package JavaScript::Beautifier;

use warnings;
use strict;
use JavaScript::Packer1 qw/js_packer/;

our $VERSION = '0.25';
our $AUTHORITY = 'cpan:FAYLAND';

use base 'Exporter';
use vars qw/@EXPORT_OK/;
@EXPORT_OK = qw/js_beautify/;

my ( @input, @output, @modes );
my ( $token_text, $last_type, $last_text, $last_last_text, $last_word, $current_mode, $indent_string, $parser_pos, $in_case, $prefix, $token_type, $do_block_just_closed, $var_line, $var_line_tainted, $if_line_flag, $wanted_newline, $just_added_newline );

my @whitespace = split('', "\n\r\t ");
my @wordchar   = split('', 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789_$');
my @digits     = split('', '0123456789');
# <!-- is a special case (ok, it's a minor hack actually)
my @punct      = split(' ', '+ - * / % & ++ -- = += -= *= /= %= == === != !== > < >= <= >> << >>> >>>= >>= <<= && &= | || ! !! , : ? ^ ^= |= ::');
# words which should always start on new line.
my @line_starter = split(',', 'continue,try,throw,return,var,if,switch,case,default,for,while,break,function');

my ( $opt_indent_level, $opt_indent_size, $opt_indent_character, $opt_preserve_newlines, $opt_space_after_anon_function );

sub js_beautify {
    my ( $js_source_code, $opts ) = @_;

    $js_source_code = js_packer($js_source_code);

    $opt_indent_size = $opts->{indent_size} || 4;
    $opt_indent_character = $opts->{indent_character} || ' ';
    $opt_preserve_newlines = exists $opts->{preserve_newlines} ? $opts->{preserve_newlines} : 1;
    $opt_indent_level = $opts->{indent_level} ||= 0;
    $opt_space_after_anon_function = exists $opts->{space_after_anon_function} ? $opts->{space_after_anon_function} : 0;

    # -------------------------------------
    $just_added_newline = 0;
    $indent_string = '';
    while ( $opt_indent_size-- ) {
        $indent_string .= $opt_indent_character;
    }
    @input = split('', $js_source_code);

    $last_word = ''; # last 'TK_WORD' passed
    $last_type = 'TK_START_EXPR'; # last token type
    $last_text = ''; # last token text
    $last_last_text = ''; # pre-last token text
    @output = ();

    $do_block_just_closed = 0;
    $var_line = 0;
    $var_line_tainted = 0;

    # states showing if we are currently in expression (i.e. "if" case) - 'EXPRESSION', or in usual block (like, procedure), 'BLOCK'.
    # some formatting depends on that.
    $current_mode = 'BLOCK';
    @modes = ( $current_mode );

    $parser_pos = 0; # parser position
    $in_case = 0; # flag for parser that case/default has been processed, and next colon needs special attention
    while ( 1 ) {
        my $t = get_next_token($parser_pos);
        $token_text = $t->[0];
        $token_type = $t->[1];
        if ( $token_type eq 'TK_EOF' ) {
            last;
        }

        if ( $token_type eq 'TK_START_EXPR' ) {
            $var_line = 0;

            if ( $token_text eq '[' ) {
                if ( $last_type eq 'TK_WORD' || $last_text eq ')' ) {
                    # this is array index specifier, break immediately
		    # a[x], fn()[x]
                    set_mode('(EXPRESSION)');
                    print_token();
                    $last_last_text = $last_text;$last_type = $token_type;$last_text = $token_text;next;
                }
                if ( $current_mode eq '[EXPRESSION]' || $current_mode eq '[INDENTED-EXPRESSION]' ) {
                    if ( $last_last_text eq ']' && $last_text eq ',' ) {
                        # ], [ goes to new line
                        indent();
                        print_newline();
                        set_mode('[INDENTED-EXPRESSION]');
                    } elsif ($last_text eq '[') {
                        indent();
                        print_newline();
                        set_mode('[INDENTED-EXPRESSION]');
                    } else {
                        set_mode('[EXPRESSION]');
                    }
                } else {
                    set_mode('[EXPRESSION]');
                }
            } else {
                set_mode('(EXPRESSION)');
            }

