'use client';

import { useState, useEffect } from 'react';
import { Brain, Clock, Heart, BookOpen, Sparkles, ChevronRight, RefreshCw } from 'lucide-react';

interface Episode {
  id: string;
  content: string;
  insight: string;
  emotion: string;
  timestamp: string;
  type: 'conversation' | 'reflection' | 'prayer' | 'scripture';
}

const emotionColors: Record<string, { bg: string; text: string; border: string }> = {
  joy: { bg: 'bg-amber-500/10', text: 'text-amber-400', border: 'border-amber-500/30' },
  peace: { bg: 'bg-emerald-500/10', text: 'text-emerald-400', border: 'border-emerald-500/30' },
  hope: { bg: 'bg-blue-500/10', text: 'text-blue-400', border: 'border-blue-500/30' },
  gratitude: { bg: 'bg-purple-500/10', text: 'text-purple-400', border: 'border-purple-500/30' },
  seeking: { bg: 'bg-violet-500/10', text: 'text-violet-400', border: 'border-violet-500/30' },
  sorrow: { bg: 'bg-rose-500/10', text: 'text-rose-400', border: 'border-rose-500/30' },
  neutral: { bg: 'bg-neutral-500/10', text: 'text-neutral-400', border: 'border-neutral-500/30' },
};

const typeIcons = {
  conversation: Brain,
  reflection: Sparkles,
  prayer: Heart,
  scripture: BookOpen,
};

// Mock data - in production this would come from the API
const mockEpisodes: Episode[] = [
  {
    id: '1',
    content: 'Asked about dealing with anxiety and finding peace',
    insight: 'Seeking comfort through Scripture - Philippians 4:6-7 resonated',
    emotion: 'seeking',
    timestamp: new Date(Date.now() - 1000 * 60 * 30).toISOString(),
    type: 'conversation',
  },
  {
    id: '2',
    content: 'Morning prayer for guidance in career decision',
    insight: 'Trust in divine timing while taking practical steps',
    emotion: 'hope',
    timestamp: new Date(Date.now() - 1000 * 60 * 60 * 2).toISOString(),
    type: 'prayer',
  },
  {
    id: '3',
    content: 'Studied Psalm 23 with ORA',
    insight: 'The shepherd metaphor connects protection with provision',
    emotion: 'peace',
    timestamp: new Date(Date.now() - 1000 * 60 * 60 * 24).toISOString(),
    type: 'scripture',
  },
  {
    id: '4',
    content: 'Journaled about gratitude for community',
    insight: 'Fellowship strengthens faith during difficult seasons',
    emotion: 'gratitude',
    timestamp: new Date(Date.now() - 1000 * 60 * 60 * 48).toISOString(),
    type: 'reflection',
  },
];

function formatTimeAgo(timestamp: string): string {
  const now = new Date();
  const date = new Date(timestamp);
  const diff = now.getTime() - date.getTime();

  const minutes = Math.floor(diff / (1000 * 60));
  const hours = Math.floor(diff / (1000 * 60 * 60));
  const days = Math.floor(diff / (1000 * 60 * 60 * 24));

  if (minutes < 60) return `${minutes}m ago`;
  if (hours < 24) return `${hours}h ago`;
  if (days === 1) return 'Yesterday';
  if (days < 7) return `${days}d ago`;
  return date.toLocaleDateString();
}

interface MemoryTimelineProps {
  compact?: boolean;
  maxItems?: number;
}

export default function MemoryTimeline({ compact = false, maxItems = 5 }: MemoryTimelineProps) {
  const [episodes, setEpisodes] = useState<Episode[]>([]);
  const [loading, setLoading] = useState(true);
  const [error, setError] = useState<string | null>(null);

  const fetchEpisodes = async () => {
    setLoading(true);
    setError(null);
    try {
      // Try to fetch from backend
      const response = await fetch('http://localhost:6000/api/memory/episodes', {
        method: 'GET',
        headers: { 'Content-Type': 'application/json' },
      });

      if (response.ok) {
        const data = await response.json();
        setEpisodes(data.episodes || []);
      } else {
        // Use mock data if API not available
        setEpisodes(mockEpisodes);
      }
    } catch {
      // Use mock data on error
      setEpisodes(mockEpisodes);
    } finally {
      setLoading(false);
    }
  };

  useEffect(() => {
    fetchEpisodes();
  }, []);

  const displayEpisodes = episodes.slice(0, maxItems);

  if (compact) {
    return (
      <div className="space-y-2">
        <div className="flex items-center justify-between mb-3">
          <div className="flex items-center gap-2">
            <Brain className="w-4 h-4 text-purple-400" />
            <span className="text-sm font-medium text-white">Recent Memories</span>
          </div>
          <button
            onClick={fetchEpisodes}
            className="p-1 rounded hover:bg-white/5 text-neutral-500 hover:text-white transition-colors"
          >
            <RefreshCw className={`w-3.5 h-3.5 ${loading ? 'animate-spin' : ''}`} />
          </button>
        </div>

