/*  Part of ClioPatria SeRQL and SPARQL server

    Author:        Jan Wielemaker
    E-mail:        J.Wielemaker@vu.nl
    WWW:           http://www.swi-prolog.org
    Copyright (c)  2010-2018, University of Amsterdam,
                              VU University Amsterdam
    All rights reserved.

    Redistribution and use in source and binary forms, with or without
    modification, are permitted provided that the following conditions
    are met:

    1. Redistributions of source code must retain the above copyright
       notice, this list of conditions and the following disclaimer.

    2. Redistributions in binary form must reproduce the above copyright
       notice, this list of conditions and the following disclaimer in
       the documentation and/or other materials provided with the
       distribution.

    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
    FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
    COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
    INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
    BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
    LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
    CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
    LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
    ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
    POSSIBILITY OF SUCH DAMAGE.
*/

:- module(setup,
          [ setup_scripts/2,            % +SrcDir, +DestDir
            setup_default_config/3,     % +SrcDir, +DestDir, +Options
            setup_prolog_executable/1,  % -Exec for #!
            setup_goodbye/0,
            copy_file_with_vars/3       % +In, +Out, +Vars
          ]).
:- use_module(library(apply)).
:- use_module(library(filesex)).
:- use_module(library(option)).
:- use_module(library(lists)).
:- use_module(library(conf_d)).
:- use_module(library(apply_macros), []).


/** <module> Configuration (setup) of ClioPatria
*/

:- multifile
    substitutions/1.

%!  setup_scripts(+SrcDir, +DstDir)
%
%   Copy all *.in files in SrcDir   into DstDir, replacing variables
%   denoted as @NAME@. Defined variables are:
%
%       $ SWIPL :
%       The SWI-Prolog executable as it must be used in #!
%       $ CLIOPATRIA :
%       Directory that holds the ClioPatria system
%       $ CWD :
%       The (current) installation directory
%       $ PARENTDIR :
%       Parent of CWD.  This can be useful if the startup-script
%       is located in a subdirectory of a project.

setup_scripts(SrcDir, DstDir) :-
    substitutions(Vars),
    print_message(informational, setup(localize_dir(SrcDir))),
    atom_concat(SrcDir, '/*.in', Pattern),
    expand_file_name(Pattern, Files),
    maplist(install_file(Vars, DstDir), Files).

install_file(Vars, Dest, InFile) :-
    (   exists_directory(Dest)
    ->  file_name_extension(File, in, InFile),
        file_base_name(File, Base0),
        rename_script(Base0, Base),
        directory_file_path(Dest, Base, DstFile)
    ;   DstFile = Dest
    ),
    copy_file_with_vars(InFile, DstFile, Vars),
    make_runnable(DstFile),
    print_message(informational, setup(install_file(DstFile))).

%!  rename_script(+ScriptIn, -Script)
%
%   Rename scripts to satisfy the target file name association.

rename_script(Run, Script) :-
    current_prolog_flag(associate, Ext),
    file_name_extension(run, _, Run),
    file_name_extension(run, Ext, Script),
    !.
rename_script(Script, Script).

%!  make_runnable(+File)
%
%   Make a file executable if it starts with #!

make_runnable(File) :-
    setup_call_cleanup(
        open(File, read, In),
        read_line_to_codes(In, Line),
        close(In)),
    phrase("#!", Line, _),
    !,
    '$mark_executable'(File).
make_runnable(_).


%!  setup_prolog_executable(?Var, ?Value)
%
%   Executable to put in #!Path. On Windows   this  is bogus, but it
%   may not contain spaces,  so  we   include  the  default Unix RPM
%   location.

setup_prolog_executable(PL) :-
    catch(getenv('SWIPL', PL), _, fail),
    !.
setup_prolog_executable('/usr/bin/swipl') :-
    current_prolog_flag(windows, true),
    !.
setup_prolog_executable(PL) :-
    current_prolog_flag(executable, Exe),
    file_base_name(Exe, Base),
    (   which(Base, PL)
    ->  true
    ;   PL = Exe
    ).

which(File, Path) :-
    catch(getenv('PATH', SearchPath), _, fail),
    atomic_list_concat(Parts, :, SearchPath),
    member(Dir, Parts),
    directory_file_path(Dir, File, Path),
    access_file(Path, execute).

