import React, { useState, useEffect } from 'react';
import { Card } from '../ui/card';
import { Button } from '../ui/button';
import { Play, Heart, TrendingUp, Sparkles, Calendar, ArrowRight, Disc, Loader2 } from 'lucide-react';
import { Track } from '../../types';
import { useAudio } from '../../context/AudioContext';
import { trackService } from '../../services/trackService';
import { useToast } from '../../context/ToastContext';
import { logger } from '@/utils/logger';

const GENRES = [
    { name: 'Synthwave', color: 'from-pink-500 to-purple-600' },
    { name: 'Techno', color: 'from-gray-700 to-black' },
    { name: 'Ambient', color: 'from-blue-400 to-teal-500' },
    { name: 'Lo-Fi', color: 'from-orange-300 to-red-400' },
    { name: 'Drum & Bass', color: 'from-yellow-400 to-orange-600' },
    { name: 'House', color: 'from-indigo-500 to-blue-600' },
];

export const DiscoverView: React.FC = () => {
    const { playTrack } = useAudio();
    const { addToast } = useToast();
    const [hoveredTrack, setHoveredTrack] = useState<string | null>(null);
    const [trending, setTrending] = useState<Track[]>([]);
    const [newReleases, setNewReleases] = useState<Track[]>([]);
    const [loading, setLoading] = useState(true);

    useEffect(() => {
        const fetchData = async () => {
            try {
                setLoading(true);
                const [trendingRes, newRes] = await Promise.all([
                    trackService.list({ sort_by: 'trending', limit: 5 }),
                    trackService.list({ sort_by: 'created_at', limit: 4 })
                ]);
                setTrending(trendingRes.tracks);
                setNewReleases(newRes.tracks);
            } catch (e) {
                logger.error('Failed to load discovery data', {
                    error: e instanceof Error ? e.message : String(e),
                    stack: e instanceof Error ? e.stack : undefined,
                });
                // Mock fallback
                setTrending([
                    { id: 't1', title: 'Midnight City', artist: 'M83', coverUrl: 'https://picsum.photos/id/10/300/300', duration: '4:03', durationSec: 243, play_count: 500000, like_count: 20000 } as unknown as Track,
                    { id: 't2', title: 'Nightcall', artist: 'Kavinsky', coverUrl: 'https://picsum.photos/id/20/300/300', duration: '4:18', durationSec: 258, play_count: 450000, like_count: 18000 } as unknown as Track,
                ]);
            } finally {
                setLoading(false);
            }
        };
        fetchData();
    }, []);

    const handlePlay = (track: Track) => {
        playTrack(track, trending);
    };

    if (loading) {
        return (
            <div className="flex h-[50vh] items-center justify-center">
                <Loader2 className="w-8 h-8 text-kodo-cyan animate-spin" />
            </div>
        );
    }

    return (
        <div className="animate-fadeIn space-y-12 pb-20">

            {/* Hero / For You */}
            <section>
                <div className="flex items-center gap-2 mb-6">
                    <Sparkles className="w-5 h-5 text-kodo-cyan" />
                    <h2 className="text-2xl font-display font-bold text-white">For You</h2>
                </div>

                <div className="grid grid-cols-1 md:grid-cols-2 lg:grid-cols-3 gap-6">
                    <Card variant="gaming" className="col-span-1 md:col-span-2 relative overflow-hidden group cursor-pointer h-64 flex items-end p-8 border-none" onClick={() => addToast("Playing Discovery Weekly")}>
                        <img src="https://picsum.photos/id/88/800/400" className="absolute inset-0 w-full h-full object-cover transition-transform duration-700 group-hover:scale-105 opacity-60 group-hover:opacity-40" />
                        <div className="absolute inset-0 bg-gradient-to-t from-black via-black/50 to-transparent"></div>
                        <div className="relative z-10 w-full">
                            <div className="text-kodo-cyan text-xs font-bold uppercase tracking-widest mb-2">Weekly Mix</div>
                            <h3 className="text-3xl font-bold text-white mb-2">Discover Weekly</h3>
                            <p className="text-gray-300 text-sm mb-4 line-clamp-1">Fresh tracks curated based on your listening history.</p>
                            <Button variant="primary" icon={<Play className="w-4 h-4 fill-current" />}>Play Now</Button>
                        </div>
                    </Card>

                    <Card variant="default" className="relative overflow-hidden group cursor-pointer h-64 p-6 flex flex-col justify-end">
                        <img src="https://picsum.photos/id/99/400/400" className="absolute inset-0 w-full h-full object-cover opacity-50 group-hover:opacity-30 transition-all" />
                        <div className="absolute inset-0 bg-gradient-to-t from-kodo-ink to-transparent"></div>
                        <div className="relative z-10">
                            <h3 className="text-xl font-bold text-white mb-1">New Arrivals</h3>
                            <p className="text-xs text-gray-400">Best of the week</p>
                        </div>
                        <div className="absolute top-4 right-4 bg-kodo-lime text-black text-[10px] font-bold px-2 py-1 rounded">UPDATED</div>
                    </Card>
                </div>
            </section>

