<?php

namespace App\Http\Controllers;

use App\Http\Resources\TestResource;
use App\Models\Log;
use App\Models\Test;
use Illuminate\Http\Request;

class TestController extends Controller
{
    const PAGINATION_COUNT = 20;
    private const FIELD_RULES = [
        'title' => 'required|string|max:255',
        'description' => 'required|string',
        'category_id' => 'nullable|exists:categories,id',
        'questions' => 'required|array|min:1',
        'questions.*' => 'exists:questions,id',
        'closed_at' => 'nullable|date',
    ];
    
    /**
     * @OA\Get(
     *     path="/api/tests",
     *     summary="Get a list of tests (paginated)",
     *     description="Retrieve a paginated list of tests. Optionally filter by category_id.",
     *     tags={"Tests"},
     *     @OA\Parameter(
     *         name="category_id",
     *         in="query",
     *         required=false,
     *         description="Filter tests by category ID",
     *         @OA\Schema(type="integer")
     *     ),
     *     @OA\Response(
     *         response=200,
     *         description="Paginated list of tests",
     *         @OA\JsonContent(
     *             type="object",
     *             @OA\Property(
     *                 property="data",
     *                 type="array",
     *                 @OA\Items(ref="#/components/schemas/TestResource")
     *             ),
     *             @OA\Property(
     *                 property="links",
     *                 type="object",
     *                 @OA\Property(property="first", type="string", example="http://api.example.com/tests?page=1"),
     *                 @OA\Property(property="last", type="string", example="http://api.example.com/tests?page=10"),
     *                 @OA\Property(property="prev", type="string", nullable=true, example=null),
     *                 @OA\Property(property="next", type="string", nullable=true, example="http://api.example.com/tests?page=2")
     *             ),
     *             @OA\Property(
     *                 property="meta",
     *                 type="object",
     *                 @OA\Property(property="current_page", type="integer", example=1),
     *                 @OA\Property(property="from", type="integer", example=1),
     *                 @OA\Property(property="last_page", type="integer", example=10),
     *                 @OA\Property(property="path", type="string", example="http://api.example.com/tests"),
     *                 @OA\Property(property="per_page", type="integer", example=15),
     *                 @OA\Property(property="to", type="integer", example=15),
     *                 @OA\Property(property="total", type="integer", example=150)
     *             )
     *         )
     *     ),
     *     @OA\Response(
     *         response=401,
     *         description="Unauthorized"
     *     )
     * )
     */
    public function index(Request $request)
    {
        $query = Test::with(['author', 'category']);

        if ($request->has('category_id')) {
            $query->where('category_id', $request->query('category_id'));
        }

        $questions = $query->paginate(self::PAGINATION_COUNT);

        return TestResource::collection($questions);
    }

    /**
     * @OA\Post(
     *     path="/api/tests",
     *     summary="Create a new test (only admin or creator)",
     *     description="Store a new test in the system (only admin or creator).",
     *     tags={"Tests"},
     *     security={{"bearerAuth":{}}},
     *     @OA\RequestBody(
     *         required=true,
     *         @OA\JsonContent(
     *             required={"title","closed_at","questions"},
     *             @OA\Property(property="title", type="string", maxLength=255, example="Sample Test"),
     *             @OA\Property(property="description", type="string", nullable=true, example="Optional description"),
     *             @OA\Property(property="closed_at", type="string", format="date-time", nullable=true, example="2025-12-01 23:59:59"),
     *             @OA\Property(property="category_id", type="integer", nullable=true, example=3),
     *             @OA\Property(
     *                 property="questions",
     *                 type="array",
     *                 description="Array of question IDs to attach to this test",
     *                 @OA\Items(type="integer", example=1)
     *             )
     *         )
     *     ),
     *     @OA\Response(
     *         response=200,
     *         description="Test created successfully",
     *         @OA\JsonContent(ref="#/components/schemas/TestResource")
     *     ),
     *     @OA\Response(
     *         response=401,
     *         description="Unauthorized"
     *     ),
     *     @OA\Response(
     *         response=422,
     *         description="Validation error"
     *     )
     * )
     */
    public function store(Request $request)
    {
        $this->authorize('create', Test::class);
        $fields = $request->validate(self::FIELD_RULES);