%!  setup_default_config(+ConfigEnabled, +ConfigAvail, +Options)
%
%   Setup  the  enabled  cofiguration  directory    from  the  given
%   ConfigAvail. If Options include help(true), this prints a set of
%   available options.

setup_default_config(ConfigEnabled, ConfigAvail, Options) :-
    option(help(true), Options),
    !,
    setup_config_help(ConfigEnabled, ConfigAvail).
setup_default_config(ConfigEnabled, ConfigAvail, Options) :-
    setup_config_enabled(ConfigEnabled, Options),
    default_config(ConfigEnabled, ConfigAvail, Options).


setup_config_enabled(ConfigEnabled, Options) :-
    (   exists_directory(ConfigEnabled)
    ->  true
    ;   make_directory(ConfigEnabled)
    ),
    directory_file_path(ConfigEnabled, 'README.txt', Readme),
    (   exists_file(Readme)
    ->  true
    ;   option(readme(ReadMeIn), Options)
    ->  print_message(informational,
                      setup(install_file('README.txt', ConfigEnabled))),
        substitutions(Vars),
        install_file(Vars, Readme, ReadMeIn)
    ).

%!  default_config(+ConfigEnabledDir, +ConfigAvailDir, +Options)
%
%   Install a default configuration in ConfigEnabledDir based on the
%   information from ConfigAvailDir.  Options:
%
%     * without(Base)
%     Skip this file from the installation
%     * with(Base)
%     Add this file to the installation

default_config(ConfigEnabled, ConfigAvail, Options) :-
    directory_file_path(ConfigEnabled, 'config.done', DoneFile),
    (   exists_file(DoneFile)
    ->  read_file_to_terms(DoneFile, Installed, [])
    ;   Installed = []
    ),
    include(with, Options, Requests),
    maplist(with_file(ConfigAvail), Requests, With),
    config_defaults(ConfigAvail, Defaults0),
    exclude(without(Options), Defaults0, Defaults),
    append(Defaults, With, Install),
    (   Install \== []
    ->  setup_call_cleanup(open_done(DoneFile, Out),
                           maplist(install_config(Installed,
                                                  ConfigEnabled,
                                                  ConfigAvail,
                                                  Out, Options),
                                   Install),
                           close(Out))
    ;   true
    ).

without(Options, file(Key,_,_)) :-
    memberchk(without(Key), Options).

with(with(_)).

with_file(ConfigAvail, with(Key), file(Key, Path, link)) :-
    directory_file_path(ConfigAvail, Key, FileBase),
    absolute_file_name(FileBase, Path,
                       [ access(read),
                         file_type(prolog)
                       ]).

open_done(DoneFile, Out) :-
    exists_file(DoneFile),
    !,
    open(DoneFile, append, Out).
open_done(DoneFile, Out) :-
    open(DoneFile, write, Out),
    format(Out, '/* Generated file~n', []),
    format(Out, '   Keep track of installed config files~n', []),
    format(Out, '*/~n~n', []).

install_config(Installed, ConfigEnabled, ConfigAvail, Out, Options,
               file(_Key, File, How0)) :-
    file_base_name(File, Base),
    \+ ( memberchk(file(IFile,_,_), Installed),
         file_base_name(IFile, Base)
       ),
    !,
    final_how(How0, How, Options),
    install_config_file(How, ConfigEnabled, File),
    get_time(Now),
    Stamp is round(Now),
    format(Out, '~q.~n', [file(Base, ConfigAvail, Stamp)]).
install_config(_, _, _, _, _, _).

final_how(link, How, Options) :-
    !,
    (   option(link(true), Options)
    ->  How = link
    ;   How = include
    ).
final_how(How, How, _).


%!  config_defaults(+ConfigAvail, -Defaults) is det.
%
%   Defaults is a list of file(Key, File, How) that indicates which
%   available config files must be installed by default.
%
%   @param ConfigAvail is either a directory or an alias.

config_defaults(ConfigAvail, Defaults) :-
    compound(ConfigAvail),
    !,
    findall(Defs,
            (   absolute_file_name(ConfigAvail, Dir,
                                   [ file_type(directory),
                                     solutions(all),
                                     access(read)
                                   ]),
                config_defaults_dir(Dir, Defs)
            ),
            AllDefs),
    append(AllDefs, Defaults).
config_defaults(ConfigAvail, Defaults) :-
    config_defaults_dir(ConfigAvail, Defaults).


config_defaults_dir(ConfigAvail, Defaults) :-
    directory_file_path(ConfigAvail, 'DEFAULTS', DefFile),
    access_file(DefFile, read),
    !,
    read_file_to_terms(DefFile, Terms, []),
    config_defaults(Terms, ConfigAvail, Defaults).
config_defaults_dir(_, []).

config_defaults([], _, []).
config_defaults([H|T0], ConfigAvail, [F|T]) :-
    config_default(H, ConfigAvail, F),
    !,
    config_defaults(T0, ConfigAvail, T).
config_defaults([_|T0], ConfigAvail, T) :-
    config_defaults(T0, ConfigAvail, T).


