import { useEffect, useRef } from 'react';
import { FontAwesomeIcon } from '@fortawesome/react-fontawesome';
import { faSparkles, faMicrophone } from '@fortawesome/pro-duotone-svg-icons';
import { formatTimeFull } from '@/lib/format';
import { cx } from '@/utils/cx';

type TranscriptLine = {
    id: string;
    text: string;
    isFinal: boolean;
    timestamp: Date;
};

type Suggestion = {
    id: string;
    text: string;
    timestamp: Date;
};

type LiveTranscriptProps = {
    transcript: TranscriptLine[];
    suggestions: Suggestion[];
    connected: boolean;
};

export const LiveTranscript = ({ transcript, suggestions, connected }: LiveTranscriptProps) => {
    const scrollRef = useRef<HTMLDivElement>(null);

    useEffect(() => {
        if (scrollRef.current) {
            scrollRef.current.scrollTop = scrollRef.current.scrollHeight;
        }
    }, [transcript.length, suggestions.length]);

    // Merge transcript and suggestions by timestamp
    const items = [
        ...transcript.map(t => ({ ...t, kind: 'transcript' as const })),
        ...suggestions.map(s => ({ ...s, kind: 'suggestion' as const, isFinal: true })),
    ].sort((a, b) => a.timestamp.getTime() - b.timestamp.getTime());

    return (
        <div className="flex flex-1 flex-col overflow-hidden">
            {/* Header */}
            <div className="flex items-center gap-2 px-4 py-3 border-b border-secondary">
                <FontAwesomeIcon icon={faSparkles} className="size-3.5 text-fg-brand-primary" />
                <span className="text-xs font-bold uppercase tracking-wider text-brand-secondary">Live Assist</span>
                <div className={cx(
                    "ml-auto size-2 rounded-full",
                    connected ? "bg-success-solid" : "bg-disabled",
                )} />
            </div>

            {/* Transcript body */}
            <div ref={scrollRef} className="flex-1 overflow-y-auto px-4 py-3 space-y-2">
                {items.length === 0 && (
                    <div className="flex flex-col items-center justify-center py-8 text-center">
                        <FontAwesomeIcon icon={faMicrophone} className="size-6 text-fg-quaternary mb-2" />
                        <p className="text-xs text-quaternary">Listening to customer...</p>
                        <p className="text-xs text-quaternary">Transcript will appear here</p>
                    </div>
                )}

                {items.map(item => {
                    if (item.kind === 'suggestion') {
                        return (
                            <div key={item.id} className="rounded-lg bg-brand-primary p-3 border border-brand">
                                <div className="flex items-center gap-1.5 mb-1">
                                    <FontAwesomeIcon icon={faSparkles} className="size-3 text-fg-brand-primary" />
                                    <span className="text-xs font-semibold text-brand-secondary">AI Suggestion</span>
                                </div>
                                <p className="text-sm text-primary">{item.text}</p>
                            </div>
                        );
                    }

                    return (
                        <div key={item.id} className={cx(
                            "text-sm",
                            item.isFinal ? "text-primary" : "text-tertiary italic",
                        )}>
                            <span className="text-xs text-quaternary mr-2">
                                {formatTimeFull(item.timestamp.toISOString())}
                            </span>
                            {item.text}
                        </div>
                    );
                })}
            </div>
        </div>
    );
};