/*

 * Copied from TtsEngine.h from Android sources.

 * No modifications.

 */

/*

 * Copyright (C) 2009 Google Inc.

 *

 * 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.

 */

#include <media/AudioSystem.h>



// This header defines the interface used by the Android platform

// to access Text-To-Speech functionality in shared libraries that implement

// speech synthesis and the management of resources associated with the

// synthesis.

// An example of the implementation of this interface can be found in

// FIXME: add path+name to implementation of default TTS engine

// Libraries implementing this interface are used in:

//  frameworks/base/tts/jni/android_tts_SpeechSynthesis.cpp



namespace android {



enum tts_synth_status {

    TTS_SYNTH_DONE              = 0,

    TTS_SYNTH_PENDING           = 1

};



enum tts_callback_status {

    TTS_CALLBACK_HALT           = 0,

    TTS_CALLBACK_CONTINUE       = 1

};



// The callback is used by the implementation of this interface to notify its

// client, the Android TTS service, that the last requested synthesis has been

// completed. // TODO reword

// The callback for synthesis completed takes:

// @param [inout] void *&       - The userdata pointer set in the original

//                                 synth call

// @param [in]    uint32_t      - Track sampling rate in Hz

// @param [in]    uint32_t      - The audio format

// @param [in]    int           - The number of channels

// @param [inout] int8_t *&     - A buffer of audio data only valid during the

//                                execution of the callback

// @param [inout] size_t  &     - The size of the buffer

// @param [in] tts_synth_status - indicate whether the synthesis is done, or

//                                 if more data is to be synthesized.

// @return TTS_CALLBACK_HALT to indicate the synthesis must stop,

//         TTS_CALLBACK_CONTINUE to indicate the synthesis must continue if

//            there is more data to produce.

typedef tts_callback_status (synthDoneCB_t)(void *&, uint32_t,

        uint32_t, int, int8_t *&, size_t&, tts_synth_status);



class TtsEngine;

extern "C" TtsEngine* getTtsEngine();



enum tts_result {

    TTS_SUCCESS                 = 0,

    TTS_FAILURE                 = -1,

    TTS_FEATURE_UNSUPPORTED     = -2,

    TTS_VALUE_INVALID           = -3,

    TTS_PROPERTY_UNSUPPORTED    = -4,

    TTS_PROPERTY_SIZE_TOO_SMALL = -5,

    TTS_MISSING_RESOURCES       = -6

};



enum tts_support_result {

    TTS_LANG_COUNTRY_VAR_AVAILABLE = 2,

    TTS_LANG_COUNTRY_AVAILABLE = 1,

    TTS_LANG_AVAILABLE = 0,

    TTS_LANG_MISSING_DATA = -1,

    TTS_LANG_NOT_SUPPORTED = -2

};



class TtsEngine

{

public:

    virtual ~TtsEngine() {}



    // Initialize the TTS engine and returns whether initialization succeeded.

    // @param synthDoneCBPtr synthesis callback function pointer

    // @return TTS_SUCCESS, or TTS_FAILURE

    virtual tts_result init(synthDoneCB_t synthDoneCBPtr);



    // Shut down the TTS engine and releases all associated resources.

    // @return TTS_SUCCESS, or TTS_FAILURE

    virtual tts_result shutdown();



    // Interrupt synthesis and flushes any synthesized data that hasn't been

    // output yet. This will block until callbacks underway are completed.

    // @return TTS_SUCCESS, or TTS_FAILURE

    virtual tts_result stop();



    // Returns the level of support for the language, country and variant.

    // @return TTS_LANG_COUNTRY_VAR_AVAILABLE if the language, country and variant are supported,

    //            and the corresponding resources are correctly installed

    //         TTS_LANG_COUNTRY_AVAILABLE if the language and country are supported and the

    //             corresponding resources are correctly installed, but there is no match for

    //             the specified variant

    //         TTS_LANG_AVAILABLE if the language is supported and the

    //             corresponding resources are correctly installed, but there is no match for

    //             the specified country and variant

    //         TTS_LANG_MISSING_DATA if the required resources to provide any level of support

    //             for the language are not correctly installed

    //         TTS_LANG_NOT_SUPPORTED if the language is not supported by the TTS engine.

    virtual tts_support_result isLanguageAvailable(const char *lang, const char *country,

            const char *variant);



    // Load the resources associated with the specified language. The loaded

    // language will only be used once a call to setLanguage() with the same

    // language value is issued. Language and country values are coded according to the ISO three

    // letter codes for languages and countries, as can be retrieved from a java.util.Locale

    // instance. The variant value is encoded as the variant string retrieved from a

    // java.util.Locale instance built with that variant data.

    // @param lang pointer to the ISO three letter code for the language

    // @param country pointer to the ISO three letter code for the country

    // @param variant pointer to the variant code

    // @return TTS_SUCCESS, or TTS_FAILURE

    virtual tts_result loadLanguage(const char *lang, const char *country, const char *variant);

    

    // Load the resources associated with the specified language, country and Locale variant.

