%
% Copyright (c) 2021-2026 Zeping Lee
% Released under the MIT License.
% Repository: https://github.com/zepinglee/citeproc-lua
%

\NeedsTeXFormat{LaTeX2e}

\RequirePackage{expl3}
\RequirePackage{xparse}

\ProvidesExplPackage {citation-style-language} {2026-03-24} {0.9.2}
  {Citation Style Language for LaTeX}

\RequirePackage { url }


\prop_gput:Nnn \g_msg_module_name_prop { citation-style-language } { CSL }
\prop_gput:Nnn \g_msg_module_type_prop { citeproc } { Module }

\msg_new:nnn { citeproc } { citeproc-error } {#1}
\msg_new:nnn { citeproc } { citeproc-warning } {#1}


% Check incompatible packages
\msg_new:nnn { citation-style-language } { incompatible-package }
  { Package~ '#1'~ is~ incompatible~ with~ 'citation-style-language'. }

\clist_map_inline:nn
  {
    babelbib , biblatex , bibtopic , bibunits , chapterbib ,
    cite , citeref , inlinebib , jurabib , mcite , mciteplus ,
    multibib , natbib , splitbib
  }
  {
    \hook_gput_code:nnn { package / #1 / before } { . }
      { \msg_error:nnn { citation-style-language } { incompatible-package } {#1} }
  }


% Load Lua module in LuaTeX
\sys_if_engine_luatex:T
  {
    \lua_now:n
      {
        citeproc_manager = require("citeproc-manager")
        csl_citation_manager = citeproc_manager.CslCitationManager:new()
      }
  }


% Global options

\NewDocumentCommand \cslsetup { m }
  { \keys_set:nn { csl } {#1} }


\bool_new:N \l__csl_regression_test_bool
\tl_new:N \g__csl_global_style_tl
\tl_new:N \l__csl_style_tl
\newcommand \csl@style {}  % For latex2e interface
\tl_new:N \l__csl_class_tl  % TODO: This should be removed
\bool_new:N \g__csl_global_note_class_bool
\bool_new:N \l__csl_note_bool
\clist_new:N \g__csl_global_bib_resources_clist
\clist_new:N \l__csl_bib_resources_clist
\tl_new:N \g__csl_global_locale_tl
\tl_new:N \l__csl_locale_tl
\bool_new:N \g__csl_use_bbl_bool
\bool_new:N \g__csl_use_lua_module_bool
\bool_new:N \l__csl_back_ref_bool
\str_new:N \l__csl_back_ref_type_str
% Citation formatting
\tl_new:N \l__csl_prefix_separator_tl
\tl_new:N \l__csl_suffix_separator_tl
% Bibliography formatting
\tl_new:N \bibsection
\tl_new:N \l__csl_bib_font_tl
\bool_new:N \l__csl_bib_entry_page_break_bool
\dim_new:N \l__csl_bib_label_sep_dim
\tl_new:N \l__csl_bib_item_sep_tl
\tl_new:N \l__csl_bib_name_sep_tl
\tl_new:N \l__csl_bib_block_sep_tl
\tl_new:N \l__csl_bib_par_indent_tl
\tl_new:N \l__csl_bib_hang_tl
\str_new:N \l__csl_bib_ref_section_str