config_default((Head :- Body), ConfigAvail, File) :-
    !,
    call(Body),
    config_default(Head, ConfigAvail, File).
config_default(config(FileBase, How), ConfigAvail,
               file(Key, Path, How)) :-
    !,
    (   File = FileBase
    ;   prolog_file_type(Ext, prolog),
        file_name_extension(FileBase, Ext, File)
    ),
    directory_file_path(ConfigAvail, File, Path),
    exists_file(Path),
    file_base_name(File, Base),
    file_name_extension(Key, _, Base).
config_default(Term, _, _) :-
    domain_error(config_term, Term).


%!  setup_config_help(+ConfigEnabled, +ConfigAvail) is det.

setup_config_help(ConfigEnabled, ConfigAvail) :-
    doc_collect(true),
    config_defaults(ConfigAvail, Defaults),
    conf_d_configuration(ConfigAvail, ConfigEnabled, Configs),
    partition(default_config(Defaults), Configs, Default, NonDefault),
    maplist(config_help(without), Default, Without),
    maplist(config_help(with), NonDefault, With),
    print_message(informational, setup(general)),
    print_message(informational, setup(without(Without))),
    print_message(informational, setup(with(With))),
    print_message(informational, setup(advice)).

default_config(Defaults, Key-_) :-
    memberchk(file(Key,_,_), Defaults).

config_help(With, Key-[Example,_], Help) :-
    (   conf_d_member_data(title, Example, Title)
    ->  true
    ;   Title = 'no description'
    ),
    Help =.. [With,Key,Title].


%!  install_config_file(+How, +ConfDir, +File) is det.
%
%   Install  the  configuration  file  File   in  the  configuration
%   directory ConfDir. How dictates how the file is installed and is
%   one of:
%
%     * link
%     Link the file. This means that the configured system updates
%     the config file if it is updated in the package.
%     * include
%     As `link`, but avoiding the nead for symlinks
%     * copy
%     Copy the file.  This is used if the config file in the package
%     is merely a skeleton that needs to be instantiated for the
%     specific ClioPatria installation.

install_config_file(_, ConfDir, Path) :-
    file_base_name(Path, File),
    directory_file_path(ConfDir, File, Dest),
    exists_file(Dest),
    !.
install_config_file(link, ConfDir, Source) :-
    file_base_name(Source, File),
    directory_file_path(ConfDir, File, Dest),
    print_message(informational, setup(install_file(File))),
    link_prolog_file(Source, Dest).
install_config_file(include, ConfDir, Source) :-
    file_base_name(Source, File),
    directory_file_path(ConfDir, File, Dest),
    print_message(informational, setup(install_file(File))),
    include_prolog_file(Source, Dest).
install_config_file(copy, ConfDir, Source) :-
    file_base_name(Source, File),
    directory_file_path(ConfDir, File, Dest),
    print_message(informational, setup(install_file(File))),
    copy_file(Source, Dest).

%!  link_prolog_file(+SourcePath, +DestDir) is det.
%
%   Install a skeleton file by linking it.  If it is not possible to
%   create a symbolic link (typically on  system that do not support
%   proper links such as Windows), create  a Prolog `link' file that
%   loads the target.

link_prolog_file(Source, Dest) :-
    relative_file_name(Source, Dest, Rel),
    catch(link_file(Rel, Dest, symbolic), Error, true),
    (   var(Error)
    ->  true
    ;   include_prolog_file(Source, Dest)
    ->  true
    ;   throw(Error)
    ).

%!  include_prolog_file(+Source, +Dest) is det.
%
%   Creat a _|link file|_ for a Prolog file. Make sure to delete the
%   target first, to avoid an accidental   write  through a symbolic
%   link.

include_prolog_file(Source, Dest) :-
    (   access_file(Dest, exist)
    ->  delete_file(Dest)
    ;   true
    ),
    file_base_name(Source, File),
    file_name_extension(Base, pl, File),
    atomic_list_concat([link_, Base, '_conf'], LinkModule),
    setup_call_cleanup(
        open(Dest, write, Out),
        ( format(Out, '/* Linked config file */~n', []),
          format(Out, ':- module(~q, []).~n', [LinkModule]),
          format(Out, ':- ~q.~n', [reexport(config_available(Base))])
        ),
        close(Out)).

%!  setup_goodbye
%
%   Say we are done.  Waits for the user in Windows to allow the
%   user read messages.

setup_goodbye :-
    current_prolog_flag(windows, true),
    !,
    format(user_error, '~N~nReady.  Press any key to exit. ', []),
    get_single_char(_),
    format(' Goodbye!~n'),
    halt.
setup_goodbye :-
    halt.


