1 files changed, 78 insertions, 0 deletions
diff --git a/lib/images.php b/lib/images.php
new file mode 100644
index 0000000..9ec0301
--- /dev/null
+++ b/lib/images.php
@@ -0,0 +1,78 @@
+<?php
+function resize_image(string $src_path, string $dst_path, int $max_width, int $max_height, bool $set_format = true, bool $stretch = false): int|null
+{
+    if ($src_path == "") {
+        return -2;
+    }
+
+    $image = getimagesize($src_path);
+
+    if ($image == false) {
+        return -1;
+    }
+
+    $format = $set_format ? ".webp" : "";
+
+    $width = $image[0];
+    $height = $image[1];
+    $ratio = min($max_width / $width, $max_height / $height);
+    $new_width = $stretch ? $max_width : (int) ($width * $ratio);
+    $new_height = $stretch ? $max_height : (int) ($height * $ratio);
+
+    $input_path = escapeshellarg($src_path);
+    $output_path = escapeshellarg("$dst_path$format");
+
+    $result_code = null;
+
+    exec(command: "magick convert $input_path -coalesce -resize {$new_width}x{$new_height}! -loop 0 $output_path", result_code: $result_code);
+
+    return $result_code;
+}
+
+function create_image_bundle(string $src_path, string $dst_path, int $max_width, int $max_height, bool $set_format = true, bool $stretch = false): int|null
+{
+    if (!is_dir($dst_path)) {
+        if (!mkdir($dst_path, 0777, true)) {
+            return -3;
+        }
+    }
+
+    if ($err = resize_image($src_path, "$dst_path/3x", $max_width, $max_height, $set_format, $stretch)) {
+        array_map("unlink", glob("$dst_path/*.*"));
+        rmdir($dst_path);
+        return $err;
+    }
+
+    if ($err = resize_image($src_path, "$dst_path/2x", round($max_width / 2), round($max_height / 2), $set_format, $stretch)) {
+        array_map("unlink", glob("$dst_path/*.*"));
+        rmdir($dst_path);
+        return $err;
+    }
+
+    if ($err = resize_image($src_path, "$dst_path/1x", round($max_width / 4), round($max_height / 4), $set_format, $stretch)) {
+        array_map("unlink", glob("$dst_path/*.*"));
+        rmdir($dst_path);
+        return $err;
+    }
+
+    return null;
+}
+
+function get_file_extension(string $path): string|null
+{
+    if ($file = getimagesize($path)) {
+        return image_type_to_extension(intval($file[2]), false);
+    }
+
+    return null;
+}
+
+function does_file_meet_requirements(string $path, int $max_width, int $max_height): array
+{
+    $file = getimagesize($path);
+    if (!$file) {
+        return [false, null];
+    }
+
+    return [$file[0] <= $max_width && $file[1] <= $max_height, image_type_to_extension(intval($file[2]), false)];
+}
+\ No newline at end of file