Add watching to resources folder

orx-olive/src/main/kotlin/Olive.kt

@@ -18,7 +18,7 @@ private fun <T> Event<T>.restoreListeners(store: Map<Event<*>, List<(Any) -> Uni
     listeners.retainAll(store[this] ?: emptyList<T>())
 }
 
-class Olive<P : Program> : Extension {
+class Olive<P : Program>(val resources: Resources? = null) : Extension {
     override var enabled: Boolean = true
     var session: Session? = null
 
@@ -110,5 +110,26 @@ class Olive<P : Program> : Extension {
         }
         setupScript(script)
         scriptChange = ::setupScript
+
+        if (resources != null) {
+            val srcPath = "src/main/resources"
+            var src = File(srcPath)
+
+            resources.watch(src) { file ->
+                val dest = "build/resources/main"
+                val filePath = file.path.split(Regex(srcPath), 2).getOrNull(1)
+
+                val destFile = File("$dest/${filePath}").absoluteFile
+
+                program.watchFile(file) {
+                    if (resources[file]!! && filePath != null) {
+                        file.copyTo(destFile, overwrite = true)
+                        reload()
+                    } else {
+                        resources[file] = true
+                    }
+                }
+            }
+        }
     }
 }

orx-olive/src/main/kotlin/Resources.kt

@@ -0,0 +1,29 @@
+package org.openrndr.extra.olive
+
+import java.io.File
+
+class Resources(val filterOutExtensions: List<String> = listOf()) {
+    private val watchedResources = mutableMapOf<File, Boolean>()
+
+    fun watch(src: File, watchFn: (file: File) -> Unit) {
+        src.listFiles()!!.forEach {file ->
+            if (file.isFile && !filterOutExtensions.contains(file.extension)) {
+                watchedResources[file] = false
+
+                watchFn(file)
+            } else if (file.isDirectory) {
+                watch(file, watchFn)
+            }
+        }
+    }
+
+    operator fun get(file: File): Boolean? {
+        return watchedResources[file]
+    }
+
+    operator fun set(file: File, value: Boolean) {
+        if (watchedResources.containsKey(file)) {
+            watchedResources[file] = value
+        }
+    }
+}