                 /*******************************
                 *             UTIL             *
                 *******************************/

%!  copy_file_with_vars(+File, +DirOrFile, +Bindings) is det.
%
%   As =|cp File DirOrFile|=, while substituting =|@var@|=
%   from Bindings using copy_stream_with_vars/3.

copy_file_with_vars(File, DirOrFile, Bindings) :-
    destination_file(DirOrFile, File, Dest),
    open(File, read, In),
    open(Dest, write, Out),
    call_cleanup(copy_stream_with_vars(In, Out, Bindings),
                 (close(In), close(Out))).

destination_file(Dir, File, Dest) :-
    exists_directory(Dir),
    !,
    atomic_list_concat([Dir, File], /, Dest).
destination_file(Dest, _, Dest).


%!  copy_stream_with_vars(+In:stream, +Out:stream,
%!                        +Bindings:list(Var=Name)) is det.
%
%   Copy all data from In to Out,   while replacing =|@var@|= with a
%   binding from Bindings. In addition, =|!var!|= is replaced with a
%   Prolog-quoted version of the variable content.
%
%   @param Bindings List of Var=Name or Var(Name).  If exact case
%   match fails, the match is retried with the lowercase name.

copy_stream_with_vars(In, Out, []) :-
    !,
    copy_stream_data(In, Out).
copy_stream_with_vars(In, Out, Bindings) :-
    get_code(In, C0),
    copy_with_vars(C0, In, Out, Bindings).

copy_with_vars(-1, _, _, _) :- !.
copy_with_vars(0'@, In, Out, Bindings) :-
    !,
    insert_var(0'@, C2, In, Out, Bindings),
    copy_with_vars(C2, In, Out, Bindings).
copy_with_vars(0'!, In, Out, Bindings) :-
    !,
    insert_var(0'!, C2, In, Out, Bindings),
    copy_with_vars(C2, In, Out, Bindings).
copy_with_vars(C0, In, Out, Bindings) :-
    put_code(Out, C0),
    get_code(In, C1),
    copy_with_vars(C1, In, Out, Bindings).

insert_var(Mark, C2, In, Out, Bindings) :-
    get_code(In, C0),
    read_var_name(C0, In, VarNameS, C1),
    atom_codes(VarName, VarNameS),
    (   C1 == Mark,
        var_value(VarName, Value, Bindings)
    ->  (   Mark == 0'@
        ->  format(Out, '~w', [Value])
        ;   format(Out, '~q', [Value])
        ),
        get_code(In, C2)
    ;   format(Out, '~c~w', [Mark, VarName]),
        C2 = C1
    ).

read_var_name(C0, In, [C0|T], End) :-
    code_type(C0, alpha),
    !,
    get_code(In, C1),
    read_var_name(C1, In, T, End).
read_var_name(C0, _In, [], C0).

var_value(Name, Value, Vars) :-
    memberchk(Name=Value, Vars),
    !.
var_value(Name, Value, Vars) :-
    Term =.. [Name,Value],
    memberchk(Term, Vars),
    !.
var_value(Name, Value, Vars) :-
    downcase_atom(Name, Lwr),
    Lwr \== Name,
    var_value(Lwr, Value, Vars).


                 /*******************************
                 *            MESSAGES          *
                 *******************************/

:- multifile
    prolog:message//1.

prolog:message(setup(Term)) -->
    message(Term).

message(localize_dir(SrcDir)) -->
    [ 'Localizing scripts from ~p ...'-[SrcDir] ].
message(install_file(File, Dir)) -->
    [ 'Installing ~w in ~w ...'-[File, Dir] ].
message(install_file(File)) -->
    { file_base_name(File, Base) },
    [ ' Installing ~w ...'-[Base] ].
message(without(List)) -->
    [ nl, 'Use --without-X to disable default components' ],
    help(List).
message(with(List)) -->
    [ nl, 'Use --with-X to enable non-default components' ],
    help(List).
message(general) -->
    [ 'ClioPatria setup program', nl, nl,
      'General options', nl,
      '  --link~t~28|Use symbolic links in config-enabled'-[]
    ].
message(advice) -->
    [ nl, 'Typical setup for local interactive usage', nl,
      '  --with-debug --with-localhost'-[]
    ].

help([]) --> [].
help([H|T]) -->
    [nl],
    help(H),
    help(T).
help(without(Key, Title)) -->
    [ '  --without-~w~t~28|~w'-[Key, Title] ].
help(with(Key, Title)) -->
    [ '  --with-~w~t~28|~w'-[Key, Title] ].