        $fields['author_id'] = $request->user()->id;

        $test = Test::create($fields);
        $test->questions()->sync($fields['questions']);

        $test->load(['category', 'author', 'questions']);
        Log::writeLog("Test '" . $test->title . "' is created by " . $request->user()->username);
        return new TestResource($test);
    }

    /**
     * @OA\Get(
     *     path="/api/tests/{id}",
     *     summary="Get a single test",
     *     description="Retrieve a single test with its questions, category, and author",
     *     tags={"Tests"},
     *     @OA\Parameter(
     *         name="id",
     *         in="path",
     *         required=true,
     *         description="Test ID",
     *         @OA\Schema(type="integer")
     *     ),
     *     @OA\Response(
     *         response=200,
     *         description="Test retrieved successfully",
     *         @OA\JsonContent(ref="#/components/schemas/TestResource")
     *     ),
     *     @OA\Response(
     *         response=404,
     *         description="Test not found"
     *     )
     * )
     */
    public function show(Test $test)
    {
        $test->load(['author', 'category', 'questions']);
        return new TestResource($test);
    }

    /**
     * @OA\Put(
     *     path="/api/tests/{id}",
     *     summary="Update a test (only admin or creator)",
     *     description="Update a test's data and associated questions (only admin/creator).",
     *     tags={"Tests"},
     *     security={{"bearerAuth":{}}},
     *     @OA\Parameter(
     *         name="id",
     *         in="path",
     *         required=true,
     *         description="Test ID",
     *         @OA\Schema(type="integer")
     *     ),
     *     @OA\RequestBody(
     *         required=true,
     *         @OA\JsonContent(
     *             required={"title","questions"},
     *             @OA\Property(property="title", type="string", maxLength=255, example="Updated Test Title"),
     *             @OA\Property(property="description", type="string", nullable=true, example="Optional description"),
     *             @OA\Property(property="category_id", type="integer", nullable=true, example=3),
     *             @OA\Property(property="closed_at", type="string", format="date-time", nullable=true, example="2025-12-01T23:59:59Z"),
     *             @OA\Property(
     *                 property="questions",
     *                 type="array",
     *                 description="Array of question IDs to attach to this test",
     *                 @OA\Items(type="integer", example=1)
     *             )
     *         )
     *     ),
     *     @OA\Response(
     *         response=200,
     *         description="Test updated successfully",
     *         @OA\JsonContent(ref="#/components/schemas/TestResource")
     *     ),
     *     @OA\Response(
     *         response=401,
     *         description="Unauthorized"
     *     ),
     *     @OA\Response(
     *         response=422,
     *         description="Validation error"
     *     )
     * )
     */
    public function update(Request $request, Test $test)
    {
        $this->authorize('update', $test);
        $fields = $request->validate(self::FIELD_RULES);

        $test->update($fields);
        $test->questions()->sync($fields['questions']);

        Log::writeLog("Test '" . $test->title . "' is updated by " . $request->user()->username);

        $test->load(['category', 'author', 'questions']);
        return new TestResource($test);
    }

    /**
     * @OA\Delete(
     *     path="/api/tests/{id}",
     *     summary="Delete a test (only admin or creator)",
     *     description="Delete a test by ID (only admin or creator).",
     *     tags={"Tests"},
     *     security={{"bearerAuth":{}}},
     *     @OA\Parameter(
     *         name="id",
     *         in="path",
     *         required=true,
     *         description="Test ID",
     *         @OA\Schema(type="integer")
     *     ),
     *     @OA\Response(
     *         response=200,
     *         description="Test deleted successfully",
     *         @OA\JsonContent(
     *             type="object",
     *             @OA\Property(property="message", type="string", example="The test was deleted")
     *         )
     *     ),
     *     @OA\Response(
     *         response=401,
     *         description="Unauthorized"
     *     ),
     *     @OA\Response(
     *         response=404,
     *         description="Test not found"
     *     )
     * )
     */
    public function destroy(Request $request, Test $test)
    {
        $this->authorize('delete', $test);
        $test->delete();
        Log::writeLog("Test '" . $test->title . "' is deleted by " . $request->user()->username);

        return ['message' => 'The hitcount was deleted'];
    }
}