<?php

namespace App\Http\Controllers;

use App\Filters\FileFilters;
use App\Helpers\LengthFormatter;
use App\Models\File;
use App\Models\SmartBlock;
use App\Models\SmartBlockContent;
use App\Models\SmartBlockCriteria;
use DateInterval;
use DateTime;
use Illuminate\Http\Request;
use Illuminate\Support\Collection;
use Illuminate\Support\Facades\Auth;

class SmartBlockController extends Controller
{

    /**
     * Retrieve a list of smart blocks, with optional filters,
     * defined in app/Filters/FileFilters
     * @return string
     */
    public function index(FileFilters $filters) {
        if (!isset($filters->per_page) || is_null($filters)) {
            $pagination = 20;
        } else {
            $pagination = $filters->per_page;
        }
        return File::filter($filters)->cursorPaginate($pagination)->toJson();
    }

    /**
     * Method used to store a new smart block
     * @param Request $request
     * @return mixed
     */
    public function store(Request $request) {
        return $this->save($request);
    }

    /**
     * Method used to update a smart block
     * @param Request $request
     * @param $id
     * @return mixed
     */
    public function update(Request $request, $id) {
        return $this->save($request, $id);
    }

    /**
     * Delete a smart block, cleaning also cc_blockcontent and cc_blockcriteria
     * @param $id
     * @return int
     */
    public function delete($id) {
        return SmartBlock::with(['content', 'criteria'])::destroy($id);
    }

    /**
     * Save a new or updated smart block, with content and criteria
     * @param Request $request
     * @param $id
     * @return mixed string
     */
    public function save(Request $request, $id = null) {
        $user = Auth::user();
        $request->validate([
            'name' => 'required|string',
            'type' => 'required|string',
            'length' => 'required|string',
            'length_type' => 'required|string',
            'criteria' => 'required|array'
        ]);

        $criteria = $request->criteria;
        $length = ($request->length_type == 'time') ? new LengthFormatter($request->length) : null;

         $dbSmartBlock = SmartBlock::firstOrNew(['id' => $id]);
         $dbSmartBlock->fill(new Request([
             'name' => $request->name,
             'creator_id' => $user->id,
             'description' => $request->description,
             'length' => $length,
         ]));

         $this->saveCriteria($dbSmartBlock, $criteria);

         return $dbSmartBlock->with('criteria')->with('content')->get()->toJson();
    }

    /**
     * Save Smart Block Criteria to database
     * @param SmartBlock $smartBlock
     * @param array $criteria
     * @return void
     */
    private function saveCriteria(SmartBlock $smartBlock, array $criteria): void {
        $ids = [];
        foreach($criteria as $criterion) {
            $ids[] = SmartBlockCriteria::updateOrCreate([
                'criteria' => $criterion['name'],
                'block_id' => $smartBlock->id,
            ],
                [
                    'modifier' => $criterion['modifier'],
                    'value' => $criterion['value'],
                    'extra' => $criterion['extra'], //ToDo: understand this field
                    'criteriagroup' => $criterion['criteriagroup'],
                ]);
        }
        if (!empty($ids)) {
            SmartBlockCriteria::whereNotIn('id', $ids)->delete();
        }
    }

    /**
     * @param int $block_id
     * @param int|null $instance_id
     * @return mixed json string
     * @throws \DateMalformedIntervalStringException
     */
    public function getTrackList(int $block_id, int $instance_id = null) {
        $smartBlock = SmartBlock::whereId($block_id)->first();
        $criteria = $smartBlock->criteria;
        $files = File::smartBlockFilter($criteria)->get();

        return $this->criteriaLimit($criteria, $files);
    }

    /**
     * Loop through files if limit criteria is based on total length and stop
     * to loop when total length is reached
     * @param Collection $criteria
     * @param Collection $files
     * @return mixed json string
     * @throws \DateMalformedIntervalStringException
     */
    private function criteriaLimit(Collection $criteria, Collection $files) {
        $limit = $criteria->where('criteria', 'limit')->first();
        $overflow = $criteria->where('criteria', 'overflow_tracks')->first()->value;

        //If limit is not based on sum tracks length is already done in query by filters
        if (is_null($limit) || !in_array($limit->modifier, ['hours', 'minutes'])) {
            return $files->toJson();
        }

        //If limit is based on sum tracks length, use them as DateInterval
        $interval = DateInterval::createFromDateString($limit->value.' '.$limit->modifier);
        $totLengthFromToday = new DateTime();
        $intervalFromToday = clone $totLengthFromToday;
        $intervalFromToday = $intervalFromToday->add($interval);
        $list = collect();
        foreach ($files as $file) {
            $fileLength = new LengthFormatter($file->length);
            $totLengthFromToday->add(DateInterval::createFromDateString($fileLength->toSeconds().' seconds'));
            if ($totLengthFromToday < $intervalFromToday) {
                $list->push($file);
            } else {
                if ($overflow) {
                    $list->push($file);
                    break;
                }
                break;
            }
        }
        return $list->toJson();
        //ToDo: add limit from instance length
    }

    /**
     * Save preview Smart Block Content
     * ToDo: understand when we need to use it
     * @param File $file
     * @param int $block_id
     * @param int $position
     * @return void
     */
    private function saveContent(File $file, int $block_id, int $position = 0) {
        SmartBlockContent::create([
            'block_id' => $block_id,
            'file_id' => $file->id,
            'position' => $position,
            'trackoffset' => 0, //ToDo: understand this field
            'cliplength' => $file->length,
            'cuein' => $file->cuein,
            'cueout' => $file->cueout,
            'fadein' => '00:00:00', //ToDo: add fadein/fadeout
            'fadeout' => '00:00:00',
        ]);
    }
}