import { useCallback, useEffect } from 'react';
import { createPortal } from 'react-dom';
import { useVoiceSession } from '../hooks/useVoiceSession';
import { isVoiceInputAvailable } from '../voice/capabilities';
import { VoiceWaveform } from './VoiceWaveform';

export function VoiceInputDialog({
  open,
  disabled = false,
  onClose,
  onSend,
  onError,
}: {
  open: boolean;
  disabled?: boolean;
  onClose: () => void;
  onSend: (text: string) => void;
  onError?: (message: string) => void;
}) {
  const { phase, text, analyser, liveRecognition, stopListening, finishFallbackRecording, resetSession } =
    useVoiceSession({
      active: open && !disabled,
      onError,
    });

  const handleClose = useCallback(() => {
    stopListening();
    resetSession();
    onClose();
  }, [onClose, resetSession, stopListening]);

  useEffect(() => {
    if (!open) return undefined;
    const previousOverflow = document.body.style.overflow;
    document.body.style.overflow = 'hidden';
    const onKeyDown = (event: KeyboardEvent) => {
      if (event.key === 'Escape') handleClose();
    };
    window.addEventListener('keydown', onKeyDown);
    return () => {
      document.body.style.overflow = previousOverflow;
      window.removeEventListener('keydown', onKeyDown);
    };
  }, [open, handleClose]);

  if (!open) return null;

  const listening = phase === 'listening';
  const transcribing = phase === 'transcribing';
  const busy = phase === 'requesting' || transcribing;
  const canSend = Boolean(text.trim()) && !busy && !disabled;

  const handleSend = () => {
    const value = text.trim();
    if (!value || disabled) return;
    stopListening();
    resetSession();
    onSend(value);
    onClose();
  };

  const statusText =
    phase === 'requesting'
      ? '正在准备麦克风…'
      : listening
        ? liveRecognition
          ? '正在聆听，文字会实时显示'
          : '正在录音，完成后点击「完成识别」'
        : transcribing
          ? '正在识别…'
          : '可编辑识别结果后发送';

  const supported = isVoiceInputAvailable();
  if (!supported) {
    return createPortal(
      <div className="voice-dialog-backdrop" role="presentation" onClick={handleClose}>
        <section className="voice-dialog" role="dialog" aria-modal="true" onClick={(e) => e.stopPropagation()}>
          <p className="voice-dialog-status">当前浏览器不支持语音输入，请改用文字发送。</p>
          <div className="voice-dialog-actions">
            <button type="button" className="ghost-btn" onClick={handleClose}>
              关闭
            </button>
          </div>
        </section>
      </div>,
      document.body,
    );
  }

  return createPortal(
    <div className="voice-dialog-backdrop" role="presentation" onClick={handleClose}>
      <section
        className="voice-dialog"
        role="dialog"
        aria-modal="true"
        aria-labelledby="voice-dialog-title"
        onClick={(event) => event.stopPropagation()}
      >
        <div className="voice-dialog-header">
          <div>
            <p className="voice-dialog-eyebrow">语音输入</p>
            <h3 id="voice-dialog-title">说出你想发送的内容</h3>
          </div>
          <button type="button" className="voice-dialog-close" onClick={handleClose} aria-label="关闭">
            关闭
          </button>
        </div>

        <VoiceWaveform analyser={analyser} active={listening || phase === 'requesting'} />

        <p className="voice-dialog-status" role="status">
          {transcribing ? <span className="voice-btn-spinner" aria-hidden="true" /> : null}
          {statusText}
        </p>

        <textarea
          className="voice-dialog-input input"
          rows={4}
          placeholder={listening ? '识别文字会出现在这里…' : '输入或编辑要发送的内容…'}
          value={text}
          disabled={busy}
          onChange={(event) => updateText(event.target.value)}
        />

        <div className="voice-dialog-actions">
          <button type="button" className="ghost-btn" onClick={handleClose}>
            取消
          </button>
          {!liveRecognition && listening ? (
            <button
              type="button"
              className="ghost-btn"
              disabled={transcribing}
              onClick={() => void finishFallbackRecording()}
            >
              完成识别
            </button>
          ) : null}
          <button type="button" className="send-btn" disabled={!canSend} onClick={handleSend}>
            发送
          </button>
        </div>
      </section>
    </div>,
    document.body,
  );
}