#!/usr/bin/perl
use strict;
use warnings;

use Fancy::Join qw(join_defined); # this can be replaced with join('', defined()); for the $couple variable
use Util::Convert qw(idify);      # this can be removed from the make_ids sub

use SVG ();

# Note
## It appears the SVG module is not complete.
## When you see '->tag ', that means that tag was not exported by SVG.

sub make_ids {
  my $in = shift;
  ( my $no_space = $in) =~ s/\s//g;
  my $id = idify($no_space);
  return $id;
}

sub family_y {
  my ($gen, $num_parents) = @_;

  my $multiplier = $gen - 1;
  my $modifier   = $num_parents == 2 ? 0 : $num_parents == 1 ? 18 : 38;
  my $family_y = (-18 + (-76 * $multiplier)) + $modifier;

  return $family_y;
}

my $input = shift;
my $points = [ split(/; /, $input) ];

my $data;
for my $point (@$points) {
  my ($key, $value) = split(/\=/, $point);
  $data->{$key} = $value;
}

# Start the top of the svg

my $width  = 300;
my $height = 300;

my $svg = SVG->new( viewBox => "0 0 $width $height", width => $width, height => $height);

# Start the family groups

my $family   = $data->{family};
my $gen      = $data->{gen};
my $mother   = $data->{mother};
my $father   = $data->{father};
my $children = $data->{children};

if ( $gen == 1 && $children ) {
  die "Generation 1 families do not have children, you might want generation 2. tree-paths.pl died$!";
}
my $Yyy     = $mother ? substr $mother, 0, 3 : undef;
my $Xxx     = $father ? substr $father, 0, 3 : undef;

my $moth_id = $mother ? make_ids($mother) : undef;
my $fath_id = $father ? make_ids($father) : undef;

my $couple  = join_defined(' and ', ($mother, $father));

my $num_parents = ($mother && $father) ? 2 :
                  ($mother || $father) ? 1 :
                  0;

my $rel_id  = $num_parents == 2 ? "$Yyy$Xxx" :
              $mother ? $moth_id :
              $father ? $fath_id :
              $family ? $family :
              undef;

my $rel     = $data->{rel} // undef;
my $abb_rel = $rel ? substr $rel, 0, 1 : undef;

my $couple_id = "$abb_rel$rel_id";

my $child_list  = $children ? [ split(/, /, $children) ] : undef;
my $child_ids   = $children ? [ map { make_ids($_) } @$child_list ] : undef;
my $child_count = $children ? @$child_list : 0;

my $family_y = family_y($gen, $num_parents);

my $family_group;
my $child_group;

# Start the paths of relationship if both parents are known

if ( $num_parents == 2 ) {
  $family_group   = $svg->group( id => '', class => $rel, transform => "translate(79, $family_y)" );
  $family_group->tag('title')->cdata(ucfirst "$rel of $couple");
  $family_group->tag('path', d => 'm 0,0 h -19', id => "$couple_id-$moth_id");
  $family_group->tag('path', d => 'm 0,0 h  19', id => "$couple_id-$fath_id");
}

# End the paths of relationship if both parents are known
# Start the group for the children

if ( $child_count > 0 ) {
  my $id_prefix = $num_parents > 0 ? "c$rel_id" : "sib$rel_id";

  # Start section determining if children group stands alone.
  if ( $num_parents == 2 ) {
    $child_group = $family_group->group( id => "$family-children", class => 'child' );
  }
  else {
    $child_group = $svg->group( id => "$family-siblings", class => 'child', transform => "translate(30, $family_y)" );
  }

  # End section determining if children group stands alone.
  # Start paths for children
  # Start path for one child

  if ( $child_count == 1 ) {
    $child_group->tag('title')->cdata("$child_list->[0], child of $couple");
    $child_group->tag('path', d => 'm 0,0 v  58', id => "$couple_id-$child_ids->[0]");
  }

  # End path for one child
  # Start group for multiple children

  else {
    my $child_title = $num_parents > 0 ? "Children of $couple" : "$family siblings";

    my $base_h  = -40;
    my $start_h = $base_h + (( $#$child_ids - 1 ) * -40);

    $child_group->tag('title')->cdata($child_title);
    $child_group->tag('path', d => 'm 0,0  v  38', id => "$couple_id-$id_prefix") if $num_parents > 0;
    for my $num (0..$#$child_ids) {
      $child_group->tag('path', d => "m 0,38 h $start_h v 20", id => "$id_prefix-$child_ids->[$num]");
      $start_h += 80;
    }

    $child_group->tag('circle', cx => '0', cy => '38', r => "1.5", id => "$id_prefix");

  # End group for multiple children
  }
}

# End the group for the children
# Start the circle of relationship of parents if both are known
## This circle had to come last.
## It covers the converging ends of the paths between the parents and children.

if ( $num_parents == 2 ) {
  $family_group->tag('circle', cx => '0', cy => '0', r => "1.5", id => "$abb_rel$rel_id");
}

# End the circle of relationship of parents if both are known
# End the family groups

my $text = $num_parents == 2 ? $family_group->xmlify : $child_group->xmlify;
print "$text\n";