#!/usr/bin/perl -w -I../perllib

# alert.cgi:
# Alert code for FixMyStreet
#
# Copyright (c) 2007 UK Citizens Online Democracy. All rights reserved.
# Email: matthew@mysociety.org. WWW: http://www.mysociety.org
#
# $Id: alert.cgi,v 1.14 2007-09-03 21:03:31 matthew Exp $

use strict;
use Standard;
use Digest::SHA1 qw(sha1_hex);
use CrossSell;
use mySociety::Alert;
use mySociety::AuthToken;
use mySociety::Config;
use mySociety::EmailUtil qw(is_valid_email);
use mySociety::Gaze;
use mySociety::MaPit;
use mySociety::VotingArea;
use mySociety::Web qw(ent);

sub main {
    my $q = shift;
    my $out = '';
    my $title = 'Confirmation';
    if ($q->param('signed_email')) {
        $out = alert_signed_input($q);
    } elsif (my $token = $q->param('token')) {
        my $data = mySociety::AuthToken::retrieve('alert', $token);
        if ($data->{id}) {
            $out = alert_token($q, $data);
        } else {
            $out = $q->p(_(<<EOF));
Thank you for trying to confirm your alert. We seem to have a problem ourselves
though, so <a href="/contact">please let us know what went on</a> and we'll look into it.
EOF
        }
    } elsif ($q->param('rss')) {
        $out = alert_rss($q);
        return unless $out;
    } elsif ($q->param('email')) {
        $out = alert_do_subscribe($q, $q->param('email'));
    } elsif ($q->param('id')) {
        $out = alert_updates_form($q);
    } elsif ($q->param('pc')) {
        $title = 'Local RSS feeds and email alerts';
        $out = alert_list($q);
    } else {
        $title = 'Local RSS feeds and email alerts';
        $out = alert_front_page($q);
    }

    print Page::header($q, title => $title);
    print $out;
    print Page::footer();
}
Page::do_fastcgi(\&main);

sub alert_list {
    my ($q, @errors) = @_;
    my %input = map { $_ => scalar $q->param($_) } qw(pc email);
    my %input_h = map { $_ => $q->param($_) ? ent($q->param($_)) : '' } qw(pc email);
    my ($x, $y, $e, $n, $error) = Page::geocode($input{pc});
    return alert_front_page($q, $error) if $error;

    my $errors = '';
    $errors = '<ul id="error"><li>' . join('</li><li>', @errors) . '</li></ul>' if @errors;

    my @types = (@$mySociety::VotingArea::council_parent_types, @$mySociety::VotingArea::council_child_types);
    my %councils = map { $_ => 1 } @$mySociety::VotingArea::council_parent_types;

    my $areas = mySociety::MaPit::get_voting_areas_by_location({easting=>$e, northing=>$n}, 'polygon', \@types);
    $areas = mySociety::MaPit::get_voting_areas_info([ keys %$areas ]);

    my ($options);
    if (keys %$areas == 2) {

        # One-tier council
        my (@options, $council, $ward);
        foreach (values %$areas) {
            if ($councils{$_->{type}}) {
                $council = $_;
            } else {
                $ward = $_;
            }
        }
        push @options, [ 'council', $council->{area_id}, Page::short_name($council->{name}),
            "Problems within $council->{name}" ];
        push @options, [ 'ward', $council->{area_id}.':'.$ward->{area_id}, Page::short_name($council->{name}) . '/'
            . Page::short_name($ward->{name}), "Problems within $ward->{name} ward" ];

        $options = '<div>' . $q->ul({id=>'rss_feed'},
            alert_list_options($q, @options)
        );

