<?php

namespace Modules\M3\Http\Controllers\API;

use Cache;
use Config;
use File;
use Illuminate\Http\JsonResponse;
use Illuminate\Http\Request;
use Modules\M3\Helpers\Helper;
use Modules\M3\Http\Controllers\Controller;
use Str;

class PdfStorage extends Controller
{
    private const ZERO_PAD = '000000';

    public function PdfStorageAPI(Request $request): JsonResponse
    {
        $this->configureTimeouts();
        $context = $this->requestContext($request);

        if ($context === null) {
            $result = $this->errorResponse('No URL Parameters Sent', self::ZERO_PAD, '', '', '');
        } else {
            try {
                $this->logRequest($context);
                $cacheKey = $this->buildCacheKey($context);
                $pdfFileName = (string) Config::get('arrays.PdfPath') . $context['FILENAME'] . '.pdf';
                $error = $this->validateStorageRequest($pdfFileName, $cacheKey);

                if ($error !== null) {
                    $result = $this->errorResponse($error, $context['DELIVERYNO'], $context['DOCNUM'], $context['COMPANY'], $context['WHS']);
                } else {
                    Cache::forever($cacheKey, base64_encode(File::get($pdfFileName)));
                    $this->logResult($context, 'PDF File converted to Base64 and Saved to Cache.Key: ' . $cacheKey);
                    $result = response()->json(['code' => '200', 'status' => 'Success', 'cacheKey' => $cacheKey]);
                }
            } catch (\Throwable $exception) {
                $message = 'An Error Occured - ' . substr($exception->getMessage(), 0, 300);
                $this->safeLog($context, $message, true);
                $result = response()->json([
                    'code' => '405',
                    'status' => 'error',
                    'message' => 'Catched Error: ' . $exception->getMessage(),
                ]);
            }
        }

        return $result;
    }

    private function configureTimeouts(): void
    {
        $timeout = (string) Config::get('arrays.PHPTimeOut');
        ini_set('max_execution_time', $timeout);
        ini_set('max_input_time', $timeout);
        ini_set('default_socket_timeout', $timeout);
    }

    private function requestContext(Request $request): ?array
    {
        if ($request->all() === []) {
            return null;
        }

        $context = [];
        foreach (['COMPANY', 'WHS', 'DOCTYPE', 'FILENAME', 'DOCNUM', 'A4MACPKR'] as $key) {
            $context[$key] = trim((string) $request->input($key, ''));
        }

        $context['DELIVERYNO'] = $context['A4MACPKR'] !== '' ? $context['A4MACPKR'] : self::ZERO_PAD;
        $context['SHUSER'] = m3User() !== '' ? Str::upper(m3User()) : 'WebUser';
        $context['SHSOURCE'] = 'PdfStorageAPI';

        return $context;
    }

    private function buildCacheKey(array $context): string
    {
        foreach (['A4MACPKR', 'DOCTYPE', 'DOCNUM', 'COMPANY', 'WHS'] as $required) {
            if ($context[$required] === '') {
                return '';
            }
        }

        return $context['A4MACPKR'] . $context['DOCTYPE'] . $context['DOCNUM'] . $context['COMPANY'] . $context['WHS'];
    }

    private function validateStorageRequest(string $pdfFileName, string $cacheKey): ?string
    {
        $messages = [];
        if (! File::exists($pdfFileName)) {
            $messages[] = 'PDF File Not Found-';
        }
        if ($cacheKey === '') {
            $messages[] = 'Cache Key is missing Params';
        }

        return $messages === [] ? null : implode('', $messages);
    }

    private function logRequest(array $context): void
    {
        $params = array_intersect_key($context, array_flip(['COMPANY', 'WHS', 'DOCTYPE', 'FILENAME', 'A4MACPKR', 'DOCNUM']));
        $this->safeLog($context, json_encode($params, JSON_THROW_ON_ERROR), false, 'M3-Req-out');
    }

    private function logResult(array $context, string $message): void
    {
        $this->safeLog($context, $message);
    }

    private function safeLog(array $context, string $message, bool $error = false, string $type = 'M3-Res-out'): void
    {
        try {
            Helper::logToICM699M([
                'SHMACPKR' => $context['DELIVERYNO'] ?? self::ZERO_PAD,
                'SHDT' => date('Y-m-d'),
                'SHTIME' => date('H:i:s'),
                'SHERROR' => $error ? 'X' : '',
                'SHINTBOX' => $context['DOCNUM'] ?? '',
                'SHTYPE' => $type,
                'SHDATA' => $message,
                'SHUSER' => $context['SHUSER'] ?? (m3User() !== '' ? Str::upper(m3User()) : 'WebUser'),
                'SHSOURCE' => $context['SHSOURCE'] ?? 'PdfStorageAPI',
                'SHCO' => $context['COMPANY'] ?? '',
                'SHWHS' => $context['WHS'] ?? '',
            ]);
        } catch (\Throwable) {
            // Logging must never turn an API response into a 500 error.
        }
    }

    private function errorResponse(string $message, string $deliveryNo, string $docNum, string $company, string $warehouse): JsonResponse
    {
        $context = [
            'DELIVERYNO' => $deliveryNo,
            'DOCNUM' => $docNum,
            'COMPANY' => $company,
            'WHS' => $warehouse,
            'SHUSER' => m3User() !== '' ? Str::upper(m3User()) : 'WebUser',
            'SHSOURCE' => 'PdfStorageAPI',
        ];
        $this->safeLog($context, 'An Error Occured -' . $message, true);

        return response()->json(['code' => '405', 'status' => 'Error', 'message' => $message]);
    }
}