%% texchanges.sty
%% LaTeX-native track changes for human and AI-assisted review.
%% Copyright (C) 2026 Phuc Nguyen
%%
%% This work 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. This work has the LPPL maintenance status
%% "maintained". The Current Maintainer is Phuc Nguyen.
\NeedsTeXFormat{LaTeX2e}[2020-10-01]
\ProvidesExplPackage{texchanges}{2026/08/15}{0.2.3}{LaTeX-native track changes}

\RequirePackage{xparse}
\RequirePackage{l3keys2e}

\ExplSyntaxOn

% --------------------------------------------------------------------------
% Package state and options
% --------------------------------------------------------------------------
\tl_new:N \g_tx_mode_tl
\tl_new:N \g_tx_preset_tl
\tl_new:N \g_tx_added_style_tl
\tl_new:N \g_tx_deleted_style_tl
\tl_new:N \g_tx_highlight_style_tl
\tl_new:N \g_tx_comment_style_tl
\tl_new:N \g_tx_author_style_tl
\tl_new:N \g_tx_author_position_tl
\tl_new:N \g_tx_author_text_tl
\tl_new:N \g_tx_default_color_tl
\tl_new:N \g_tx_compat_tl
\tl_new:N \g_tx_prefix_strategy_tl
\tl_new:N \g_tx_loc_ext_tl
\tl_new:N \g_tx_soc_ext_tl
\bool_new:N \g_tx_color_bool
\bool_new:N \g_tx_pending_bool
\bool_new:N \g_tx_todonotes_loaded_bool
\dim_new:N \g_tx_truncate_width_dim
\dim_new:N \g_tx_summary_width_dim

\tl_gset:Nn \g_tx_mode_tl { review }
\tl_gset:Nn \g_tx_preset_tl { texchanges }
\tl_gset:Nn \g_tx_added_style_tl { uline }
\tl_gset:Nn \g_tx_deleted_style_tl { sout }
\tl_gset:Nn \g_tx_highlight_style_tl { background }
\tl_gset:Nn \g_tx_comment_style_tl { inline }
\tl_gset:Nn \g_tx_author_style_tl { superscript }
\tl_gset:Nn \g_tx_author_position_tl { right }
\tl_gset:Nn \g_tx_author_text_tl { id }
\tl_gset:Nn \g_tx_default_color_tl { blue }
\tl_gset:Nn \g_tx_compat_tl { none }
\tl_gset:Nn \g_tx_prefix_strategy_tl { ifneeded }
\tl_gset:Nn \g_tx_loc_ext_tl { txc }
\tl_gset:Nn \g_tx_soc_ext_tl { txs }
\bool_gset_true:N \g_tx_color_bool
\dim_gset:Nn \g_tx_truncate_width_dim { .6\textwidth }
\dim_gset:Nn \g_tx_summary_width_dim { .3\textwidth }

\cs_new_protected:Npn \tx_apply_preset:n #1
  {
    \tl_gset:Nn \g_tx_preset_tl {#1}
    \bool_gset_true:N \g_tx_color_bool
    \str_case:nnF {#1}
      {
        {texchanges}{\tl_gset:Nn \g_tx_added_style_tl {uline} \tl_gset:Nn \g_tx_deleted_style_tl {sout}}
        {default}{\tl_gset:Nn \g_tx_added_style_tl {colored} \tl_gset:Nn \g_tx_deleted_style_tl {sout}}
        {underlined}{\tl_gset:Nn \g_tx_added_style_tl {uline} \tl_gset:Nn \g_tx_deleted_style_tl {sout} \tl_gset:Nn \g_tx_highlight_style_tl {uwave}}
        {bfit}{\tl_gset:Nn \g_tx_added_style_tl {bf} \tl_gset:Nn \g_tx_deleted_style_tl {it}}
        {nocolor}{\bool_gset_false:N \g_tx_color_bool \tl_gset:Nn \g_tx_added_style_tl {uline} \tl_gset:Nn \g_tx_deleted_style_tl {sout} \tl_gset:Nn \g_tx_highlight_style_tl {uwave}}
      }
      {\PackageWarning{texchanges}{Unknown~markup~preset~'#1';~using~texchanges}}
  }

