<?php

namespace App\Node;

use App\Exceptions\BadRequestException;
use App\Node\UseCases\BulkCreateNodesRequest;
use App\Node\NodeRepository;
use App\Node\UseCases\BulkCreateNodes;
use App\Node\UseCases\CreateNode;
use App\Node\UseCases\CreateNodeRequest;
use App\Text\Text;
use App\Text\TextRepository;
use App\User\User;
use DomainException;
use Psr\Http\Message\ResponseInterface as Response;
use Psr\Http\Message\ServerRequestInterface as Request;

class NodeController
{
    public function __construct(
        private NodeRepository $nodeRepository,
        private TextRepository $textRepository,
    ) {}

    public function getNodesOfText(
        Request $request,
        Response $response,
        int $textId,
    ): Response {
        $user = $request->getAttribute('user');
        if (!$user instanceof User) {
            return $this->errorResponse(
                $response,
                401,
                'unauthenticated'
            );
        }

        $text = $this->textRepository->find($textId);

        if ($text === null) {
            return $response->withStatus(404);
        }

        if (!$this->userMayAccessText($user, $text)) {
            return $this->errorResponse(
                $response,
                403,
                'forbidden'
            );
        }

        $nodes = $this->nodeRepository->findByTextId($textId);

        $data = array_map(function ($node) {
            return [
                'id' => $node->getId(),
                'title' => $node->getTitle(),
                'parentNodeId' => $node->getParentNode()?->getId(),
            ];
        }, $nodes);

        $response->getBody()->write(json_encode(array_values($data)));
        return $response->withHeader('Content-Type', 'application/json');
    }

    public function createNode(
        Request $request,
        Response $response,
        CreateNode $createNodeUseCase,
    ): Response {
        $user = $request->getAttribute('user');
        if (!$user instanceof User) {
            return $this->errorResponse(
                $response,
                401,
                'unauthenticated'
            );
        }

        $data = json_decode((string) $request->getBody(), true) ?? [];

        $textId = isset($data['textId']) ? (int) $data['textId'] : null;
        $title = $data['title'] ?? null;
        $parentNodeId = isset($data['parentNodeId']) ? (int) $data['parentNodeId'] : null;

        if ($textId !== null) {
            $ownershipResponse = $this->checkTextOwnership(
                $user,
                $textId,
                $response,
            );
            if ($ownershipResponse !== null) {
                return $ownershipResponse;
            }
        }

        try {
            $node = $createNodeUseCase->execute(new CreateNodeRequest(
                textId: $textId,
                title: $title,
                parentNodeId: $parentNodeId,
            ));
        } catch (BadRequestException $e) {
            $response->getBody()->write(json_encode(['error' => $e->getMessage()]));
            return $response->withStatus(400)->withHeader('Content-Type', 'application/json');
        } catch (DomainException $e) {
            $response->getBody()->write(json_encode(['error' => $e->getMessage()]));
            return $response->withStatus(404)->withHeader('Content-Type', 'application/json');
        }

        $response->getBody()->write(json_encode([
            'id' => $node->getId(),
            'title' => $node->getTitle(),
            'parentNodeId' => $node->getParentNode()?->getId(),
        ]));
        return $response->withStatus(201)->withHeader('Content-Type', 'application/json');
    }

    public function bulkCreateNodes(
        Request $request,
        Response $response,
        BulkCreateNodes $bulkCreateNodesUseCase,
    ): Response {
        $user = $request->getAttribute('user');
        if (!$user instanceof User) {
            return $this->errorResponse(
                $response,
                401,
                'unauthenticated'
            );
        }

        $data = json_decode((string) $request->getBody(), true) ?? [];

        $textId = isset($data['textId']) ? (int) $data['textId'] : null;
        $parentNodeId = isset($data['parentNodeId']) ? (int) $data['parentNodeId'] : null;
        $titlePrefix = isset($data['titlePrefix']) ? (string) $data['titlePrefix'] : null;
        $count = isset($data['count']) ? (int) $data['count'] : null;

        if ($textId !== null) {
            $ownershipResponse = $this->checkTextOwnership(
                $user,
                $textId,
                $response,
            );
            if ($ownershipResponse !== null) {
                return $ownershipResponse;
            }
        }

        try {
            $nodes = $bulkCreateNodesUseCase->execute(new BulkCreateNodesRequest(
                textId: $textId,
                parentNodeId: $parentNodeId,
                titlePrefix: $titlePrefix,
                count: $count,
            ));
        } catch (BadRequestException $e) {
            $response->getBody()->write(json_encode(['error' => $e->getMessage()]));
            return $response->withStatus(400)->withHeader('Content-Type', 'application/json');
        } catch (DomainException $e) {
            $response->getBody()->write(json_encode(['error' => $e->getMessage()]));
            return $response->withStatus(404)->withHeader('Content-Type', 'application/json');
        }

        $result = array_map(function ($node) {
            return [
                'id' => $node->getId(),
                'title' => $node->getTitle(),
                'parentNodeId' => $node->getParentNode()?->getId(),
            ];
        }, $nodes);

        $response->getBody()->write(json_encode(array_values($result)));
        return $response->withStatus(201)->withHeader('Content-Type', 'application/json');
    }

    private function checkTextOwnership(
        User $user,
        int $textId,
        Response $response,
    ): ?Response {
        $text = $this->textRepository->find($textId);
        if ($text === null) {
            return null;
        }
        if (!$this->userMayAccessText($user, $text)) {
            return $this->errorResponse(
                $response,
                403,
                'forbidden'
            );
        }
        return null;
    }

    private function userMayAccessText(User $user, Text $text): bool
    {
        if ($user->isAdmin()) {
            return true;
        }
        return $text->getUser()->getId() === $user->getId();
    }

    private function errorResponse(
        Response $response,
        int $status,
        string $message,
    ): Response {
        $response->getBody()->write(
            json_encode(['error' => $message])
        );

        return $response->withStatus($status)
            ->withHeader('Content-Type', 'application/json');
    }
}