/*

 * Copyright (C) 2003, 2004, 2005, 2007, 2008, 2009, 2010 Apple Inc. All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 *

 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY

 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR

 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,

 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,

 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR

 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY

 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 */

#include "config.h"

#include "JNIUtility.h"

#if ENABLE(JAVA_BRIDGE)

#include <dlfcn.h>

namespace JSC {

namespace Bindings {

static jint KJSGetCreatedJavaVMs(JavaVM** vmBuf, jsize bufLen, jsize* nVMs)

{

    static void* javaVMFramework = 0;

    if (!javaVMFramework)

        javaVMFramework = dlopen("/System/Library/Frameworks/JavaVM.framework/JavaVM", RTLD_LAZY);

    if (!javaVMFramework)

        return JNI_ERR;

    typedef jint(*FunctionPointerType)(JavaVM**, jsize, jsize*);

    static FunctionPointerType functionPointer = 0;

    if (!functionPointer)

        functionPointer = reinterpret_cast<FunctionPointerType>(dlsym(javaVMFramework, "JNI_GetCreatedJavaVMs"));

    if (!functionPointer)

        return JNI_ERR;

    return functionPointer(vmBuf, bufLen, nVMs);

}

static JavaVM* jvm = 0;

// Provide the ability for an outside component to specify the JavaVM to use

// If the jvm value is set, the getJavaVM function below will just return.

// In getJNIEnv(), if AttachCurrentThread is called to a VM that is already

// attached, the result is a no-op.

void setJavaVM(JavaVM* javaVM)

{

    jvm = javaVM;

}

JavaVM* getJavaVM()

{

    if (jvm)

        return jvm;

    JavaVM* jvmArray[1];

    jsize bufLen = 1;

    jsize nJVMs = 0;

    jint jniError = 0;

    // Assumes JVM is already running ..., one per process

    jniError = KJSGetCreatedJavaVMs(jvmArray, bufLen, &nJVMs);

    if (jniError == JNI_OK && nJVMs > 0)

        jvm = jvmArray[0];

    else

        LOG_ERROR("JNI_GetCreatedJavaVMs failed, returned %ld", static_cast<long>(jniError));

    return jvm;

}

JNIEnv* getJNIEnv()

{

    union {

        JNIEnv* env;

        void* dummy;

    } u;

    jint jniError = 0;

    jniError = getJavaVM()->AttachCurrentThread(&u.dummy, 0);

    if (jniError == JNI_OK)

        return u.env;

    LOG_ERROR("AttachCurrentThread failed, returned %ld", static_cast<long>(jniError));

    return 0;

}

jmethodID getMethodID(jobject obj, const char* name, const char* sig)

{

    JNIEnv* env = getJNIEnv();

    jmethodID mid = 0;

    if (env) {

        jclass cls = env->GetObjectClass(obj);

        if (cls) {

            mid = env->GetMethodID(cls, name, sig);

            if (!mid) {

                env->ExceptionClear();

                mid = env->GetStaticMethodID(cls, name, sig);

                if (!mid)

                    env->ExceptionClear();

            }

        }

        env->DeleteLocalRef(cls);

    }

    return mid;

}

const char* getCharactersFromJString(jstring aJString)

{

    return getCharactersFromJStringInEnv(getJNIEnv(), aJString);

}

void releaseCharactersForJString(jstring aJString, const char* s)

{

    releaseCharactersForJStringInEnv(getJNIEnv(), aJString, s);

}

const char* getCharactersFromJStringInEnv(JNIEnv* env, jstring aJString)

{

    jboolean isCopy;

    const char* s = env->GetStringUTFChars(aJString, &isCopy);

    if (!s) {

        env->ExceptionDescribe();

        env->ExceptionClear();

        fprintf(stderr, "\n");

    }

    return s;

}

void releaseCharactersForJStringInEnv(JNIEnv* env, jstring aJString, const char* s)

{

    env->ReleaseStringUTFChars(aJString, s);

}

const jchar* getUCharactersFromJStringInEnv(JNIEnv* env, jstring aJString)

