<?php

namespace Espo\Custom\Api\JunctionData;

use Espo\Core\Api\Action;
use Espo\Core\Api\Request;
use Espo\Core\Api\Response;
use Espo\Core\Api\ResponseComposer;
use Espo\Core\Exceptions\BadRequest;
use Espo\Core\Exceptions\Conflict;
use Espo\Core\Exceptions\NotFound;
use Espo\ORM\EntityManager;

/**
 * POST /api/v1/JunctionData/CAdvowareAkten/:akteId/dokumentes/:documentId
 * 
 * Links a document to an Akte and sets junction table columns in one operation
 */
class LinkAktenDokument implements Action
{
    public function __construct(
        private EntityManager $entityManager
    ) {}
    
    public function process(Request $request): Response
    {
        $akteId = $request->getRouteParam('akteId');
        $documentId = $request->getRouteParam('documentId');
        $data = $request->getParsedBody();
        
        if (!$akteId || !$documentId) {
            throw new BadRequest('Akte ID and Document ID are required');
        }
        
        // Verify entities exist
        $akte = $this->entityManager->getEntityById('CAdvowareAkten', $akteId);
        if (!$akte) {
            throw new NotFound('Akte not found');
        }
        
        $document = $this->entityManager->getEntityById('CDokumente', $documentId);
        if (!$document) {
            throw new NotFound('Document not found');
        }
        
        // Check if already linked
        if ($this->checkIfLinked($akteId, $documentId)) {
            // Already linked, just update junction columns
            return $this->updateExisting($akteId, $documentId, $data);
        }
        
        // Create relationship via ORM (triggers hooks)
        $this->entityManager
            ->getRDBRepository('CAdvowareAkten')
            ->getRelation($akte, 'dokumentes')
            ->relate($document);
        
        // Then update junction columns via SQL (no hooks)
        return $this->updateExisting($akteId, $documentId, $data);
    }
    
    private function checkIfLinked(string $akteId, string $documentId): bool
    {
        $pdo = $this->entityManager->getPDO();
        
        $sql = "
            SELECT COUNT(*) as count
            FROM c_advoware_akten_dokumente
            WHERE c_advoware_akten_id = :akteId
              AND c_dokumente_id = :documentId
              AND deleted = 0
        ";
        
        $sth = $pdo->prepare($sql);
        $sth->execute([
            'akteId' => $akteId,
            'documentId' => $documentId
        ]);
        
        $result = $sth->fetch(\PDO::FETCH_ASSOC);
        return $result['count'] > 0;
    }
    
    private function updateExisting(string $akteId, string $documentId, object $data): Response
    {
        $pdo = $this->entityManager->getPDO();
        
        // Build dynamic UPDATE
        $setClauses = [];
        $params = [
            'akteId' => $akteId,
            'documentId' => $documentId
        ];
        
        if (isset($data->hnr)) {
            if (!is_numeric($data->hnr)) {
                throw new BadRequest('hnr must be a number');
            }
            $setClauses[] = "hnr = :hnr";
            $params['hnr'] = (int)$data->hnr;
        }
        
        if (isset($data->syncstatus)) {
            $allowedStatuses = ['new', 'unclean', 'synced', 'failed', 'unsupported'];
            if (!in_array($data->syncstatus, $allowedStatuses)) {
                throw new BadRequest('Invalid syncstatus. Allowed: ' . implode(', ', $allowedStatuses));
            }
            $setClauses[] = "syncstatus = :syncstatus";
            $params['syncstatus'] = $data->syncstatus;
        }
        
        if (isset($data->lastSync)) {
            $setClauses[] = "last_sync = :lastSync";
            $params['lastSync'] = $data->lastSync;
        } elseif (isset($data->updateLastSync) && $data->updateLastSync === true) {
            $setClauses[] = "last_sync = NOW()";
        }
        
        if (!empty($setClauses)) {
            $sql = "
                UPDATE c_advoware_akten_dokumente
                SET " . implode(', ', $setClauses) . "
                WHERE c_advoware_akten_id = :akteId
                  AND c_dokumente_id = :documentId
                  AND deleted = 0
            ";
            
            $sth = $pdo->prepare($sql);
            $sth->execute($params);
        }
        
        // Return final junction entry
        $sql = "
            SELECT 
                id as junctionId,
                c_advoware_akten_id as cAdvowareAktenId,
                c_dokumente_id as cDokumenteId,
                hnr,
                syncstatus,
                last_sync as lastSync
            FROM c_advoware_akten_dokumente
            WHERE c_advoware_akten_id = :akteId
              AND c_dokumente_id = :documentId
              AND deleted = 0
        ";
        
        $sth = $pdo->prepare($sql);
        $sth->execute([
            'akteId' => $akteId,
            'documentId' => $documentId
        ]);
        
        $result = $sth->fetch(\PDO::FETCH_ASSOC);
        
        if (!$result) {
            throw new NotFound('Junction entry not found after creation');
        }
        
        return ResponseComposer::json($result);
    }
}