package BookmarkApp;
use strict;
use warnings;
use base qw{CGI::Application};

use CGI::Application::Plugin::TT;

use Encode;
use HTTP::Date qw{time2isoz};
use JSON;
use Bookmarks;

use URI;
my $base_uri = URI->new;
$base_uri->scheme('http');
$base_uri->host($ENV{HTTP_X_FORWARDED_HOST} || $ENV{SERVER_NAME});
$base_uri->port($ENV{SERVER_PORT});
$base_uri->path($ENV{SCRIPT_NAME} . '/');

my $dbname = 'fk.db';
my $bookmarks = Bookmarks->new({
    dbname   => $dbname,
    base_uri => $base_uri->canonical,
});

sub setup {
    my $self = shift;
    $self->mode_param(path_info => 1);
    $self->run_modes([qw{
        list
        feed
        view
        edit
    }]);
}

sub list {
    my $self = shift;
    my $q = $self->query;

    # check for a uri param, and if there is one present,
    # see if a bookmark for that URI already exists
    if (defined(my $uri = $q->param('uri'))) {
        my $bookmark = $bookmarks->get_bookmark({ uri => $uri });
        if ($bookmark) {
            # redirect to the view of the existing bookmark
            $self->header_type('redirect');
            $self->header_props(
                -uri => $q->url . '/' . $bookmark->{id},
            );
            return;
        } else {
            # bookmark was not found; show the form to create a new bookmark
            $bookmark->{uri} = $uri;
            $bookmark->{title} = $q->param('title');
            $self->header_props(
                -type    => 'text/html',
                -charset => 'UTF-8',
                -status  => 404,
            );
            return $self->tt_process(
                'bookmark.tt',
                $bookmark,
            );
        }
    }

    # list all the bookmarks 
    my $format = $q->param('format') || 'html';
    my $tag = $q->param('tag');
    my @tags = $q->param('tag');
    # special case: handle the empty tag
    if (@tags == 1 && $tags[0] eq '') {
        @tags = ();
    }
    my $limit = $q->param('limit');
    my $offset = $q->param('offset');
    my @resources = $bookmarks->get_resources({
        tag    => \@tags,
        limit  => $limit,
        offset => $offset,
    });
    my @all_tags = $bookmarks->get_tags({ selected => $tag });
    my @cotags = $bookmarks->get_cotags({ tag => \@tags });

    if ($format eq 'json') {
        $self->header_props(
            -type    => 'application/json',
            -charset => 'UTF-8',
        );
        return decode_utf8(
            encode_json({
                bookmarks => \@resources,
            })
        );
    } elsif ($format eq 'xbel') {
        require XML::XBEL;
        #TODO: conditional support; if XML::XBEL is not present, return a 5xx response

        my $xbel = XML::XBEL->new;

        $xbel->new_document({
            title => 'Bookmarks' . ($tag ? " tagged as $tag" : ''),
        });

        for my $bookmark (@resources) {
            my $cdatetime = time2isoz $bookmark->{ctime};
            my $mdatetime = time2isoz $bookmark->{mtime};
            # make the timestamps W3C-correct
            s/ /T/ foreach ($cdatetime, $mdatetime);

            $xbel->add_bookmark({
                href     => $bookmark->{uri},
                title    => $bookmark->{title},
                desc     => 'Tags: ' . join(', ', @{ $bookmark->{tags} }),
                added    => $cdatetime,
                #XXX: are we sure that modified is the mtime of the bookmark or the resource?
                modified => $mdatetime,
            });
        }

        $self->header_props(
            -type    => 'application/xml',
            -charset => 'UTF-8',
        );

        return $xbel->toString;
    } else {
        $self->header_props(
            -type    => 'text/html',
            -charset => 'UTF-8',
        );

