package LatexIndent::Command;

#	This program is free software: you can redistribute it and/or modify
#	it under the terms of the GNU General Public License as published by
#	the Free Software Foundation, either version 3 of the License, or
#	(at your option) any later version.
#
#	This program is distributed in the hope that it will be useful,
#	but WITHOUT ANY WARRANTY; without even the implied warranty of
#	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#	GNU General Public License for more details.
#
#	See http://www.gnu.org/licenses/.
#
#	Chris Hughes, 2017
#
#	For all communication, please visit: https://github.com/cmhughes/latexindent.pl
use strict;
use warnings;
use LatexIndent::Tokens           qw/%tokens/;
use LatexIndent::TrailingComments qw/$trailingCommentRegExp/;
use LatexIndent::Switches         qw/$is_t_switch_active $is_tt_switch_active/;
use LatexIndent::GetYamlSettings  qw/%mainSettings/;
use LatexIndent::LogFile          qw/$logger/;
use Data::Dumper;
use Exporter qw/import/;
our @ISA = "LatexIndent::Document";    # class inheritance, Programming Perl, pg 321
our @EXPORT_OK
    = qw/construct_command_regexp $commandRegExp $commandRegExpTrailingComment $optAndMandAndRoundBracketsRegExpLineBreaks/;
our $commandCounter;
our $commandRegExp;
our $commandRegExpTrailingComment;
our $optAndMandAndRoundBracketsRegExp;
our $optAndMandAndRoundBracketsRegExpLineBreaks;

# store the regular expression for matching and replacing
sub construct_command_regexp {
    my $self = shift;

    $optAndMandAndRoundBracketsRegExp = $self->get_arguments_regexp(
        roundBrackets          => ${ $mainSettings{commandCodeBlocks} }{roundParenthesesAllowed},
        stringBetweenArguments => 1
    );

    $optAndMandAndRoundBracketsRegExpLineBreaks = $self->get_arguments_regexp(
        roundBrackets          => ${ $mainSettings{commandCodeBlocks} }{roundParenthesesAllowed},
        mode                   => "lineBreaksAtEnd",
        stringBetweenArguments => 1
    );

    # put together a list of the special command names (this was mostly motivated by the \@ifnextchar[ issue)
    my $commandNameSpecialRegExp = q();
    if ( ref( ${ $mainSettings{commandCodeBlocks} }{commandNameSpecial} ) eq "ARRAY" ) {

        my @commandNameSpecial = @{ ${ $mainSettings{commandCodeBlocks} }{commandNameSpecial} };
        $logger->trace("*Looping through array for commandCodeBlocks->commandNameSpecial")
            if $is_t_switch_active;

        # note that the zero'th element in this array contains the amalgamate switch, which we don't want!
        foreach ( @commandNameSpecial[ 1 .. $#commandNameSpecial ] ) {
            $logger->trace("$_") if $is_t_switch_active;
            $commandNameSpecialRegExp .= ( $commandNameSpecialRegExp eq "" ? q() : "|" ) . $_;
        }

        # turn the above into a regexp
        $commandNameSpecialRegExp = qr/$commandNameSpecialRegExp/;
    }

    # details to log file
    $logger->trace("*The special command names regexp is: $commandNameSpecialRegExp (see commandNameSpecial)")
        if $is_t_switch_active;

    # read from fine tuning
    my $commandNameRegExp = qr/${${$mainSettings{fineTuning}}{commands}}{name}/;

    # construct the command regexp
    $commandRegExp = qr/
              (\\|\\@|@)   
              (
               $commandNameRegExp|$commandNameSpecialRegExp      # lowercase|uppercase letters, @, *, numbers
              )                
              (\h*)
              (\R*)?
              ($optAndMandAndRoundBracketsRegExp)
              (\R)?
            /sx;

    # command regexp with trailing comment
    $commandRegExpTrailingComment = qr/$commandRegExp(\h*)((?:$trailingCommentRegExp\h*)*)/;