\keys_define:nn { csl }
  {
    regression-test .bool_set:N = \l__csl_regression_test_bool ,
    style .code:n =
      {
        \tl_set:Nn \l__csl_style_tl {#1}
        \renewcommand \csl@style {#1}
        \tl_gset:Nn \g__csl_global_style_tl {#1}
      } ,
    class .code:n = {} ,  % Deprecated, should be removed in the next release.
    bib-resource .code:n =
      {
        \clist_set:Nn \l__csl_bib_resources_clist {#1}
        \clist_gset_eq:NN \g__csl_global_bib_resources_clist \l__csl_bib_resources_clist
      } ,
    locale .code:n =
      {
        \tl_set:Nn \l__csl_locale_tl {#1}
        \tl_gset:Nn \g__csl_global_locale_tl {#1}
      } ,
    use-bbl .bool_gset:N = \g__csl_use_bbl_bool ,
    backref .choices:nn =
      { true, page, section, false }
      { \exp_args:NV \__csl_set_back_ref:n \l_keys_choice_tl } ,
    % Citation formatting
    prefix-separator .tl_set:N = \l__csl_prefix_separator_tl ,
    suffix-separator .tl_set:N = \l__csl_suffix_separator_tl ,
    % Bibliography formatting
    bib-section .tl_set:N = \bibsection ,
    bib-font .tl_set:N = \l__csl_bib_font_tl ,
    bib-entry-page-break .bool_set:N = \l__csl_bib_entry_page_break_bool ,
    bib-label-sep .dim_set:N = \l__csl_bib_label_sep_dim ,
    bib-item-sep .tl_set:N = \l__csl_bib_item_sep_tl ,
    bib-name-sep .tl_set:N = \l__csl_bib_name_sep_tl ,
    bib-after-name-sep .tl_set:N = \l__csl_bib_after_name_sep_tl ,
    bib-par-indent .tl_set:N = \l__csl_bib_par_indent_tl ,
    bib-hang .tl_set:N = \l__csl_bib_hang_tl ,
    % ref section
    ref-section .choices:nn =
      { none, part, chapter, chapter+, section, section+, subsection, subsection+ }
      { \str_set:NV \l__csl_bib_ref_section_str \l_keys_choice_tl } ,
  }

\cs_new:Npn \__csl_set_back_ref:n #1
  {
    \str_if_eq:nnTF {#1} { false }
      {
        \bool_set_false:N \l__csl_back_ref_bool
      }
      {
        \bool_set_true:N \l__csl_back_ref_bool
        \str_if_eq:nnTF {#1} { true }
          { \str_set:Nn \l__csl_back_ref_type_str { page } }
          { \str_set:Nn \l__csl_back_ref_type_str {#1} }
      }
  }

% Default settings
\keys_set:nn { csl }
  {
    use-bbl = false ,
    backref = false ,
    prefix-separator = { ~ } ,
    suffix-separator = { , ~ } ,
    bib-entry-page-break = true ,
    bib-label-sep = { \labelsep } ,
    bib-name-sep = { 0 pt } ,
    bib-after-name-sep = { 0 pt } ,
    bib-par-indent = { \parindent } ,
    bib-hang = { 1 em } ,
    ref-section = none ,
  }


\ProcessKeyOptions [ csl ]


\hook_gput_code:nnn { enddocument } { . }
  {
    \bool_if:NT \g__csl_use_bbl_bool
      {
        \sys_if_engine_luatex:T
          {
            \file_if_exist:nF { \jobname .bbl }
              { \lua_now:e { csl_citation_manager:write_bbl("\jobname") } }
          }
      }
  }


\DeclareDocumentCommand \bibliographystyle { m }
  {
    \__csl_if_preamble:F
      { \__csl_write_aux_bibstyle:n {#1} }
    \tl_set:Nn \l__csl_style_tl {#1}
  }

\tl_new:N \g__csl_aux_bibstyle_tl
\cs_new:Npn \csl@aux@style #1#2
  {
    \str_if_eq:nnT {#1} { 0 }
      { \tl_gset:Nn \g__csl_aux_bibstyle_tl {#2} }
  }


% Write to an empty `.ccf` file for use with latexmk
\sys_if_engine_luatex:F
  {
    \iow_new:N \l__csl_ccf_iow
    \iow_open:Nn \l__csl_ccf_iow { \c_sys_jobname_str .ccf }
    \iow_now:Ne \l__csl_ccf_iow
      {
        \c_percent_str \c_space_tl This~ file~ is~ generated~ by~
        citation-style-language~ package. \iow_newline:
        \c_percent_str \c_space_tl Its~ main~ purpose~ is~ to~ be~ recognized~
        by~ latexmk.
      }
    \iow_close:N \l__csl_ccf_iow
  }


% Load other modules
\input { citation-style-language-init.sty }
\input { citation-style-language-data.sty }
\input { citation-style-language-cite.sty }
\input { citation-style-language-bib.sty }
\input { citation-style-language-compatible.sty }


\endinput