            if ( $last_text eq ';' || $last_type eq 'TK_START_BLOCK' ) {
                print_newline();
            } elsif ( $last_type eq 'TK_END_EXPR' || $last_type eq 'TK_START_EXPR' ) {
                # do nothing on (( and )( and ][ and ]( ..
            } elsif ( $last_type ne 'TK_WORD' && $last_type ne 'TK_OPERATOR' ) {
                print_space();
            } elsif ( $last_word eq 'function' ) {
                # function() vs function ()
                if ( $opt_space_after_anon_function ) {
                    print_space();
                }
            } elsif ( grep { $last_word eq $_ } @line_starter ) {
                print_space();
            }
            print_token();
            $last_last_text = $last_text;$last_type = $token_type;$last_text = $token_text;next;
        } elsif ( $token_type eq 'TK_END_EXPR' ) {
            if ( $token_text eq ']' && $current_mode eq '[INDENTED-EXPRESSION]' ) {
                unindent();
            }
            restore_mode();
            print_token();
            $last_last_text = $last_text;$last_type = $token_type;$last_text = $token_text;next;
        } elsif ( $token_type eq 'TK_START_BLOCK' ) {
            if ( $last_word eq 'do' ) {
                set_mode('DO_BLOCK');
            } else {
                set_mode('BLOCK');
            }
            if ( $last_type ne 'TK_OPERATOR' && $last_type ne 'TK_START_EXPR' ) {
                if ( $last_type eq 'TK_START_BLOCK' ) {
                    print_newline();
                } else {
                    print_space();
                }
            }
            print_token();
            indent();
            $last_last_text = $last_text;$last_type = $token_type;$last_text = $token_text;next;
        } elsif ( $token_type eq 'TK_END_BLOCK' ) {
            if ( $last_type eq 'TK_START_BLOCK' ) {
                # nothing
                if ($just_added_newline) {
                    remove_indent();
                    #  {
                    #
                    #  }
                } else {
                    #  {}
                    trim_output();
                }
                unindent();
            } else {
                unindent();
                print_newline();
            }
            print_token();
            restore_mode();
            $last_last_text = $last_text;$last_type = $token_type;$last_text = $token_text;next;
        } elsif ( $token_type eq 'TK_WORD' ) {
            # no, it's not you. even I have problems understanding how this works
            # and what does what.
            if ( $do_block_just_closed ) {
                print_space();
                print_token();
                print_space();
                $do_block_just_closed = 0;
                $last_last_text = $last_text;$last_type = $token_type;$last_text = $token_text;next;
            }
            if ( $token_text eq 'case' || $token_text eq 'default' ) {
                if ( $last_text eq ':' ) {
                    # switch cases following one another
                    remove_indent();
                } else {
                    # case statement starts in the same line where switch
                    unindent();
                    print_newline();
                    indent();
                }
                print_token();
                $in_case = 1;
                $last_last_text = $last_text;$last_type = $token_type;$last_text = $token_text;next;
            }
            $prefix = 'NONE';
            if ( $last_type eq 'TK_END_BLOCK' ) {
                if ( not (grep { lc($token_text) eq $_ } ('else', 'catch', 'finally')) ) {
                    $prefix = 'NEWLINE';
                } else {
                    $prefix = 'SPACE';
                    print_space();
                }
            } elsif ( $last_type eq 'TK_SEMICOLON' && ( $current_mode eq 'BLOCK' || $current_mode eq 'DO_BLOCK' ) ) {
                $prefix = 'NEWLINE';
            } elsif ( $last_type eq 'TK_SEMICOLON' && is_expression($current_mode) ) {
                $prefix = 'SPACE';
            } elsif ( $last_type eq 'TK_STRING') {
                $prefix = 'NEWLINE';
            } elsif ( $last_type eq 'TK_WORD' ) {
                $prefix = 'SPACE';
            } elsif ( $last_type eq 'TK_START_BLOCK') {
                $prefix = 'NEWLINE';
            } elsif ( $last_type eq 'TK_END_EXPR' ) {
                print_space();
                $prefix = 'NEWLINE';
            }

