%
% Copyright (C) 2024 Marei Peischl <marei@peitex.de>
% ---------------------------------------------------------
%
% This file may be distributed and/or modified under the
% conditions of the LaTeX Project Public License, either version 1.3c
% of this license or (at your option) any later version.
% The latest version of this license is in:
%
%    http://www.latex-project.org/lppl.txt
%
% and version 1.3c or later is part of all distributions of LaTeX
% version 2008-05-04 or later.
%
\ProvidesExplPackage{zugferd-invoice}{2024-10-23}{0.9}{Invoice wrapper example package for the factur-x to create ZUGFerD invoices}

\keys_define:nn {zugferd/invoice}{
	default-vat .tl_set:N =  \defaultVAT,
	default-vat .initial:n = 19,
	format .code:n = \PassOptionsToPackage{format=#1}{zugferd},
	format .initial:n = xrechnung3.0,
}

\ProcessKeyOptions[zugferd/invoice]

\msg_new:nnnn {ptxcd/zugferd} {not-for-production} {
	This~package~is~intented~to~be~an~example~for~a~possible~implementation~to~use~the~zugferd~package~for~invoicing.\\
	As~this~integrates~a~lot~with~the~visual~structure~of~your~invoice~this~should~not~be~used~directly~but~may~be~an~example~for~your~own~package.
}{See~zugferd~documentation~for~instructions~concerning~the~interfaces~used~in~this~file.}
\msg_warning:nn  {ptxcd/zugferd} {not-for-production}

\RequirePackage{scrletter}
\RequirePackage{ragged2e}
\RequirePackage{zugferd}
\RequirePackage{babel}

% e.g. use comma as output decimal marker if german
\addto\extrasgerman{\sisetup{locale=DE}}
\addto\extrasngerman{\sisetup{locale=DE}}% for backwards compatibility

\RequirePackage{xltabular}
\RequirePackage{booktabs}

\newcounter{invoiceitem}
\seq_new:N  \g__ptxcd_VAT_rates_seq 

% InitVAT accepts 2 Arguments
% Percentage + Tax Type Code the latter one is set to S as a default
\NewDocumentCommand{\InitVAT}{mO{S}}{
	\seq_gput_right:Nn \g__ptxcd_VAT_rates_seq {#1}
	\fp_new:c {g__ptxcd_invoice_sum_vat#1_fp}
	\fp_new:c {g__ptxcd_invoice_base_vat#1_fp}
	\cs_new:cn {__ptxcd_invoice_type_code#1:} {#2}
}

%Initialize VAT rates for (5),7,(16) and 19 % VAT
%\InitVAT{16}
\InitVAT{19}
%\InitVAT{5}
\InitVAT{7}

% Tax initialisation with a different Code than S in this example Syntax would be
% \InitVAT{0}[AE]


\newcommand*{\SetDefaultVAT}[1]{\def\defaultVAT{#1}}


\seq_new:N \l__ptxcd_invoice_items_seq

% Auxiliary macro to allow setting the Invoice items at a different position as they are printed later
\NewDocumentCommand{\AddInvoiceItem}{D<>{}O{\defaultVAT}mmm}{
	\seq_put_right:Nn \l__ptxcd_invoice_items_seq {
		{#2}{#3}{#4}{#5}{#1}
	}
}

\newcolumntype{P}{r<{\PrintTableCurrency}}

\fp_new:N \g__ptxcd_invoice_sum_fp
\fp_new:N \g__ptxcd_invoice_total_fp
\fp_new:N \g__ptxcd_tax_total_fp
\fp_new:N \g__ptxcd_invoice_item_fp
\fp_new:N  \g__ptxcd_invoice_item_vat_fp
\fp_new:N \g__ptxcd_invoice_sum_vat_fp

\newcommand*{\PrintInvoiceTabular}{
\bool_gset_true:N \g_ptxcd_first_run_bool
	\begin{ZUGFeRD}
	\sisetup{round-precision=2,round-mode=places,round-pad=false,table-number-alignment=right,minimum-decimal-digits=2,mode=text}
	\begin{xltabular}{\linewidth}{@{}rS[round-precision=1,table-format=2.1]>{\RaggedRight}XPP@{}}
	\toprule[\lightrulewidth]
	\noalign{\global\let\PrintTableCurrency\relax}%
	\small\emph{Pos.}&\small\emph{Std.}&\small\emph{Beschreibung}&\small\emph{Einzelpreis}&\small\emph{Gesamtpreis}\\\midrule[\heavyrulewidth]
	\noalign{\global\let\PrintTableCurrency\TableCurrency}%
	\endhead
	\bottomrule[\lightrulewidth]\multicolumn{5}{@{}p{\textwidth}@{}}{\strut\hspace*{\fill}\footnotesize Fortsetzung auf der nächsten Seite}\endfoot
	\bottomrule\endlastfoot
% Only write xml for the first run of the tabular.
	\fp_compare:nNnF {\g__ptxcd_invoice_sum_fp} = {\c_zero_dim} {
		\fp_gzero:N \g__ptxcd_invoice_sum_fp
		\zugferd_disable_XML_interfaces:
	}
	\seq_map_inline:Nn  \g__ptxcd_VAT_rates_seq  {
		\fp_gzero:c  {g__ptxcd_invoice_sum_vat##1_fp}
		\fp_gzero:c {g__ptxcd_invoice_base_vat##1_fp}
	}
	\fp_gzero:N \g__ptxcd_invoice_sum_fp
	\seq_map_inline:Nn \l__ptxcd_invoice_items_seq {
		 \PrintInvoiceItem##1
	}
	\tabularnewline
	\noalign{\skip_vertical:n {-\ht\strutbox-\dp\strutbox}}%offset for extra empty row of mapping
	\midrule[\heavyrulewidth]
	\PrintInvoiceTotal
	\end{xltabular}
	\end{ZUGFeRD}
}

