/*
 * Copyright (C) 2013-2015 RoboVM AB
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.robovm.objc;

import static org.junit.Assert.*;

import org.junit.Assume;
import org.junit.Before;
import org.junit.Test;
import org.robovm.apple.corefoundation.CFString;
import org.robovm.apple.foundation.NSCache;
import org.robovm.apple.foundation.NSCacheDelegate;
import org.robovm.apple.foundation.NSObject;
import org.robovm.apple.uikit.UIView;
import org.robovm.rt.bro.Bro;

public class ObjCObjectOwnershipHelperTest {

    class CustomNSObject extends NSObject {
        String stringValue;
        long longValue;

        public CustomNSObject(String stringValue, long longValue) {
            this.stringValue = stringValue;
            this.longValue = longValue;
        }
    }

    class CustomUIView extends UIView {}

    class CustomNSCacheDelegateAdapter extends NSObject implements NSCacheDelegate {
        @Override
        public void willEvictObject(NSCache cache, NSObject obj) {

        }
    }

    class CustomCFString extends CFString {
        public CustomCFString(String str) {
            super(str);
        }
    }

    @Before
    public void setUp() {
        Assume.assumeTrue(Bro.IS_DARWIN);
    }

    /**
     * Every custom class extending from NSObject should be retained on the Java
     * side when retained on the Obj-C side.
     */
    @Test
    public void testIfCustomObjectsAreRetained() {
        Assume.assumeTrue(System.getProperty("os.name").contains("iOS"));

        CustomUIView c1 = new CustomUIView();
        CustomNSCacheDelegateAdapter c2 = new CustomNSCacheDelegateAdapter();
        CustomCFString c3 = new CustomCFString("");

        NSCache cache = new NSCache();
        cache.put("1", c1);
        cache.put("2", c2);
        cache.put("3", c3.as(NSObject.class));

        assertEquals(true, ObjCObject.ObjectOwnershipHelper.isObjectRetained(c1));
        assertEquals(true, ObjCObject.ObjectOwnershipHelper.isObjectRetained(c2));
        assertEquals(false, ObjCObject.ObjectOwnershipHelper.isObjectRetained(c3.as(NSObject.class)));
    }

    /**
     * Only custom objects should get the hooks to retain and release.
     */
    @Test
    public void testIfOnlyCustomObjectsAreRetained() {
        Assume.assumeTrue(System.getProperty("os.name").contains("iOS"));

        CustomUIView custom = new CustomUIView();
        NSObject default1 = new NSObject();
        UIView default2 = new UIView();

        NSCache cache = new NSCache();
        cache.put("1", custom);
        cache.put("2", default1);
        cache.put("3", default2);

        assertEquals(true, ObjCObject.ObjectOwnershipHelper.isObjectRetained(custom));
        assertEquals(false, ObjCObject.ObjectOwnershipHelper.isObjectRetained(default1));
        assertEquals(false, ObjCObject.ObjectOwnershipHelper.isObjectRetained(default2));
    }

    private void addNewCustomObjectToCache(NSCache cache, String id, String stringValue, long longValue) {
        cache.put(id, new CustomNSObject(stringValue, longValue));
    }
    
    /**
     * Every retained object should not be GCed and lose the values of its variables.
     */
    @Test
    public void testIfCustomObjectsVariablesAreRetained() {
        final String stringValue = "ABC";
        final long longValue = 123;

        NSCache cache = new NSCache();
        // We don't want to have any reference to the CustomNSObject. 
        // If it were not stored with the ownership helper, it would get GCed immediately.
        addNewCustomObjectToCache(cache, "1", stringValue, longValue);
        forceGC();

        CustomNSObject custom = (CustomNSObject) cache.get("1");
        assertEquals(stringValue, custom.stringValue);
        assertEquals(longValue, custom.longValue);
    }

    /**
     * Custom objects that have been released shouldn't be referenced any longer
     * on the Java side. But if they are retained again, also reference them
     * again.
     */
    @Test
    public void testIfCustomObjectsAreCorrectlyReferenced() {
        Assume.assumeTrue(System.getProperty("os.name").contains("iOS"));

        CustomUIView custom = new CustomUIView();

        NSCache cache = new NSCache();
        cache.put("1", custom);
        assertEquals(true, ObjCObject.ObjectOwnershipHelper.isObjectRetained(custom));

        cache.remove("1");
        assertEquals(false, ObjCObject.ObjectOwnershipHelper.isObjectRetained(custom));

        cache.put("2", custom);
        assertEquals(true, ObjCObject.ObjectOwnershipHelper.isObjectRetained(custom));

        cache.remove("2");
        assertEquals(false, ObjCObject.ObjectOwnershipHelper.isObjectRetained(custom));
    }

    private static void forceGC() {
        for (int i = 0; i < 10; i++) {
            System.gc();
        }
    }
}