#!/bin/bash
DATA_HOME="$XDG_DATA_HOME/bill-generator"
source "$XDG_CONFIG_HOME/bill-generator/ident"
# Need to be set to the installed location
TEMPLATE_1COL="$DATA_HOME/1col.template.mm"
TEMPLATE_2COL="$DATA_HOME/2col.template.mm"
INV_FILE="$DATA_HOME/last_invoice_number"

print_help() {
	echo "$(basename $0) -1 <hrs.csv> <Paying Company Name> [output file]"
	echo "$(basename $0) -2 <hrs.csv> <items.csv> <Paying Company Name> [output file]"
	echo ""
	echo "CSV files should be <name>,<value>."
	echo "CSV files should have no empty line at the end."
	echo "Paying company name is any string"
	echo "The output argument is optional and will by default output to invoice-<num>.pdf"
}
get_invoice_num() {
	# Increment a global invoice number
	INV_NUM=0
	if [[ -f $INV_FILE ]]; then
		INV_NUM=$(expr $(cat $INV_FILE) + 1)
	else
		INV_NUM=1
	fi
	echo $INV_NUM > $INV_FILE
	echo $INV_NUM
}
read_hrs_csv() {
	TMP=$(mktemp)
	# Parse the CSV into: Label;Hrs;Cost
	cat $1 | RATE=$RATE awk -F, '{ sum += $2 }; { print $1 ";" $2 ";" $2 * ENVIRON["RATE"] } END { print sum ";" sum * ENVIRON["RATE"] }' > $TMP
	echo $TMP
}
read_items_csv() {
	TMP=$(mktemp)
	cat $1 | awk -F, '{ sum += $2 }; { print $1 ";" $2 } END { print sum }' > $TMP
	echo $TMP
}

if [[ -z $1 ]]; then
	print_help
	exit
fi

export INVOICE_NUM=$(get_invoice_num)
OUTPUT="invoice-${INVOICE_NUM}.pdf"

HRS_TMP=$(read_hrs_csv $2)
export HRS_TOTAL=$(cat $HRS_TMP | tail -n 1)
export HRS_BODY=$(cat $HRS_TMP | head -n -1)

if [[ $1 = "-1" ]]; then
	if [[ ! -z $4 ]]; then
		OUTPUT=$4
	fi
	export COMPANY=$3
	envsubst < $TEMPLATE_1COL | groff -t -mm -T pdf > $OUTPUT
elif [[ $1 = "-2" ]]; then
	if [[ ! -z $5 ]]; then
		OUTPUT=$5
	fi
	HRS_COST=$(cat $HRS_TMP | tail -n 1 | awk -F";" '{ print $2 }')
	CONSUME_TMP=$(read_items_csv $3)
	CONSUME_COST=$(cat $CONSUME_TMP | tail -n 1 | awk -F";" '{ print $2 }')
	export ITEM_TOTAL=$(cat $CONSUME_TMP | tail -n 1)
	export ITEM_BODY=$(cat $CONSUME_TMP | head -n -1)
	export TOTAL=$(A=$HRS_COST B=$ITEM_TOTAL awk 'BEGIN{ print ENVIRON["A"] + ENVIRON["B"] }')
	export COMPANY=$4
	envsubst < $TEMPLATE_2COL | groff -t -mm -T pdf > $OUTPUT
else
	echo First arg should be either -1 or -2
fi