/***************************************************************************
 *   Copyright (C) 2005 to 2012 by Jonathan Duddington                     *
 *   email: jonsd@users.sourceforge.net                                    *
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 3 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 *   This program 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 for more details.                          *
 *                                                                         *
 *   You should have received a copy of the GNU General Public License     *
 *   along with this program; if not, see:                                 *
 *               <http://www.gnu.org/licenses/>.                           *
 ***************************************************************************/


/*************************************************************/
/* This is the header file for the library version of espeak */
/*                                                           */
/*************************************************************/
module speech.espeak.espeak;

import core.stdc.stdio;
import core.stdc.stddef;

extern(C):

enum ESPEAK_API_REVISION = 9;

/*
Revision 2
   Added parameter "options" to eSpeakInitialize()

Revision 3
   Added espeakWORDGAP to  espeak_PARAMETER

Revision 4
   Added flags parameter to espeak_CompileDictionary()

Revision 5
   Added espeakCHARS_16BIT

Revision 6
  Added macros: espeakRATE_MINIMUM, espeakRATE_MAXIMUM, espeakRATE_NORMAL

Revision 7  24.Dec.2011
  Changed espeak_EVENT structure to add id.string[] for phoneme mnemonics.
  Added espeakINITIALIZE_PHONEME_IPA option for espeak_Initialize() to report phonemes as IPA names.

Revision 8  26.Apr.2013
  Added function espeak_TextToPhonemes().

Revision 9  30.May.2013
  Changed function espeak_TextToPhonemes().

*/
         /********************/
         /*  Initialization  */
         /********************/

// values for 'value' in espeak_SetParameter(espeakRATE, value, 0), nominally in words-per-minute
enum espeakRATE_MINIMUM  = 80;
enum espeakRATE_MAXIMUM = 450;
enum espeakRATE_NORMAL = 175;

enum {
    espeakEVENT_LIST_TERMINATED = 0, // Retrieval mode: terminates the event list.
    espeakEVENT_WORD = 1,            // Start of word
    espeakEVENT_SENTENCE = 2,        // Start of sentence
    espeakEVENT_MARK = 3,            // Mark
    espeakEVENT_PLAY = 4,            // Audio element
    espeakEVENT_END = 5,             // End of sentence or clause
    espeakEVENT_MSG_TERMINATED = 6,  // End of message
    espeakEVENT_PHONEME = 7,         // Phoneme, if enabled in espeak_Initialize()
    espeakEVENT_SAMPLERATE = 8       // internal use, set sample rate
}

alias espeak_EVENT_TYPE = int;

struct espeak_EVENT {
	espeak_EVENT_TYPE type;
	uint unique_identifier; // message identifier (or 0 for key or character)
	int text_position;    // the number of characters from the start of the text
	int length;           // word length, in characters (for espeakEVENT_WORD)
	int audio_position;   // the time in mS within the generated speech output data
	int sample;           // sample id (internal use)
	void* user_data;      // pointer supplied by the calling program
	union {
		int number;        // used for WORD and SENTENCE events.
		const(char)* name;  // used for MARK and PLAY events.  UTF8 string
		char[8] string;    // used for phoneme names (UTF8). Terminated by a zero byte unless the name needs the full 8 bytes.
	}
}
/*
   When a message is supplied to espeak_synth, the request is buffered and espeak_synth returns. When the message is really processed, the callback function will be repetedly called.


   In RETRIEVAL mode, the callback function supplies to the calling program the audio data and an event list terminated by 0 (LIST_TERMINATED).

   In PLAYBACK mode, the callback function is called as soon as an event happens.

   For example suppose that the following message is supplied to espeak_Synth:
   "hello, hello."


   * Once processed in RETRIEVAL mode, it could lead to 3 calls of the callback function :

   ** Block 1:
   <audio data> +
   List of events: SENTENCE + WORD + LIST_TERMINATED

   ** Block 2:
   <audio data> +
   List of events: WORD + END + LIST_TERMINATED

   ** Block 3:
   no audio data
   List of events: MSG_TERMINATED + LIST_TERMINATED


   * Once processed in PLAYBACK mode, it could lead to 5 calls of the callback function:

   ** SENTENCE
   ** WORD (call when the sounds are actually played)
   ** WORD
   ** END (call when the end of sentence is actually played.)
   ** MSG_TERMINATED


   The MSG_TERMINATED event is the last event. It can inform the calling program to clear the user data related to the message.
   So if the synthesis must be stopped, the callback function is called for each pending message with the MSG_TERMINATED event.

