1 files changed, 136 insertions, 0 deletions
diff --git a/workflow-designer-ui/src/main/frontend/src/features/version/composition/custom-modeler/custom/CustomRules.js b/workflow-designer-ui/src/main/frontend/src/features/version/composition/custom-modeler/custom/CustomRules.js
new file mode 100644
index 00000000..1dce143d
--- /dev/null
+++ b/workflow-designer-ui/src/main/frontend/src/features/version/composition/custom-modeler/custom/CustomRules.js
@@ -0,0 +1,136 @@
+import { reduce } from 'min-dash';
+
+import inherits from 'inherits';
+
+import { is } from 'bpmn-js/lib/util/ModelUtil';
+
+import RuleProvider from 'diagram-js/lib/features/rules/RuleProvider';
+
+var HIGH_PRIORITY = 1500;
+
+function isCustom(element) {
+    return element && /^custom:/.test(element.type);
+}
+
+/**
+ * Specific rules for custom elements
+ */
+export default function CustomRules(eventBus) {
+    RuleProvider.call(this, eventBus);
+}
+
+inherits(CustomRules, RuleProvider);
+
+CustomRules.$inject = ['eventBus'];
+
+CustomRules.prototype.init = function() {
+    /**
+     * Can shape be created on target container?
+     */
+    function canCreate(shape, target) {
+        // only judge about custom elements
+        if (!isCustom(shape)) {
+            return;
+        }
+
+        // allow creation on processes
+        return (
+            is(target, 'bpmn:Process') ||
+            is(target, 'bpmn:Participant') ||
+            is(target, 'bpmn:Collaboration')
+        );
+    }
+
+    /**
+     * Can source and target be connected?
+     */
+    function canConnect(source, target) {
+        // only judge about custom elements
+        if (!isCustom(source) && !isCustom(target)) {
+            return;
+        }
+
+        // allow connection between custom shape and task
+        if (isCustom(source)) {
+            if (is(target, 'bpmn:Task')) {
+                return { type: 'custom:connection' };
+            } else {
+                return false;
+            }
+        } else if (isCustom(target)) {
+            if (is(source, 'bpmn:Task')) {
+                return { type: 'custom:connection' };
+            } else {
+                return false;
+            }
+        }
+    }
+
+    this.addRule('elements.move', HIGH_PRIORITY, function(context) {
+        var target = context.target,
+            shapes = context.shapes;
+
+        var type;
+
+        // do not allow mixed movements of custom / BPMN shapes
+        // if any shape cannot be moved, the group cannot be moved, too
+        var allowed = reduce(
+            shapes,
+            function(result, s) {
+                if (type === undefined) {
+                    type = isCustom(s);
+                }
+
+                if (type !== isCustom(s) || result === false) {
+                    return false;
+                }
+
+                return canCreate(s, target);
+            },
+            undefined
+        );
+
+        // reject, if we have at least one
+        // custom element that cannot be moved
+        return allowed;
+    });
+
+    this.addRule('shape.create', HIGH_PRIORITY, function(context) {
+        var target = context.target,
+            shape = context.shape;
+
+        return canCreate(shape, target);
+    });
+
+    this.addRule('shape.resize', HIGH_PRIORITY, function(context) {
+        var shape = context.shape;
+
+        if (isCustom(shape)) {
+            // cannot resize custom elements
+            return false;
+        }
+    });
+
+    this.addRule('connection.create', HIGH_PRIORITY, function(context) {
+        var source = context.source,
+            target = context.target;
+
+        return canConnect(source, target);
+    });
+
+    this.addRule('connection.reconnectStart', HIGH_PRIORITY, function(context) {
+        var connection = context.connection,
+            source = context.hover || context.source,
+            target = connection.target;
+
+        return canConnect(source, target, connection);
+    });
+
+    this.addRule('connection.reconnectEnd', HIGH_PRIORITY, function(context) {
+        var connection = context.connection,
+            source = connection.source,
+            target = context.hover || context.target;
+
+        return canConnect(source, target, connection);
+    });
+};