        # set the base URL, adding a trailing slash if needed
        my $base_url = $q->url;
        $base_url .= '/' if $base_url =~ m{/bookmarks$};

        my @links = (
            {
                text => 'Link',
                type => 'text/html',
                rel  => 'self',
                query => {
                    tag => \@tags,
                },
            },
            {
                text => 'JSON',
                type => 'application/json',
                rel  => 'alternate',
                query => {
                    tag => \@tags,
                    format => 'json',
                },
            },
            {
                text => 'XBEL',
                type => 'application/xml',
                rel  => 'alternate',
                query => {
                    tag => \@tags,
                    format => 'xbel',
                },
            },
            {
                text => 'Atom',
                type => 'application/atom+xml',
                rel  => 'alternate',
                path => 'feed',
                query => {
                    tag => \@tags,
                },
            },
        );
        for my $link (@links) {
            $link->{href} = URI->new_abs($link->{path} || '', $base_uri);
            $link->{href}->query_form($link->{query});
        }
        
        return $self->tt_process(
            'list.tt',
            {
                base_url     => $base_url,
                selected_tag => $tag,
                search_tags  => \@tags,
                links        => \@links,
                all_tags     => \@all_tags,
                cotags       => \@cotags,
                resources    => \@resources,
            },
        );
    }
}

sub feed {
    my $self = shift;
    my $q = $self->query;

    my $tag = $q->param('tag');

    require XML::Atom::Feed;
    require XML::Atom::Entry;
    require XML::Atom::Link;

    my $feed = XML::Atom::Feed->new;
    $feed->title('Bookmarks' . ($tag ? " tagged as $tag" : ''));
    $feed->id($base_uri->canonical . 'feed');

    # construct a feed from the most recent 12 bookmarks
    for my $bookmark ($bookmarks->get_resources({ tag => $tag, limit => 12 })) {
        my $entry = XML::Atom::Entry->new;
        $entry->id($bookmark->{bookmark_uri});
        $entry->title($bookmark->{title});
        my $link = XML::Atom::Link->new;
        $link->href($bookmark->{uri});
        $entry->add_link($link);
        $entry->summary('Tags: ' . join(', ', @{ $bookmark->{tags} }));
        $feed->add_entry($entry);
    }

    $self->header_props(
        -type => 'application/atom+xml',
        -charset => 'UTF-8',
    );
    return $feed->as_xml;
}

sub view {
    my $self = shift;
    my $id = $self->param('id');
    my $field = $self->param('field');
    my $format = $self->query->param('format') || 'html';

    my $bookmark = $bookmarks->get_bookmark({ id => $id });
    if ($bookmark) {
        if ($field) {
            # respond with just the requested field as plain text
            $self->header_props(
                -type    => 'text/plain',
                -charset => 'UTF-8',
            );
            my $value = $bookmark->{$field};
            return ref $value eq 'ARRAY' ? join(',', @{ $value }) : $value;
        } else {
            if ($format eq 'json') {
                $self->header_props(
                    -type    => 'application/json',
                    -charset => 'UTF-8',
                );
                return decode_utf8(encode_json($bookmark));
            } else {
                # display the bookmark form for this bookmark
                $bookmark->{exists} = 1;
                $bookmark->{created} = "Created " . localtime($bookmark->{ctime});
                $bookmark->{created} .= '; Updated ' . localtime($bookmark->{mtime}) unless $bookmark->{ctime} == $bookmark->{mtime};
                $self->header_props(
                    -type    => 'text/html',
                    -charset => 'UTF-8',
                );
                return $self->tt_process(
                    'bookmark.tt',
                    $bookmark,
                );
            }
        }
    } else {
        $self->header_props(
            -type    => 'text/html',
            -charset => 'UTF-8',
            -status  => 404,
        );
        return "Bookmark $id Not Found";
    }
}

#TODO: split this into edit and create methods
sub edit {
    my $self = shift;
    my $q = $self->query;
    #TODO: get the bookmark based on the id and edit it directly?
    #TODO: deal with changing URIs
    my $uri = $q->param('uri');
    my $title = $q->param('title');
    my @tags = split ' ', $q->param('tags');
    $bookmarks->add({
        uri   => $uri,
        title => $title,
        tags  => \@tags,
    });

=begin

    my $location = URI->new($q->url);
    $location->query_form(uri => $uri) if defined $q->url_param('uri');
    $location->fragment('updated');

=cut

    # return to the form
    $self->header_type('redirect');
    $self->header_props(
        -uri => $ENV{REQUEST_URI},
        -status => 303,
    );
}

1;