}

sub tasks_particular_to_each_object {
    my $self = shift;

    # check for adding/removing linebreaks before =
    $self->check_linebreaks_before_equals;

    # search for arguments
    $self->find_opt_mand_arguments;

    # situation: ${${$self}{linebreaksAtEnd}}{end} == 1, and the argument container object
    # still contains a linebreak at the end; in this case, we need to remove the linebreak from
    # the container object
    if (    ${ ${$self}{linebreaksAtEnd} }{end} == 1
        and ${ ${ ${$self}{children} }[0] }{body} =~ m/\R$/s
        and !${$self}{endImmediatelyFollowedByComment} )
    {
        $logger->trace("Removing linebreak from argument container of ${$self}{name}")
            if $is_t_switch_active;
        ${ ${ ${$self}{children} }[0] }{body} =~ s/\R$//s;
        ${ ${ ${ ${$self}{children} }[0] }{linebreaksAtEnd} }{body} = 0;
    }

    # situation: ${${$self}{linebreaksAtEnd}}{end} == 1 and the last argument specifies
    # EndFinishesWithLineBreaks = 0 (see test-cases/commands/just-one-command-mod10.tex)
    if (    ${ ${$self}{linebreaksAtEnd} }{end} == 1
        and defined ${ ${ ${ ${$self}{children} }[0] }{children}[-1] }{EndFinishesWithLineBreak}
        and ${ ${ ${ ${$self}{children} }[0] }{children}[-1] }{EndFinishesWithLineBreak} == -1 )
    {
        $logger->trace(
            "Switching linebreaksAtEnd{end} to be 0 in command ${$self}{name} as last argument specifies EndFinishesWithLineBreak == 0"
        ) if $is_t_switch_active;
        ${ ${$self}{linebreaksAtEnd} }{end} = 0;
        ${$self}{EndFinishesWithLineBreak} = -1;
    }

    # if the last argument finishes with a linebreak, it won't get interpreted at
    # the right time (see test-cases/commands/commands-one-line-nested-simple-mod1.tex for example)
    # so this little bit fixes it
    if (    ${ ${ ${ ${ ${$self}{children} }[0] }{children}[-1] }{linebreaksAtEnd} }{end}
        and ${ ${$self}{linebreaksAtEnd} }{end} == 0
        and defined ${ ${ ${ ${$self}{children} }[0] }{children}[-1] }{EndFinishesWithLineBreak}
        and ${ ${ ${ ${$self}{children} }[0] }{children}[-1] }{EndFinishesWithLineBreak} >= 1
        and !${$self}{endImmediatelyFollowedByComment} )
    {

        # update the Command object
        $logger->trace("Adjusting linebreaksAtEnd in command ${$self}{name}")
            if $is_t_switch_active;
        ${ ${$self}{linebreaksAtEnd} }{end}
            = ${ ${ ${ ${ ${$self}{children} }[0] }{children}[-1] }{linebreaksAtEnd} }{end};
        ${$self}{replacementText} .= "\n";

        # if the last argument has EndFinishesWithLineBreak == 3
        if ( ${ ${ ${ ${$self}{children} }[0] }{children}[-1] }{EndFinishesWithLineBreak} == 3 ) {
            my $EndStringLogFile = ${ ${ ${ ${$self}{children} }[0] }{children}[-1] }{aliases}{EndFinishesWithLineBreak}
                || "EndFinishesWithLineBreak";
            $logger->trace(
                "Adding another blank line to replacement text for ${$self}{name} as last argument has $EndStringLogFile == 3 "
            ) if $is_t_switch_active;
            ${$self}{replacementText} .= (
                ${ $mainSettings{modifyLineBreaks} }{preserveBlankLines}
                ? $tokens{blanklines}
                : "\n"
            ) . "\n";
        }

