]);
}

sub import_wellsfargo ($$$) {
	my ($account, $csv_account, $line) = @_;
	$line =~
	    m#^"(\d+)/(\d+)/(\d+)","(-?\d+\.\d+)","\*","","(.*?)"$# or
	    die "parse error: $line" ;
	my ($month, $day, $year, $amount, $description) =
	    ($1, $2, $3, $4, $5);
	return "$year$month$day",
	    get_accounts_by_amount_sign($amount, $account, $csv_account),
	    $description;
}

sub get_accounts_by_amount_sign ($$$) {
	my ($amount, $account, $csv_account) = @_;
	my ($debit, $credit);
	if ($amount <= 0) {
		$amount = substr $amount, 1;
		$credit = $csv_account;	
		$debit = $account;
	} else {
		$debit = $csv_account;	
		$credit = $account;
	}
	return ($amount, $debit, $credit);
}

sub get_accounts_by_csv_col ($$$$) {
	my ($account, $csv_account, $csv_debit, $csv_credit) = @_;
	my ($amount, $debit, $credit);
	if ($csv_debit eq "") {
		$amount = $csv_credit;
		$credit = $account;
		$debit = $csv_account;
	} else {
		$amount = $csv_debit;
		$credit = $csv_account;
		$debit = $account;
	}
	return ($amount, $debit, $credit);
}

sub usage () {
	printf STDERR "usage: %s -I accountname csvfilename\n", $0;
	exit 1;
}

# === MAIN PROGRAM =====================================================

getopts 'I:' or usage;
unless ($opt_I) {
	warn "The option -I is required.";
	usage;
}
my $account_name = $opt_I;
$banks{$account_name} or die "unknown accountname: $account_name";

# Parse the configuration file.
my $fn = "import_" . $account_name . ".txt";
open my $in, '<', $fn or die "$fn: $!";
my ($csv_account, $delim, $header, @compiled);
while (<$in>) {
	chomp;
	next if /^(?:#|$)/;
	my $line = $_;
	if (/^ACCOUNT\s+(\S+)$/) {
		$csv_account and die "duplicate ACCOUNT line: $1";
		$csv_account = $1;
		next;
	}
	if (/^DELIM\s+(\S)$/) {
		$delim and die "duplicate DELIM line: $1";
		$delim = $1;
		next;
	}
	if (/^HEADER\s+(.*)$/) {
		$header and die "duplicate HEADER line: $1";
		$header = $1;
		next;
	}
	$delim or die "no DELIM line in $fn";
	s/^(.*)$delim\s+(\d+)\s+(\S+)// or
	    die "$fn import parse error: $line";
	push @compiled, {
		re => [map { qr/$_/ } split /$delim/, $1],
		ac => $2,
		id => $3,
	};
}
close $in;
$csv_account or die "no ACCOUNT line in $fn";

# Parse the CSV file from the bank.
while (<>) {
	chomp;
	next if (/^$/);
	my $line = $_;
	if ($header) {
		$line eq $header
		    or die "expected HEADER $header\nbut got $line";
		undef $header;
		next;
	}
	my @fields = split /$delim/, $line;
	my $matches = 0;
	my ($account, $booking);
	foreach my $selector (@compiled) {
		$matches = 1;
		for (my $i = 0; $i <= $#{$selector->{re}}; $i++) {
			next if $fields[$i] =~ $selector->{re}[$i];
			$matches = 0;
			last;
		}
		if ($matches) {
			$account = $selector->{ac};
			$booking = $selector->{id};
			last;
		}
	}
	$matches or die "unmatched CSV line: $line";
	my ($date, $amount, $debit, $credit, $description) =
	    $banks{$account_name}->($account, $csv_account, $line);
	$date && $amount && $debit && $credit && $description
	    or die "import parse error: $line";
	$description =~ s/#//g;
	print "$date $booking $debit $credit $amount $description\n";
}