   A MARK event indicates a <mark> element in the text.
   A PLAY event indicates an <audio> element in the text, for which the calling program should play the named sound file.
*/
enum {
	POS_CHARACTER = 1,
	POS_WORD,
	POS_SENTENCE
}

alias espeak_POSITION_TYPE = int;

enum {
	/* PLAYBACK mode: plays the audio data, supplies events to the calling program*/
	AUDIO_OUTPUT_PLAYBACK,

	/* RETRIEVAL mode: supplies audio data and events to the calling program */
	AUDIO_OUTPUT_RETRIEVAL,

	/* SYNCHRONOUS mode: as RETRIEVAL but doesn't return until synthesis is completed */
	AUDIO_OUTPUT_SYNCHRONOUS,

	/* Synchronous playback */
	AUDIO_OUTPUT_SYNCH_PLAYBACK
}

alias espeak_AUDIO_OUTPUT = int;

enum {
	EE_OK=0,
	EE_INTERNAL_ERROR=-1,
	EE_BUFFER_FULL=1,
	EE_NOT_FOUND=2
}

alias espeak_ERROR = int;

enum espeakINITIALIZE_PHONEME_EVENTS = 0x0001;
enum espeakINITIALIZE_PHONEME_IPA = 0x0002;
enum espeakINITIALIZE_DONT_EXIT = 0x8000;

int espeak_Initialize(espeak_AUDIO_OUTPUT output, int buflength, const(char)* path, int options);
/* Must be called before any synthesis functions are called.
   output: the audio data can either be played by eSpeak or passed back by the SynthCallback function.

   buflength:  The length in mS of sound buffers passed to the SynthCallback function.
            Value=0 gives a default of 200mS.
            This paramater is only used for AUDIO_OUTPUT_RETRIEVAL and AUDIO_OUTPUT_SYNCHRONOUS modes.

   path: The directory which contains the espeak-data directory, or NULL for the default location.

   options: bit 0:  1=allow espeakEVENT_PHONEME events.
            bit 1:  1= espeakEVENT_PHONEME events give IPA phoneme names, not eSpeak phoneme names
            bit 15: 1=don't exit if espeak_data is not found (used for --help)

   Returns: sample rate in Hz, or -1 (EE_INTERNAL_ERROR).
*/
alias t_espeak_callback = int function(short*, int, espeak_EVENT*);

void espeak_SetSynthCallback(t_espeak_callback SynthCallback);
/* Must be called before any synthesis functions are called.
   This specifies a function in the calling program which is called when a buffer of
   speech sound data has been produced.


   The callback function is of the form:

int SynthCallback(short *wav, int numsamples, espeak_EVENT *events);

   wav:  is the speech sound data which has been produced.
      NULL indicates that the synthesis has been completed.

   numsamples: is the number of entries in wav.  This number may vary, may be less than
      the value implied by the buflength parameter given in espeak_Initialize, and may
      sometimes be zero (which does NOT indicate end of synthesis).

   events: an array of espeak_EVENT items which indicate word and sentence events, and
      also the occurance if <mark> and <audio> elements within the text.  The list of
      events is terminated by an event of type = 0.


   Callback returns: 0=continue synthesis,  1=abort synthesis.
*/

alias t_espeak_uri_callback = int function(int, const(char)*, const(char)*);

void espeak_SetUriCallback(t_espeak_uri_callback UriCallback);
/* This function may be called before synthesis functions are used, in order to deal with
   <audio> tags.  It specifies a callback function which is called when an <audio> element is
   encountered and allows the calling program to indicate whether the sound file which
   is specified in the <audio> element is available and is to be played.

   The callback function is of the form:

int UriCallback(int type, const char *uri, const char *base);

   type:  type of callback event.  Currently only 1= <audio> element

   uri:   the "src" attribute from the <audio> element

   base:  the "xml:base" attribute (if any) from the <speak> element

   Return: 1=don't play the sound, but speak the text alternative.
           0=place a PLAY event in the event list at the point where the <audio> element
             occurs.  The calling program can then play the sound at that point.
*/


