'use client';

import { useEffect, useState } from 'react';
import { createClientComponentClient } from '@supabase/auth-helpers-nextjs';
import CameraCapture from "@/components/CameraCapture";
import BottleGrid from "@/components/BottleGrid";
import AuthForm from "@/components/AuthForm";
import BuddyList from "@/components/BuddyList";
import SessionList from "@/components/SessionList";

export default function Home() {
    const supabase = createClientComponentClient();
    const [bottles, setBottles] = useState<any[]>([]);
    const [isLoading, setIsLoading] = useState(true);
    const [user, setUser] = useState<any>(null);
    const [fetchError, setFetchError] = useState<string | null>(null);

    useEffect(() => {
        // Check session
        const checkUser = async () => {
            try {
                const { data: { session }, error } = await supabase.auth.getSession();
                console.log('Initial session check:', session ? 'User logged in' : 'No session');
                if (error) {
                    console.error('Session retrieval error:', error);
                }
                setUser(session?.user ?? null);
                if (session?.user) {
                    fetchCollection();
                }
            } catch (err) {
                console.error('Fatal error checking user:', err);
                setUser(null);
            } finally {
                setIsLoading(false);
            }
        };

        checkUser();

        // Listen for auth changes
        const { data: { subscription } } = supabase.auth.onAuthStateChange((event, session) => {
            console.log('Auth state change:', event, session?.user ? 'User logged in' : 'No user');
            setUser(session?.user ?? null);
            if (session?.user) {
                fetchCollection();
            } else {
                setBottles([]);
            }
        });

        return () => subscription.unsubscribe();
    }, []);

    const fetchCollection = async () => {
        setIsLoading(true);
        try {
            // Fetch bottles with their latest tasting date
            const { data, error } = await supabase
                .from('bottles')
                .select(`
          *,
          tastings (
            created_at
          )
        `)
                .order('created_at', { ascending: false });

            if (error) {
                console.error('Supabase fetch error:', error);
                throw error;
            }

            console.log(`Fetched ${data?.length || 0} bottles from Supabase`);

            // Process data to get the absolute latest tasting date for each bottle
            const processedBottles = (data || []).map(bottle => {
                const lastTasted = bottle.tastings && bottle.tastings.length > 0
                    ? bottle.tastings.reduce((latest: string, current: any) =>
                        new Date(current.created_at) > new Date(latest) ? current.created_at : latest,
                        bottle.tastings[0].created_at
                    )
                    : null;

                return {
                    ...bottle,
                    last_tasted: lastTasted
                };
            });

            setBottles(processedBottles);
        } catch (err: any) {
            console.error('Detailed fetch error:', err);
            setFetchError(err.message || JSON.stringify(err));
        } finally {
            setIsLoading(false);
        }
    };

    const handleLogout = async () => {
        await supabase.auth.signOut();
    };

    if (!user) {
        return (
            <main className="flex min-h-screen flex-col items-center justify-center p-6 bg-zinc-50 dark:bg-black">
                <div className="mb-12 text-center">
                    <h1 className="text-5xl font-black text-zinc-900 dark:text-white tracking-tighter mb-4">
                        WHISKY<span className="text-amber-600">VAULT</span>
                    </h1>
                    <p className="text-zinc-500 max-w-sm mx-auto">Scanne deine Flaschen, tracke deine Tastings und verwalte deinen Keller.</p>
                </div>
                <AuthForm />
            </main>
        );
    }

    return (
        <main className="flex min-h-screen flex-col items-center gap-6 md:gap-12 p-4 md:p-24 bg-zinc-50 dark:bg-black">
            <div className="z-10 max-w-5xl w-full flex flex-col items-center gap-8">
                <header className="w-full flex justify-between items-center">
                    <h1 className="text-4xl font-black text-zinc-900 dark:text-white tracking-tighter">
                        WHISKY<span className="text-amber-600">VAULT</span>
                    </h1>
                    <button
                        onClick={handleLogout}
                        className="text-sm font-medium text-zinc-500 hover:text-zinc-800 dark:hover:text-zinc-300 transition-colors"
                    >
                        Abmelden
                    </button>
                </header>

                <div className="grid grid-cols-1 md:grid-cols-2 gap-8 w-full max-w-5xl">
                    <div className="flex flex-col gap-8">
                        <CameraCapture onSaveComplete={fetchCollection} />
                        <SessionList />
                    </div>
                    <div>
                        <BuddyList />
                    </div>
                </div>

                <div className="w-full mt-12">
                    <h2 className="text-2xl font-bold mb-6 text-zinc-800 dark:text-zinc-100 flex items-center gap-3">
                        Deine Sammlung
                        <span className="text-sm font-normal text-zinc-500 bg-zinc-100 dark:bg-zinc-800 px-3 py-1 rounded-full">
                            {bottles.length}
                        </span>
                    </h2>

                    {isLoading ? (
                        <div className="flex justify-center py-12">
                            <div className="animate-spin rounded-full h-8 w-8 border-b-2 border-amber-600"></div>
                        </div>
                    ) : fetchError ? (
                        <div className="p-8 bg-zinc-100 dark:bg-zinc-900/50 border border-zinc-200 dark:border-zinc-800 rounded-3xl text-center">
                            <p className="text-zinc-800 dark:text-zinc-200 font-bold mb-2">Sammlung konnte nicht geladen werden</p>
                            <p className="text-zinc-500 text-sm italic mb-4">Möglicherweise müssen die Datenbank-Regeln aktualisiert werden.</p>
                            <button
                                onClick={fetchCollection}
                                className="px-6 py-2 bg-amber-600 hover:bg-amber-700 text-white rounded-xl text-xs font-bold uppercase tracking-widest transition-all"
                            >
                                Erneut versuchen
                            </button>
                        </div>
                    ) : (
                        <BottleGrid bottles={bottles} />
                    )}
                </div>
            </div>
        </main>
    );
}