\newcommand*{\PrintInvoiceTotal}{
	\zugferd_startInvoiceSums:
	\fp_gset:Nn \g__ptxcd_invoice_total_fp { \g__ptxcd_invoice_sum_fp}
	\fp_gzero:N \g__ptxcd_tax_total_fp
	\PrintInvoiceSum{netto}{\fp_use:N  \g__ptxcd_invoice_sum_fp}
	\seq_map_inline:Nn \g__ptxcd_VAT_rates_seq  {
		\fp_compare:nNnF {\fp_use:c {g__ptxcd_invoice_sum_vat##1_fp}} = {0} {
			\zugferd_write_TaxEntry:nnnn  {\use:c {__ptxcd_invoice_type_code##1:}} {##1} {\fp_use:c {g__ptxcd_invoice_base_vat##1_fp}} {\fp_use:c {g__ptxcd_invoice_sum_vat##1_fp}}
			\fp_gadd:Nn \g__ptxcd_tax_total_fp {\fp_use:c {g__ptxcd_invoice_sum_vat##1_fp}}
			\PrintVatSum[{\fp_use:c {g__ptxcd_invoice_base_vat##1_fp}}]{##1 }{\fp_use:c {g__ptxcd_invoice_sum_vat##1_fp}}
		}
	}
	\PrintInvoiceSum{brutto}{\fp_eval:n {\g__ptxcd_tax_total_fp +  \g__ptxcd_invoice_total_fp }}
	% TODO add support for allowance, chargeTotal, and prepaid
	 \zugferd_write_Summation:nnnnnnnn
		{\fp_use:N  \g__ptxcd_invoice_sum_fp}% LineTotalAmount
		{0} %ChargeTotalAmount
		{0} %AllowanceTotalAmount
		{\fp_use:N  \g__ptxcd_invoice_sum_fp} %TaxBasisTotalAmount
		{\fp_use:N \g__ptxcd_tax_total_fp} %TaxTotalAmount
		{\fp_eval:n {\g__ptxcd_tax_total_fp +  \g__ptxcd_invoice_total_fp }} %GrandTotalAmount
		{0} % TotalPrepaidAmount
		{\fp_eval:n {\g__ptxcd_tax_total_fp +  \g__ptxcd_invoice_total_fp }} %DuePayableAmount = GrandTotalAmount - TotalPrepaidAmount
	\zugferd_stopInvoiceSums:
}

%Ausgabe der einzelnen Rechnungspositionen
\newcommand*{\PrintInvoiceItem}[5]{%
	\stepcounter{invoiceitem}%
	\theinvoiceitem%Positionsnummer
	\fp_gset:Nn \g__ptxcd_invoice_item_vat_fp  {#2 * (#1/100) * #4}
	\fp_gset:Nn \g__ptxcd_invoice_item_fp  {#2 * #4}
	\fp_gadd:cn {g__ptxcd_invoice_base_vat#1_fp} {\g__ptxcd_invoice_item_fp}
	\fp_gadd:cn {g__ptxcd_invoice_sum_vat#1_fp} {\g__ptxcd_invoice_item_vat_fp}
	\fp_gadd:Nn \g__ptxcd_invoice_sum_fp {\g__ptxcd_invoice_item_fp}
	
	% optionen position nummer name einzel-preis anzahl gesamtpreis	
	\zugferd_write_Item:ennnnnn {tax/rate=#1, tax/category=\use:c {__ptxcd_invoice_type_code#1:},#5} {\theinvoiceitem} {} {#3} {#4} {#2} {\fp_use:N \g__ptxcd_invoice_item_fp}
	
	&#2% Anzahl
	&#3\space(\printVAT{#1}~MwSt.)% Beschreibung mit Angabe der MwSt, in Klammern
	&\num{#4}%\num[round-mode=places,output-decimal-marker={,},round-pad = false]{#4}\tl_show:n {#4}%Einzelpreis
	&\exp_args:Nx \num{\fp_use:N \g__ptxcd_invoice_item_fp}
	\tabularnewline
}



\newcommand*{\PrintInvoiceSum}[2]{
	\PrintSum{\csname invoicesum#1name\endcsname}{#2}
}

\newcommand*{\PrintVatSum}[3][]{
	\PrintSum{\invoicesumvatname[#1]{#2}}{#3}
}

\newcommand*{\invoicesumvatname}[2][]{MwSt.~\printVAT{#2}\tl_if_empty:nF {#1} {\space(\num[round-precision=2]{#1}\TableCurrency)}}
\renewcommand*{\theinvoiceitem}{\int_compare:nNnT {\value{invoiceitem}}<{10}{0}\arabic{invoiceitem}}

\newcommand*{\PrintSum}[2]{
	&&\multicolumn{1}{r}{#1\invoicesumseparator}&\multicolumn{1}{l}{}&\exp_args:Nx \num {#2}\tabularnewline
}

\ExplSyntaxOff

\newcommand*{\invoicesumnettoname}{Summe (Netto)}
\newcommand*{\invoicesumbruttoname}{Summe (Brutto)}
\newcommand*{\invoicesumseparator}{:\space}

\newcommand*{\TableCurrency}{\,€}
\newcommand*{\printVAT}[1]{\num[round-mode=none]{#1}\,\%}

\newcommand*{\PrintPositionenVAT}[5]{%
	\stepcounter{invoiceitem}%
	\theinvoiceitem&#1&#2\space(\printVAT{#3})&#4&#5\tabularnewline
}

\endinput