         /********************/
         /*    Synthesis     */
         /********************/


enum espeakCHARS_AUTO = 0;
enum espeakCHARS_UTF8 = 1;
enum espeakCHARS_8BIT = 2;
enum espeakCHARS_WCHAR = 3;
enum espeakCHARS_16BIT = 4;

enum espeakSSML = 0x10;
enum espeakPHONEMES = 0x100;
enum espeakENDPAUSE = 0x1000;
enum espeakKEEP_NAMEDATA = 0x2000;

espeak_ERROR espeak_Synth(const(void)* text,
	size_t size,
	uint position,
	espeak_POSITION_TYPE position_type,
	uint end_position,
	uint flags,
	uint* unique_identifier,
	void* user_data);
/* Synthesize speech for the specified text.  The speech sound data is passed to the calling
   program in buffers by means of the callback function specified by espeak_SetSynthCallback(). The command is asynchronous: it is internally buffered and returns as soon as possible. If espeak_Initialize was previously called with AUDIO_OUTPUT_PLAYBACK as argument, the sound data are played by eSpeak.

   text: The text to be spoken, terminated by a zero character. It may be either 8-bit characters,
      wide characters (wchar_t), or UTF8 encoding.  Which of these is determined by the "flags"
      parameter.

   size: Equal to (or greatrer than) the size of the text data, in bytes.  This is used in order
      to allocate internal storage space for the text.  This value is not used for
      AUDIO_OUTPUT_SYNCHRONOUS mode.

   position:  The position in the text where speaking starts. Zero indicates speak from the
      start of the text.

   position_type:  Determines whether "position" is a number of characters, words, or sentences.
      Values:

   end_position:  If set, this gives a character position at which speaking will stop.  A value
      of zero indicates no end position.

   flags:  These may be OR'd together:
      Type of character codes, one of:
         espeakCHARS_UTF8     UTF8 encoding
         espeakCHARS_8BIT     The 8 bit ISO-8859 character set for the particular language.
         espeakCHARS_AUTO     8 bit or UTF8  (this is the default)
         espeakCHARS_WCHAR    Wide characters (wchar_t)
         espeakCHARS_16BIT    16 bit characters.

      espeakSSML   Elements within < > are treated as SSML elements, or if not recognised are ignored.

      espeakPHONEMES  Text within [[ ]] is treated as phonemes codes (in espeak's Hirshenbaum encoding).

      espeakENDPAUSE  If set then a sentence pause is added at the end of the text.  If not set then
         this pause is suppressed.

   unique_identifier: This must be either NULL, or point to an integer variable to
       which eSpeak writes a message identifier number.
       eSpeak includes this number in espeak_EVENT messages which are the result of
       this call of espeak_Synth().

   user_data: a pointer (or NULL) which will be passed to the callback function in
       espeak_EVENT messages.

   Return: EE_OK: operation achieved
           EE_BUFFER_FULL: the command can not be buffered;
             you may try after a while to call the function again.
	   EE_INTERNAL_ERROR.
*/

espeak_ERROR espeak_Synth_Mark(const(void)* text,
	size_t size,
	const(char)* index_mark,
	uint end_position,
	uint flags,
	uint* unique_identifier,
	void* user_data);
/* Synthesize speech for the specified text.  Similar to espeak_Synth() but the start position is
   specified by the name of a <mark> element in the text.

   index_mark:  The "name" attribute of a <mark> element within the text which specified the
      point at which synthesis starts.  UTF8 string.

   For the other parameters, see espeak_Synth()

   Return: EE_OK: operation achieved
           EE_BUFFER_FULL: the command can not be buffered;
             you may try after a while to call the function again.
	   EE_INTERNAL_ERROR.
*/

espeak_ERROR espeak_Key(const(char)* key_name);
/* Speak the name of a keyboard key.
   If key_name is a single character, it speaks the name of the character.
   Otherwise, it speaks key_name as a text string.

   Return: EE_OK: operation achieved
           EE_BUFFER_FULL: the command can not be buffered;
             you may try after a while to call the function again.
	   EE_INTERNAL_ERROR.
*/

espeak_ERROR espeak_Char(wchar_t character);
/* Speak the name of the given character

   Return: EE_OK: operation achieved
           EE_BUFFER_FULL: the command can not be buffered;
             you may try after a while to call the function again.
	   EE_INTERNAL_ERROR.
*/




