refactor(dav): simplify length header handling

Reduce nesting and drop duplicated sections.

Signed-off-by: Ferdinand Thiessen <opensource@fthiessen.de>

apps/dav/lib/Connector/Sabre/File.php

@@ -232,42 +232,36 @@ class File extends Node implements IFile {
 				fclose($target);
 			}
 
-			if ($result === false) {
-				$expected = -1;
-				$lengthHeader = $this->request->getHeader('content-length');
-				if ($lengthHeader) {
-					$expected = (int)$lengthHeader;
-				}
-				if ($expected !== 0) {
-					throw new Exception(
-						$this->l10n->t(
-							'Error while copying file to target location (copied: %1$s, expected filesize: %2$s)',
-							[
-								$this->l10n->n('%n byte', '%n bytes', $count),
-								$this->l10n->n('%n byte', '%n bytes', $expected),
-							],
-						)
-					);
-				}
+			$lengthHeader = $this->request->getHeader('content-length');
+			$expected = $lengthHeader !== '' ? (int)$lengthHeader : -1;
+			if ($result === false && $expected >= 0) {
+				throw new Exception(
+					$this->l10n->t(
+						'Error while copying file to target location (copied: %1$s, expected filesize: %2$s)',
+						[
+							$this->l10n->n('%n byte', '%n bytes', $count),
+							$this->l10n->n('%n byte', '%n bytes', $expected),
+						],
+					)
+				);
 			}
 
 			// if content length is sent by client:
 			// double check if the file was fully received
 			// compare expected and actual size
-			$lengthHeader = $this->request->getHeader('content-length');
-			if ($lengthHeader && $this->request->getMethod() === 'PUT') {
-				$expected = (int)$lengthHeader;
-				if ($count !== $expected) {
-					throw new BadRequest(
-						$this->l10n->t(
-							'Expected filesize of %1$s but read (from Nextcloud client) and wrote (to Nextcloud storage) %2$s. Could either be a network problem on the sending side or a problem writing to the storage on the server side.',
-							[
-								$this->l10n->n('%n byte', '%n bytes', $expected),
-								$this->l10n->n('%n byte', '%n bytes', $count),
-							],
-						)
-					);
-				}
+			if ($expected >= 0
+				&& $expected !== $count
+				&& $this->request->getMethod() === 'PUT'
+			) {
+				throw new BadRequest(
+					$this->l10n->t(
+						'Expected filesize of %1$s but read (from Nextcloud client) and wrote (to Nextcloud storage) %2$s. Could either be a network problem on the sending side or a problem writing to the storage on the server side.',
+						[
+							$this->l10n->n('%n byte', '%n bytes', $expected),
+							$this->l10n->n('%n byte', '%n bytes', $count),
+						],
+					)
+				);
 			}
 		} catch (\Exception $e) {
 			if ($e instanceof LockedException) {