+edit_invoice(){
+ id="$1"
+ if [ -f "invoices/$id" ]; then
+ read -r sender client date number vat vatrate<<-EOF
+ $(sed q "invoices/$id")
+ EOF
+ fi
+
+ [ "${date#date=}" -ge 0 ] 2>&- \
+ && date="$(date -d "@${date#date=}" +%F)" \
+ || date="$(date +%F)"
+ [ "${number#number=}" ] || number="number=$(date +%s)"
+ [ "${vatrate#vatrate=}" -ge 0 ] 2>&- || vatrate="vatrate=19"
+
+ cat <<-EOF
+ [form method="POST" action="/update_invoice"
+ [hidden "id" "$(HTML "$id")"]
+
+ [label Sender:]
+ [select name=sender
+ $(sender_list "${sender#sender=}")
+ ]
+
+ [label Client:]
+ [select name=client
+ $(client_list "${client#client=}")
+ ]
+
+ [label for=number Invoice Number:]
+ [input #number name=number value="$(UNSTRING "${number#number=}" |HTML)"]
+
+ [label for=date Date:]
+ [input #date name=date value="${date}" placeholder="YYYY-MM-TT"]
+
+ [radio "vat" "smallbusiness" #vatsb $([ "${vat#vat=}" = smallbusiness ] && printf checked) ]
+ [label for=vatsb Small business exemption from VAT]
+ [radio "vat" "nett" #vatnett $([ "${vat#vat=}" = nett ] && printf checked)]
+ [label for=vatnett Nett]<!--
+ -->[radio "vat" "gross" #vatgross $([ "${vat#vat=}" = gross ] && printf checked)]<!--
+ -->[label for=vatgross Gross]
+ [label for=vatrate VAT Rate: [input type=number name="vatrate" value="${vatrate#vatrate=}"]% ]
+
+ [submit "update" "update" Update]
+ ]
+ EOF
+}
+