From 259c6a2eb4c7a4924261ade4bbd261791c55c9fe Mon Sep 17 00:00:00 2001
From: Dmitry Karasik <dmitry@karasik.eu.org>
Date: Mon, 6 Nov 2023 16:13:29 +0100
Subject: [PATCH] handle loading errors gracefully

---
 Prima/Image/Animate.pm | 23 +++++++++++++++++++++-
 Prima/Image/Loader.pm  | 44 ++++++++++++++++++++++++++++++------------
 2 files changed, 54 insertions(+), 13 deletions(-)

diff --git a/Prima/Image/Animate.pm b/Prima/Image/Animate.pm
index c03b5f611..d413069a0 100644
--- a/Prima/Image/Animate.pm
+++ b/Prima/Image/Animate.pm
@@ -176,11 +176,21 @@ sub reset
 	$self-> fixup_rect( $e, $ix);
 }
 
+sub warning { shift->{warning} }
+
 sub load_next_image
 {
 	my $self = shift;
 	return unless $self->{loader};
-	my ( $i ) = $self->{loader}->next;
+	$self->{warning} = undef;
+	my ( $i, $err ) = $self->{loader}->next;
+	unless ($i) {
+		$self->{warning} = $err;
+		$self->{loader}->reload;
+		( $i, $err ) = $self->{loader}->next;
+		$self->{current} = 0;
+		$self->{warning} = $err unless $i;
+	}
 	return $i;
 }
 
@@ -209,6 +219,10 @@ sub advance_frame
 	} else {
 		$self->{image} = $oimg;
 	}
+	unless ($self->{image}) {
+		$self->{image} = $oimg;
+		$self->{info} = $oinfo;
+	}
  
 	my $info = $self->{info} = $self-> get_extras;
 	$self-> fixup_rect( $info, $self-> {image});
@@ -758,6 +772,13 @@ Returns the width and height of the composite frame
 
 Return the number of frames
 
+=head2 warning
+
+If an error occured during frame loading, it will be stored in the C<warning>
+property. The animation will stop at the last successfully loaded frame
+
+Only available if the C<loadAll> option is off.
+
 =head2 width
 
 Returns the width of the composite frame
diff --git a/Prima/Image/Loader.pm b/Prima/Image/Loader.pm
index bbe818f78..29daea246 100644
--- a/Prima/Image/Loader.pm
+++ b/Prima/Image/Loader.pm
@@ -15,11 +15,25 @@ sub new
 		$events{$k} = $v if $k =~ /^on/;
 	}
 
-	my $img = Prima::Image->new( %events );
-	my $ok = $img->load( $source,
+	my $self = bless {
+		source  => $source,
+		events  => \%events,
+		options => \%opt,
+	};
+
+	my ( $l, $ok ) = $self->reload;
+	return (undef, $ok) unless $l;
+	return $self;
+}
+
+sub reload
+{
+	my $self = shift;
+	my $img = Prima::Image->new( %{ $self->{events} } );
+	my $ok = $img->load( $self->{source},
 		loadExtras => 1,
 		wantFrames => 1,
-		%opt,
+		%{ $self->{options} },
 		session    => 1
 	);
 	unless ($ok) {
@@ -30,15 +44,12 @@ sub new
 		$img->destroy;
 		return (undef, "cannot read number of frames");
 	}
-
-	return bless {
-		source  => $source,
-		image   => $img,
-		extras  => $img->{extras},
-		frames  => $img->{extras}->{frames},
-		current => 0,
-		events  => \%events,
-	}, $class;
+	$self->{image}  = $img;
+	$self->{extras} = $img->{extras};
+	$self->{frames} = $img->{extras}->{frames};
+	$self->{current} = 0;
+	undef $self->{error};
+	return $img;
 }
 
 sub next
@@ -196,6 +207,15 @@ Loads the next image frame.
 
 Returns either a newly loaded image, or C<undef> and the error string.
 
+=item reload
+
+In case an animation file is defect, and cannot be loaded in full, the toolkit
+will not allow to continue the loading session and will close it automatically.
+If it is desired to work around this limitation, a new session must be opened.
+The C<reload> method does this by reopening the loading session with all the
+parameters supplied to C<new>. The programmer thus has a chance to record how
+many successful frames were loaded, and only navigate these after the reload.
+
 =item source
 
 Return the filename or the file handle passed to the C<new> call.