/*

 * Copyright (c) 2011, 2013, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

//#define DND_DEBUG TRUE

#import "CDropTarget.h"

#import "AWTView.h"

#import "sun_lwawt_macosx_CDropTarget.h"

#import "java_awt_dnd_DnDConstants.h"

#import <JavaNativeFoundation/JavaNativeFoundation.h>

#import <JavaRuntimeSupport/JavaRuntimeSupport.h>

#include <objc/objc-runtime.h>

#import "CDragSource.h"

#import "CDataTransferer.h"

#import "DnDUtilities.h"

#import "ThreadUtilities.h"

static NSInteger        sDraggingSequenceNumber = -1;

static NSDragOperation    sDragOperation;

static NSDragOperation    sUpdateOperation;

static jint                sJavaDropOperation;

static NSPoint            sDraggingLocation;

static BOOL                sDraggingExited;

static BOOL                sDraggingError;

static NSUInteger        sPasteboardItemsCount = 0;

static NSArray*            sPasteboardTypes = nil;

static NSArray*            sPasteboardData = nil;

static jlongArray        sDraggingFormats = nil;

static CDropTarget*        sCurrentDropTarget;

extern JNFClassInfo jc_CDropTargetContextPeer;

@implementation CDropTarget

+ (CDropTarget *) currentDropTarget {

    return sCurrentDropTarget;

}

- (id)init:(jobject)jdropTarget component:(jobject)jcomponent peer:(jobject)jpeer control:(id)control

{

    self = [super init];

    DLog2(@"[CDropTarget init]: %@\n", self);

    fView = nil;

    fComponent = nil;

    fDropTarget = nil;

    fDropTargetContextPeer = nil;

    if (control != nil) {

        JNIEnv *env = [ThreadUtilities getJNIEnvUncached];

        fComponent = JNFNewGlobalRef(env, jcomponent);

        fDropTarget = JNFNewGlobalRef(env, jdropTarget);

        fView = [((AWTView *) control) retain];

        [fView setDropTarget:self];

    } else {

        // This would be an error.

        [self release];

        self = nil;

    }

    return self;

}

// When [CDropTarget init] is called the ControlModel's fView may not have been set up yet. ControlModel

// (soon after) calls [CDropTarget controlModelControlValid] on the native event thread, once per CDropTarget,

// to let it know it's been set up now.

- (void)controlModelControlValid

{

    // 9-30-02 Note: [Radar 3065621]

    // List all known pasteboard types here (see AppKit's NSPasteboard.h)

    // How to register for non-standard data types remains to be determined.

    NSArray* dataTypes = [[NSArray alloc] initWithObjects:

        NSStringPboardType,

        NSFilenamesPboardType,

        NSPostScriptPboardType,

        NSTIFFPboardType,

        NSRTFPboardType,

        NSTabularTextPboardType,

        NSFontPboardType,

        NSRulerPboardType,

        NSFileContentsPboardType,

        NSColorPboardType,

        NSRTFDPboardType,

        NSHTMLPboardType,

        NSURLPboardType,

        NSPDFPboardType,

        NSVCardPboardType,

        NSFilesPromisePboardType,

        [DnDUtilities javaPboardType],

        nil];

    // Enable dragging events over this object:

    [fView registerForDraggedTypes:dataTypes];

    [dataTypes release];

}

- (void)releaseDraggingData

{

    DLog2(@"[CDropTarget releaseDraggingData]: %@\n", self);

    // Release any old pasteboard types, data and properties:

    [sPasteboardTypes release];

    sPasteboardTypes = nil;

    [sPasteboardData release];

    sPasteboardData = nil;

    if (sDraggingFormats != NULL) {

        JNIEnv *env = [ThreadUtilities getJNIEnv];

        JNFDeleteGlobalRef(env, sDraggingFormats);

        sDraggingFormats = NULL;

    }

    sPasteboardItemsCount = 0;

    sDraggingSequenceNumber = -1;

