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

my $site = 'http://www.fourmilab.ch/yoursky/cities.html';
my $mech = 'WWW::Mechanize::GZip'->new;
$mech->get($site);
$mech->follow_link( text => 'Portland OR' );
my $before_bound = 2457496.65;    #before conjunction
my $after_bound  = 2457496.75;    #after conjunction
$mech->set_fields(qw'date 2');
my $moonstring = 5;
my $jstr       = 3;
my $upper      = $before_bound;
my $lower      = $after_bound;
my $equal;
my $equal_sec;
my $now_string = localtime;
my $filename   = 'planet7.txt';
open( my $jh, '>>', $filename ) or die "Could not open file '$filename' $!";
say $jh "Script executed at $now_string";
my $attempts = 1;

while ( ( $jstr != $moonstring ) ) {

   my $default = ( ( $attempts >= MAXTRIES ) ) ? 'N' : 'Y';
   my $answer = prompt( "Make query number $attempts?", $default, TIMEOUT );
   exit if $answer =~ /^N/i;
   say "upper is $upper";
   say "lower is $lower";
   my $guess = closetohalf( $upper, $lower );
   say "guess is $guess";
   $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 $venus      = $table_tree->cell( 5, 1 )->as_text;
   my $jupiter    = $table_tree->cell( 7, 1 )->as_text;
   $moonstring = string_to_second($venus);
   say "moon seconds is $moonstring";
   $jstr = string_to_second($jupiter);
   say "jupiter seconds is $jstr";

   if ( $jstr > $moonstring ) {
      $upper = $guess;
   }
   elsif ( $moonstring > $jstr ) {
      $lower = $guess;
   }
   else {
      $equal = $guess;
      say "equal, while condition should fail $equal";
      $equal_sec = $moonstring;
   }
   $te->delete;
   $attempts++;
}

say $jh "equal seconds is $equal_sec";

###redesign 4/20/16
## determining beginning
my $outer = $before_bound;
my $inner = $equal;
say $jh join "\t", 'moonstring', 'jstr', 'outer', 'inner', 'guess';
$attempts = 1;
while ( ( abs( $outer - $inner ) > .00001 ) ) {

   my $default = ( ( $attempts >= MAXTRIES ) ) ? 'N' : 'Y';
   my $answer = prompt( "Make query number $attempts?", $default, TIMEOUT );
   exit if $answer =~ /^N/i;
   say "outer is $outer";
   say "inner is $inner";
   my $guess = closetohalf( $outer, $inner );
   say "guess is $guess";
   $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 $venus      = $table_tree->cell( 5, 1 )->as_text;
   my $jupiter    = $table_tree->cell( 7, 1 )->as_text;
   $moonstring = string_to_second($venus);
   $jstr       = string_to_second($jupiter);
   say $jh join "\t", $moonstring, $jstr, $outer, $inner, $guess;

   if ( $moonstring < $jstr ) {
      $outer = $guess;
   }
   elsif ( $moonstring == $jstr ) {
      $inner = $guess;
   }
   else {
      die "retrograde motion or bad data";
   }
   $te->delete;
   $attempts++;
}
say $jh "after beginning contraction, upper is $outer";
say $jh "after beginning contraction, lower is $inner";
my $begin_time = $inner;

## determine end time
$outer = $after_bound;
$inner = $equal;
say $jh join "\t", 'moonstring', 'jstr', 'outer', 'inner', 'guess';
$attempts = 1;
while ( ( abs( $outer - $inner ) > .00001 ) ) {

   my $default = ( ( $attempts >= MAXTRIES ) ) ? 'N' : 'Y';
   my $answer = prompt( "Make query number $attempts?", $default, TIMEOUT );
   exit if $answer =~ /^N/i;
   say "outer is $outer";
   say "inner is $inner";
   my $guess = closetohalf( $outer, $inner );
   say "guess is $guess";
   $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 $venus      = $table_tree->cell( 5, 1 )->as_text;
   my $jupiter    = $table_tree->cell( 7, 1 )->as_text;
   $moonstring = string_to_second($venus);
   $jstr       = string_to_second($jupiter);
   say $jh join "\t", $moonstring, $jstr, $outer, $inner, $guess;
   if ( $moonstring > $jstr ) {
      $outer = $guess;
   }
   elsif ( $moonstring == $jstr ) {
      $inner = $guess;
   }
   else {
      die "retrograde motion or bad data";
   }
   $te->delete;
   $attempts++;
}

say $jh "after ending contraction, outer is $outer";
say $jh "after ending contraction, inner is $inner";
my $end_time      = $inner;
my $jul_length    = $end_time - $begin_time;
my $second_length = $jul_length * 86400;
say "duration in seconds is $second_length";
say $jh "duration in seconds is $second_length";

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 {
      say "string was misformed";
   }
   return $return;
}

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


##</code><code>##

Script executed at Sun Apr 24 16:40:08 2016
equal seconds is 39783
moonstring	jstr	outer	inner	guess
39726	39783	2457496.65	2457496.69915925	2457496.67869833
39753	39783	2457496.67869833	2457496.69915925	2457496.68853017
39769	39783	2457496.68853017	2457496.69915925	2457496.69420768
39777	39783	2457496.69420768	2457496.69915925	2457496.69716155
39780	39783	2457496.69716155	2457496.69915925	2457496.69811072
39781	39783	2457496.69811072	2457496.69915925	2457496.69867181
39782	39783	2457496.69867181	2457496.69915925	2457496.69891007
39782	39783	2457496.69891007	2457496.69915925	2457496.69902581
39783	39783	2457496.69902581	2457496.69915925	2457496.69908113
39782	39783	2457496.69902581	2457496.69908113	2457496.69905188
39783	39783	2457496.69905188	2457496.69908113	2457496.69906548
39782	39783	2457496.69905188	2457496.69906548	2457496.69905783
after beginning contraction, upper is 2457496.69905783
after beginning contraction, lower is 2457496.69906548
moonstring	jstr	outer	inner	guess
39864	39783	2457496.75	2457496.69915925	2457496.72857204
39818	39783	2457496.72857204	2457496.69915925	2457496.71175627
39800	39783	2457496.71175627	2457496.69915925	2457496.70555956
39792	39783	2457496.70555956	2457496.69915925	2457496.70238023
39788	39783	2457496.70238023	2457496.69915925	2457496.70092664
39785	39783	2457496.70092664	2457496.69915925	2457496.6998935
39784	39783	2457496.6998935	2457496.69915925	2457496.69946611
39783	39783	2457496.69946611	2457496.69915925	2457496.69930239
39783	39783	2457496.69946611	2457496.69930239	2457496.69937787
39783	39783	2457496.69946611	2457496.69937787	2457496.69941601
39784	39783	2457496.69946611	2457496.69941601	2457496.69943739
39784	39783	2457496.69943739	2457496.69941601	2457496.69942669
39783	39783	2457496.69942669	2457496.69941601	2457496.699421
after ending contraction, outer is 2457496.69942669
after ending contraction, inner is 2457496.699421
duration in seconds is 30.7171538472176