    } elsif (keys %$areas == 4) {

        # Two-tier council
        my (@options, $county, $district, $c_ward, $d_ward);
        foreach (values %$areas) {
            if ($_->{type} eq 'CTY') {
                $county = $_;
            } elsif ($_->{type} eq 'DIS') {
                $district = $_;
            } elsif ($_->{type} eq 'CED') {
                $c_ward = $_;
            } elsif ($_->{type} eq 'DIW') {
                $d_ward = $_;
            }
        }
        push @options,
            [ 'area', $district->{area_id}, Page::short_name($district->{name}), $district->{name} ],
            [ 'area', $district->{area_id}.':'.$d_ward->{area_id}, Page::short_name($district->{name}) . '/'
              . Page::short_name($d_ward->{name}), "$d_ward->{name} ward, $district->{name}" ],
            [ 'area', $county->{area_id}, Page::short_name($county->{name}), $county->{name} ],
            [ 'area', $county->{area_id}.':'.$c_ward->{area_id}, Page::short_name($county->{name}) . '/'
              . Page::short_name($c_ward->{name}), "$c_ward->{name} ward, $county->{name}" ];
        $options = '<div id="rss_list">';
        $options .= $q->p($q->strong('Problems within the boundary of:')) .
            $q->ul(alert_list_options($q, @options));
        @options = ();
        push @options,
            [ 'council', $district->{area_id}, Page::short_name($district->{name}), $district->{name} ],
            [ 'ward', $district->{area_id}.':'.$d_ward->{area_id}, Page::short_name($district->{name}) . '/' . Page::short_name($d_ward->{name}),
              "$district->{name}, within $d_ward->{name} ward" ],
            [ 'council', $county->{area_id}, Page::short_name($county->{name}), $county->{name} ],
            [ 'ward', $county->{area_id}.':'.$c_ward->{area_id}, Page::short_name($county->{name}) . '/'
              . Page::short_name($c_ward->{name}), "$county->{name}, within $c_ward->{name} ward" ];
        $options .= $q->p($q->strong('Or problems reported to:')) .
            $q->ul(alert_list_options($q, @options));
        $options .= '</div>
<div id="rss_buttons">
';

    } else {
        # Hopefully impossible in the UK!
        throw Error::Simple('An area with three tiers of council? Impossible!');
    }

    my ($lat, $lon) = mySociety::GeoUtil::national_grid_to_wgs84($e, $n, 'G');
    my $dist = mySociety::Gaze::get_radius_containing_population($lat, $lon, 200000);
    $dist = int($dist*10+0.5)/10;

    <<EOF;
<h1>Local RSS feeds and email alerts for &lsquo;$input_h{pc}&rsquo;</h1>

<p>We have a variety of RSS feeds for local problems. The easiest is our simple geographic one:</p>

<p id="rss_local"><a href="/rss/$x,$y"><img
src="/i/feed.png" width="16" height="16" title="RSS feed of recent local problems" alt="RSS feed" border="0"></a>
<a href="/rss/$x,$y">Problems within ${dist}km of this location</a> (a default
distance which covers roughly 200,000 people)
</p>
<p id="rss_local_alt">
(alternatively within <a href="/rss/$x,$y/2">2km</a> / <a href="/rss/$x,$y/5">5km</a>
/ <a href="/rss/$x,$y/10">10km</a> / <a href="/rss/$x,$y/20">20km</a>)
</ul>

<p>Or you can subscribe to a feed based upon what ward or council you&rsquo;re in. Simply
select which feed you&rsquo;d like and click the button. If you&rsquo;d prefer,
these feeds are also available as email alerts &ndash; just enter your email
address below.</p>

<form id="alerts" method="post" action="/alert">
<input type="hidden" name="type" value="local">
<input type="hidden" name="pc" value="$input_h{pc}">

$options

$errors

<p><input type="submit" name="rss" value="Give me an RSS feed"></p>

<p id="alert_or">or</p>

<p>Your email: <input type="text" id="email" name="email" value="$input_h{email}" size="30"></p>
<p><input type="submit" name="alert" value="Subscribe me to an email alert"></p>

</div>
</form>
EOF
}

sub alert_list_options {
    my $q = shift;
    my $out = '';
    my $feed = $q->param('feed') || '';
    foreach (@_) {
        my ($type, $vals, $rss, $text) = @$_;
        (my $vals2 = $rss) =~ tr{/+}{:_};
        my $id = $type . ':' . $vals . ':' . $vals2;
        $out .= '<li><input type="radio" name="feed" id="' . $id . '" ';
	$out .= 'checked ' if $feed eq $id;
        $out .= 'value="' . $id . '"> <label for="' . $id . '">' . $text
	    . '</label> <a href="/rss/';
        $out .= $type eq 'area' ? 'area' : 'reports';
        $out .= '/' . $rss . '"><img src="/i/feed.png" width="16" height="16"
title="RSS feed of recent local problems" alt="RSS feed" border="0"></a>';
    }
    return $out;
}

sub alert_front_page {
    my $q = shift;
    my $error = shift;
    my $errors = '';
    $errors = '<ul id="error"><li>' . $error . '</li></ul>' if $error;

    my %input_h = map { $_ => $q->param($_) ? ent($q->param($_)) : '' } qw(pc);
    my $out = <<EOF;
<h1>Local RSS feeds and email alerts</h1>
$errors
<form method="get" action="/alert">
<p>To find out what local alerts we have, please enter your UK postcode or street name here:
<input type="text" name="pc" value="$input_h{pc}">
<input type="submit" value="Look up">
</form>
EOF
    return $out;
}

