/*
 * Copyright 2012 Google Inc. All Rights Reserved.
 */

#ifndef WV_CONTENT_DECRYPTION_MODULE_H_
#define WV_CONTENT_DECRYPTION_MODULE_H_

#include <media/stagefright/foundation/ABase.h>
#include <utils/String8.h>
#include <utils/KeyedVector.h>
#include "sys/types.h"

#include <media/hardware/CryptoAPI.h>

namespace wvcdm {

class CdmDecryptor;

/**
 * This class allows the invoker of the ContentDecryptionModule to receive
 * license requests and error information. The invoker should provide a
 * concrete implementation for this class.
 */
class CdmClient
{
public:
    typedef enum {
        kErrorInvalidInitData = 0,
        kErrorInvalidKeyResponse = 1,
        kErrorInvalidSessionId = 2,
        kErrorCdmDecryptorInitializationFailed = 3,
        kErrorKeyAddFailed = 4
    } Error;

    CdmClient();
    virtual ~CdmClient();

    virtual void keyMessage(const android::String8& sessionId,
            const android::Vector<uint8_t>& message,
            const android::String8& defaultUrl) = 0;

    virtual void keyAdded(const android::String8& sessionId) = 0;
    virtual void keyError(const android::String8& sessionId, Error error) = 0;
};

/**
 * The ContentDecryptionModule provides a mechanism to create a license
 * request, handle the license response and handle decryption of content.
 */
class ContentDecryptionModule
{

public:
    explicit ContentDecryptionModule(CdmClient* client);
    virtual ~ContentDecryptionModule();

    /**
     * This generates a license request message and session ID for given
     * initialization data.
     *
     * @param[in] initData contains Content Protection system specific data
     *         (initialization or PSSH data).
     * @return false on error.
     * @note CdmClient::keyMessage and CdmClient::keyError may be called
     *         on successful license generation or error, respectively.
     */
    bool generateKeyRequest(const android::Vector<uint8_t>& initData);

    /**
     * This takes in a license response and sets up the crypto content
     * in preparation for decryption for a given session.
     *
     * @param[in] sessionId identifies the license request message created by
     *         generateKeyRequest though the CdmClient::KeyMessage method.
     * @param[in] keyResponse is the license response from the license server.
     * @note CdmClient::keyError may be called on error.
     */
    void addKey(const android::String8& sessionId,
            const android::Vector<uint8_t>& keyResponse);

    /**
     * TODO:rfrias,edwinwong: These interfaces are pending finalization
     * of OEMCrypto APIs
     */
    void decryptVideo(const uint8_t* keyId, const uint8_t* iv,
            size_t ivLength, const void* input,
            const android::CryptoPlugin::SubSample* subSamples,
            size_t numSubSamples, void* outputHandle, size_t* outputOffset,
            size_t* outputLength);

    /**
     * TODO:rfrias,edwinwong: These interfaces are pending finalization
     * of OEMCrypto APIs
     */
    void decryptAudio(const uint8_t* keyId, const uint8_t* iv,
            size_t ivLength, const void* input,
            const android::CryptoPlugin::SubSample* subSamples,
            size_t numSubSamples, void* output, size_t* outputLength);

    /**
     * This releases resources and crypto contexts associated with a
     * given session.
     *
     * @param[in] sessionId identifies a license and associated crypto
     *         contexts
     */
    virtual void closeSession(const android::String8& sessionId);

private:
    CdmClient* const mClient;
    android::KeyedVector<android::String8, CdmDecryptor*> mSessionIdToDecryptorMap;

    DISALLOW_EVIL_CONSTRUCTORS(ContentDecryptionModule);
};

}  // namespace wvcdm

#endif  // WV_CONTENT_DECRYPTION_MODULE_H_