            if ( $last_type ne 'TK_END_BLOCK' && (grep { lc($token_text) eq $_ } ('else', 'catch', 'finally')) ) {
                print_newline();
            } elsif ( (grep { $token_text eq $_ } @line_starter) || $prefix eq 'NEWLINE' ) {
                if ( $last_text eq 'else' ) {
                    # no need to force newline on else break
                    print_space();
                } elsif ( ( $last_type eq 'TK_START_EXPR' || $last_text eq '=' || $last_text eq ',' ) && $token_text eq 'function' ) {
                    # no need to force newline on 'function': (function
                    # DONOTHING
                } elsif ( $last_text eq 'return' || $last_text eq 'throw' ) {
                    # no newline between 'return nnn'
                    print_space();
                } elsif ( $last_type ne 'TK_END_EXPR' ) {
                    if ( ($last_type ne 'TK_START_EXPR' || $token_text ne 'var') && $last_text ne ':' ) {
                        # no need to force newline on 'var': for (var x = 0...)
                        if ( $token_text eq 'if' && $last_word eq 'else' && $last_text ne '{' ) {
                            # no newline for } else if {
                            print_space();
                        }  else {
                            print_newline();
                        }
                    }
                } else {
                    if ( (grep { $token_text eq $_ } @line_starter) && $last_text ne ')' ) {
                        print_newline();
                    }
                }
            } elsif ( $prefix eq 'SPACE' ) {
                print_space();
            }
            print_token();
            $last_word = $token_text;
            if ( $token_text eq 'var' ) {
                $var_line = 1;
                $var_line_tainted = 0;
            }
            if ( $token_text eq 'if' || $token_text eq 'else' ) {
                $if_line_flag = 1;
            }
            $last_last_text = $last_text;$last_type = $token_type;$last_text = $token_text;next;
        } elsif ( $token_type eq 'TK_SEMICOLON' ) {
            print_token();
            $var_line = 0;
            $last_last_text = $last_text;$last_type = $token_type;$last_text = $token_text;next;
        } elsif ( $token_type eq 'TK_STRING' ) {
            if ( $last_type eq 'TK_START_BLOCK' || $last_type eq 'TK_END_BLOCK' || $last_type eq 'TK_SEMICOLON' ) {
                print_newline();
            } elsif ( $last_type eq 'TK_WORD' ) {
                print_space();
            }
            print_token();
            $last_last_text = $last_text;$last_type = $token_type;$last_text = $token_text;next;
        } elsif ( $token_type eq 'TK_OPERATOR' ) {
            my $start_delim = 1;
            my $end_delim = 1;
            if ( $var_line && $token_text ne ',' ) {
                $var_line_tainted = 1;
                if ( $token_text eq ':' ) {
                    $var_line = 0;
                }
            }
            if ($var_line && $token_text eq ',' && is_expression($current_mode) ) {
                # do not break on comma, for(var a = 1, b = 2)
                $var_line_tainted = 0;
            }
            if ( $token_text eq ':' && $in_case ) {
                print_token(); # colon really asks for separate treatment
                print_newline();
                $in_case = 0;
                $last_last_text = $last_text;$last_type = $token_type;$last_text = $token_text;next;
            }
            if ( $token_text eq '::' ) {
                # no spaces around exotic namespacing syntax operator
                print_token();
                $last_last_text = $last_text;$last_type = $token_type;$last_text = $token_text;next;
            }