sub alert_rss {
    my $q = shift;
    my $feed = $q->param('feed');
    return alert_list($q, 'Please select the feed you want') unless $feed;
    if ($feed =~ /^area:(?:\d+:)+(.*)$/) {
        (my $id = $1) =~ tr{:_}{/+};
        print $q->redirect('/rss/area/' . $id);
        return;
    } elsif ($feed =~ /^(?:council|ward):(?:\d+:)+(.*)$/) {
        (my $id = $1) =~ tr{:_}{/+};
        print $q->redirect('/rss/reports/' . $id);
        return;
    } else {
        return alert_list($q, 'Illegal feed selection');
    }
}

sub alert_updates_form {
    my ($q, @errors) = @_;
    my @vars = qw(id email);
    my %input = map { $_ => $q->param($_) || '' } @vars;
    my %input_h = map { $_ => $q->param($_) ? ent($q->param($_)) : '' } @vars;
    my $out = '';
    if (@errors) {
        $out .= '<ul id="error"><li>' . join('</li><li>', @errors) . '</li></ul>';
    }
    $out .= $q->p(_('Receive email when updates are left on this problem.'));
    my $label = _('Email:');
    my $subscribe = _('Subscribe');
    $out .= <<EOF;
<form action="alert" method="post">
<label class="n" for="alert_email">$label</label>
<input type="text" name="email" id="alert_email" value="$input_h{email}" size="30">
<input type="hidden" name="id" value="$input_h{id}">
<input type="hidden" name="type" value="updates">
<input type="submit" value="$subscribe">
</form>
EOF
    return $out;
}

sub alert_signed_input {
    my $q = shift;
    my ($salt, $signed_email) = split /,/, $q->param('signed_email');
    my $email = $q->param('email');
    my $id = $q->param('id');
    my $secret = scalar(dbh()->selectrow_array('select secret from secret'));
    my $out;
    if ($signed_email eq sha1_hex("$id-$email-$salt-$secret")) {
        my $alert_id = mySociety::Alert::create($email, 'new_updates', $id);
        mySociety::Alert::confirm($alert_id);
        $out = $q->p(_('You have successfully subscribed to that alert.'));
        $out .= CrossSell::display_advert($email);
    } else {
        $out = $q->p(_('We could not validate that alert.'));
    }
    return $out;
}

sub alert_token {
    my ($q, $data) = @_;
    my $id = $data->{id};
    my $type = $data->{type};
    my $email = $data->{email};
    my $out;
    if ($type eq 'subscribe') {
        mySociety::Alert::confirm($id);
        $out = $q->p(_('You have successfully confirmed your alert.'));
        $out .= CrossSell::display_advert($email);
    } elsif ($type eq 'unsubscribe') {
        mySociety::Alert::delete($id);
        $out = $q->p(_('You have successfully deleted your alert.'));
        $out .= CrossSell::display_advert($email);
    }
    return $out;
}

sub alert_do_subscribe {
    my ($q, $email) = @_;

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

    my @errors;
    push @errors, _('Please enter a valid email address') unless is_valid_email($email);
    push @errors, _('Please select the feed you want') if $type eq 'local' && !$q->param('feed');
    if (@errors) {
        return alert_updates_form($q, @errors) if $type eq 'updates';
        return alert_list($q, @errors) if $type eq 'local';
        return 'argh';
    }

    my $alert_id;
    if ($type eq 'updates') {
        my $id = $q->param('id');
        $alert_id = mySociety::Alert::create($email, 'new_updates', $id);
    } elsif ($type eq 'problems') {
        $alert_id = mySociety::Alert::create($email, 'new_problems');
    } elsif ($type eq 'local') {
        my $feed = $q->param('feed');
        if ($feed =~ /^area:(?:\d+:)?(\d+)/) {
	    $alert_id = mySociety::Alert::create($email, 'area_problems', $1);
        } elsif ($feed =~ /^council:(\d+)/) {
	    $alert_id = mySociety::Alert::create($email, 'council_problems', $1, $1);
        } elsif ($feed =~ /^ward:(\d+):(\d+)/) {
	    $alert_id = mySociety::Alert::create($email, 'ward_problems', $1, $2);
	}
    } else {
        throw mySociety::Alert::Error('Invalid type');
    }

    my %h = ();
    $h{url} = mySociety::Config::get('BASE_URL') . '/A/'
        . mySociety::AuthToken::store('alert', { id => $alert_id, type => 'subscribe', email => $email } );
    dbh()->commit();
    return Page::send_email($email, undef, 'alert', %h);
}