<?php

namespace App\Http\Controllers;

use App\Models\Book;
use App\Models\Category;
use App\Models\Loan;
use Carbon\Carbon;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\Auth;
use Illuminate\Support\Facades\DB;
use Illuminate\Support\Str;

class PeminjamanController extends Controller
{
    public function index(Request $request)
    {
        $user = Auth::user();

        // Check for overdue loans
        $hasOverdue = Loan::where('user_id', $user->id)
            ->whereIn('status', ['Dipinjam', 'Terlambat'])
            ->where('due_at', '<', now())
            ->exists();

        if (($hasOverdue || $user->is_banned) && $user->role === 'siswa') {
            return redirect()->route('dashboard')->with('error', 'AKSES DITOLAK: Akun Anda sedang dibekukan karena ada buku terlambat!');
        }

        $filters = $request->only(['search', 'kategori', 'tahun', 'penulis']);
        
        $query = Book::with('category')->whereJsonContains('tipe_akses', 'offline');

        if ($request->filled('search')) {
            $query->where('judul', 'like', '%' . $request->search . '%');
        }

        if ($request->filled('kategori')) {
            $query->whereHas('category', function($q) use ($request) {
                $q->where('name', $request->kategori);
            });
        }

        if ($request->filled('tahun')) {
            $query->where('tahun', $request->tahun);
        }

        if ($request->filled('penulis')) {
            $query->where('penulis', $request->penulis);
        }

        $semuaBuku = $query->latest()->get();

        $filterOptions = [
            'kategori' => Category::pluck('name')->unique()->sort()->values(),
            'tahun' => Book::pluck('tahun')->unique()->sortDesc()->values(),
            'penulis' => Book::pluck('penulis')->unique()->sort()->values(),
        ];

        return view('katalog.index', [
            'semuaBuku' => $semuaBuku,
            'filterOptions' => $filterOptions,
            'input' => $request->query(),
            'pageTitle' => 'Peminjaman Buku Offline',
            'mode' => 'offline',
        ]);
    }

    public function ringkasan($id)
    {
        $user = Auth::user();
        $buku = Book::with('category')->findOrFail($id);

        return view('katalog.ringkasan', [
            'user' => $user,
            'buku' => $buku,
            'pageTitle' => 'Peminjaman Buku Offline',
            'actionRoute' => 'peminjaman.form',
            'previousRoute' => 'peminjaman.index',
            'actionButtonText' => 'Lanjutkan ke Form Peminjaman',
            'actionButtonIcon' => 'bi-file-earmark-text-fill',
        ]);
    }

    public function form($id)
    {
        $user = Auth::user();
        $buku = Book::with('category')->findOrFail($id);
        
        $semuaBuku = Book::whereJsonContains('tipe_akses', 'offline')
            ->where('status', 'Tersedia')
            ->get();

        return view('peminjaman.form', compact('user', 'buku', 'semuaBuku'));
    }

    public function store(Request $request)
    {
        $request->validate([
            'buku_ids' => 'required|array|min:1|max:3',
            'buku_ids.*' => 'exists:books,id',
            'tanggal_pinjam' => 'required',
            'tanggal_kembali' => 'required',
        ]);

        $bukuIds = $request->input('buku_ids');
        
        // Parse dates: always today for borrow, and 2 days from now for due date
        $borrowedAt = now();
        $dueAt = now()->addDays(2);

        DB::transaction(function () use ($bukuIds, $borrowedAt, $dueAt) {
            foreach ($bukuIds as $bukuId) {
                $book = Book::lockForUpdate()->find($bukuId);
                
                if ($book->status !== 'Tersedia') {
                    throw new \Exception("Buku '{$book->judul}' sudah tidak tersedia.");
                }

                Loan::create([
                    'user_id' => Auth::id(),
                    'book_id' => $bukuId,
                    'loan_code' => 'PIN-' . date('Ym') . '-' . strtoupper(Str::random(4)) . '-' . $bukuId,
                    'borrowed_at' => $borrowedAt,
                    'due_at' => $dueAt,
                    'status' => 'Dipinjam',
                ]);

                $book->update(['status' => 'Dipinjam']);
            }
        });

        return redirect()->route('dashboard')
            ->with('success', 'Berhasil meminjam ' . count($bukuIds) . ' buku!');
    }
}