    // The loaded language will only be used once a call to setLanguageFromLocale() with the same

    // language value is issued. Language and country values are coded according to the ISO three

    // letter codes for languages and countries, as can be retrieved from a java.util.Locale

    // instance. The variant value is encoded as the variant string retrieved from a

    // java.util.Locale instance built with that variant data.

    // @param lang pointer to the ISO three letter code for the language

    // @param country pointer to the ISO three letter code for the country

    // @param variant pointer to the variant code

    // @return TTS_SUCCESS, or TTS_FAILURE

    virtual tts_result setLanguage(const char *lang, const char *country, const char *variant);



    // Retrieve the currently set language, country and variant, or empty strings if none of

    // parameters have been set. Language and country are represented by their 3-letter ISO code

    // @param[out]   pointer to the retrieved 3-letter code language value

    // @param[out]   pointer to the retrieved 3-letter code country value

    // @param[out]   pointer to the retrieved variant value

    // @return TTS_SUCCESS, or TTS_FAILURE

    virtual tts_result getLanguage(char *language, char *country, char *variant);



    // Notifies the engine what audio parameters should be used for the synthesis.

    // This is meant to be used as a hint, the engine implementation will set the output values

    // to those of the synthesis format, based on a given hint.

    // @param[inout] encoding in: the desired audio sample format

    //                         out: the format used by the TTS engine

    // @param[inout] rate in: the desired audio sample rate

    //                         out: the sample rate used by the TTS engine

    // @param[inout] channels in: the desired number of audio channels

    //                         out: the number of channels used by the TTS engine

    // @return TTS_SUCCESS, or TTS_FAILURE

    virtual tts_result setAudioFormat(AudioSystem::audio_format& encoding, uint32_t& rate,

            int& channels);



    // Set a property for the the TTS engine

    // "size" is the maximum size of "value" for properties "property"

    // @param property pointer to the property name

    // @param value    pointer to the property value

    // @param size     maximum size required to store this type of property

    // @return         TTS_PROPERTY_UNSUPPORTED, or TTS_SUCCESS, or TTS_FAILURE,

    //                  or TTS_VALUE_INVALID

    virtual tts_result setProperty(const char *property, const char *value,

            const size_t size);



    // Retrieve a property from the TTS engine

    // @param        property pointer to the property name

    // @param[out]   value    pointer to the retrieved language value

    // @param[inout] iosize   in: stores the size available to store the

    //                          property value.

    //                        out: stores the size required to hold the language

    //                          value if getLanguage() returned

    //                          TTS_PROPERTY_SIZE_TOO_SMALL, unchanged otherwise

    // @return TTS_PROPERTY_UNSUPPORTED, or TTS_SUCCESS,

    //         or TTS_PROPERTY_SIZE_TOO_SMALL

    virtual tts_result getProperty(const char *property, char *value,

            size_t *iosize);



    // Synthesize the text.

    // As the synthesis is performed, the engine invokes the callback to notify

    // the TTS framework that it has filled the given buffer, and indicates how

    // many bytes it wrote. The callback is called repeatedly until the engine

    // has generated all the audio data corresponding to the text.

    // Note about the format of the input: the text parameter may use the

    // following elements

    // and their respective attributes as defined in the SSML 1.0 specification:

    //    * lang

    //    * say-as:

    //          o interpret-as

    //    * phoneme

    //    * voice:

    //          o gender,

    //          o age,

    //          o variant,

    //          o name

    //    * emphasis

    //    * break:

    //          o strength,

    //          o time

    //    * prosody:

    //          o pitch,

    //          o contour,

    //          o range,

    //          o rate,

    //          o duration,

    //          o volume

    //    * mark

    // Differences between this text format and SSML are:

    //    * full SSML documents are not supported

    //    * namespaces are not supported

    // Text is coded in UTF-8.

    // @param text      the UTF-8 text to synthesize

    // @param userdata  pointer to be returned when the call is invoked

    // @param buffer    the location where the synthesized data must be written

    // @param bufferSize the number of bytes that can be written in buffer

    // @return          TTS_SUCCESS or TTS_FAILURE

    virtual tts_result synthesizeText(const char *text, int8_t *buffer,

            size_t bufferSize, void *userdata);



    // Synthesize IPA text.

    // As the synthesis is performed, the engine invokes the callback to notify

    // the TTS framework that it has filled the given buffer, and indicates how

    // many bytes it wrote. The callback is called repeatedly until the engine

    // has generated all the audio data corresponding to the IPA data.

    // @param ipa      the IPA data to synthesize

    // @param userdata  pointer to be returned when the call is invoked

    // @param buffer    the location where the synthesized data must be written

    // @param bufferSize the number of bytes that can be written in buffer

    // @return TTS_FEATURE_UNSUPPORTED if IPA is not supported,

    //         otherwise TTS_SUCCESS or TTS_FAILURE

    virtual tts_result synthesizeIpa(const char *ipa, int8_t *buffer,

            size_t bufferSize, void *userdata);

};



} // namespace android