}

- (void)removeFromView:(JNIEnv *)env

{

    DLog2(@"[CDropTarget removeFromView]: %@\n", self);

    // Remove this dragging destination from the view:

    [((AWTView *) fView) setDropTarget:nil];

    // Clean up JNI refs

    if (fComponent != NULL) {

        JNFDeleteGlobalRef(env, fComponent);

        fComponent = NULL;

    }

    if (fDropTarget != NULL) {

        JNFDeleteGlobalRef(env, fDropTarget);

        fDropTarget = NULL;

    }

    if (fDropTargetContextPeer != NULL) {

        JNFDeleteGlobalRef(env, fDropTargetContextPeer);

        fDropTargetContextPeer = NULL;

    }

    [self release];

}

- (void)dealloc

{

    DLog2(@"[CDropTarget dealloc]: %@\n", self);

    if(sCurrentDropTarget == self) {

        sCurrentDropTarget = nil;

    }

    [fView release];

    fView = nil;

    [super dealloc];

}

- (NSInteger) getDraggingSequenceNumber

{

    return sDraggingSequenceNumber;

}

// Debugging help:

- (void)dumpPasteboard:(NSPasteboard*)pasteboard

{

    NSArray* pasteboardTypes = [pasteboard types];

    NSUInteger pasteboardItemsCount = [pasteboardTypes count];

    NSUInteger i;

    // For each flavor on the pasteboard show the type, its data, and its property if there is one:

    for (i = 0; i < pasteboardItemsCount; i++) {

        NSString* pbType = [pasteboardTypes objectAtIndex:i];

        CFShow(pbType);

        NSData*    pbData = [pasteboard dataForType:pbType];

        CFShow(pbData);

        if ([pbType hasPrefix:@"CorePasteboardFlavorType"] == NO) {

            id pbDataProperty = [pasteboard propertyListForType:pbType];

            CFShow(pbDataProperty);

        }

    }

}

- (BOOL)copyDraggingTypes:(id<NSDraggingInfo>)sender

{

    DLog2(@"[CDropTarget copyDraggingTypes]: %@\n", self);

    JNIEnv*    env = [ThreadUtilities getJNIEnv];

    // Release any old pasteboard data:

    [self releaseDraggingData];

    NSPasteboard* pb = [sender draggingPasteboard];

    sPasteboardTypes = [[pb types] retain];

    sPasteboardItemsCount = [sPasteboardTypes count];

    if (sPasteboardItemsCount == 0)

        return FALSE;

    jlongArray formats = (*env)->NewLongArray(env, sPasteboardItemsCount);

    if (formats == nil)

        return FALSE;

    sDraggingFormats = (jlongArray) JNFNewGlobalRef(env, formats);

    (*env)->DeleteLocalRef(env, formats);

    if (sDraggingFormats == nil)

        return FALSE;

    jboolean isCopy;

    jlong* jformats = (*env)->GetLongArrayElements(env, sDraggingFormats, &isCopy);

    if (jformats == nil) {

        return FALSE;

    }

    // Copy all data formats and properties. In case of properties, if they are nil, we need to use

    // a special NilProperty since [NSArray addObject] would crash on adding a nil object.

    DLog2(@"[CDropTarget copyDraggingTypes]: typesCount = %lu\n", (unsigned long) sPasteboardItemsCount);

    NSUInteger i;

    for (i = 0; i < sPasteboardItemsCount; i++) {

        NSString* pbType = [sPasteboardTypes objectAtIndex:i];

        DLog3(@"[CDropTarget copyDraggingTypes]: type[%lu] = %@\n", (unsigned long) i, pbType);

        // 01-10-03 Note: until we need data properties for doing something useful don't copy them.

        // They're often copies of their flavor's data and copying them for all available pasteboard flavors

        // (which are often auto-translation of one another) can be a significant time/space hit.

