From 1925e80c4086f51c024986a55f004c1403f55ab7 Mon Sep 17 00:00:00 2001
From: Mischa POSLAWSKY <perl@shiar.org>
Date: Thu, 22 Jul 2021 18:31:49 +0200
Subject: [PATCH] word/edit: move code to download and convert images

Generalise into ImagePrep class to allow external (re)setup.
---
 Shiar_Sheet/ImagePrep.pm | 67 ++++++++++++++++++++++++++++++++++++++++
 writer.plp               | 58 ++++------------------------------
 2 files changed, 73 insertions(+), 52 deletions(-)
 create mode 100644 Shiar_Sheet/ImagePrep.pm

diff --git a/Shiar_Sheet/ImagePrep.pm b/Shiar_Sheet/ImagePrep.pm
new file mode 100644
index 0000000..699d224
--- /dev/null
+++ b/Shiar_Sheet/ImagePrep.pm
@@ -0,0 +1,67 @@
+package Shiar_Sheet::ImagePrep;
+
+use 5.014;
+use warnings;
+
+our $VERSION = '1.00';
+
+sub new {
+	my ($class, $target) = @_;
+	bless \$target, $class;
+}
+
+sub download {
+	# copy changed remote url to local file
+	my $target = shift;
+	unlink $$target if -e $$target;
+	my $download = shift or return 1;
+	require LWP::UserAgent;
+	my $ua = LWP::UserAgent->new;
+	$ua->agent('/');
+	my $status = $ua->mirror($download, $$target);
+	$status->is_success
+		or die "Download from <q>$download</q> failed: ".$status->status_line."\n";
+}
+
+sub convert {
+	my ($imgpath, $thumbpath, $cmds) = @_;
+	if (not -e $$imgpath) {
+		return unlink $thumbpath;
+	}
+
+	my $xyres = 0 ? '600x400' : '300x200'; # cover
+	my @cmds = @{ $cmds // [] };
+	if (my ($cmdarg) = grep { $cmds[$_] eq '-area' } 0 .. $#cmds) {
+		# replace option by permillage crop
+		my @dim = map { $_ / 1000 } split /\D/, $cmds[$cmdarg + 1];
+		splice @cmds, $cmdarg, 2, (
+			-set => 'option:distort:viewport' => sprintf(
+				'%%[fx:w*%s]x%%[fx:h*%s]+%%[fx:w*%s]+%%[fx:h*%s]',
+				($dim[2] || 1) - $dim[0], # width  = x2 - x1
+				($dim[3] || 1) - $dim[1], # height = y2 - y1
+				@dim[0, 1]                # offset = x1,y1
+			),
+			-distort => SRT => 0, # noop transform to apply viewport
+		);
+	}
+	@cmds = (
+		'convert',
+		$$imgpath,
+		-delete => '1--1', -background => 'white',
+		-gravity => defined $cmds ? 'northwest' : 'center',
+		@cmds,
+		-resize => "$xyres^", -extent => $xyres,
+		'-strip', -quality => '60%', -interlace => 'plane',
+		$thumbpath
+	);
+
+	require IPC::Run;
+	my $output;
+	IPC::Run::run(\@cmds, '<' => \undef, '>&' => \$output) or die [
+		"Failed to convert source image.",
+		"@cmds\n" .
+		($output || ($? & 127 ? "signal $?" : "error code ".($? >> 8))),
+	];
+}
+
+1;
diff --git a/writer.plp b/writer.plp
index b5f5032..fe538dd 100644
--- a/writer.plp
+++ b/writer.plp
@@ -188,67 +188,21 @@ elsif (defined $post{form}) {{
 		return 1;
 	} or Alert('Error creating translation entries', $@);
 
-	my $imgpath = $wordcol{source}->{-src}->($row);
+	require Shiar_Sheet::ImagePrep;
+	my $image = Shiar_Sheet::ImagePrep->new($wordcol{source}->{-src}->($row));
 	my $reimage = eval {
 		($row->{source} // '') ne ($replace->{source} // '') or return;
-		# copy changed remote url to local file
-		unlink $imgpath if -e $imgpath;
-		my $download = $row->{source} or return 1;
-		require LWP::UserAgent;
-		my $ua = LWP::UserAgent->new;
-		$ua->agent('/');
-		my $status = $ua->mirror($download, $imgpath);
-		$status->is_success
-			or die "Download from <q>$download</q> failed: ".$status->status_line."\n";
+		$image->download($row->{source});
 	};
 	!$@ or Alert(["Source image not found", $@]);
 
 	$reimage ||= $row->{thumb} ~~ $replace->{thumb};  # different convert
 	$reimage ||= $row->{cover} ~~ $replace->{cover};  # resize
 	$reimage++ if $fields{rethumb};  # force refresh
-
 	if ($reimage) {
-		my $thumbpath = $wordcol{thumb}->{-src}->($row);
-		if (-e $imgpath) {
-			my $xyres = $row->{cover} ? '600x400' : '300x200';
-			my @cmds = @{ $row->{thumb} // [] };
-			if (my ($cmdarg) = grep { $cmds[$_] eq '-area' } 0 .. $#cmds) {
-				# replace option by permillage crop
-				my @dim = map { $_ / 1000 } split /\D/, $cmds[$cmdarg + 1];
-				splice @cmds, $cmdarg, 2, (
-					-set => 'option:distort:viewport' => sprintf(
-						'%%[fx:w*%s]x%%[fx:h*%s]+%%[fx:w*%s]+%%[fx:h*%s]',
-						($dim[2] || 1) - $dim[0], # width  = x2 - x1
-						($dim[3] || 1) - $dim[1], # height = y2 - y1
-						@dim[0, 1]                # offset = x1,y1
-					),
-					-distort => SRT => 0, # noop transform to apply viewport
-				);
-			}
-			@cmds = (
-				'convert',
-				$imgpath,
-				-delete => '1--1', -background => 'white',
-				-gravity => defined $row->{thumb} ? 'northwest' : 'center',
-				@cmds,
-				-resize => "$xyres^", -extent => $xyres,
-				'-strip', -quality => '60%', -interlace => 'plane',
-				$thumbpath
-			);
-			eval {
-				require IPC::Run;
-				my $output;
-				IPC::Run::run(\@cmds, '<' => \undef, '>&' => \$output)
-					or die $output ||
-						($? & 127 ? "signal $?" : "error code ".($? >> 8))."\n";
-			} or Alert([
-				"Thumbnail image not generated",
-				"Failed to convert source image.",
-			], "@cmds\n$@");
-		}
-		else {
-			unlink $thumbpath;
-		}
+		eval {
+			$image->convert($wordcol{thumb}->{-src}->($row), $row->{thumb});
+		} or Alert([ "Thumbnail image not generated", $@->[0] ], $@->[1]);
 	}
 }}
 else {
-- 
2.30.0