2020/12/11 00:28:28 INFO ./4.wm_fermi.pl 
2020/12/11 00:28:33 INFO right ascension of jupiter 20h 11m 7s 
2020/12/11 00:28:33 INFO right ascension of saturn 20h 11m 3s 
2020/12/11 00:28:33 INFO jup seconds is 72667 
2020/12/11 00:28:33 INFO sat seconds is 72663 
2020/12/11 00:28:38 INFO right ascension of jupiter 20h 10m 16s 
2020/12/11 00:28:38 INFO right ascension of saturn 20h 10m 38s 
2020/12/11 00:28:38 INFO jup seconds is 72616 
2020/12/11 00:28:38 INFO sat seconds is 72638 
2020/12/11 00:28:42 INFO right ascension of jupiter 20h 10m 38s 
2020/12/11 00:28:42 INFO right ascension of saturn 20h 10m 49s 
2020/12/11 00:28:42 INFO jup seconds is 72638 
2020/12/11 00:28:42 INFO sat seconds is 72649 
2020/12/11 00:28:47 INFO right ascension of jupiter 20h 10m 53s 
2020/12/11 00:28:47 INFO right ascension of saturn 20h 10m 56s 
2020/12/11 00:28:47 INFO jup seconds is 72653 
2020/12/11 00:28:47 INFO sat seconds is 72656 
2020/12/11 00:28:51 INFO right ascension of jupiter 20h 11m 0s 
2020/12/11 00:28:51 INFO right ascension of saturn 20h 11m 0s 
2020/12/11 00:28:51 INFO jup seconds is 72660 
2020/12/11 00:28:51 INFO sat seconds is 72660 
2020/12/11 00:28:51 INFO equal, while condition fails at julian day 2459205.07717792 
2020/12/11 00:28:51 INFO equal seconds is 72660 
##</code><code>##

#!/usr/bin/env perl
use warnings;
use strict;
use 5.010;
use WWW::Mechanize;
use HTML::TableExtract qw(tree);
use open ':std', OUT => ':utf8';
use Prompt::Timeout;
use constant TIMEOUT  => 3;
use constant MAXTRIES => 30;
use Log::Log4perl;

## redesign for jupiter/saturn conjunction 2020

my $log_conf3 = "/home/hogan/Documents/hogan/logs/conf_files/3.conf";
my $log_conf4 = "/home/hogan/Documents/hogan/logs/conf_files/4.conf";

#Log::Log4perl::init($log_conf3); #debug
Log::Log4perl::init($log_conf4);    #info
my $logger = Log::Log4perl->get_logger();
$logger->info($0);

my $site = 'http://www.fourmilab.ch/yoursky/cities.html';
my $mech = WWW::Mechanize->new;
$mech->get($site);
$mech->follow_link( text => 'Portland OR' );
my $before_bound = 2459203.5;       #before conjunction
my $after_bound  = 2459206.5;       #after conjunction
$mech->set_fields(qw'date 2');
my ( $moon_seconds, $sun_seconds ) =
  ( 5, 3 );                         # unequal values to start script chugging
my $upper = $after_bound;
my $lower = $before_bound;

my ( $equal, $equal_sec );

my $attempts = 1;

while ( ( $sun_seconds != $moon_seconds ) ) {

  my $default = ( ( $attempts >= MAXTRIES ) ) ? 'N' : 'Y';
  my $answer  = prompt( "Make query number $attempts?", $default, TIMEOUT );
  exit if $answer =~ /^N/i;

  my $guess = closetohalf( $upper, $lower );

  $mech->set_fields( jd => $guess );
  $mech->click_button( value => "Update" );
  my $te = 'HTML::TableExtract'->new;
  $te->parse( $mech->content );
  my $table      = ( $te->tables )[3];
  my $table_tree = $table->tree;
  my $moon       = $table_tree->cell( 7, 1 )->as_text;
  $logger->info("right ascension of jupiter $moon");
  my $sun = $table_tree->cell( 8, 1 )->as_text;
  $logger->info("right ascension of saturn $sun");
  $moon_seconds = string_to_second($moon);
  $logger->info("jup seconds is $moon_seconds");
  $sun_seconds = string_to_second($sun);
  $logger->info("sat seconds is $sun_seconds");

  if ( $sun_seconds < $moon_seconds ) {
    $upper = $guess;
  }
  elsif ( $moon_seconds < $sun_seconds ) {
    $lower = $guess;
  }
  else {
    $equal = $guess;
    $logger->info("equal, while condition fails at julian day $equal");
    $equal_sec = $moon_seconds;
  }
  $te->delete;
  $attempts++;
}

$logger->info("equal seconds is $equal_sec");

sub string_to_second {
  my $string = shift;
  my $return = 9000;
  if ( my $success = $string =~ /^(\d*)h\s+(\d*)m\s+(\d*)s$/ ) {
    $return = 3600 * $1 + 60 * $2 + $3;
  }
  else {

    # log the error
    $logger->error("string was misformed $string");

    die "string was misformed $!";
  }
  return $return;
}

sub closetohalf {
  my ( $up, $low ) = @_;
  $low + ( $up - $low ) * ( 0.4 + rand 0.2 );
}

##</code><code>##

fred@fourth:~/mojo$ ls
1.button.pl  2.1.mojo_hello.pl  5.3.elev.debug.pl
1.myapp.pl   5.2.elev.pl        5.3.elev.pl
fred@fourth:~/mojo$