            if ( $token_text eq ',' ) {
                if ($var_line) {
                    if ( $var_line_tainted ) {
                        print_token();
                        print_newline();
                        $var_line_tainted = 0;
                    } else {
                        print_token();
                        print_space();
                    }
                } elsif ( $last_type eq 'TK_END_BLOCK' ) {
                    print_token();
                    print_newline();
                } else {
                    if ( $current_mode eq 'BLOCK' ) {
                        print_token();
                        print_newline();
                    } else {
                        # EXPR or DO_BLOCK
                        print_token();
                        print_space();
                    }
                }
                $last_last_text = $last_text;$last_type = $token_type;$last_text = $token_text;next;
            } elsif ( $token_text eq '--' || $token_text eq '++' ) { # unary operators special case
                if ( $last_text eq ';' ) {
                    if ( $current_mode eq 'BLOCK') {
                        # { foo; --i }
                        print_newline();
                        $start_delim = 1;
                        $end_delim = 0;
                    } else {
                        # space for (;; ++i)
                        $start_delim = 1;
                        $end_delim = 0;
                    }
                } else {
                    if ($last_text eq '{') {
                        # {--i
                        print_newline();
                    }
                    $start_delim = 0;
                    $end_delim = 0;
                }
            } elsif ( ( $token_text eq '!' || $token_text eq '+' || $token_text eq '-' ) && ($last_text eq 'return' || $last_text eq 'case') ) {
                $start_delim = 1;
                $end_delim = 0;
            } elsif ( ( $token_text eq '!' || $token_text eq '+' || $token_text eq '-' ) && $last_type eq 'TK_START_EXPR' ) {
                # special case handling: if (!a)
                $start_delim = 0;
                $end_delim = 0;
            } elsif ( $last_type eq 'TK_OPERATOR' ) {
                $start_delim = 0;
                $end_delim = 0;
            } elsif ( $last_type eq 'TK_END_EXPR' ) {
                $start_delim = 1;
                $end_delim = 1;
            } elsif ( $token_text eq '.' ) {
                # decimal digits or object.property
                $start_delim = 0;
                $end_delim = 0;
            } elsif ( $token_text eq ':' ) {
                if (is_ternary_op()) {
                    $start_delim = 1;
                } else {
                    $start_delim = 0;
                }
            }
            if ( $start_delim ) {
                print_space();
            }
            print_token();
            if ( $end_delim ) {
                print_space();
            }
            $last_last_text = $last_text;$last_type = $token_type;$last_text = $token_text;next;
        } elsif ($token_type eq 'TK_BLOCK_COMMENT') {
            print_newline();
            print_token();
            print_newline();
            $last_last_text = $last_text;$last_type = $token_type;$last_text = $token_text;next;
        } elsif ($token_type eq 'TK_COMMENT') {
            # print_newline();
            print_space();
            print_token();
            print_newline();
            $last_last_text = $last_text;$last_type = $token_type;$last_text = $token_text;next;
        } elsif ($token_type eq 'TK_UNKNOWN') {
            print_token();
            $last_last_text = $last_text;$last_type = $token_type;$last_text = $token_text;next;
        }
        $last_type = $token_type;
        $last_text = $token_text;
    }

    my $output = join('', @output);
    $output =~ s/\n+$//;
    return $output;
}

sub trim_output {
    while ( scalar @output && ( $output[ scalar @output - 1 ] eq ' ' || $output[ scalar @output - 1 ] eq $indent_string ) ) {
        pop @output;
    }
}
sub print_newline {
    my ( $ignore_repeated ) = @_;
    $ignore_repeated = 1 unless defined $ignore_repeated;
    $if_line_flag = 0;
    trim_output();

    if ( not scalar @output ) {
        return; # no newline on start of file
    }

    if ( $output[ scalar @output - 1 ] ne "\n" || ! $ignore_repeated ) {
        $just_added_newline = 1;
        push @output, "\n";
    }
    foreach my $i ( 0 .. $opt_indent_level - 1 ) {
        push @output, $indent_string;
    }
}

