package Data::QuickMemoPlus::Reader;
use 5.008001;
use strict;
use warnings;
use JSON;
use Archive::Zip qw( :ERROR_CODES :CONSTANTS );

our $VERSION = "0.01";

use Exporter qw(import);
 
our @EXPORT_OK = qw( lqm_to_str );
our $suppress_header = 0;

sub lqm_to_str {
    ## pass an lqm file exported from QuickMemo+
    my ( $lqm_file ) = @_;
    if (not -f $lqm_file){
        warn "$lqm_file is not a file";
        return '';
    }
    my $note_created_time = "";
    if ( $lqm_file =~ /(QuickMemo\+_(\d{6}_\d{6})(\(\d+\))?)/i) {
        $note_created_time = $2;
    }
    my $ref_json_str = extract_json_from_lqm( $lqm_file );
    return '' if not $ref_json_str;
    my ($extracted_text, $note_category) = extract_text_from_json($ref_json_str);
    my $header = "Created date: $note_created_time\n";
    $header .= "Category:   $note_category\n";
    $header .= "-"x79 . "\n";
    $header = '' if $suppress_header;
    return $header . $extracted_text;
}

#####################################
#         Unzip jlqm file and 
#           return json file contents.
#
sub extract_json_from_lqm {
    #   unzip
    #   extract the memoinfo.jlqm file.
    my $lqm_file = shift;
    # Read a Zip file
    my $lqm_zip = Archive::Zip->new();
    unless ( $lqm_zip->read( $lqm_file ) == AZ_OK ) {
        warn "Error reading $lqm_file";
        ####### to do: add the zip error to the warning?
        return "";
    }
    my $jlqm_filename = "memoinfo.jlqm";
    my $member = $lqm_zip->memberNamed( $jlqm_filename );
    ############### to do: add warning here if memoinfo.jlqm is missing.
    if( not $member ){
        warn "File not found: $jlqm_filename in archive $lqm_file";
        return "";
    }
    my ( $string, $status ) = $member->contents();
    if(not $status == AZ_OK){
        warn "Error extracting $jlqm_filename from $lqm_file : Status = $status";
        return "";
    }
    return \$string;
}

###############################################
#       Decode json file contents and
#         return the text in 'DescRaw'
sub extract_text_from_json {
    my $ref_json_string = shift;
    
    ############# To do: eval this and trap errors.
    my $href_memo  = decode_json $$ref_json_string;
    if (not $href_memo){
        warn "Error decoding text";
        return '','';
    }
    my $text = "";
    foreach( @{$href_memo->{MemoObjectList}} ) {
        $text .= $_->{DescRaw};
        $text .= "\n";
    }
    my $category = $href_memo->{Category}->{CategoryName};
    $category //= '';
    $category =~ s/[^\w-]/_/;
    return $text, $category;
}
1;
__END__