<?php

namespace App\Http\Controllers\Api\Tenant;

use App\Http\Controllers\Controller;
use App\Http\Requests\Tenant\TaskStoreRequest;
use App\Http\Requests\Tenant\TaskUpdateRequest;
use App\Http\Resources\Tenant\TaskResource;
use App\Models\Task;
use App\Models\TaskCollection;
use App\Models\Event;
use Illuminate\Http\Request;
use Illuminate\Http\Resources\Json\AnonymousResourceCollection;
use Illuminate\Http\JsonResponse;

class TaskController extends Controller
{
    /**
     * Display a listing of the tenant's tasks.
     *
     * @param Request $request
     * @return AnonymousResourceCollection
     */
    public function index(Request $request): AnonymousResourceCollection
    {
        $query = Task::where('tenant_id', $request->tenant->id)
            ->with(['taskCollection', 'assignedEvents'])
            ->orderBy('created_at', 'desc');

        // Search and filters
        if ($search = $request->get('search')) {
            $query->where('title', 'like', "%{$search}%")
                  ->orWhere('description', 'like', "%{$search}%");
        }

        if ($collectionId = $request->get('collection_id')) {
            $query->whereHas('taskCollection', fn($q) => $q->where('id', $collectionId));
        }

        if ($eventId = $request->get('event_id')) {
            $query->whereHas('assignedEvents', fn($q) => $q->where('id', $eventId));
        }

        $perPage = $request->get('per_page', 15);
        $tasks = $query->paginate($perPage);

        return TaskResource::collection($tasks);
    }

    /**
     * Store a newly created task in storage.
     *
     * @param TaskStoreRequest $request
     * @return JsonResponse
     */
    public function store(TaskStoreRequest $request): JsonResponse
    {
        $task = Task::create(array_merge($request->validated(), [
            'tenant_id' => $request->tenant->id,
        ]));

        if ($collectionId = $request->input('collection_id')) {
            $task->taskCollection()->associate(TaskCollection::findOrFail($collectionId));
            $task->save();
        }

        $task->load(['taskCollection', 'assignedEvents']);

        return response()->json([
            'message' => 'Task erfolgreich erstellt.',
            'data' => new TaskResource($task),
        ], 201);
    }

    /**
     * Display the specified task.
     *
     * @param Request $request
     * @param Task $task
     * @return JsonResponse
     */
    public function show(Request $request, Task $task): JsonResponse
    {
        if ($task->tenant_id !== $request->tenant->id) {
            abort(404, 'Task nicht gefunden.');
        }

        $task->load(['taskCollection', 'assignedEvents']);

        return response()->json(new TaskResource($task));
    }

    /**
     * Update the specified task in storage.
     *
     * @param TaskUpdateRequest $request
     * @param Task $task
     * @return JsonResponse
     */
    public function update(TaskUpdateRequest $request, Task $task): JsonResponse
    {
        if ($task->tenant_id !== $request->tenant->id) {
            abort(404, 'Task nicht gefunden.');
        }

        $task->update($request->validated());

        if ($collectionId = $request->input('collection_id')) {
            $task->taskCollection()->associate(TaskCollection::findOrFail($collectionId));
            $task->save();
        }

        $task->load(['taskCollection', 'assignedEvents']);

        return response()->json([
            'message' => 'Task erfolgreich aktualisiert.',
            'data' => new TaskResource($task),
        ]);
    }

    /**
     * Remove the specified task from storage.
     *
     * @param Request $request
     * @param Task $task
     * @return JsonResponse
     */
    public function destroy(Request $request, Task $task): JsonResponse
    {
        if ($task->tenant_id !== $request->tenant->id) {
            abort(404, 'Task nicht gefunden.');
        }

        $task->delete();

        return response()->json([
            'message' => 'Task erfolgreich gelöscht.',
        ]);
    }

    /**
     * Assign task to an event.
     *
     * @param Request $request
     * @param Task $task
     * @param Event $event
     * @return JsonResponse
     */
    public function assignToEvent(Request $request, Task $task, Event $event): JsonResponse
    {
        if ($task->tenant_id !== $request->tenant->id || $event->tenant_id !== $request->tenant->id) {
            abort(404);
        }

        if ($task->assignedEvents()->where('event_id', $event->id)->exists()) {
            return response()->json(['message' => 'Task ist bereits diesem Event zugewiesen.'], 409);
        }

        $task->assignedEvents()->attach($event->id);

        return response()->json([
            'message' => 'Task erfolgreich dem Event zugewiesen.',
        ]);
    }

    /**
     * Bulk assign tasks to an event.
     *
     * @param Request $request
     * @param Event $event
     * @return JsonResponse
     */
    public function bulkAssignToEvent(Request $request, Event $event): JsonResponse
    {
        if ($event->tenant_id !== $request->tenant->id) {
            abort(404);
        }

        $taskIds = $request->input('task_ids', []);
        if (empty($taskIds)) {
            return response()->json(['error' => 'Keine Task-IDs angegeben.'], 400);
        }

        $tasks = Task::whereIn('id', $taskIds)
            ->where('tenant_id', $request->tenant->id)
            ->get();

        $attached = 0;
        foreach ($tasks as $task) {
            if (!$task->assignedEvents()->where('event_id', $event->id)->exists()) {
                $task->assignedEvents()->attach($event->id);
                $attached++;
            }
        }

        return response()->json([
            'message' => "{$attached} Tasks dem Event zugewiesen.",
        ]);
    }

    /**
     * Get tasks for a specific event.
     *
     * @param Request $request
     * @param Event $event
     * @return AnonymousResourceCollection
     */
    public function forEvent(Request $request, Event $event): AnonymousResourceCollection
    {
        if ($event->tenant_id !== $request->tenant->id) {
            abort(404);
        }

        $tasks = Task::whereHas('assignedEvents', fn($q) => $q->where('event_id', $event->id))
            ->with(['taskCollection'])
            ->orderBy('created_at', 'desc')
            ->paginate($request->get('per_page', 15));

        return TaskResource::collection($tasks);
    }

    /**
     * Get tasks from a specific collection.
     *
     * @param Request $request
     * @param TaskCollection $collection
     * @return AnonymousResourceCollection
     */
    public function fromCollection(Request $request, TaskCollection $collection): AnonymousResourceCollection
    {
        if ($collection->tenant_id !== $request->tenant->id) {
            abort(404);
        }

        $tasks = $collection->tasks()
            ->with(['assignedEvents'])
            ->orderBy('created_at', 'desc')
            ->paginate($request->get('per_page', 15));

        return TaskResource::collection($tasks);
    }
}