<?php

declare(strict_types=1);

namespace App\Http\Controllers;

use App\Models\BrandContract;
use App\Models\Client;
use App\Models\ClientCategory;
use Illuminate\Http\JsonResponse;
use Illuminate\Http\RedirectResponse;
use Illuminate\Http\Request;
use Illuminate\View\View;

class BrandContractController extends Controller
{
    private function categoryTree(): \Illuminate\Support\Collection
    {
        return ClientCategory::with('children')
            ->whereNull('parent_id')
            ->orderBy('sort_order')
            ->get();
    }

    public function index(): View
    {
        $contracts    = BrandContract::with(['client', 'category'])
            ->orderByDesc('end_date')
            ->get();
        $clients      = Client::orderBy('name')->get();
        $categoryTree = $this->categoryTree();

        return view('contracts.index', compact('contracts', 'clients', 'categoryTree'));
    }

    public function store(Request $request): RedirectResponse
    {
        $validated = $request->validate([
            'title'       => 'required|string|max:255',
            'client_id'   => 'nullable|exists:clients,id',
            'category_id' => 'required|exists:client_categories,id',
            'start_date'  => 'required|date',
            'end_date'    => 'required|date|after_or_equal:start_date',
            'notes'       => 'nullable|string',
        ]);

        $validated['is_active'] = true;
        BrandContract::create($validated);

        return back()->with('success', '📝 Contract added!');
    }

    public function update(Request $request, BrandContract $contract): RedirectResponse
    {
        $validated = $request->validate([
            'title'       => 'required|string|max:255',
            'client_id'   => 'nullable|exists:clients,id',
            'category_id' => 'required|exists:client_categories,id',
            'start_date'  => 'required|date',
            'end_date'    => 'required|date|after_or_equal:start_date',
            'notes'       => 'nullable|string',
            'is_active'   => 'boolean',
        ]);

        $validated['is_active'] = $request->boolean('is_active', $contract->is_active);
        $contract->update($validated);

        return back()->with('success', '📝 Contract updated!');
    }

    public function destroy(BrandContract $contract): RedirectResponse
    {
        $contract->delete();
        return back()->with('success', '📝 Contract removed.');
    }

    public function toggle(BrandContract $contract): RedirectResponse
    {
        $contract->update(['is_active' => ! $contract->is_active]);
        return back()->with('success', $contract->is_active ? '✅ Contract activated.' : '⏸️ Contract paused.');
    }

    /**
     * AJAX: check if a category has an active exclusive contract.
     * Returns null if clear, or contract details if blocked.
     */
    public function check(Request $request): JsonResponse
    {
        $categoryId = $request->integer('category_id');
        $clientId   = $request->integer('client_id');

        if (! $categoryId) {
            return response()->json(null);
        }

        // Collect the category and its parent chain (so blocking a parent also blocks children)
        $category   = ClientCategory::find($categoryId);
        $checkIds   = [$categoryId];
        if ($category?->parent_id) {
            $checkIds[] = $category->parent_id;
        }

        $contract = BrandContract::with(['client', 'category'])
            ->active()
            ->whereIn('category_id', $checkIds)
            ->first();

        if (! $contract) {
            return response()->json(null);
        }

        // Allow if it's the contracted brand itself
        if ($clientId && $contract->client_id && $contract->client_id === $clientId) {
            return response()->json(null);
        }

        return response()->json([
            'id'           => $contract->id,
            'title'        => $contract->title,
            'client_name'  => $contract->client?->name ?? 'Unknown',
            'category'     => $contract->category?->name ?? 'Unknown',
            'end_date'     => $contract->end_date->format('d M Y'),
            'days_left'    => $contract->days_remaining,
        ]);
    }
}