\keys_define:nn { tx/package }
  {
    review .code:n = \tl_gset:Nn \g_tx_mode_tl {review},
    draft .code:n = \tl_gset:Nn \g_tx_mode_tl {review},
    final .code:n = \tl_gset:Nn \g_tx_mode_tl {final},
    original .code:n = \tl_gset:Nn \g_tx_mode_tl {original},
    mode .choices:nn = {review,final,original} {\tl_gset:Nx \g_tx_mode_tl {\l_keys_choice_tl}},
    markup .code:n = \tx_apply_preset:n {#1},
    addedmarkup .tl_gset:N = \g_tx_added_style_tl,
    deletedmarkup .tl_gset:N = \g_tx_deleted_style_tl,
    highlightmarkup .tl_gset:N = \g_tx_highlight_style_tl,
    commentmarkup .tl_gset:N = \g_tx_comment_style_tl,
    authormarkup .tl_gset:N = \g_tx_author_style_tl,
    authormarkupposition .tl_gset:N = \g_tx_author_position_tl,
    authormarkuptext .tl_gset:N = \g_tx_author_text_tl,
    defaultcolor .tl_gset:N = \g_tx_default_color_tl,
    compat .choices:nn = {none,changes} {\tl_gset:Nx \g_tx_compat_tl {\l_keys_choice_tl}},
    commandnameprefix .tl_gset:N = \g_tx_prefix_strategy_tl,
    xcolor .code:n = \PassOptionsToPackage{#1}{xcolor},
    ulem .code:n = \PassOptionsToPackage{#1}{ulem},
    todonotes .code:n = \PassOptionsToPackage{#1}{todonotes},
    truncate .code:n = \PassOptionsToPackage{#1}{truncate},
    unknown .code:n = \PackageWarning{texchanges}{Unknown~option~'\l_keys_key_str'~ignored}
  }
\ProcessKeysOptions { tx/package }
\exp_args:NV \tx_apply_preset:n \g_tx_preset_tl

\PassOptionsToPackage{normalem}{ulem}
\RequirePackage{xcolor}
\RequirePackage{ulem}
\RequirePackage{truncate}
\RequirePackage{soul}
\providecommand\phantomsection{}

\str_if_eq:VnT \g_tx_comment_style_tl {todo}
  {\RequirePackage{todonotes}\bool_gset_true:N \g_tx_todonotes_loaded_bool}

\definecolor{texchangesAdded}{HTML}{0057B8}
\definecolor{texchangesRemoved}{HTML}{C62828}
\definecolor{texchangesComment}{HTML}{A54800}
\definecolor{texchangesHighlight}{HTML}{FFF2A8}

% --------------------------------------------------------------------------
% Authors, localization, and per-change metadata
% --------------------------------------------------------------------------
\prop_new:N \g_tx_author_name_prop
\prop_new:N \g_tx_author_color_prop
\seq_new:N \g_tx_author_seq
\prop_new:N \g_tx_seen_id_prop
\prop_new:N \g_tx_counts_prop
\prop_new:N \l_tx_report_counts_prop
\tl_new:N \g_tx_anonymous_name_tl
\tl_gset:Nn \g_tx_anonymous_name_tl {anonymous}
\seq_gput_right:Nn \g_tx_author_seq {anonymous}
\prop_gput:Nnn \g_tx_author_name_prop {anonymous} {anonymous}
\prop_gput:NnV \g_tx_author_color_prop {anonymous} \g_tx_default_color_tl

\tl_new:N \l_tx_author_tl
\tl_new:N \l_tx_id_tl
\tl_new:N \l_tx_comment_tl
\tl_new:N \l_tx_status_tl
\tl_new:N \l_tx_label_tl
\tl_new:N \l_tx_color_tl
\tl_new:N \l_tx_type_tl
\tl_new:N \l_tx_excerpt_tl
\bool_new:N \l_tx_legacy_label_bool

\keys_define:nn { tx/change }
  {
    author .tl_set:N = \l_tx_author_tl,
    id .tl_set:N = \l_tx_id_tl,
    changeid .meta:n = {id={#1}},
    comment .tl_set:N = \l_tx_comment_tl,
    status .choices:nn = {pending,accepted,rejected} {\tl_set:Nx \l_tx_status_tl {\l_keys_choice_tl}},
    unknown .code:n = \PackageError{texchanges}{Unknown~change~key~'\l_keys_key_str'}{Use~author,~id,~comment,~or~status.}
  }
\keys_define:nn { tx/compat-change }
  {
    id .tl_set:N = \l_tx_author_tl,
    changeid .tl_set:N = \l_tx_id_tl,
    comment .tl_set:N = \l_tx_comment_tl,
    status .choices:nn = {pending,accepted,rejected} {\tl_set:Nx \l_tx_status_tl {\l_keys_choice_tl}},
    unknown .code:n = \PackageError{texchanges}{Unknown~compatibility~key~'\l_keys_key_str'}{Use~id,~changeid,~comment,~or~status.}
  }
\keys_define:nn { tx/author }
  {
    name .tl_set:N = \l_tmpa_tl,
    color .tl_set:N = \l_tmpb_tl
  }