            {/* Trending Now */}
            <section>
                <div className="flex items-center justify-between mb-6">
                    <div className="flex items-center gap-2">
                        <TrendingUp className="w-5 h-5 text-kodo-magenta" />
                        <h2 className="text-2xl font-display font-bold text-white">Trending Now</h2>
                    </div>
                    <Button variant="ghost" size="sm" className="text-gray-400 hover:text-white">View All <ArrowRight className="w-4 h-4 ml-1" /></Button>
                </div>

                <div className="space-y-2">
                    {trending.map((track, i) => (
                        <div
                            key={track.id}
                            className="flex items-center gap-4 p-3 rounded-xl hover:bg-white/5 group transition-colors cursor-pointer"
                            onMouseEnter={() => setHoveredTrack(track.id)}
                            onMouseLeave={() => setHoveredTrack(null)}
                            onClick={() => handlePlay(track)}
                        >
                            <div className="w-8 text-center font-bold text-gray-600">{i + 1}</div>
                            <div className="relative w-12 h-12 rounded-lg overflow-hidden flex-shrink-0">
                                <img src={track.coverUrl} className="w-full h-full object-cover" />
                                <div className={`absolute inset-0 bg-black/50 flex items-center justify-center transition-opacity ${hoveredTrack === track.id ? 'opacity-100' : 'opacity-0'}`}>
                                    <Play className="w-5 h-5 text-white fill-current" />
                                </div>
                            </div>
                            <div className="flex-1 min-w-0">
                                <div className="text-white font-bold truncate">{track.title}</div>
                                <div className="text-gray-400 text-xs truncate">{track.artist}</div>
                            </div>
                            <div className="text-gray-500 text-xs font-mono hidden md:block">{track.play_count.toLocaleString()} plays</div>
                            <div className="text-gray-500 text-xs font-mono">{track.duration}</div>
                            <button className="text-gray-500 hover:text-kodo-magenta p-2 opacity-0 group-hover:opacity-100 transition-opacity" onClick={(e) => { e.stopPropagation(); addToast("Liked"); }}><Heart className="w-4 h-4" /></button>
                        </div>
                    ))}
                </div>
            </section>

            {/* New Releases */}
            <section>
                <div className="flex items-center gap-2 mb-6">
                    <Calendar className="w-5 h-5 text-kodo-gold" />
                    <h2 className="text-2xl font-display font-bold text-white">New Releases</h2>
                </div>

                <div className="grid grid-cols-2 md:grid-cols-4 gap-6">
                    {newReleases.map(release => (
                        <div key={release.id} className="group cursor-pointer" onClick={() => handlePlay(release)}>
                            <div className="aspect-square rounded-xl overflow-hidden mb-3 relative shadow-lg">
                                <img src={release.coverUrl} className="w-full h-full object-cover group-hover:scale-105 transition-transform duration-500" />
                                <div className="absolute inset-0 bg-black/20 group-hover:bg-transparent transition-colors"></div>
                                <div className="absolute bottom-2 left-2 opacity-0 group-hover:opacity-100 transition-opacity">
                                    <Button variant="primary" size="icon" className="h-8 w-8"><Play className="w-4 h-4 fill-current" /></Button>
                                </div>
                            </div>
                            <h3 className="font-bold text-white truncate group-hover:text-kodo-gold transition-colors">{release.title}</h3>
                            <p className="text-xs text-gray-400">{release.artist}</p>
                        </div>
                    ))}
                </div>
            </section>

            {/* Popular Genres */}
            <section>
                <div className="flex items-center gap-2 mb-6">
                    <Disc className="w-5 h-5 text-gray-400" />
                    <h2 className="text-2xl font-display font-bold text-white">Browse by Genre</h2>
                </div>

                <div className="grid grid-cols-2 md:grid-cols-3 lg:grid-cols-6 gap-4">
                    {GENRES.map(genre => (
                        <div
                            key={genre.name}
                            className={`aspect-square rounded-xl bg-gradient-to-br ${genre.color} p-4 relative overflow-hidden cursor-pointer hover:scale-105 transition-transform duration-300`}
                            onClick={() => addToast(`Browsing ${genre.name}`)}
                        >
                            <span className="font-bold text-white text-lg relative z-10">{genre.name}</span>
                            <div className="absolute -bottom-2 -right-2 opacity-30 transform rotate-12">
                                <Disc className="w-16 h-16 text-white" />
                            </div>
                        </div>
                    ))}
                </div>
            </section>
        </div>
    );
};