        // If this is a remote object type (not a pre-defined format) register it with the pasteboard:

        jformats[i] = indexForFormat(pbType);

        if (jformats[i] == -1 && [pbType hasPrefix:@"JAVA_DATAFLAVOR:application/x-java-remote-object;"])

            jformats[i] = registerFormatWithPasteboard(pbType);

    }

    (*env)->ReleaseLongArrayElements(env, sDraggingFormats, jformats, JNI_COMMIT);

    return TRUE;

}

- (BOOL)copyDraggingData:(id<NSDraggingInfo>)sender

{

    DLog2(@"[CDropTarget copyDraggingData]: %@\n", self);

    sPasteboardData = [[NSMutableArray alloc] init];

    if (sPasteboardData == nil)

        return FALSE;

    // Copy all data items to a safe place since the pasteboard may go away before we'll need them:

    NSPasteboard* pb = [sender draggingPasteboard];

    NSUInteger i;

    for (i = 0; i < sPasteboardItemsCount; i++) {

        // Get a type and its data and save the data:

        NSString* pbType = [sPasteboardTypes objectAtIndex:i];

        // 01-10-03 Note: copying only NS-type data (until Java-specified types can make it through the AppKit)

        // would be a good idea since we can't do anything with those CoreFoundation unknown types anyway.

        // But I'm worried that it would break something in Fuller so I'm leaving this here as a reminder,

        // to be evaluated later.

        //id pbData = [pbType hasPrefix:@"NS"] ? [pb dataForType:pbType] : nil; // Copy only NS-type data!

        id pbData = [pb dataForType:pbType];

        // If the data is null we can't store it in the array - an exception would be thrown.

        // We use the special object NSNull instead which is kosher.

        if (pbData == nil)

            pbData = [NSNull null];

        [((NSMutableArray*) sPasteboardData) addObject:pbData];

    }

    return TRUE;

}

- (NSData*) getDraggingDataForURL:(NSData*)data

{

    NSData* result = nil;

    // Convert data into a property list if possible:

    NSPropertyListFormat propertyListFormat;

    NSString* errorString = nil;

    id propertyList = [NSPropertyListSerialization propertyListFromData:data mutabilityOption:NSPropertyListImmutable

        format:&propertyListFormat errorDescription:&errorString];

    // URL types have only a single URL string in an array:

    if (propertyList != nil && errorString == nil && [propertyList isKindOfClass:[NSArray class]]) {

        NSArray*  array = (NSArray*) propertyList;

        if ([array count] > 0) {

            NSString* url = (NSString*) [array objectAtIndex:0];

            if (url != nil && [url length] > 0)

                result = [url dataUsingEncoding:[url fastestEncoding]];

        }

    }

    return result;

}

- (jobject) copyDraggingDataForFormat:(jlong)format

{

    JNIEnv*      env = [ThreadUtilities getJNIEnvUncached]; // Join the main thread by requesting uncached environment

    NSData*      data = nil;

    // Convert the Java format (datatransferer int index) to a pasteboard format (NSString):

    NSString* pbType = formatForIndex(format);

    if ([sPasteboardTypes containsObject:pbType]) {

        NSUInteger dataIndex = [sPasteboardTypes indexOfObject:pbType];

        data = [sPasteboardData objectAtIndex:dataIndex];

        if ((id) data == [NSNull null])

            data = nil;

        // format == 8 (CF_URL in CDataTransferer): we need a URL-to-String conversion:

        else if ([pbType isEqualToString:@"Apple URL pasteboard type"])

            data = [self getDraggingDataForURL:data];

    }

    // Get NS data:

    char* dataBytes = (data != nil) ? (char*) [data bytes] : "Unsupported type";

    NSUInteger dataLength = (data != nil) ? [data length] : sizeof("Unsupported type");

    // Create a global byte array:

    jbyteArray lbyteArray = (*env)->NewByteArray(env, dataLength);

    if (lbyteArray == nil)

        return nil;

    jbyteArray gbyteArray = (jbyteArray) JNFNewGlobalRef(env, lbyteArray);

    (*env)->DeleteLocalRef(env, lbyteArray);

    if (gbyteArray == nil)

        return nil;