sub print_space {
    my $last_output = ' ';
    $last_output = $output[ scalar @output - 1 ] if scalar @output;
    if ( $last_output ne ' ' && $last_output ne "\n" && $last_output ne $indent_string ) { # prevent occassional duplicate space
        push @output, ' ';
    }
}

sub print_token {
    $just_added_newline = 0;
    push @output, $token_text;
}
sub indent {
    $opt_indent_level++;
}
sub unindent {
    if ( $opt_indent_level ) {
        $opt_indent_level--;
    }
}
sub remove_indent {
    if ( scalar @output && $output[ scalar @output - 1 ] eq $indent_string ) {
        pop @output;
    }
}
sub set_mode {
    my $mode = shift;
    push @modes, $current_mode;
    $current_mode = $mode;
}
sub is_expression {
    my $mode = shift;
    return ($mode eq '[EXPRESSION]' || $mode eq '[INDENTED-EXPRESSION]' || $mode eq '(EXPRESSION)') ? 1 : 0;
}
sub restore_mode {
    $do_block_just_closed = ( $current_mode eq 'DO_BLOCK' ) ? 1 : 0;
    $current_mode = pop @modes;
}

# Walk backwards from the colon to find a '?' (colon is part of a ternary op)
# or a '{' (colon is part of a class literal). Along the way, keep track of
# the blocks and expressions we pass so we only trigger on those chars in our
# own level, and keep track of the colons so we only trigger on the matching '?'.
sub is_ternary_op {
    my $level = 0;
    my $colon_count = 0;
    foreach my $o (reverse @output) {
        if ( $o eq ':' ) {
            if ( $level == 0 ) {
                $colon_count++;
            }
            next;
        } elsif ( $o eq '?' ) {
            if ( $level == 0 ) {
                if ( $colon_count == 0 ) {
                    return 1;
                } else {
                    $colon_count--;
                }
            }
            next;
        } elsif ( $o eq '{' ) {
            if ( $level == 0 ) {
                return 0;
            }
            $level--;
            next;
        }
        if ( $o eq '(' or $o eq '[' ) {
            $level--;
            next;
        } elsif ( $o eq ')' or $o eq ']' or $o eq '}' ) {
            $level++;
            next;
        }
    }
}

sub get_next_token {
    my $n_newlines = 0;

    if ( $parser_pos >= scalar @input ) {
        return ['', 'TK_EOF'];
    }

    my $c = $input[$parser_pos];
    $parser_pos++;

    while ( grep { $_ eq $c } @whitespace ) {
        if ( $parser_pos >= scalar @input ) {
            return ['', 'TK_EOF'];
        }
        if ( $c eq "\n" ) {
            $n_newlines += 1;
        }
        $c = $input[$parser_pos];
        $parser_pos++;
    };
    $wanted_newline = 0;
    if ( $opt_preserve_newlines ) {
        if ( $n_newlines > 1 ) {
            foreach my $i ( 0 .. 1 ) {
                my $flag = ( $i == 0 ) ? 1 : 0;
                print_newline( $flag );
            }
        }
        $wanted_newline = ($n_newlines == 1) ? 1 : 0;
    }
    if ( grep { $c eq $_ } @wordchar ) {
        if ( $parser_pos < scalar @input ) {
            while ( grep { $input[$parser_pos] eq $_ } @wordchar ) {
                $c .= $input[$parser_pos];
                $parser_pos++;
                if ( $parser_pos == scalar @input ) {
                    last;
                }
            }
        }

