Use the 'yy-mm-dd' format to pass the 'start' and 'end' date when instanciating an event class

Changes.md

@@ -1,5 +1,9 @@
 # Change Log
 
+### Improved
+
+- Use the 'yy-mm-dd' format to pass the 'start' and 'end' date when instanciating an event class
+
 ## [0.0.10] - 2022-06-14
 
 ### Fixed

lib/SVG/Timeline.pm

@@ -15,8 +15,8 @@ SVG::Timeline - Create SVG timeline charts
     });
 
     $tl->add_event({
-      start => 1939,
-      end   => 1945,
+      start => '1939-09-01', # 1 Sep 1939
+      end   => '1945-05-08', # 8 May 1945
       text  => 'World War II',
     });
 
@@ -263,6 +263,27 @@ sub events_in_timeline {
   return $_[0]->count_events;
 }
 
+=head2 add_event
+
+Takes a hash reference with event details and adds an L<SVG::Timeline::Event>
+to the timeline. The following details are supported:
+
+=over 4
+
+=item * text - the name of the event that is displayed on the bar. This is required.
+
+=item * start - the start year of the event. It is a string of format C<yy-mm-dd>.
+For example, C<2017-07-02> is the 2nd of July 2017. C<-mm-dd> as well as C<-dd> can
+be omitted.
+
+=item * end - the end year of the event, requirements are the same as that of C<start>.
+
+=item * colour - the colour that is used to fill the timeline block. This should be
+defined in the RGB format used by SVG. For example, red would be 'RGB(255,0,0)'.
+This is optional. If not provided, the C<default_color> is used.
+
+=back
+
 =head2 calculated_height
 
 The height of the timeline in "calculated units".
@@ -287,7 +308,7 @@ sub calculated_height {
 
 =head2 calculated_width
 
-The widtn in "calulated units".
+The width in "calulated units".
 
 =cut
 

lib/SVG/Timeline/Event.pm

@@ -14,11 +14,18 @@ use 5.010;
 
 use Moose;
 use Moose::Util::TypeConstraints;
+use DateTime;
 
 coerce __PACKAGE__,
   from 'HashRef',
   via  { __PACKAGE__->new($_) };
 
+# Choosen format: yy-mm-dd
+subtype 'Date',
+  as 'Str',
+  where   { m/ \d{4} (?: -\d{2} (?: -\d{2} )? )? /ax },
+  message { "Date format, '$_', is not valid"       };
+
 has index => (
   is => 'ro',
   isa => 'Int',
@@ -31,16 +38,30 @@ has text => (
   required => 1,
 );
 
+# Convert date to a floating year
+sub floating_year_of {
+    my ( $self, $date_str, $attr ) = @_;
+    my ( $year, $month, $day ) = split m/-/, $date_str;
+
+    $self->{$attr} = $year;
+    my $date  = DateTime->new( year => $year, month => $month // 1, day => $day // 1 );
+    my $ndays = $date->jd - $date->set( month => 1, day => 1 )->jd;
+
+    $self->{$attr} += $ndays / ( $date->is_leap_year ? 366 : 365 ) if $ndays > 0;
+}
+
 has start => (
   is => 'ro',
-  isa => 'Int',
+  isa => 'Date',
   required => 1,
+  trigger => sub { floating_year_of( @_[0..1], 'start' ) },
 );
 
 has end => (
   is => 'ro',
-  isa => 'Int',
+  isa => 'Date',
   required => 1,
+  trigger => sub { floating_year_of( @_[0..1], 'end' ) },
 );
 
 has colour => (

t/01-basic.t

@@ -8,12 +8,18 @@ use Time::Piece;
 my $tl = SVG::Timeline->new;
 
 $tl->add_event({
-  start => 1987,
-  end   => localtime->year,
+  start => '1987',
+  end   => '2022-10-23',
   text  => 'Perl',
 });
 
-is($tl->count_events, 1, 'Correct number of events');
+$tl->add_event({
+  start => '2017-07-29',
+  end   => '2022',
+  text  => 'SVG::Timeline on CPAN',
+});
+
+is($tl->count_events, 2, 'Correct number of events');
 is($tl->events->[0]->index, 1, 'Correct index for event');
 isa_ok($tl->svg, 'SVG');
 my $vb1 = $tl->svg->getChildren->[0]{viewBox};
@@ -23,7 +29,7 @@ $tl->add_event({
   end   => localtime->year,
   text  => 'Python',
 });
-is($tl->count_events, 2, 'Correct number of events');
+is($tl->count_events, 3, 'Correct number of events');
 
 my $vb2 = $tl->svg->getChildren->[0]{viewBox};
 isnt($vb1, $vb2, 'Viewbox changed');