{

    jboolean isCopy;

    const jchar* s = env->GetStringChars(aJString, &isCopy);

    if (!s) {

        env->ExceptionDescribe();

        env->ExceptionClear();

        fprintf(stderr, "\n");

    }

    return s;

}

void releaseUCharactersForJStringInEnv(JNIEnv* env, jstring aJString, const jchar* s)

{

    env->ReleaseStringChars(aJString, s);

}

JNIType JNITypeFromClassName(const char* name)

{

    JNIType type;

    if (!strcmp("byte", name))

        type = byte_type;

    else if (!strcmp("short", name))

        type = short_type;

    else if (!strcmp("int", name))

        type = int_type;

    else if (!strcmp("long", name))

        type = long_type;

    else if (!strcmp("float", name))

        type = float_type;

    else if (!strcmp("double", name))

        type = double_type;

    else if (!strcmp("char", name))

        type = char_type;

    else if (!strcmp("boolean", name))

        type = boolean_type;

    else if (!strcmp("void", name))

        type = void_type;

    else if ('[' == name[0])

        type = array_type;

    else

        type = object_type;

    return type;

}

const char* signatureFromPrimitiveType(JNIType type)

{

    switch (type) {

    case void_type:

        return "V";

    case array_type:

        return "[";

    case object_type:

        return "L";

    case boolean_type:

        return "Z";

    case byte_type:

        return "B";

    case char_type:

        return "C";

    case short_type:

        return "S";

    case int_type:

        return "I";

    case long_type:

        return "J";

    case float_type:

        return "F";

    case double_type:

        return "D";

    case invalid_type:

    default:

        break;

    }

    return "";

}

JNIType JNITypeFromPrimitiveType(char type)

{

    switch (type) {

    case 'V':

        return void_type;

    case 'L':

        return object_type;

    case '[':

        return array_type;

    case 'Z':

        return boolean_type;

    case 'B':

        return byte_type;

    case 'C':

        return char_type;

    case 'S':

        return short_type;

    case 'I':

        return int_type;

    case 'J':

        return long_type;

    case 'F':

        return float_type;

    case 'D':

        return double_type;

    default:

        break;

    }

    return invalid_type;

}

jvalue getJNIField(jobject obj, JNIType type, const char* name, const char* signature)

{

    JavaVM* jvm = getJavaVM();

    JNIEnv* env = getJNIEnv();

    jvalue result;

    memset(&result, 0, sizeof(jvalue));

    if (obj && jvm && env) {

        jclass cls = env->GetObjectClass(obj);

        if (cls) {

            jfieldID field = env->GetFieldID(cls, name, signature);

            if (field) {

                switch (type) {

                case array_type:

                case object_type:

                    result.l = env->functions->GetObjectField(env, obj, field);

                    break;

                case boolean_type:

                    result.z = env->functions->GetBooleanField(env, obj, field);

                    break;

                case byte_type:

                    result.b = env->functions->GetByteField(env, obj, field);

                    break;

                case char_type:

                    result.c = env->functions->GetCharField(env, obj, field);

                    break;

                case short_type:

                    result.s = env->functions->GetShortField(env, obj, field);

                    break;

                case int_type:

                    result.i = env->functions->GetIntField(env, obj, field);

                    break;

                case long_type:

                    result.j = env->functions->GetLongField(env, obj, field);

                    break;

                case float_type:

                    result.f = env->functions->GetFloatField(env, obj, field);

                    break;

                case double_type:

                    result.d = env->functions->GetDoubleField(env, obj, field);

                    break;

                default:

                    LOG_ERROR("Invalid field type (%d)", static_cast<int>(type));

                }

            } else {

                LOG_ERROR("Could not find field: %s", name);

                env->ExceptionDescribe();

                env->ExceptionClear();

                fprintf(stderr, "\n");

            }

            env->DeleteLocalRef(cls);

        } else

            LOG_ERROR("Could not find class for object");

    }

    return result;

}

} // namespace Bindings

} // namespace JSC

#endif // ENABLE(JAVA_BRIDGE)