\cs_new_protected:Npn \tx_define_author:nn #1#2
  {
    \tl_set:Nn \l_tmpa_tl {#2}
    \tl_set_eq:NN \l_tmpb_tl \g_tx_default_color_tl
    \keys_set:nn {tx/author}{#1}
    \seq_if_in:NnF \g_tx_author_seq {#2}{\seq_gput_right:Nn \g_tx_author_seq {#2}}
    \prop_gput:NnV \g_tx_author_name_prop {#2} \l_tmpa_tl
    \prop_gput:NnV \g_tx_author_color_prop {#2} \l_tmpb_tl
  }
\NewDocumentCommand \txdefineauthor { O{} m } {\tx_define_author:nn {#1}{#2}}
\NewDocumentCommand \txsetanonymousname { m } {\tl_gset:Nn \g_tx_anonymous_name_tl {#1}\prop_gput:Nnn \g_tx_author_name_prop {anonymous}{#1}}

\cs_new_protected:Npn \tx_change_reset:
  {
    \tl_set:Nn \l_tx_author_tl {anonymous}
    \tl_clear:N \l_tx_id_tl
    \tl_clear:N \l_tx_comment_tl
    \tl_set:Nn \l_tx_status_tl {pending}
    \tl_clear:N \l_tx_label_tl
    \bool_set_false:N \l_tx_legacy_label_bool
  }
\cs_new_protected:Npn \tx_change_parse:n #1
  {
    \tx_change_reset:
    \tl_if_blank:nF {#1}
      {
        \tl_if_in:nnTF {#1}{=}
          {\keys_set:nn {tx/change}{#1}}
          {\tl_set:Nn \l_tx_label_tl {#1}\bool_set_true:N \l_tx_legacy_label_bool}
      }
    \tx_change_validate:
  }
\cs_new_protected:Npn \tx_change_validate:
  {
    \bool_if:NF \l_tx_legacy_label_bool
      {
        \prop_if_in:NVF \g_tx_author_name_prop \l_tx_author_tl
          {\PackageError{texchanges}{Undefined~author~'\l_tx_author_tl'}{Define~it~with~\string\txdefineauthor.}}
        \tl_if_blank:VF \l_tx_id_tl
          {
            \prop_if_in:NVTF \g_tx_seen_id_prop \l_tx_id_tl
              {\PackageError{texchanges}{Duplicate~change~ID~'\l_tx_id_tl'}{Every~non-empty~change~ID~must~be~unique.}}
              {\prop_gput:NVn \g_tx_seen_id_prop \l_tx_id_tl {seen}}
          }
      }
    \str_if_eq:VnT \l_tx_status_tl {pending}{\bool_gset_true:N \g_tx_pending_bool}
  }

\cs_new:Npn \tx_author_name:
  {
    \bool_if:NTF \l_tx_legacy_label_bool {\l_tx_label_tl}
      {
        \str_if_eq:VnTF \g_tx_author_text_tl {name}
          {\prop_item:NV \g_tx_author_name_prop \l_tx_author_tl}
          {\str_if_eq:VnTF \l_tx_author_tl {anonymous}{}{\l_tx_author_tl}}
      }
  }
\cs_new_protected:Npn \tx_set_color:
  {
    \bool_if:NT \g_tx_color_bool
      {
        \bool_if:NTF \l_tx_legacy_label_bool
          {\colorlet{txCurrentColor}{texchangesComment}}
          {\prop_get:NVN \g_tx_author_color_prop \l_tx_author_tl \l_tx_color_tl\colorlet{txCurrentColor}{\l_tx_color_tl}}
      }
  }

