<?php

namespace App\Http\Controllers\Api;

use App\Helpers\Helper;
use App\Http\Controllers\Controller;
use App\Http\Requests\ItemImportRequest;
use App\Http\Transformers\ImportsTransformer;
use App\Models\Asset;
use App\Models\Company;
use App\Models\Import;
use Artisan;
use Illuminate\Support\Facades\Request;
use Illuminate\Support\Facades\Session;
use Illuminate\Support\Facades\Storage;
use League\Csv\Reader;
use Symfony\Component\HttpFoundation\File\Exception\FileException;

class ImportController extends Controller
{
    /**
     * Display a listing of the resource.
     *
     * @return \Illuminate\Http\Response
     */
    public function index()
    {
        $this->authorize('import');
        $imports = Import::latest()->get();

        return (new ImportsTransformer)->transformImports($imports);
    }

    /**
     * Process and store a CSV upload file.
     *
     * @param  \Illuminate\Http\Request  $request
     * @return \Illuminate\Http\Response
     */
    public function store()
    {
        $this->authorize('import');
        if (! config('app.lock_passwords')) {
            $files = Request::file('files');
            $path = config('app.private_uploads').'/imports';
            $results = [];
            $import = new Import;
            foreach ($files as $file) {
                if (! in_array($file->getMimeType(), [
                    'application/vnd.ms-excel',
                    'text/csv',
                    'application/csv',
                    'text/x-Algol68', // because wtf CSV files?
                    'text/plain',
                    'text/comma-separated-values',
                    'text/tsv', ])) {
                    $results['error'] = 'File type must be CSV. Uploaded file is '.$file->getMimeType();

                    return response()->json(Helper::formatStandardApiResponse('error', null, $results['error']), 500);
                }

                //TODO: is there a lighter way to do this?
                if (! ini_get('auto_detect_line_endings')) {
                    ini_set('auto_detect_line_endings', '1');
                }
                $reader = Reader::createFromFileObject($file->openFile('r')); //file pointer leak?
                $import->header_row = $reader->fetchOne(0);

                //duplicate headers check
                $duplicate_headers = [];

                for ($i = 0; $i < count($import->header_row); $i++) {
                    $header = $import->header_row[$i];
                    if (in_array($header, $import->header_row)) {
                        $found_at = array_search($header, $import->header_row);
                        if ($i > $found_at) {
                            //avoid reporting duplicates twice, e.g. "1 is same as 17! 17 is same as 1!!!"
                            //as well as "1 is same as 1!!!" (which is always true)
                            //has to be > because otherwise the first result of array_search will always be $i itself(!)
                            array_push($duplicate_headers, "Duplicate header '$header' detected, first at column: ".($found_at + 1).', repeats at column: '.($i + 1));
                        }
                    }
                }
                if (count($duplicate_headers) > 0) {
                    return response()->json(Helper::formatStandardApiResponse('error', null, implode('; ', $duplicate_headers)), 500); //should this be '4xx'?
                }

                // Grab the first row to display via ajax as the user picks fields
                $import->first_row = $reader->fetchOne(1);

                $date = date('Y-m-d-his');
                $fixed_filename = str_slug($file->getClientOriginalName());
                try {
                    $file->move($path, $date.'-'.$fixed_filename);
                } catch (FileException $exception) {
                    $results['error'] = trans('admin/hardware/message.upload.error');
                    if (config('app.debug')) {
                        $results['error'] .= ' '.$exception->getMessage();
                    }

                    return response()->json(Helper::formatStandardApiResponse('error', null, $results['error']), 500);
                }
                $file_name = date('Y-m-d-his').'-'.$fixed_filename;
                $import->file_path = $file_name;
                $import->filesize = filesize($path.'/'.$file_name);
                $import->save();
                $results[] = $import;
            }
            $results = (new ImportsTransformer)->transformImports($results);

            return [
                'files' => $results,
            ];
        }

        return response()->json(Helper::formatStandardApiResponse('error', null, trans('general.feature_disabled')), 500);
    }

    /**
     * Processes the specified Import.
     *
     * @param  int  $import_id
     * @return \Illuminate\Http\Response
     */
    public function process(ItemImportRequest $request, $import_id)
    {
        $this->authorize('import');

        // Run a backup immediately before processing
        if ($request->has('run-backup')) {
            \Log::debug('Backup manually requested via importer');
            Artisan::call('backup:run');
        } else {
            \Log::debug('NO BACKUP requested via importer');
        }

        $import = Import::find($import_id);

        if(is_null($import)){
            $error[0][0] = trans("validation.exists", ["attribute" => "file"]);
            return response()->json(Helper::formatStandardApiResponse('import-errors', null, $error), 500);
        }

        $errors = $request->import($import);
        $redirectTo = 'hardware.index';
        switch ($request->get('import-type')) {
            case 'asset':
                $redirectTo = 'hardware.index';
                break;
            case 'accessory':
                $redirectTo = 'accessories.index';
                break;
            case 'consumable':
                $redirectTo = 'consumables.index';
                break;
            case 'component':
                $redirectTo = 'components.index';
                break;
            case 'license':
                $redirectTo = 'licenses.index';
                break;
            case 'user':
                $redirectTo = 'users.index';
                break;
        }

        if ($errors) { //Failure
            return response()->json(Helper::formatStandardApiResponse('import-errors', null, $errors), 500);
        }
        //Flash message before the redirect
        Session::flash('success', trans('admin/hardware/message.import.success'));

        return response()->json(Helper::formatStandardApiResponse('success', null, ['redirect_url' => route($redirectTo)]));
    }

    /**
     * Remove the specified resource from storage.
     *
     * @param  int  $import_id
     * @return \Illuminate\Http\Response
     */
    public function destroy($import_id)
    {
        $this->authorize('create', Asset::class);

        if ($import = Import::find($import_id)) {
            try {
                // Try to delete the file
                Storage::delete('imports/'.$import->file_path);
                $import->delete();

                return response()->json(Helper::formatStandardApiResponse('success', null, trans('admin/hardware/message.import.file_delete_success')));
            } catch (\Exception $e) {
                // If the file delete didn't work, remove it from the database anyway and return a warning
                $import->delete();

                return response()->json(Helper::formatStandardApiResponse('warning', null, trans('admin/hardware/message.import.file_not_deleted_warning')));
            }
        }
    }
}