         /***********************/
         /*  Speech Parameters  */
         /***********************/

enum {
  espeakSILENCE=0, /* internal use */
  espeakRATE=1,
  espeakVOLUME=2,
  espeakPITCH=3,
  espeakRANGE=4,
  espeakPUNCTUATION=5,
  espeakCAPITALS=6,
  espeakWORDGAP=7,
  espeakOPTIONS=8,   // reserved for misc. options.  not yet used
  espeakINTONATION=9,

  espeakRESERVED1=10,
  espeakRESERVED2=11,
  espeakEMPHASIS,   /* internal use */
  espeakLINELENGTH, /* internal use */
  espeakVOICETYPE,  // internal, 1=mbrola
  N_SPEECH_PARAM    /* last enum */
}

alias espeak_PARAMETER = int;

enum {
  espeakPUNCT_NONE=0,
  espeakPUNCT_ALL=1,
  espeakPUNCT_SOME=2
}

alias  espeak_PUNCT_TYPE = int;

espeak_ERROR espeak_SetParameter(espeak_PARAMETER parameter, int value, int relative);
/* Sets the value of the specified parameter.
   relative=0   Sets the absolute value of the parameter.
   relative=1   Sets a relative value of the parameter.

   parameter:
      espeakRATE:    speaking speed in word per minute.  Values 80 to 450.

      espeakVOLUME:  volume in range 0-200 or more.
                     0=silence, 100=normal full volume, greater values may produce amplitude compression or distortion

      espeakPITCH:   base pitch, range 0-100.  50=normal

      espeakRANGE:   pitch range, range 0-100. 0-monotone, 50=normal

      espeakPUNCTUATION:  which punctuation characters to announce:
         value in espeak_PUNCT_TYPE (none, all, some),
         see espeak_GetParameter() to specify which characters are announced.

      espeakCAPITALS: announce capital letters by:
         0=none,
         1=sound icon,
         2=spelling,
         3 or higher, by raising pitch.  This values gives the amount in Hz by which the pitch
            of a word raised to indicate it has a capital letter.

      espeakWORDGAP:  pause between words, units of 10mS (at the default speed)

   Return: EE_OK: operation achieved
           EE_BUFFER_FULL: the command can not be buffered;
             you may try after a while to call the function again.
	   EE_INTERNAL_ERROR.
*/

int espeak_GetParameter(espeak_PARAMETER parameter, int current);
/* current=0  Returns the default value of the specified parameter.
   current=1  Returns the current value of the specified parameter, as set by SetParameter()
*/

espeak_ERROR espeak_SetPunctuationList(const(wchar_t)* punctlist);
/* Specified a list of punctuation characters whose names are to be spoken when the
   value of the Punctuation parameter is set to "some".

   punctlist:  A list of character codes, terminated by a zero character.

   Return: EE_OK: operation achieved
           EE_BUFFER_FULL: the command can not be buffered;
             you may try after a while to call the function again.
	   EE_INTERNAL_ERROR.
*/

void espeak_SetPhonemeTrace(int value, FILE *stream);
/* Controls the output of phoneme symbols for the text
   value=0  No phoneme output (default)
   value=1  Output the translated phoneme symbols for the text
   value=2  as (1), but also output a trace of how the translation was done (matching rules and list entries)
   value=3  as (1), but produces IPA rather than ascii phoneme names

   stream   output stream for the phoneme symbols (and trace).  If stream=NULL then it uses stdout.
*/

const(char)* espeak_TextToPhonemes(const(void)** textptr, int textmode, int phonememode);
/* Translates text into phonemes.  Call espeak_SetVoiceByName() first, to select a language.

   It returns a pointer to a character string which contains the phonemes for the text up to
   end of a sentence, or comma, semicolon, colon, or similar punctuation.

   textptr: The address of a pointer to the input text which is terminated by a zero character.
      On return, the pointer has been advanced past the text which has been translated, or else set
      to NULL to indicate that the end of the text has been reached.

   textmode: Type of character codes, one of:
         espeakCHARS_UTF8     UTF8 encoding
         espeakCHARS_8BIT     The 8 bit ISO-8859 character set for the particular language.
         espeakCHARS_AUTO     8 bit or UTF8  (this is the default)
         espeakCHARS_WCHAR    Wide characters (wchar_t)
         espeakCHARS_16BIT    16 bit characters.

   phonememode: bits0-3:
      0= just phonemes.
      1= include ties (U+361) for phoneme names of more than one letter.
      2= include zero-width-joiner for phoneme names of more than one letter.
      3= separate phonemes with underscore characters.

	 bits 4-7:
      0= eSpeak's ascii phoneme names.
      1= International Phonetic Alphabet (as UTF-8 characters).
*/

void espeak_CompileDictionary(const(char)* path, FILE *log, int flags);
/* Compile pronunciation dictionary for a language which corresponds to the currently
   selected voice.  The required voice should be selected before calling this function.