% Localized public strings. Users may redefine these directly.
\cs_new:Npn \txlistchangesname {List~of~changes}
\cs_new:Npn \txsummaryname {Changes}
\cs_new:Npn \txcompactsummaryname {Changes~(compact)}
\cs_new:Npn \txauthorname {Author}
\cs_new:Npn \txaddedname {Added}
\cs_new:Npn \txremovedname {Removed}
\cs_new:Npn \txreplacedname {Replaced}
\cs_new:Npn \txhighlightedname {Highlighted}
\cs_new:Npn \txcommentedname {Commented}
\cs_new:Npn \txstatusname {Status}
\cs_new:Npn \txnochangesname {No~changes.}
\cs_new_protected:Npn \tx_localize:nnnnnnnnn #1#2#3#4#5#6#7#8#9
  {\cs_set:Npn \txlistchangesname {#1}\cs_set:Npn \txsummaryname {#2}\cs_set:Npn \txauthorname {#3}\cs_set:Npn \txaddedname {#4}\cs_set:Npn \txremovedname {#5}\cs_set:Npn \txreplacedname {#6}\cs_set:Npn \txhighlightedname {#7}\cs_set:Npn \txcommentedname {#8}\cs_set:Npn \txstatusname {#9}}
\cs_new_protected:Npn \tx_install_localizations:
  {
    \cs_if_exist:NT \addto
      {
        \cs_if_exist:NT \captionsenglish {\addto\captionsenglish{\tx_localize:nnnnnnnnn{List of changes}{Changes}{Author}{Added}{Removed}{Replaced}{Highlighted}{Commented}{Status}}}
        \cs_if_exist:NT \captionsbritish {\addto\captionsbritish{\tx_localize:nnnnnnnnn{List of changes}{Changes}{Author}{Added}{Removed}{Replaced}{Highlighted}{Commented}{Status}}}
        \cs_if_exist:NT \captionsgerman {\addto\captionsgerman{\tx_localize:nnnnnnnnn{Liste der Änderungen}{Änderungen}{Autor}{Eingefügt}{Gelöscht}{Ersetzt}{Hervorgehoben}{Kommentiert}{Status}}}
        \cs_if_exist:NT \captionsngerman {\addto\captionsngerman{\tx_localize:nnnnnnnnn{Liste der Änderungen}{Änderungen}{Autor}{Eingefügt}{Gelöscht}{Ersetzt}{Hervorgehoben}{Kommentiert}{Status}}}
        \cs_if_exist:NT \captionsfrench {\addto\captionsfrench{\tx_localize:nnnnnnnnn{Liste des modifications}{Modifications}{Auteur}{Ajouté}{Supprimé}{Remplacé}{Mis en évidence}{Commenté}{Statut}}}
        \cs_if_exist:NT \captionsitalian {\addto\captionsitalian{\tx_localize:nnnnnnnnn{Lista delle modifiche}{Modifiche}{Autore}{Aggiunto}{Rimosso}{Sostituito}{Evidenziato}{Commentato}{Stato}}}
        \cs_if_exist:NT \captionsvietnamese {\addto\captionsvietnamese{\tx_localize:nnnnnnnnn{Danh sách thay đổi}{Các thay đổi}{Tác giả}{Thêm}{Xóa}{Thay thế}{Đánh dấu}{Nhận xét}{Trạng thái}}}
      }
  }
\AtBeginDocument{\tx_install_localizations:}

% --------------------------------------------------------------------------
% Rendering hooks and styles
% --------------------------------------------------------------------------
\cs_new:Npn \tx_style:nn #1#2
  {
    \str_case:nnF {#1}
      {
        {colored}{#2}{sout}{\sout{#2}}{xout}{\xout{#2}}{uline}{\uline{#2}}
        {uuline}{\uuline{#2}}{uwave}{\uwave{#2}}{dashuline}{\dashuline{#2}}
        {dotuline}{\dotuline{#2}}{bf}{\textbf{#2}}{it}{\textit{#2}}
        {sl}{\textsl{#2}}{em}{\emph{#2}}
      }{#2}
  }
\cs_new:Npn \tx_added_markup:n #1 {\tx_style:Vn \g_tx_added_style_tl {#1}}
\cs_new:Npn \tx_deleted_markup:n #1 {\tx_style:Vn \g_tx_deleted_style_tl {#1}}
\cs_new:Npn \tx_highlight_markup:n #1
  {\str_if_eq:VnTF \g_tx_highlight_style_tl {background}{\hl{#1}}{\tx_style:Vn \g_tx_highlight_style_tl {#1}}}
\cs_generate_variant:Nn \tx_style:nn {Vn}