        # small and surprisingly unugly hack for 1E-10 representation
        if ( $parser_pos != scalar @input && $c =~ /^[0-9]+[Ee]$/ && ($input[$parser_pos] eq '-' || $input[$parser_pos] eq '+') ) {
            my $sign = $input[$parser_pos];
            $parser_pos++;
            my $t = get_next_token($parser_pos);
            $c .= $sign . $t->[0];
            return [$c, 'TK_WORD'];
        }
        if ( $c eq 'in' ) { # hack for 'in' operator
            return [$c, 'TK_OPERATOR'];
        }
        if ( $wanted_newline && $last_type ne 'TK_OPERATOR' && not $if_line_flag ) {
            print_newline();
        }
        return [$c, 'TK_WORD'];
    }
    if ( $c eq '(' || $c eq '[' ) {
        return [$c, 'TK_START_EXPR'];
    }
    if ( $c eq ')' || $c eq ']' ) {
        return [$c, 'TK_END_EXPR'];
    }
    if ( $c eq '{' ) {
        return [$c, 'TK_START_BLOCK'];
    }
    if ( $c eq '}' ) {
        return [$c, 'TK_END_BLOCK'];
    }
    if ( $c eq ';' ) {
        return [$c, 'TK_SEMICOLON'];
    }
    if ( $c eq '/' ) {
        my $comment;
        # peek for comment /* ... */
        if ( $input[$parser_pos] eq '*' ) {
            $parser_pos++;
            if ( $parser_pos < scalar @input ) {
                while (not ( $input[$parser_pos] eq '*' && $input[$parser_pos+1] && $input[$parser_pos+1] eq '/') && $parser_pos < scalar @input ) {
                    $comment .= $input[$parser_pos];
                    $parser_pos++;
                    if ( $parser_pos >= scalar @input ) {
                        last;
                    }
                }
            }
            $parser_pos += 2;
            return ['/*' . $comment . '*/', 'TK_BLOCK_COMMENT'];
        }
        # peek for comment // ...
        if ( $input[$parser_pos] eq '/' ) {
            $comment = $c;
            while ( $input[$parser_pos] ne "\x0d" && $input[$parser_pos] ne "\x0a" ) {
                $comment .= $input[$parser_pos];
                $parser_pos++;
                if ( $parser_pos >= scalar @input ) {
                    last;
                }
            }
            $parser_pos++;
            if ($wanted_newline) {
                print_newline();
            }
            return [$comment, 'TK_COMMENT'];
        }
    }
    if ( $c eq "'" || # string
         $c eq '"' || # string
        ($c eq '/' &&
        (( $last_type eq 'TK_WORD' && $last_text eq 'return') ||
         ( $last_type eq 'TK_START_EXPR' || $last_type eq 'TK_START_BLOCK' || $last_type eq 'TK_END_BLOCK' || $last_type eq 'TK_OPERATOR' || $last_type eq 'TK_EOF' || $last_type eq 'TK_SEMICOLON')))) { # regexp
         my $sep = $c;
         my $esc = 0;
         my $resulting_string = $c;
         if ( $parser_pos < scalar @input ) {
            if ( $sep eq '/') {
                # handle regexp separately...
                my $in_char_class = 0;
                while ( $esc || $in_char_class || $input[$parser_pos] ne $sep ) {
                    $resulting_string .= $input[$parser_pos];
                    if ( not $esc ) {
                        $esc = ( $input[$parser_pos] eq '\\' ) ? 1 : 0;
                        if ( $input[$parser_pos] eq '[' ) {
                            $in_char_class = 1;
                        } elsif ( $input[$parser_pos] eq ']' ) {
                            $in_char_class = 0;
                        }
                    } else {
                        $esc = 0;
                    }
                    $parser_pos++;
                    if ( $parser_pos >= scalar @input ) {
                        # incomplete string/rexp when end-of-file reached.
                        # bail out with what had been received so far.
                        return [$resulting_string, 'TK_STRING'];
                     }
                 }

