From fb919fbb53e28940ecd9313428c9fcd6755953ae Mon Sep 17 00:00:00 2001
From: =?utf8?q?Tim=20D=C3=BCsterhus?= <duesterhus@woltlab.com>
Date: Tue, 30 Jun 2020 11:27:58 +0200
Subject: [PATCH] Add support for acceptable types to UploadFormField of form
 builder

Resolves #3414
---
 .../builder/field/UploadFormField.class.php   | 57 ++++++++++++++++++-
 1 file changed, 56 insertions(+), 1 deletion(-)

diff --git a/wcfsetup/install/files/lib/system/form/builder/field/UploadFormField.class.php b/wcfsetup/install/files/lib/system/form/builder/field/UploadFormField.class.php
index d095b32468..ec8239f4b9 100644
--- a/wcfsetup/install/files/lib/system/form/builder/field/UploadFormField.class.php
+++ b/wcfsetup/install/files/lib/system/form/builder/field/UploadFormField.class.php
@@ -42,6 +42,13 @@ class UploadFormField extends AbstractFormField {
 	 */
 	protected $allowSvgImage = false;
 	
+	/**
+	 * Acceptable file types.
+	 * @var null|string[]
+	 * @since 5.3
+	 */
+	protected $acceptableFiles = null;
+	
 	/**
 	 * maximum filesize for each uploaded file
 	 * @var	null|number
@@ -110,6 +117,7 @@ class UploadFormField extends AbstractFormField {
 		if ($this->isImageOnly()) {
 			$uploadField->setAllowSvgImage($this->svgImageAllowed());
 		}
+		$uploadField->setAcceptableFiles($this->getAcceptableFiles());
 		
 		return $uploadField;
 	}
@@ -597,7 +605,10 @@ class UploadFormField extends AbstractFormField {
 	/**
 	 * Sets the flag for `imageOnly`. This flag indicates whether only images 
 	 * can uploaded via this field. Other file types will be rejected during upload.
-	 *
+	 * 
+	 * If set to `true` will also set the acceptable types to `image/*`. If set to
+	 * false it will clear the acceptable types if they are `image/*`.
+	 * 
 	 * @param	boolean	        $imageOnly
 	 * @return	static				this field
 	 * 
@@ -623,6 +634,16 @@ class UploadFormField extends AbstractFormField {
 		}
 		
 		$this->imageOnly = $imageOnly;
+		if ($imageOnly) {
+			$this->setAcceptableFiles(['image/*']);
+		}
+		else {
+			// Using == here is safe, because we match a single element array containing
+			// a scalar value.
+			if ($this->getAcceptableFiles() == ['image/*']) {
+				$this->setAcceptableFiles(null);
+			}
+		}
 		
 		return $this;
 	}
@@ -668,4 +689,38 @@ class UploadFormField extends AbstractFormField {
 	public function svgImageAllowed() {
 		return $this->allowSvgImage;
 	}
+	
+	/**
+	 * Specifies acceptable file types. Use null to not specify any restrictions.
+	 * 
+	 * <strong>Heads up:</strong> This feature is used to improve user experience, by removing
+	 * unacceptable files from the file picker. It does not validate the type of the uploaded
+	 * file. You are responsible to perform (proper) validation on the server side.
+	 * 
+	 * Valid values are specified as "Unique file type specifiers":
+	 * - A case insensitive file extension starting with a dot.
+	 * - A mime type.
+	 * - `audio/*`
+	 * - `image/*`
+	 * - `video/*`
+	 * 
+	 * @see         https://developer.mozilla.org/en-US/docs/Web/HTML/Element/input/file#Unique_file_type_specifiers
+	 * @param       string[]|null     $acceptableFiles
+	 * @since       5.3
+	 */
+	public function setAcceptableFiles($acceptableFiles = null) {
+		$this->acceptableFiles = $acceptableFiles;
+		
+		return $this;
+	}
+	
+	/**
+	 * Returns the acceptable file types.
+	 * 
+	 * @return      string[]|null
+	 * @since       5.3
+	 */
+	public function getAcceptableFiles() {
+		return $this->acceptableFiles;
+	}
 }
-- 
2.20.1