\cs_new:Npn \tx_author_markup:n #1
  {
    \str_case:VnF \g_tx_author_style_tl
      {{superscript}{\textsuperscript{#1}}{subscript}{\textsubscript{#1}}{brackets}{(#1)}{footnote}{\footnote{#1}}{none}{}}
      {\textsuperscript{#1}}
  }
\cs_new_protected:Npn \tx_author_at:n #1
  {\str_if_eq:VnT \g_tx_author_position_tl {#1}{\tl_if_blank:eF {\tx_author_name:}{{\color{txCurrentColor}\tx_author_markup:n{\tx_author_name:}}}}}
\cs_new_protected:Npn \tx_comment_markup:n #1
  {
    \str_case:VnF \g_tx_comment_style_tl
      {
        {inline}{{\color{texchangesComment}\textbf{[\tx_author_name:\space}#1\textbf{]}}}
        {margin}{\marginpar{{\color{txCurrentColor}\textbf{[\tx_author_name:]}~#1}}}
        {footnote}{\footnote{\textbf{[\tx_author_name:]}~#1}}
        {uwave}{{\color{txCurrentColor}\uwave{\textbf{[\tx_author_name:]}~#1}}}
        {todo}{\bool_if:NTF \g_tx_todonotes_loaded_bool {\todo[color=txCurrentColor!10,bordercolor=txCurrentColor,nolist]{#1}}{{\color{texchangesComment}[#1]}}}
      }{{\color{texchangesComment}[#1]}}
  }
\NewDocumentCommand \txsetaddedmarkup { m } {\cs_gset:Npn \tx_added_markup:n ##1 {#1}}
\NewDocumentCommand \txsetdeletedmarkup { m } {\cs_gset:Npn \tx_deleted_markup:n ##1 {#1}}
\NewDocumentCommand \txsethighlightmarkup { m } {\cs_gset:Npn \tx_highlight_markup:n ##1 {#1}}
\NewDocumentCommand \txsetcommentmarkup { m } {\cs_gset_protected:Npn \tx_comment_markup:n ##1 {#1}}
\NewDocumentCommand \txsetauthormarkup { m } {\cs_gset:Npn \tx_author_markup:n ##1 {#1}}
\NewDocumentCommand \txsetauthormarkupposition { m } {\tl_gset:Nn \g_tx_author_position_tl {#1}}
\NewDocumentCommand \txsetauthormarkuptext { m } {\tl_gset:Nn \g_tx_author_text_tl {#1}}
\NewDocumentCommand \txsettruncatewidth { m } {\dim_gset:Nn \g_tx_truncate_width_dim {#1}}
\NewDocumentCommand \txsetsummarywidth { m } {\dim_gset:Nn \g_tx_summary_width_dim {#1}}
\NewDocumentCommand \txsetsummarytowidth { m } {\hbox_set:Nn \l_tmpa_box {#1}\dim_gset:Nn \g_tx_summary_width_dim {\box_wd:N \l_tmpa_box}}
\NewDocumentCommand \txsetlocextension { m } {\tl_gset:Nn \g_tx_loc_ext_tl {#1}}
\NewDocumentCommand \txsetsocextension { m } {\tl_gset:Nn \g_tx_soc_ext_tl {#1}}