    // Get byte array elements:

    jboolean isCopy;

    jbyte* jbytes = (*env)->GetByteArrayElements(env, gbyteArray, &isCopy);

    if (jbytes == nil)

        return nil;

    // Copy data to byte array and release elements:

    memcpy(jbytes, dataBytes, dataLength);

    (*env)->ReleaseByteArrayElements(env, gbyteArray, jbytes, JNI_COMMIT);

    // In case of an error make sure to return nil:

    if ((*env)->ExceptionOccurred(env)) {

                (*env)->ExceptionDescribe(env);

        gbyteArray = nil;

        }

    return gbyteArray;

}

- (void)safeReleaseDraggingData:(NSNumber *)arg

{

    jlong draggingSequenceNumber = [arg longLongValue];

    // Make sure dragging data is released only if no new drag is under way. If a new drag

    // has been initiated it has released the old dragging data already. This has to be called

    // on the native event thread - otherwise we'd need to start synchronizing.

    if (draggingSequenceNumber == sDraggingSequenceNumber)

        [self releaseDraggingData];

}

- (void)javaDraggingEnded:(jlong)draggingSequenceNumber success:(BOOL)jsuccess action:(jint)jdropaction

{

    NSNumber *draggingSequenceNumberID = [NSNumber numberWithLongLong:draggingSequenceNumber];

        // Report back actual Swing success, not what AppKit thinks

        sDraggingError = !jsuccess;

        sDragOperation = [DnDUtilities mapJavaDragOperationToNS:jdropaction];

    // Release dragging data if any when Java's AWT event thread is all finished.

    // Make sure dragging data is released on the native event thread.

    [ThreadUtilities performOnMainThread:@selector(safeReleaseDraggingData:) on:self withObject:draggingSequenceNumberID waitUntilDone:NO];

}

- (jint)currentJavaActions {

    return [DnDUtilities mapNSDragOperationToJava:sUpdateOperation];

}

/********************************  BEGIN NSDraggingDestination Interface  ********************************/

// Private API to calculate the current Java actions

- (void) calculateCurrentSourceActions:(jint *)actions dropAction:(jint *)dropAction

{

    // Get the raw (unmodified by keys) source actions

    id jrsDrag = objc_lookUpClass("JRSDrag");

    if (jrsDrag != nil) {

        NSDragOperation rawDragActions = (NSDragOperation) [jrsDrag performSelector:@selector(currentAllowableActions)];

        if (rawDragActions != NSDragOperationNone) {

            // Both actions and dropAction default to the rawActions

            *actions = [DnDUtilities mapNSDragOperationMaskToJava:rawDragActions];

            *dropAction = *actions;

            // Get the current key modifiers.

            NSUInteger dragModifiers = (NSUInteger) [jrsDrag performSelector:@selector(currentModifiers)];

            // Either the drop action is narrowed as per Java rules (MOVE, COPY, LINK, NONE) or by the drag modifiers

            if (dragModifiers) {

                // Get the user selected operation based on the drag modifiers, then return the intersection

                NSDragOperation currentOp = [DnDUtilities nsDragOperationForModifiers:dragModifiers];

                NSDragOperation allowedOp = rawDragActions & currentOp;

                *dropAction = [DnDUtilities mapNSDragOperationToJava:allowedOp];

            }

        }

    }

    *dropAction = [DnDUtilities narrowJavaDropActions:*dropAction];

}

- (NSDragOperation)draggingEntered:(id<NSDraggingInfo>)sender

{

    DLog2(@"[CDropTarget draggingEntered]: %@\n", self);

    sCurrentDropTarget = self;

    JNIEnv* env = [ThreadUtilities getJNIEnv];

    NSInteger draggingSequenceNumber = [sender draggingSequenceNumber];

    // Set the initial drag operation return value:

    NSDragOperation dragOp = NSDragOperationNone;

        sJavaDropOperation = java_awt_dnd_DnDConstants_ACTION_NONE;

    // We could probably special-case some stuff if drag and drop objects match:

