#!/usr/bin/perl
use Firework;

# add_rocket(initial_x, initial_y, v_x, v_y, start_time, color);

my $display=new Firework;
$display->add_rocket(0,25,18,18);
$display->add_rocket(25,25,18,18,7);
$display->add_wheel(19,22,3);
$display->add_wheel(60,22,8);

$display->start_display;
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package Firework;
use Firework::Rockets;
use Firework::Catherine;
### used for what the rockets look like:
use constant Point=>".";
#use constant Point=>"*";

use strict;

sub new {
my($self,$point)=@_;
my $display={fireworks=>[],Time=>0,Point=>$point||Point};

bless$display;
return$display;
}

sub add_rocket {
  my ($display,@args)=@_;
  my $firework=Firework::Rockets->new(@_);
  push@{$display->{fireworks}},$firework;
}

sub add_wheel {
  my($display,@args)=@_;
  my $wheel=Firework::Catherine->new(@_);
  push@{$display->{fireworks}},$wheel;
}


sub start_display {
  my $display=shift;
  my $live_fireworks=1;
  $|=1;

  while($live_fireworks){
  $live_fireworks=0;
  print "\ec";
  $display->{Time}+=1;
  foreach my $firework (@{$display->{fireworks}}){
   if(!$firework->{dead}){
   $live_fireworks++;

   if($firework->{exploded}){
        $firework->post_explode;

   } else {
     if($firework->should_explode ){
        $firework->explode;
     } else {

       if($display->{Time}>$firework->{start}){
        $firework->draw;
        $firework->{timer}+=.1;
       }
     }

  }

  }

  }
  select undef,undef,undef,0.1
  }
}

# and some defaults;
sub draw {
  my $firework=shift;
  if($firework->y_t > 0 && $firework->y_t < 25 && $firework->x_t > 0 &
+& $firework->x_t < 80){
  printf"\e[%d;%dH\e[1;%dm%s\e[m\e[H",$firework->y_t,
                                     $firework->x_t,
                                     $firework->{colour},
                                     $firework->{display}->{Point};
  }
}


sub x_t {
  my $firework=shift;
  return $firework->{i_x}+$firework->{v_x}*$firework->{timer};
}

sub y_t {
  my $firework=shift;
  # s=ut+1/2*a*t^2
  return $firework->{i_y} - $firework->{timer}*
                          ($firework->{v_y}-5*$firework->{timer});
}

sub v_y_t {
my $firework=shift;
return $firework->{v_y}-10*$firework->{timer}
}

sub explode {
my $firework=shift;
$firework->{dead}=1;
}

sub should_explode {
return 0;
}

1;
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package Firework::Rockets;
use Firework;
our @ISA=qw{ Firework };

sub new {
  my($self,$display,$i_x,$i_y,$v_x,$v_y,$start,$colour)=@_;
  my $firework={
        i_x=>$i_x,
        i_y=>$i_y,
        v_x=>$v_x,
        v_y=>$v_y,
        start=>$start,
        display=>$display,
        colour=>$colour||31+rand(6)
  };
  bless $firework,$self;
  return $firework;
}


sub explode {
my $firework=shift;
$firework->{exploded}=1;

for my $z (1..4){
$firework->{parts}{$z}=bless{
        i_x=>$firework->x_t,
        i_y=>$firework->y_t,
        v_x=>$z%2?5:-5,
        v_y=>$z>2?5:-5,
        colour=>$firework->{colour},
        display=>$firework->{display}
};

}

}

sub should_explode {
my $self=shift;
return ($self->v_y_t < 0);
}


sub post_explode {
   my $firework=shift;
   foreach my $part_count (keys %{$firework->{parts}}){
        my $part=$firework->{parts}{$part_count};
        if($part->y_t > 22 || $part->x_t > 75 || $part->x_t < 0){
        delete $firework->{parts}{$part_count}
        } else {
        $part->draw;
        $part->{timer}+=.1;
        }
     }

        $firework->{dead}=1 if(!scalar keys %{$firework->{parts}});

}

1;
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package Firework::Catherine;
use Firework;
our @ISA=qw{ Firework };

sub new {
my($self,$display,$x,$y,$start)=@_;
my $firework={
   pos=>[[-1,-1],[-1,0],[-1,1],[0,1],[1,1],[1,0],[1,-1],[0,-1]],
   x=>$x,
   y=>$y,
   start=>$start,
   display=>$display

};

bless $firework,$self;
return $firework;
}

sub draw {
my $wheel=shift;

if($wheel->{x}<40){
push@{$wheel->{pos}},shift@{$wheel->{pos}};
} else {
unshift@{$wheel->{pos}},pop@{$wheel->{pos}};
}

for(0..2){
printf"\e[%d;%dH\e[1;%dm.\e[m\e[H",$wheel->{y}+$wheel->{pos}[$_][0],
                        $wheel->{x}+$wheel->{pos}[$_][1],31+rand(6);

if($wheel->{pos}[$_][1]==-1 && $wheel->{pos}[$_][0]==1 && $wheel->{tim
+er}%2){
$wheel->{display}->add_rocket(
                $wheel->{x},
                $wheel->{y},
                $wheel->{x}>40?-18:18,15+rand(6)
);
}
}
}

sub should_explode {
my $wheel=shift;
$wheel->{dead}=1 if($wheel->{timer}>6);
return 0;
}

1;
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