% --------------------------------------------------------------------------
% Change output, counters, and auxiliary report data
% --------------------------------------------------------------------------
\iow_new:N \g_tx_report_iow
\cs_generate_variant:Nn \iow_open:Nn {Nx}
\cs_new_protected:Npn \tx_count:n #1
  {
    \tl_set:Nx \l_tmpa_tl {\l_tx_author_tl/#1/\l_tx_status_tl}
    \prop_get:NVNTF \g_tx_counts_prop \l_tmpa_tl \l_tmpb_tl
      {\prop_gput:NVx \g_tx_counts_prop \l_tmpa_tl {\int_eval:n{\l_tmpb_tl+1}}}
      {\prop_gput:NVn \g_tx_counts_prop \l_tmpa_tl {1}}
  }
\cs_new_protected:Npn \tx_record:nn #1#2
  {
    \str_if_eq:VnT \g_tx_mode_tl {review}
      {
        \tx_count:n {#1}
        \phantomsection
        \tl_if_blank:VF \l_tx_id_tl {\label{tx:\l_tx_id_tl}}
        \exp_args:NV \addtocontents \g_tx_loc_ext_tl
          {\protect\txreportline{#1}{\l_tx_status_tl}{\l_tx_author_tl}{\l_tx_id_tl}{#2}}
      }
  }
\cs_new_protected:Npn \tx_change_begin:nnn #1#2#3
  {
    \tx_change_parse:n {#2}
    \tl_set:Nn \l_tx_type_tl {#1}
    \tl_set:Nn \l_tx_excerpt_tl {#3}
    \tx_set_color:
  }
\cs_new_protected:Npn \tx_pending_markup:nn #1#2
  {
    \tx_author_at:n {left}
    \str_case:Vn \l_tx_type_tl
      {
        {added}{{\bool_if:NT \g_tx_color_bool{\color{txCurrentColor}}\tx_added_markup:n{#2}}}
        {removed}{{\bool_if:NT \g_tx_color_bool{\color{txCurrentColor}}\tx_deleted_markup:n{#1}}}
        {replaced}{{\bool_if:NT \g_tx_color_bool{\color{texchangesRemoved}}\tx_deleted_markup:n{#1}}\allowbreak\hspace{.25em}{\bool_if:NT \g_tx_color_bool{\color{texchangesAdded}}\tx_added_markup:n{#2}}}
        {highlighted}{{\bool_if:NT \g_tx_color_bool{\sethlcolor{txCurrentColor!25}}\tx_highlight_markup:n{#2}}}
        {commented}{\tx_comment_markup:n{#2}}
      }
    \tx_author_at:n {right}
    \tl_if_blank:VF \l_tx_comment_tl {\tx_comment_markup:n{\l_tx_comment_tl}}
  }
\cs_new_protected:Npn \tx_render:nn #1#2
  {
    \str_case:Vn \g_tx_mode_tl
      {
        {original}{\str_case:Vn \l_tx_type_tl {{removed}{#1}{replaced}{#1}{highlighted}{#2}}}
        {final}{\str_if_eq:VnTF \l_tx_status_tl {rejected}{\str_case:Vn \l_tx_type_tl {{removed}{#1}{replaced}{#1}{highlighted}{#2}}}{\str_case:Vn \l_tx_type_tl {{added}{#2}{replaced}{#2}{highlighted}{#2}}}}
        {review}{\str_if_eq:VnTF \l_tx_status_tl {pending}{\tx_pending_markup:nn{#1}{#2}}{\str_if_eq:VnTF \l_tx_status_tl {accepted}{\str_case:Vn \l_tx_type_tl {{added}{#2}{replaced}{#2}{highlighted}{#2}}}{\str_case:Vn \l_tx_type_tl {{removed}{#1}{replaced}{#1}{highlighted}{#2}}}}}
      }
  }
\cs_new_protected:Npn \tx_change:nnnn #1#2#3#4
  {\group_begin:\tx_change_begin:nnn{#1}{#2}{#4}\tx_record:nn{#1}{#4}\tx_render:nn{#3}{#4}\group_end:}
\cs_new_protected:Npn \tx_compat_change:nnnn #1#2#3#4
  {
    \group_begin:
    \tx_change_reset:
    \keys_set:nn {tx/compat-change}{#2}
    \tx_change_validate:
    \tl_set:Nn \l_tx_type_tl {#1}
    \tl_set:Nn \l_tx_excerpt_tl {#4}
    \tx_set_color:
    \tx_record:nn{#1}{#4}
    \tx_render:nn{#3}{#4}
    \group_end:
  }

\NewDocumentCommand \txadd { O{} m } {\tx_change:nnnn{added}{#1}{}{#2}}
\NewDocumentCommand \txremove { O{} m } {\tx_change:nnnn{removed}{#1}{#2}{#2}}
\NewDocumentCommand \txreplace { O{} m m } {\tx_change:nnnn{replaced}{#1}{#2}{#3}}
\NewDocumentCommand \txhighlight { O{} m } {\tx_change:nnnn{highlighted}{#1}{#2}{#2}}
\NewDocumentCommand \txcomment { O{} m } {\tx_change:nnnn{commented}{#1}{}{#2}}