    //if ([sender dragSource] == fView)

    if (draggingSequenceNumber != sDraggingSequenceNumber) {

        sDraggingSequenceNumber = draggingSequenceNumber;

        sDraggingError = FALSE;

        // Delete any drop target context peer left over from a previous drag:

        if (fDropTargetContextPeer != NULL) {

            JNFDeleteGlobalRef(env, fDropTargetContextPeer);

            fDropTargetContextPeer = NULL;

        }

        // Look up the CDropTargetContextPeer class:

        JNF_STATIC_MEMBER_CACHE(getDropTargetContextPeerMethod, jc_CDropTargetContextPeer, "getDropTargetContextPeer", "()Lsun/lwawt/macosx/CDropTargetContextPeer;");

        if (sDraggingError == FALSE) {

            // Create a new drop target context peer:

            jobject dropTargetContextPeer = JNFCallStaticObjectMethod(env, getDropTargetContextPeerMethod);

            if (dropTargetContextPeer != nil) {

                fDropTargetContextPeer = JNFNewGlobalRef(env, dropTargetContextPeer);

                (*env)->DeleteLocalRef(env, dropTargetContextPeer);

            }

        }

        // Get dragging types (dragging data is only copied if dropped):

        if (sDraggingError == FALSE && [self copyDraggingTypes:sender] == FALSE)

            sDraggingError = TRUE;

    }

    if (sDraggingError == FALSE) {

        sDraggingExited = FALSE;

        sDraggingLocation = [sender draggingLocation];

        NSPoint javaLocation = [fView convertPoint:sDraggingLocation fromView:nil];

        javaLocation.y = fView.window.frame.size.height - javaLocation.y;

        DLog5(@"+ dragEnter: loc native %f, %f, java %f, %f\n", sDraggingLocation.x, sDraggingLocation.y, javaLocation.x, javaLocation.y);

                ////////// BEGIN Calculate the current drag actions //////////

                jint actions = java_awt_dnd_DnDConstants_ACTION_NONE;

        jint dropAction = actions;

                [self calculateCurrentSourceActions:&actions dropAction:&dropAction];

                sJavaDropOperation = dropAction;

                ////////// END Calculate the current drag actions //////////

        jlongArray formats = sDraggingFormats;

        JNF_MEMBER_CACHE(handleEnterMessageMethod, jc_CDropTargetContextPeer, "handleEnterMessage", "(Ljava/awt/Component;IIII[JJ)I");

        if (sDraggingError == FALSE) {

            // Double-casting self gets rid of 'different size' compiler warning:

            // AWT_THREADING Safe (CToolkitThreadBlockedHandler)

            actions = JNFCallIntMethod(env, fDropTargetContextPeer, handleEnterMessageMethod,

                                       fComponent, (jint) javaLocation.x, (jint) javaLocation.y,

                                       dropAction, actions, formats, ptr_to_jlong(self));

        }

        if (sDraggingError == FALSE) {

            // Initialize drag operation:

            sDragOperation = NSDragOperationNone;

            // Map Java actions back to NSDragOperation.

            // 1-6-03 Note: if the entry point of this CDropTarget isn't covered by a droppable component

            // (as can be the case with lightweight children) we must not return NSDragOperationNone

            // since that would prevent dropping into any of the contained drop targets.

            // Unfortunately there is no easy way to test this so we just test actions and override them

            // with GENERIC if necessary. Proper drag operations will be returned by draggingUpdated: which is

            // called right away, taking care of setting the right cursor and snap-back action.

            dragOp = ((actions != java_awt_dnd_DnDConstants_ACTION_NONE) ?

                [DnDUtilities mapJavaDragOperationToNS:dropAction] : NSDragOperationGeneric);

            // Remember the dragOp for no-op'd update messages:

            sUpdateOperation = dragOp;

        }

    }

    // 9-11-02 Note: the native event thread would not handle an exception gracefully:

    //if (sDraggingError == TRUE)

    //    [NSException raise:NSGenericException format:@"[CDropTarget draggingEntered] failed."];