             } else {
                # and handle string also separately
                while ( $esc || $input[$parser_pos] ne $sep ) {
                    $resulting_string .= $input[$parser_pos];
                    if ( not $esc ) {
                        $esc = ( $input[$parser_pos] eq '\\' ) ? 1 : 0;
                    } else {
                        $esc = 0;
                    }
                    $parser_pos++;
                    if ( $parser_pos >= scalar @input ) {
                        # incomplete string/rexp when end-of-file reached.
                        # bail out with what had been received so far.
                        return [$resulting_string, 'TK_STRING'];
                     }
                }
            }
         }
         $parser_pos++;
         $resulting_string .= $sep;
         if ( $sep eq '/' ) {
             # regexps may have modifiers /regexp/MOD , so fetch those, too
             while ( $parser_pos < scalar @input && (grep { $input[$parser_pos] eq $_ } @wordchar) ) {
                 $resulting_string .= $input[$parser_pos];
                 $parser_pos++;
            }
        }
        return [$resulting_string, 'TK_STRING'];
    }

    if ($c eq '#') {
        # Spidermonkey-specific sharp variables for circular references
        # https://developer.mozilla.org/En/Sharp_variables_in_JavaScript
        # http://mxr.mozilla.org/mozilla-central/source/js/src/jsscan.cpp around line 1935
        my $sharp = '#';
        if ($parser_pos < scalar @input && (grep { $input[$parser_pos] eq $_ } @digits) ) {
            do {
                $c = $input[$parser_pos];
                $sharp .= $c;
                $parser_pos += 1;
            } while ($parser_pos < scalar @input && $c ne '#' && $c ne '=');
            if ($c eq '#') {
                return [$sharp, 'TK_WORD'];
            } else {
                return [$sharp, 'TK_OPERATOR'];
            }
        }
    }

    if ($c eq '<' && $parser_pos + 2 < scalar @input && join('', @input[$parser_pos-1 .. $parser_pos+2]) eq '<!--') {
        $parser_pos += 3;
        return ['<!--', 'TK_COMMENT'];
    }
    if ($c eq '-' && $parser_pos + 1 < scalar @input && join('', @input[$parser_pos-1 .. $parser_pos+1]) eq '-->') {
        $parser_pos += 2;
        if ($wanted_newline) {
            print_newline();
        }
        return ['-->', 'TK_COMMENT'];
    }

    if ( grep { $c eq $_ } @punct ) {
         while ( $parser_pos < scalar @input && (grep { $c . $input[$parser_pos] eq $_ } @punct) ) {
             $c .= $input[$parser_pos];
             $parser_pos++;
             last if ( $parser_pos >= scalar @input );
         }
         return [$c, 'TK_OPERATOR'];
    }
    return [$c, 'TK_UNKNOWN'];
}

1;
__END__

=head1 NAME

JavaScript::Beautifier - Beautify Javascript (beautifier for javascript)

=head1 SYNOPSIS

    use JavaScript::Beautifier qw/js_beautify/;

    my $pretty_js = js_beautify( $js_source_code, {
        indent_size => 4,
        indent_character => ' ',
    } );

=head1 DESCRIPTION

This module is mostly a Perl-rewrite of L<http://github.com/einars/js-beautify/tree/master/beautify.js>

You can check it through L<http://jsbeautifier.org/>

=head1 FUNCTIONS

$js_source_code = <<'EOF';
  a = 12;
  {return '\\w+';}
EOF

=head2 js_beautify( $js_source_code, $opts );

Beautify javascript source code contained in a string with the included options, described below.

=head3 Options

=over 4

=item indent_size

=item indent_character

if you prefer Tab than Space, try:

    {
        indent_size => 1,
        indent_character => "\t",
    }

=item preserve_newlines

Default is 1

    my $in = "var\na=dont_preserve_newlines";
    my $out = "var a = dont_preserve_newlines";
    my $js = js_beautify( $in, { preserve_newlines => 0 } );
    # $out eq $js
    $in = "var\na=do_preserve_newlines";
    $out = "var\na = do_preserve_newlines";
    $js = js_beautify( $in, { preserve_newlines => 1 } );
    # $out eq $js

=item space_after_anon_function

Default is 0

=back

=head1 AUTHOR

Fayland Lam, C<< <fayland at gmail.com> >>

=head1 COPYRIGHT & LICENSE

Copyright 2008-2018 Fayland Lam, all rights reserved.

This program is free software; you can redistribute it and/or modify it
under the same terms as Perl itself.

=cut