/*
 * Copyright (C) 2012 The Android Open Source Project
 *
 * 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.
 */

//#define LOG_NDEBUG 0
#define LOG_TAG "wv_crypto_plugin"
#include <utils/Log.h>

#include "WVCryptoPlugin.h"

#include <media/stagefright/foundation/ADebug.h>
#include <media/stagefright/foundation/hexdump.h>

#include <OEMCrypto_L1.h>

#include <string.h>

android::CryptoFactory *createCryptoFactory() {
    return new android::WVCryptoFactory;
}

namespace android {

// static
const uint8_t WVCryptoFactory::kUUIDWidevine[16] = {
    0xED,0xEF,0x8B,0xA9,0x79,0xD6,0x4A,0xCE,
    0xA3,0xC8,0x27,0xDC,0xD5,0x1D,0x21,0xED
};

WVCryptoPlugin::WVCryptoPlugin(const void *data, size_t size)
    : mInitCheck(NO_INIT) {

    // not using data at this time, require
    // size to be zero.
    if (size > 0) {
        mInitCheck = -EINVAL;
    } else {
        OEMCryptoResult res = OEMCrypto_Initialize();
        if (res != OEMCrypto_SUCCESS) {
            ALOGE("OEMCrypto_Initialize failed: %d", res);
            mInitCheck = -EINVAL;
        } else {
            mInitCheck = OK;
        }
    }
}

WVCryptoPlugin::~WVCryptoPlugin() {
    if (mInitCheck == OK) {
        OEMCryptoResult res = OEMCrypto_Terminate();
        if (res != OEMCrypto_SUCCESS) {
            ALOGW("OEMCrypto_Terminate failed: %d", res);
        }
    }
}

status_t WVCryptoPlugin::initCheck() const {
    return mInitCheck;
}

bool WVCryptoPlugin::requiresSecureDecoderComponent(const char *mime) const {
    return !strncasecmp(mime, "video/", 6);
}

status_t WVCryptoPlugin::decrypt(
        bool secure,
        const uint8_t key[16],
        const uint8_t iv[16],
        Mode mode,
        const void *srcPtr,
        const SubSample *subSamples, size_t numSubSamples,
        void *dstPtr,
        AString *errorDetailMsg) {
    Mutex::Autolock autoLock(mLock);

    //ALOGD("mode=%d, secure=%d, numSubSamples=%d", mode, secure, numSubSamples);
    CHECK(mode == kMode_Unencrypted || mode == kMode_AES_WV);

    size_t offset = 0;
    for (size_t i = 0; i < numSubSamples; ++i) {
        const SubSample &ss = subSamples[i];

        size_t srcSize;

        if (mode == kMode_Unencrypted) {
            srcSize = ss.mNumBytesOfClearData;
            CHECK_EQ(ss.mNumBytesOfEncryptedData, 0u);
        } else {
            CHECK_EQ(ss.mNumBytesOfClearData, 0u);
            srcSize = ss.mNumBytesOfEncryptedData;
        }

        //ALOGD("size[%d]=%d", i, srcSize);

        OEMCrypto_UINT32 dstLength = srcSize;

        OEMCryptoResult res;

        OEMCrypto_UINT8 _iv[16];
        const OEMCrypto_UINT8 *iv = NULL;

        if (mode != kMode_Unencrypted) {
            memset(_iv, 0, sizeof(_iv));
            iv = _iv;
        }

        if (secure) {
            //ALOGD("calling DecryptVideo, size=%d", srcSize);
            res = OEMCrypto_DecryptVideo(
                    iv,
                    (const OEMCrypto_UINT8 *)srcPtr + offset,
                    srcSize,
                    (OEMCrypto_UINT32)dstPtr,
                    offset,
                    &dstLength);
        } else {
            //ALOGD("calling DecryptAudio: size=%d", srcSize);
            res = OEMCrypto_DecryptAudio(
                    iv,
                    (const OEMCrypto_UINT8 *)srcPtr + offset,
                    srcSize,
                    (OEMCrypto_UINT8 *)dstPtr + offset,
                    &dstLength);
        }

        if (res != OEMCrypto_SUCCESS) {
            ALOGE("decrypt result: %d", res);
            return -EINVAL;
        }

        offset += dstLength;
    }

    return OK;
}

}  // namespace android