import React, { useState, useEffect } from 'react';
import axios from 'axios';
import { Card, Typography, Spin, Drawer, Empty, Tag, Button } from 'antd';
import { CalendarOutlined, RightOutlined, HistoryOutlined, RobotOutlined } from '@ant-design/icons';
import NarrativeSection from './NarrativeSection';
import StatsGrid from './StatsGrid';
import TrackList from './TrackList';
import Navbar from './Navbar';

const { Title, Text } = Typography;

const Archives = () => {
  const [snapshots, setSnapshots] = useState([]);
  const [loading, setLoading] = useState(true);
  const [selectedSnapshot, setSelectedSnapshot] = useState(null);
  const [drawerVisible, setDrawerVisible] = useState(false);

  const fetchSnapshots = async () => {
    setLoading(true);
    try {
      const response = await axios.get('/api/snapshots');
      setSnapshots(response.data);
    } catch (error) {
      console.error('Failed to fetch snapshots:', error);
    } finally {
      setLoading(false);
    }
  };

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

  const handleSnapshotClick = (snapshot) => {
    setSelectedSnapshot(snapshot);
    setDrawerVisible(true);
  };

  const closeDrawer = () => {
    setDrawerVisible(false);
    setSelectedSnapshot(null);
  };

  // Helper to safely parse JSON if it comes as string (though axios usually handles it)
  const safeParse = (data) => {
    if (typeof data === 'string') {
      try {
        return JSON.parse(data);
      } catch (e) {
        return null;
      }
    }
    return data;
  };

  return (
    <>
      <Navbar showRefresh={false} />
      
      <main className="w-full max-w-7xl mx-auto px-4 sm:px-6 lg:px-8 py-8 space-y-8">
        <div className="flex items-center justify-between">
          <Title level={2} className="text-white !mb-0 flex items-center gap-3">
            <HistoryOutlined className="text-primary" />
            Archives
          </Title>
          <Text className="text-slate-400">
            {snapshots.length} Snapshot{snapshots.length !== 1 && 's'} Found
          </Text>
        </div>

        {loading ? (
          <div className="flex justify-center p-12">
            <Spin size="large" />
          </div>
        ) : snapshots.length === 0 ? (
          <div className="glass-panel p-12 text-center rounded-xl border border-dashed border-slate-700">
            <Empty description={<span className="text-slate-400">No archives found yet.</span>} />
          </div>
        ) : (
          <div className="grid grid-cols-1 md:grid-cols-2 lg:grid-cols-3 gap-6">
            {snapshots.map((snap) => {
              const narrative = safeParse(snap.narrative_report);
              const metrics = safeParse(snap.metrics_payload);
              const date = new Date(snap.created_at);
              
              return (
                <Card 
                  key={snap.id}
                  hoverable
                  className="bg-slate-800 border-slate-700 shadow-xl transition-all duration-300 hover:border-primary/50 group"
                  onClick={() => handleSnapshotClick(snap)}
                >
                  <div className="flex items-start justify-between mb-4">
                    <Tag icon={<CalendarOutlined />} color="blue">
                      {date.toLocaleDateString(undefined, { weekday: 'short', year: 'numeric', month: 'short', day: 'numeric' })}
                    </Tag>
                    <Text className="text-slate-500 text-xs font-mono">
                      {date.toLocaleTimeString(undefined, { hour: '2-digit', minute: '2-digit' })}
                    </Text>
                  </div>
                  
                  <div className="space-y-3">
                    <div>
                      <Text className="text-slate-400 text-xs uppercase tracking-wider block mb-1">Vibe</Text>
                      <Title level={4} className="!mt-0 !mb-1 text-white truncate">
                        {metrics?.vibe || 'Unknown Vibe'}
                      </Title>
                    </div>

                    <div>
                      <Text className="text-slate-400 text-xs uppercase tracking-wider block mb-1">Musical Era</Text>
                      <div className="flex items-center gap-2">
                         <span className="text-primary font-bold">
                           {metrics?.era?.musical_age || 'N/A'}
                         </span>
                      </div>
                    </div>

                    <div className="pt-4 border-t border-slate-700/50 flex justify-end">
                      <Button type="text" className="text-slate-400 group-hover:text-primary flex items-center gap-1 pl-0">
                        View Details <RightOutlined className="text-xs" />
                      </Button>
                    </div>
                  </div>
                </Card>
              );
            })}
          </div>
        )}

        <Drawer
          title={
            <div className="flex items-center gap-3">
              <CalendarOutlined className="text-primary" />
              <span className="text-white">
                Snapshot: {selectedSnapshot && new Date(selectedSnapshot.created_at).toLocaleDateString()}
              </span>
            </div>
          }
          placement="right"
          width={800} // Wide drawer
          onClose={closeDrawer}
          open={drawerVisible}
          className="bg-[#0f172a] text-white"
          styles={{
            header: { background: '#1e293b', borderBottom: '1px solid #334155' },
            body: { background: '#0f172a', padding: '24px' },
            mask: { backdropFilter: 'blur(4px)' }
          }}
        >
          {selectedSnapshot && (
            <div className="space-y-8">
              {/* Reuse components but pass the specific snapshot data */}
              <NarrativeSection 
                narrative={safeParse(selectedSnapshot.narrative_report)} 
                vibe={safeParse(selectedSnapshot.metrics_payload)?.vibe} 
              />
              
              <StatsGrid metrics={safeParse(selectedSnapshot.metrics_payload)} />
              
              {/* Playlist Compositions if available */}
              {selectedSnapshot.playlist_composition && (
                <div className="space-y-6">
                  <div className="flex items-center gap-2 mb-4">
                    <HistoryOutlined className="text-blue-400 text-xl" />
                    <Title level={3} className="!mb-0 text-white">Archived Playlists</Title>
                  </div>
                  
                  {/* We need to parse playlist composition if it's stored as JSON string */}
                  {(() => {
                    const playlists = safeParse(selectedSnapshot.playlist_composition);
                    if (!playlists) return <Text className="text-slate-500">No playlist data archived.</Text>;
                    
                    return (
                      <div className="grid grid-cols-1 gap-6">
                        {playlists.six_hour && (
                          <Card className="bg-slate-800 border-slate-700" title={<span className="text-blue-400">Short & Sweet (6h)</span>}>
                            <div className="mb-4">
                              <Text className="text-gray-400 text-xs uppercase tracking-wider block mb-1">Theme</Text>
                              <Text className="text-white font-medium block">{playlists.six_hour.theme}</Text>
                              <Paragraph className="text-gray-400 text-sm italic mt-1">{playlists.six_hour.reasoning}</Paragraph>
                            </div>
                            <TrackList tracks={playlists.six_hour.composition} />
                          </Card>
                        )}
                        
                        {playlists.daily && (
                          <Card className="bg-slate-800 border-slate-700" title={<span className="text-purple-400">Daily Devotion</span>}>
                             <div className="mb-4">
                              <Text className="text-gray-400 text-xs uppercase tracking-wider block mb-1">Strategy</Text>
                              <Text className="text-white font-medium block">Daily Mix</Text>
                            </div>
                            <TrackList tracks={playlists.daily.composition} />
                          </Card>
                        )}
                      </div>
                    );
                  })()}
                </div>
              )}
            </div>
          )}
        </Drawer>
      </main>
    </>
  );
};

export default Archives;