        # update the argument object
        $logger->trace("Adjusting argument object in command, ${$self}{name}")
            if $is_t_switch_active;
        ${ ${ ${ ${$self}{children} }[0] }{linebreaksAtEnd} }{body} = 0;
        ${ ${ ${$self}{children} }[0] }{body} =~ s/\R$//s;

        # update the last mandatory/optional argument
        $logger->trace("Adjusting last argument in command, ${$self}{name}")
            if $is_t_switch_active;
        ${ ${ ${ ${ ${$self}{children} }[0] }{children}[-1] }{linebreaksAtEnd} }{end} = 0;
        ${ ${ ${ ${$self}{children} }[0] }{children}[-1] }{EndFinishesWithLineBreak} = -1;
        ${ ${ ${ ${$self}{children} }[0] }{children}[-1] }{replacementText} =~ s/\R$//s;

        # output to log file
        $logger->trace( Dumper( ${ ${ ${$self}{children} }[0] }{children}[-1] ) )
            if $is_tt_switch_active;
    }

# situation: ${${$self}{linebreaksAtEnd}}{end} == 1 and the last argument has added
# a line break, which can result in a bogus blank line (see test-cases/commands/just-one-command.tex with mand-args-mod1.yaml)
    if (    ${ ${$self}{linebreaksAtEnd} }{end} == 1
        and defined ${ ${ ${ ${$self}{children} }[0] }{children}[-1] }{EndFinishesWithLineBreak}
        and ${ ${ ${ ${$self}{children} }[0] }{children}[-1] }{EndFinishesWithLineBreak} >= 1
        and ${ ${ ${ ${$self}{children} }[0] }{children}[-1] }{replacementText} =~ m/\R$/s
        and !${$self}{endImmediatelyFollowedByComment} )
    {

        # last argument adjustment
        $logger->trace("Adjusting last argument in command, ${$self}{name} to avoid double line break")
            if $is_t_switch_active;
        ${ ${ ${ ${$self}{children} }[0] }{children}[-1] }{replacementText} =~ s/\R$//s;
        ${ ${ ${ ${ ${$self}{children} }[0] }{children}[-1] }{linebreaksAtEnd} }{end} = 0;

        # argument object adjustment
        $logger->trace("Adjusting argument object in command, ${$self}{name} to avoid double line break")
            if $is_t_switch_active;
        ${ ${ ${ ${$self}{children} }[0] }{linebreaksAtEnd} }{body} = 0;
        ${ ${ ${$self}{children} }[0] }{body} =~ s/\R$//s;
    }

    # the arguments body might finish with horizontal space, in which case, we need to transfer this
    # to the parent object replacement text.
    #
    # see ../test-cases/texexchange/5461.tex which was the first example to demonstrate the need for this
    if (   !${ ${ ${$self}{children} }[0] }{endImmediatelyFollowedByComment}
        and ${ ${ ${$self}{children} }[0] }{body} =~ m/\h*$/
        and ${$self}{replacementText} !~ m/\R$/ )
    {
        $logger->trace(
            "${$self}{name}: trailing horizontal space found in arguments -- removing it from arguments, adding to replacement text"
        ) if $is_t_switch_active;
        ${ ${ ${$self}{children} }[0] }{body} =~ s/(\h*)$//s;
        ${$self}{replacementText} .= "$1";
    }

    # search for ifElseFi blocks
    $self->find_ifelsefi;

    # search for special begin/end
    $self->find_special;

}

sub check_linebreaks_before_equals {

    # empty routine, which allows the above routine to function (this routine kicks in for KeyEqualsValuesBraces)
    return;
}

sub create_unique_id {
    my $self = shift;

    $commandCounter++;
    ${$self}{id} = "$tokens{commands}$commandCounter";
    return;
}

sub align_at_ampersand {

    # need an empty routine here for commands; see
    # test-cases/matrix1.tex for example
    return;
}

sub double_back_slash_else {

    # need an empty routine here for commands; see
    # test-cases/alignment/command-align.tex for example
    return;
}

1;