   path:  The directory which contains the language's '_rules' and '_list' files.
          'path' should end with a path separator character ('/').
   log:   Stream for error reports and statistics information. If log=NULL then stderr will be used.

   flags:  Bit 0: include source line information for debug purposes (This is displayed with the
          -X command line option).
*/
         /***********************/
         /*   Voice Selection   */
         /***********************/


// voice table
struct espeak_VOICE {
	immutable(char)* name;      // a given name for this voice. UTF8 string.
	immutable(char)* languages;       // list of pairs of (byte) priority + (string) language (and dialect qualifier)
	const(char)* identifier;      // the filename for this voice within espeak-data/voices
	char gender;  // 0=none 1=male, 2=female,
	char age;     // 0=not specified, or age in years
	char variant; // only used when passed as a parameter to espeak_SetVoiceByProperties
	char xx1;     // for internal use
	int score;       // for internal use
	void *spare;     // for internal use
}

/* Note: The espeak_VOICE structure is used for two purposes:
  1.  To return the details of the available voices.
  2.  As a parameter to  espeak_SetVoiceByProperties() in order to specify selection criteria.

   In (1), the "languages" field consists of a list of (UTF8) language names for which this voice
   may be used, each language name in the list is terminated by a zero byte and is also preceded by
   a single byte which gives a "priority" number.  The list of languages is terminated by an
   additional zero byte.

   A language name consists of a language code, optionally followed by one or more qualifier (dialect)
   names separated by hyphens (eg. "en-uk").  A voice might, for example, have languages "en-uk" and
   "en".  Even without "en" listed, voice would still be selected for the "en" language (because
   "en-uk" is related) but at a lower priority.

   The priority byte indicates how the voice is preferred for the language. A low number indicates a
   more preferred voice, a higher number indicates a less preferred voice.

   In (2), the "languages" field consists simply of a single (UTF8) language name, with no preceding
   priority byte.
*/

const(espeak_VOICE)** espeak_ListVoices(espeak_VOICE *voice_spec);
/* Reads the voice files from espeak-data/voices and creates an array of espeak_VOICE pointers.
   The list is terminated by a NULL pointer

   If voice_spec is NULL then all voices are listed.
   If voice spec is given, then only the voices which are compatible with the voice_spec
   are listed, and they are listed in preference order.
*/

espeak_ERROR espeak_SetVoiceByName(const(char)* name);
/* Searches for a voice with a matching "name" field.  Language is not considered.
   "name" is a UTF8 string.

   Return: EE_OK: operation achieved
           EE_BUFFER_FULL: the command can not be buffered;
             you may try after a while to call the function again.
	   EE_INTERNAL_ERROR.
*/

espeak_ERROR espeak_SetVoiceByProperties(espeak_VOICE *voice_spec);
/* An espeak_VOICE structure is used to pass criteria to select a voice.  Any of the following
   fields may be set:

   name     NULL, or a voice name

   languages  NULL, or a single language string (with optional dialect), eg. "en-uk", or "en"

   gender   0=not specified, 1=male, 2=female

   age      0=not specified, or an age in years

   variant  After a list of candidates is produced, scored and sorted, "variant" is used to index
            that list and choose a voice.
            variant=0 takes the top voice (i.e. best match). variant=1 takes the next voice, etc
*/

espeak_VOICE *espeak_GetCurrentVoice();
/* Returns the espeak_VOICE data for the currently selected voice.
   This is not affected by temporary voice changes caused by SSML elements such as <voice> and <s>
*/

espeak_ERROR espeak_Cancel();
/* Stop immediately synthesis and audio output of the current text. When this
   function returns, the audio output is fully stopped and the synthesizer is ready to
   synthesize a new message.

   Return: EE_OK: operation achieved
	   EE_INTERNAL_ERROR.
*/

int espeak_IsPlaying();
/* Returns 1 if audio is played, 0 otherwise.
*/

espeak_ERROR espeak_Synchronize();
/* This function returns when all data have been spoken.
   Return: EE_OK: operation achieved
	   EE_INTERNAL_ERROR.
*/

espeak_ERROR espeak_Terminate();
/* last function to be called.
   Return: EE_OK: operation achieved
	   EE_INTERNAL_ERROR.
*/

const(char)* espeak_Info(const(char)** path_data);
/* Returns the version number string.
   path_data  returns the path to espeak_data
*/