Support for class properties (#283)

CHANGELOG.md

@@ -9,6 +9,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Added
 - Add `text`, `width` and `height` members to `ObjectShape::Text`. (#278)
 - Implement `ResourceReader` for appropiate functions. (#272) **Read the README's FAQ for more information about this change.**
+- Support for custom type properties. (#283)
 
 ## Fixed
 - `ObjectShape::Text::kerning`'s default value, which should have been set to `true` instead of `false`. (#278)

assets/tiled_class_property.tmx

@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<map version="1.10" tiledversion="1.10.2" orientation="orthogonal" renderorder="right-down" width="2" height="2" tilewidth="32" tileheight="32" infinite="0" nextlayerid="3" nextobjectid="4">
+ <layer id="1" name="Tile Layer 1" width="2" height="2">
+  <data encoding="csv">
+0,0,
+0,0
+</data>
+ </layer>
+ <objectgroup id="2" name="Object Layer 1">
+  <object id="2" x="0" y="0" width="32" height="32">
+   <properties>
+    <property name="class property" type="class" propertytype="test_type">
+     <properties>
+      <property name="test_property_1" type="int" value="3"/>
+     </properties>
+    </property>
+    <property name="empty property" type="class" propertytype="empty_type"/>
+   </properties>
+  </object>
+ </objectgroup>
+</map>

src/properties.rs

@@ -82,6 +82,14 @@ pub enum PropertyValue {
     /// An object ID value. Corresponds to the `object` property type.
     /// Holds the id of a referenced object, or 0 if unset.
     ObjectValue(u32),
+    /// A class value. Corresponds to the `class` property type.
+    /// Holds the type name and a set of properties.
+    ClassValue {
+        /// The type name.
+        property_type: String,
+        /// A set of properties.
+        properties: Properties,
+    },
 }
 
 impl PropertyValue {
@@ -135,15 +143,31 @@ pub(crate) fn parse_properties(
     let mut p = HashMap::new();
     parse_tag!(parser, "properties", {
         "property" => |attrs:Vec<OwnedAttribute>| {
-            let (t, v_attr, k) = get_attrs!(
+            let (t, v_attr, k, p_t) = get_attrs!(
                 for attr in attrs {
                     Some("type") => obj_type = attr,
                     Some("value") => value = attr,
+                    Some("propertytype") => propertytype = attr,
                     "name" => name = attr
                 }
-                (obj_type, value, name)
+                (obj_type, value, name, propertytype)
             );
             let t = t.unwrap_or_else(|| "string".to_owned());
+            if t == "class" {
+                // Class properties will have their member values stored in a nested <properties>
+                // element. Only the actually set members are saved. When no members have been set
+                // the properties element is left out entirely.
+                let properties = if has_properties_tag_next(parser) {
+                    parse_properties(parser)?
+                } else {
+                    HashMap::new()
+                };
+                p.insert(k, PropertyValue::ClassValue {
+                    property_type: p_t.unwrap_or_default(),
+                    properties,
+                });
+                return Ok(());
+            }
 
             let v: String = match v_attr {
                 Some(val) => val,
@@ -164,3 +188,26 @@ pub(crate) fn parse_properties(
     });
     Ok(p)
 }
+
+/// Checks if there is a properties tag next in the parser. Will consume any whitespace or comments.
+fn has_properties_tag_next(parser: &mut impl Iterator<Item = XmlEventResult>) -> bool {
+    let mut peekable = parser.by_ref().peekable();
+    while let Some(Ok(next)) = peekable.peek() {
+        match next {
+            XmlEvent::StartElement { name, .. } if name.local_name == "properties" => return true,
+            // Ignore whitespace and comments
+            XmlEvent::Whitespace(_) => {
+                peekable.next();
+            }
+            XmlEvent::Comment(_) => {
+                peekable.next();
+            }
+            // If we encounter anything else than whitespace, comments or the properties tag, we
+            // assume there are no properties.
+            _ => {
+                return false;
+            }
+        }
+    }
+    false
+}

tests/lib.rs

@@ -220,6 +220,7 @@ fn test_object_group_property() {
     };
     assert!(prop_value);
 }
+
 #[test]
 fn test_tileset_property() {
     let r = Loader::new()
@@ -325,6 +326,33 @@ fn test_object_property() {
     assert_eq!(3, prop_value);
 }
 
+#[test]
+fn test_class_property() {
+    let r = Loader::new()
+        .load_tmx_map("assets/tiled_class_property.tmx")
+        .unwrap();
+    let layer = r.get_layer(1).unwrap();
+    if let Some(PropertyValue::ClassValue {
+        property_type,
+        properties,
+    }) = layer
+        .as_object_layer()
+        .unwrap()
+        .get_object(0)
+        .unwrap()
+        .properties
+        .get("class property")
+    {
+        assert_eq!(property_type, "test_type");
+        assert_eq!(
+            properties.get("test_property_1").unwrap(),
+            &PropertyValue::IntValue(3)
+        );
+    } else {
+        panic!("Expected class property");
+    };
+}
+
 #[test]
 fn test_tint_color() {
     let r = Loader::new()
@@ -336,7 +364,7 @@ fn test_tint_color() {
             alpha: 0x12,
             red: 0x34,
             green: 0x56,
-            blue: 0x78
+            blue: 0x78,
         })
     );
     assert_eq!(
@@ -345,7 +373,7 @@ fn test_tint_color() {
             alpha: 0xFF,
             red: 0x12,
             green: 0x34,
-            blue: 0x56
+            blue: 0x56,
         })
     );
 }
@@ -370,7 +398,7 @@ fn test_group_layers() {
             alpha: 0x12,
             red: 0x34,
             green: 0x56,
-            blue: 0x78
+            blue: 0x78,
         })),
         layer_group_1.properties.get("key")
     );
@@ -417,7 +445,7 @@ fn test_object_template_property() {
         object.shape,
         ObjectShape::Rect {
             width: 32.0,
-            height: 32.0
+            height: 32.0,
         }
     );
     assert_eq!(object.x, 32.0);