Simple Speech-Enabled Call Router Using Dial Plan

; The confirmation macro will be used when the application receives input
; that has a middling confidence score. It will ask the user to confirm
; what he or she said. To do this, there are three prompts:
; confirm990.gsm, confirm991.gsm, and confirm992.gsm. The macro knows
; which to play based on the CONFIRMPROMPT variable, which is a string
; with the filname in it, made by combining the word "confirm" with 
; the recognized extension.
[macro-confirm]
exten => s,1,SpeechLoadGrammar(yesno|/etc/asterisk/grammars/yesno.gram)
exten => s,n,SpeechActivateGrammar(yesno)
exten => s,n,Set(CONFIRMPROMPT=$[confirm${ARG1}])
exten => s,n(PlayConfirm),SpeechBackground(didyouwant&${CONFIRMPROMPT}|5)
exten => s,n,GotoIf($[ ${SPEECH(results)} > 0]?Deactivate)
exten => s,n,Playback(NI)
exten => s,n,Goto(PlayConfirm)
exten => s,n(Deactivate),SpeechDeactivateGrammar(yesno)

; Answer the phone, create a speech port, load our directory grammar, call
; SpeechBackground to perform speech recognition while playing the sayname
; prompt. Then deactivate the grammar.
[speech-callrouter]
exten => s,1,Answer()
exten => s,n,SpeechCreate()
exten => s,n,SpeechLoadGrammar(directory|/etc/asterisk/grammars/directory.gram)
exten => s,n(Sayname),SpeechActivateGrammar(directory)
exten => s,n,SpeechBackground(sayname|10)
exten => s,n,SpeechDeactivateGrammar(directory)

; Check SPEECH(results) to ensure there was at least one result (i.e. we
; actually received spoken input). If not, we play the no input prompt and
; ask the caller to say something.
exten => s,n,GotoIf($[ ${SPEECH(results)} > 0]?InputOK)
exten => s,n,Playback(NI)
exten => s,n,Goto(Sayname)

; Now that we know there was input, we save the recognized extension to the
; variable DIALTHIS (important to do in case we overwrite SPEECH_TEXT with a 
; confirmation) and print some log messages to the console. Then we run
; a few checks on the confidence score. If it was really low (below 400), we
; will reject the utterance and have the user repeat what was said.
; If it was between 400 and 700, we launch the confirmation macro, passing in
; the recognized result as the only argument. If the user confirms by saying
; yes, or if the confidence score was above 700, we send the user to the
; specified extension.
exten => s,n(InputOK),Set(DIALTHIS=${SPEECH_TEXT(0)})
exten => s,n,Verbose(1,The recognized extension was ${SPEECH_TEXT(0)})
exten => s,n,Verbose(1,The score was ${SPEECH_SCORE(0)})
exten => s,n,GotoIf($[ ${SPEECH_SCORE(0)} < 400]?BadInput)
exten => s,n,GotoIf($[ ${SPEECH_SCORE(0)} > 700]?Dial)
exten => s,n,Macro(confirm,${SPEECH_TEXT(0)})
exten => s,n,GotoIf($[ "${SPEECH_TEXT(0)}" = "yes"]?Dial:Sayname)
exten => s,n(BadInput),Playback(didnotunderstand)
exten => s,n,Goto(Sayname)
exten => s,n(Dial),SpeechDestroy()
exten => s,n,Goto(${DIALTHIS},1)

exten => 990,1,Verbose(1,You called Tom Smith)
exten => 990,n,Playback(tomsmithgreeting)
exten => 990,n,Hangup()

exten => 991,1,Verbose(1,You called Joe Jones)
exten => 991,n,Playback(joejonesgreeting)
exten => 991,n,Hangup

exten => 992,1,Verbose(1,You called Bob Johnson)
exten => 991,n,Playback(bobjohnsongreeting)
exten => 992,n,Hangup