test(signature-text): add regression for invalid dimensions rejection

Add 24 data-provider entries covering zero, negative, fractional,
subnormal, scientific, NaN and Inf values as both width-only,
height-only and combined inputs.

Add testGetFullSignatureDimensionsShouldFallbackToDefaultsWhenConfigIsInvalid
covering stored 0, -1, NaN and Inf configs triggering auto-repair.

Signed-off-by: Vitor Mattos <1079143+vitormattos@users.noreply.github.com>

Author: vitormattos

tests/php/Unit/Service/SignatureTextServiceTest.php

@@ -11,6 +11,7 @@
 
 use Imagick;
 use OCA\Libresign\AppInfo\Application;
+use OCA\Libresign\Exception\LibresignException;
 use OCA\Libresign\Service\SignatureTextService;
 use OCP\IAppConfig;
 use OCP\IDateTimeZone;
@@ -218,4 +219,60 @@ public static function providerSignerNameImage(): array {
 	public function testHasFont(): void {
 		$this->assertFileExists($fallbackFond = __DIR__ . '/../../../../3rdparty/composer/mpdf/mpdf/ttfonts/DejaVuSerifCondensed.ttf');
 	}
+
+	#[DataProvider('providerInvalidSignatureDimensions')]
+	public function testSaveShouldRejectInvalidSignatureDimensions(float $signatureWidth, float $signatureHeight): void {
+		$this->expectException(LibresignException::class);
+
+		$this->getClass()->save(
+			template: 'valid',
+			signatureWidth: $signatureWidth,
+			signatureHeight: $signatureHeight,
+		);
+	}
+
+	public static function providerInvalidSignatureDimensions(): array {
+		return [
+			'zero width' => [0.0, 100.0],
+			'fractional width below minimum' => [0.9999, 100.0],
+			'subnormal width' => [1.0E-320, 100.0],
+			'scientific width below minimum' => [1.0E-6, 100.0],
+			'negative width' => [-1.0, 100.0],
+			'very small negative width' => [-0.0001, 100.0],
+			'NaN width' => [NAN, 100.0],
+			'INF width' => [INF, 100.0],
+			'-INF width' => [-INF, 100.0],
+			'zero height' => [350.0, 0.0],
+			'fractional height below minimum' => [350.0, 0.9999],
+			'subnormal height' => [350.0, 1.0E-320],
+			'scientific height below minimum' => [350.0, 1.0E-6],
+			'negative height' => [350.0, -1.0],
+			'very small negative height' => [350.0, -0.0001],
+			'NaN height' => [350.0, NAN],
+			'INF height' => [350.0, INF],
+			'-INF height' => [350.0, -INF],
+			'both dimensions zero' => [0.0, 0.0],
+			'both dimensions negative' => [-1.0, -1.0],
+			'both dimensions fractional below minimum' => [0.5, 0.5],
+			'both dimensions NaN' => [NAN, NAN],
+			'both dimensions INF' => [INF, INF],
+			'mixed NaN and -INF' => [NAN, -INF],
+		];
+	}
+
+	public function testGetFullSignatureDimensionsShouldFallbackToDefaultsWhenConfigIsInvalid(): void {
+		$this->appConfig->setValueFloat(Application::APP_ID, 'signature_width', 0.0);
+		$this->appConfig->setValueFloat(Application::APP_ID, 'signature_height', -1.0);
+
+		$class = $this->getClass();
+
+		$this->assertEquals(SignatureTextService::DEFAULT_SIGNATURE_WIDTH, $class->getFullSignatureWidth());
+		$this->assertEquals(SignatureTextService::DEFAULT_SIGNATURE_HEIGHT, $class->getFullSignatureHeight());
+
+		$this->appConfig->setValueFloat(Application::APP_ID, 'signature_width', NAN);
+		$this->appConfig->setValueFloat(Application::APP_ID, 'signature_height', INF);
+
+		$this->assertEquals(SignatureTextService::DEFAULT_SIGNATURE_WIDTH, $class->getFullSignatureWidth());
+		$this->assertEquals(SignatureTextService::DEFAULT_SIGNATURE_HEIGHT, $class->getFullSignatureHeight());
+	}
 }