% --------------------------------------------------------------------------
% List and summary of changes
% --------------------------------------------------------------------------
\tl_new:N \l_tx_list_style_tl
\tl_new:N \l_tx_list_title_tl
\clist_new:N \l_tx_list_show_clist
\clist_new:N \l_tx_list_status_clist
\clist_new:N \l_tx_list_author_clist
\keys_define:nn {tx/list}
  {
    style .choices:nn = {list,summary,compactsummary}{\tl_set:Nx \l_tx_list_style_tl {\l_keys_choice_tl}},
    title .tl_set:N = \l_tx_list_title_tl,
    show .clist_set:N = \l_tx_list_show_clist,
    status .clist_set:N = \l_tx_list_status_clist,
    author .clist_set:N = \l_tx_list_author_clist
  }
\cs_new:Npn \txreportline #1#2#3#4#5
  {
    \clist_if_in:NnT \l_tx_list_show_clist {#1}
      {\clist_if_in:NnT \l_tx_list_status_clist {#2}
        {\clist_if_in:NnT \l_tx_list_author_clist {#3}
          {\par\noindent\textbf{\tx_type_name:n{#1}}\tl_if_blank:nF{#4}{~(#4)}:~\truncate{\g_tx_truncate_width_dim}{#5}\tl_if_blank:nF{#4}{\dotfill\pageref{tx:#4}}\par}}}
  }
\cs_new:Npn \tx_type_name:n #1 {\str_case:nnF{#1}{{added}{\txaddedname}{removed}{\txremovedname}{replaced}{\txreplacedname}{highlighted}{\txhighlightedname}{commented}{\txcommentedname}}{#1}}
\cs_new_protected:Npn \tx_summary:
  {
    \prop_set_eq:NN \l_tx_report_counts_prop \g_tx_counts_prop
    \exp_args:Nx \file_if_exist:nT {\jobname.\g_tx_soc_ext_tl}
      {
        \prop_clear:N \l_tx_report_counts_prop
        \exp_args:Nx \file_input:n {\jobname.\g_tx_soc_ext_tl}
      }
    \seq_map_inline:Nn \g_tx_author_seq
      {
        \par\noindent\textbf{{\txauthorname}:~\prop_item:Nn \g_tx_author_name_prop{##1}}\\
        \clist_map_inline:nn {added,removed,replaced,highlighted,commented}
          {\int_zero:N \l_tmpa_int\clist_map_inline:Nn \l_tx_list_status_clist {\prop_get:NnNT \l_tx_report_counts_prop {##1/####1/########1}\l_tmpa_tl{\int_add:Nn \l_tmpa_int{\l_tmpa_tl}}}\str_if_eq:VnTF \l_tx_list_style_tl{compactsummary}{\int_compare:nNnT{\l_tmpa_int}>{0}{\tx_type_name:n{####1}:~\int_use:N\l_tmpa_int\quad}}{\tx_type_name:n{####1}:~\int_use:N\l_tmpa_int\quad}}\par
        \clist_map_inline:Nn \l_tx_list_status_clist
          {\int_zero:N \l_tmpa_int\clist_map_inline:nn {added,removed,replaced,highlighted,commented}{\prop_get:NnNT \l_tx_report_counts_prop {##1/########1/####1}\l_tmpa_tl{\int_add:Nn \l_tmpa_int{\l_tmpa_tl}}}\textit{####1}:~\int_use:N\l_tmpa_int\quad}\par
      }
  }
\cs_new_protected:Npn \txsummaryentry #1#2
  {\prop_put:Nnn \l_tx_report_counts_prop {#1}{#2}}
\cs_new_protected:Npn \tx_write_summary_aux:
  {
    \iow_open:Nx \g_tx_report_iow {\jobname.\g_tx_soc_ext_tl}
    \prop_map_inline:Nn \g_tx_counts_prop
      {\iow_now:Nx \g_tx_report_iow {\exp_not:N \txsummaryentry {\exp_not:n {##1}} {##2}}}
    \iow_close:N \g_tx_report_iow
  }
\NewDocumentCommand \txlistofchanges { O{} }
  {
    \str_if_eq:VnT \g_tx_mode_tl {review}
      {
        \tl_set:Nn \l_tx_list_style_tl {list}\tl_clear:N \l_tx_list_title_tl
        \clist_set:Nn \l_tx_list_show_clist {added,removed,replaced,highlighted,commented}
        \clist_set:Nn \l_tx_list_status_clist {pending,accepted,rejected}
        \clist_set:Nx \l_tx_list_author_clist {\seq_use:Nn \g_tx_author_seq {,}}
        \keys_set:nn {tx/list}{#1}
        \section*{\tl_if_blank:VTF \l_tx_list_title_tl{\str_if_eq:VnTF \l_tx_list_style_tl{list}{\txlistchangesname}{\txsummaryname}}{\l_tx_list_title_tl}}
        \str_if_eq:VnTF \l_tx_list_style_tl {list}
          {
            \exp_args:Nx \file_if_exist:nF {\jobname.\g_tx_loc_ext_tl}
              {\emph{\txnochangesname}}
            \exp_args:NV \@starttoc \g_tx_loc_ext_tl
          }
          {\tx_summary:}
      }
  }
\AtEndDocument
  {
    \str_if_eq:VnT \g_tx_mode_tl {review}
      {\tx_write_summary_aux:}
    \str_if_eq:VnT \g_tx_mode_tl {final}
      {\bool_if:NT \g_tx_pending_bool{\PackageWarningNoLine{texchanges}{Pending~changes~were~accepted~by~final~mode}}}
  }