        {loading ? (
          <div className="space-y-2">
            {[1, 2, 3].map((i) => (
              <div key={i} className="h-12 rounded-lg bg-white/5 animate-pulse" />
            ))}
          </div>
        ) : (
          <div className="space-y-2">
            {displayEpisodes.map((episode) => {
              const colors = emotionColors[episode.emotion] || emotionColors.neutral;
              const Icon = typeIcons[episode.type];
              return (
                <div
                  key={episode.id}
                  className={`p-3 rounded-xl ${colors.bg} border ${colors.border} hover:scale-[1.02] transition-transform cursor-pointer`}
                >
                  <div className="flex items-start gap-2">
                    <Icon className={`w-4 h-4 ${colors.text} shrink-0 mt-0.5`} />
                    <div className="flex-1 min-w-0">
                      <p className="text-xs text-white/90 line-clamp-1">{episode.content}</p>
                      <div className="flex items-center gap-2 mt-1">
                        <span className={`text-[10px] ${colors.text}`}>{episode.emotion}</span>
                        <span className="text-[10px] text-neutral-600">
                          {formatTimeAgo(episode.timestamp)}
                        </span>
                      </div>
                    </div>
                  </div>
                </div>
              );
            })}
          </div>
        )}
      </div>
    );
  }

  return (
    <div className="h-full flex flex-col">
      {/* Header */}
      <div className="flex items-center justify-between p-4 border-b border-white/5">
        <div className="flex items-center gap-3">
          <div className="w-10 h-10 rounded-xl bg-purple-500/20 flex items-center justify-center border border-purple-500/30">
            <Brain className="w-5 h-5 text-purple-400" />
          </div>
          <div>
            <h2 className="text-lg font-semibold text-white">Episodic Memory</h2>
            <p className="text-xs text-neutral-500">Your spiritual journey timeline</p>
          </div>
        </div>
        <button
          onClick={fetchEpisodes}
          className="p-2 rounded-lg hover:bg-white/5 text-neutral-500 hover:text-white transition-colors"
        >
          <RefreshCw className={`w-4 h-4 ${loading ? 'animate-spin' : ''}`} />
        </button>
      </div>

      {/* Timeline */}
      <div className="flex-1 overflow-y-auto p-4">
        {loading ? (
          <div className="space-y-4">
            {[1, 2, 3, 4].map((i) => (
              <div key={i} className="h-24 rounded-xl bg-white/5 animate-pulse" />
            ))}
          </div>
        ) : error ? (
          <div className="text-center py-8">
            <p className="text-neutral-500 text-sm">{error}</p>
            <button
              onClick={fetchEpisodes}
              className="mt-2 text-purple-400 text-sm hover:underline"
            >
              Try again
            </button>
          </div>
        ) : episodes.length === 0 ? (
          <div className="text-center py-8">
            <Brain className="w-12 h-12 text-neutral-700 mx-auto mb-3" />
            <p className="text-neutral-500 text-sm">No memories yet</p>
            <p className="text-neutral-600 text-xs mt-1">
              Start a conversation to build your spiritual memory
            </p>
          </div>
        ) : (
          <div className="relative">
            {/* Timeline line */}
            <div className="absolute left-[19px] top-0 bottom-0 w-px bg-gradient-to-b from-purple-500/50 via-purple-500/20 to-transparent" />

            {/* Episodes */}
            <div className="space-y-4">
              {displayEpisodes.map((episode, index) => {
                const colors = emotionColors[episode.emotion] || emotionColors.neutral;
                const Icon = typeIcons[episode.type];
                return (
                  <div
                    key={episode.id}
                    className="relative pl-12 animate-fade-slide-in"
                    style={{ animationDelay: `${index * 100}ms` }}
                  >
                    {/* Timeline dot */}
                    <div
                      className={`absolute left-3 top-3 w-4 h-4 rounded-full ${colors.bg} border-2 ${colors.border} z-10`}
                    />

                    {/* Card */}
                    <div
                      className={`p-4 rounded-xl ${colors.bg} border ${colors.border} hover:scale-[1.01] transition-transform cursor-pointer group`}
                    >
                      <div className="flex items-start justify-between gap-3">
                        <div className="flex items-start gap-3">
                          <div className={`w-8 h-8 rounded-lg ${colors.bg} flex items-center justify-center shrink-0`}>
                            <Icon className={`w-4 h-4 ${colors.text}`} />
                          </div>
                          <div>
                            <p className="text-sm text-white/90">{episode.content}</p>
                            <p className="text-xs text-neutral-500 mt-1 italic">
                              "{episode.insight}"
                            </p>
                            <div className="flex items-center gap-3 mt-2">
                              <span className={`text-[10px] px-2 py-0.5 rounded-full ${colors.bg} ${colors.text} border ${colors.border}`}>
                                {episode.emotion}
                              </span>
                              <span className="text-[10px] text-neutral-600 flex items-center gap-1">
                                <Clock className="w-3 h-3" />
                                {formatTimeAgo(episode.timestamp)}
                              </span>
                            </div>
                          </div>
                        </div>
                        <ChevronRight className="w-4 h-4 text-neutral-600 group-hover:text-white transition-colors" />
                      </div>
                    </div>
                  </div>
                );
              })}
            </div>
          </div>
        )}
      </div>

      {/* Footer */}
      {episodes.length > maxItems && (
        <div className="p-4 border-t border-white/5">
          <button className="w-full py-2 text-sm text-purple-400 hover:text-purple-300 transition-colors">
            View all {episodes.length} memories
          </button>
        </div>
      )}
    </div>
  );
}