// https://developer.mozilla.org/en-US/docs/Web/API/SpeechRecognition#events
interface SpeechRecognitionEventMap {
    audioend: Event;
    audiostart: Event;
    end: Event;
    error: SpeechRecognitionErrorEvent;
    nomatch: SpeechRecognitionEvent;
    result: SpeechRecognitionEvent;
    soundend: Event;
    soundstart: Event;
    speechend: Event;
    speechstart: Event;
    start: Event;
}

// https://wicg.github.io/speech-api/#speechreco-section
interface SpeechRecognition extends EventTarget {
    continuous: boolean;
    grammars: SpeechGrammarList;
    interimResults: boolean;
    lang: string;
    maxAlternatives: number;
    processLocally: boolean;
    onaudioend: ((this: SpeechRecognition, ev: Event) => any) | null;
    onaudiostart: ((this: SpeechRecognition, ev: Event) => any) | null;
    onend: ((this: SpeechRecognition, ev: Event) => any) | null;
    onerror: ((this: SpeechRecognition, ev: SpeechRecognitionErrorEvent) => any) | null;
    onnomatch: ((this: SpeechRecognition, ev: SpeechRecognitionEvent) => any) | null;
    onresult: ((this: SpeechRecognition, ev: SpeechRecognitionEvent) => any) | null;
    onsoundend: ((this: SpeechRecognition, ev: Event) => any) | null;
    onsoundstart: ((this: SpeechRecognition, ev: Event) => any) | null;
    onspeechend: ((this: SpeechRecognition, ev: Event) => any) | null;
    onspeechstart: ((this: SpeechRecognition, ev: Event) => any) | null;
    onstart: ((this: SpeechRecognition, ev: Event) => any) | null;
    abort(): void;
    start(audioTrack?: MediaStreamTrack): void;
    stop(): void;
    addEventListener<K extends keyof SpeechRecognitionEventMap>(
        type: K,
        listener: (this: SpeechRecognition, ev: SpeechRecognitionEventMap[K]) => any,
        options?: boolean | AddEventListenerOptions,
    ): void;
    addEventListener(
        type: string,
        listener: EventListenerOrEventListenerObject,
        options?: boolean | AddEventListenerOptions,
    ): void;
    removeEventListener<K extends keyof SpeechRecognitionEventMap>(
        type: K,
        listener: (this: SpeechRecognition, ev: SpeechRecognitionEventMap[K]) => any,
        options?: boolean | EventListenerOptions,
    ): void;
    removeEventListener(
        type: string,
        listener: EventListenerOrEventListenerObject,
        options?: boolean | EventListenerOptions,
    ): void;
}

// https://wicg.github.io/speech-api/#dictdef-speechrecognitionoptions
interface SpeechRecognitionOptions {
    langs: string[];
    processLocally: boolean;
}

type AvailabilityStatus =
    | "unavailable"
    | "downloadable"
    | "downloading"
    | "available";

// https://webaudio.github.io/web-speech-api/#speechrecognition
declare var SpeechRecognition: {
    prototype: SpeechRecognition;
    new(): SpeechRecognition;
    available(options: SpeechRecognitionOptions): Promise<AvailabilityStatus>;
    install(options: SpeechRecognitionOptions): Promise<boolean>;
};

// https://wicg.github.io/speech-api/#speechrecognitionevent
interface SpeechRecognitionEventInit extends EventInit {
    resultIndex?: number;
    results: SpeechRecognitionResultList;
}

// https://wicg.github.io/speech-api/#dictdef-speechrecognitioneventinit
interface SpeechRecognitionEvent extends Event {
    readonly resultIndex: number;
    readonly results: SpeechRecognitionResultList;
}

declare var SpeechRecognitionEvent: {
    prototype: SpeechRecognitionEvent;
    new(type: string, eventInitDict: SpeechRecognitionEventInit): SpeechRecognitionEvent;
};

// https://wicg.github.io/speech-api/#enumdef-speechrecognitionerrorcode
// type SpeechRecognitionErrorCode =
//     | "aborted"
//     | "audio-capture"
//     | "bad-grammar"
//     | "language-not-supported"
//     | "network"
//     | "no-speech"
//     | "not-allowed"
//     | "service-not-allowed";

// https://wicg.github.io/speech-api/#dictdef-speechrecognitionerroreventinit
interface SpeechRecognitionErrorEventInit extends EventInit {
    error: SpeechRecognitionErrorCode;
    message?: string;
}

// https://wicg.github.io/speech-api/#speechrecognitionerrorevent
interface SpeechRecognitionErrorEvent extends Event {
    readonly error: SpeechRecognitionErrorCode;
    readonly message: string;
}

declare var SpeechRecognitionErrorEvent: {
    prototype: SpeechRecognitionErrorEvent;
    new(type: string, eventInitDict: SpeechRecognitionErrorEventInit): SpeechRecognitionErrorEvent;
};

// https://wicg.github.io/speech-api/#speechgrammar
interface SpeechGrammar {
    src: string;
    weight: number;
}

declare var SpeechGrammar: {
    prototype: SpeechGrammar;
    new(): SpeechGrammar;
};

// https://wicg.github.io/speech-api/#speechgrammarlist
interface SpeechGrammarList {
    readonly length: number;
    addFromString(string: string, weight?: number): void;
    addFromURI(src: string, weight?: number): void;
    item(index: number): SpeechGrammar;
    [index: number]: SpeechGrammar;
}

declare var SpeechGrammarList: { prototype: SpeechGrammarList; new(): SpeechGrammarList };

// prefixed global variables in Chrome; should match the equivalents above
// https://developer.mozilla.org/en-US/docs/Web/API/Web_Speech_API/Using_the_Web_Speech_API#chrome_support
declare var webkitSpeechRecognition: { prototype: SpeechRecognition; new(): SpeechRecognition };
declare var webkitSpeechGrammarList: { prototype: SpeechGrammarList; new(): SpeechGrammarList };
declare var webkitSpeechRecognitionEvent: {
    prototype: SpeechRecognitionEvent;
    new(type: string, eventInitDict: SpeechRecognitionEventInit): SpeechRecognitionEvent;
};