% --------------------------------------------------------------------------
% Native aliases and opt-in changes compatibility
% --------------------------------------------------------------------------
\cs_if_exist:NF \add {\cs_new_eq:NN \add \txadd}
\cs_if_exist:NF \remove {\cs_new_eq:NN \remove \txremove}
\cs_if_exist:NF \replace {\cs_new_eq:NN \replace \txreplace}
\str_if_eq:VnF \g_tx_compat_tl {changes}
  {
    \cs_if_exist:NF \highlight {\cs_new_eq:NN \highlight \txhighlight}
    \cs_if_exist:NF \comment {\cs_new_eq:NN \comment \txcomment}
  }

\cs_new_protected:Npn \tx_compat_define:NN #1#2
  {
    \str_case:Vn \g_tx_prefix_strategy_tl
      {
        {always}{\cs_new_eq:cN {ch\cs_to_str:N #1} #2}
        {ifneeded}{\cs_if_exist:NTF #1 {\cs_new_eq:cN {ch\cs_to_str:N #1} #2}{\cs_new_eq:NN #1 #2}}
        {none}{\cs_if_exist:NTF #1 {\PackageError{texchanges}{Command~\token_to_str:N#1~already~defined}{Use~commandnameprefix=ifneeded~or~always.}}{\cs_new_eq:NN #1 #2}}
      }
  }
\NewDocumentCommand \txcompatadded { O{} m } {\tx_compat_change:nnnn{added}{#1}{}{#2}}
\NewDocumentCommand \txcompatdeleted { O{} m } {\tx_compat_change:nnnn{removed}{#1}{#2}{#2}}
\NewDocumentCommand \txcompatreplaced { O{} m m } {\tx_compat_change:nnnn{replaced}{#1}{#3}{#2}}
\NewDocumentCommand \txcompathighlight { O{} m } {\tx_compat_change:nnnn{highlighted}{#1}{#2}{#2}}
\NewDocumentCommand \txcompatcomment { O{} m } {\tx_compat_change:nnnn{commented}{#1}{}{#2}}

\str_if_eq:VnT \g_tx_compat_tl {changes}
  {
    \tx_compat_define:NN \added \txcompatadded
    \tx_compat_define:NN \deleted \txcompatdeleted
    \tx_compat_define:NN \replaced \txcompatreplaced
    \tx_compat_define:NN \highlight \txcompathighlight
    \tx_compat_define:NN \comment \txcompatcomment
    \cs_new_eq:NN \definechangesauthor \txdefineauthor
    \cs_new_eq:NN \listofchanges \txlistofchanges
    \cs_new_eq:NN \setaddedmarkup \txsetaddedmarkup
    \cs_new_eq:NN \setdeletedmarkup \txsetdeletedmarkup
    \cs_new_eq:NN \sethighlightmarkup \txsethighlightmarkup
    \cs_new_eq:NN \setcommentmarkup \txsetcommentmarkup
    \cs_new_eq:NN \setauthormarkup \txsetauthormarkup
    \cs_new_eq:NN \setauthormarkupposition \txsetauthormarkupposition
    \cs_new_eq:NN \setauthormarkuptext \txsetauthormarkuptext
    \cs_new_eq:NN \setanonymousname \txsetanonymousname
    \cs_new_eq:NN \settruncatewidth \txsettruncatewidth
    \cs_new_eq:NN \setsummarywidth \txsetsummarywidth
    \cs_new_eq:NN \setsummarytowidth \txsetsummarytowidth
    \cs_new_eq:NN \setlocextension \txsetlocextension
    \cs_new_eq:NN \setsocextension \txsetsocextension
  }

\cs_new:Npn \texchangesmode {\g_tx_mode_tl}
\PackageInfo{texchanges}{Rendering~changes~in~\g_tx_mode_tl~mode}
\ExplSyntaxOff
\endinput