<?php

namespace App\Services;

use App\Models\Entry;
use App\Models\ScoreSheet;
use App\Models\ScoringGuide;
use Illuminate\Support\Collection;
use Illuminate\Support\Facades\Cache;
use Illuminate\Support\Facades\DB;
use function array_unshift;

class ScoreService
{
    protected $auditionCache;
    protected $entryCache;
    /**
     * Create a new class instance.
     */
    public function __construct(AuditionCacheService $auditionCache, EntryCacheService $entryCache)
    {
        $this->auditionCache = $auditionCache;
        $this->entryCache = $entryCache;
    }

    /**
     * Cache all scoring guides
     * @return \Illuminate\Database\Eloquent\Collection
     */
    public function getScoringGuides(): \Illuminate\Database\Eloquent\Collection
    {
        $cacheKey = 'scoringGuides';
        return Cache::remember($cacheKey, 3600, fn() => ScoringGuide::with('subscores')->withCount('subscores')->get());
    }

    /**
     * Retrieve a single scoring guide from the cache
     * @param $id
     * @return ScoringGuide
     */
    public function getScoringGuide($id): ScoringGuide
    {
            return $this->getScoringGuides()->find($id);
    }

    /**
     * Clear the scoring guide cache
     * @return void
     */
    public function clearScoringGuideCache(): void
    {
        Cache::forget('scoringGuides');
    }


    /**
     * Returns an array where each key is an entry id and the value is the number
     * of score sheets assigned to that entry.
     * @return Collection
     */
    public function entryScoreSheetCounts()
    {
        $cacheKey = 'entryScoreSheetCounts';
        return Cache::remember($cacheKey, 10, function() {
            // For each Entry get the number of ScoreSheets associated with it
            $entryScoreSheetCounts = ScoreSheet::select('entry_id', DB::raw('count(*) as count'))
                ->groupBy('entry_id')
                ->get()
                ->pluck('count','entry_id');
            return $entryScoreSheetCounts;

        });


    }


    /**
     * Get final scores array for the requested entry. The first element is the total score. The following elements are sums
     * of each subscore in tiebreaker order
     * @param  Entry  $entry
     * @return array
     */
    public function entryTotalScores(Entry $entry)
    {
        $cacheKey = 'entry' . $entry->id . 'totalScores';
        return Cache::remember($cacheKey, 3600, function () use ($entry) {
            return $this->calculateFinalScoreArray($entry->audition->scoring_guide_id, $entry->scoreSheets);
        });
    }

    /**
     * Calculate and cache scores for all entries for the provided audition ID
     * @param $auditionId
     * @return void
     */
    public function calculateScoresForAudition($auditionId)
    {
        $audition = $this->auditionCache->getAudition($auditionId);
        $scoringGuideId = $audition->scoring_guide_id;
//        $entries = Entry::where('audition_id',$auditionId)->with('scoreSheets')->get();
        $entries = $this->entryCache->getEntriesForAudition($auditionId);
        $entries->load('scoreSheets');

        foreach ($entries as $entry) {
            $cacheKey = 'entry' . $entry->id . 'totalScores';
            if (Cache::has($cacheKey)) continue;
            $thisTotalScore = $this->calculateFinalScoreArray($scoringGuideId, $entry->scoreSheets);
            Cache::put($cacheKey,$thisTotalScore,3600);
        }
    }

    /**
     * Calculate final score using the provided scoring guide and score sheets. Returns an array of scores
     * The first element is the total score. The following elements are the sum of each subscore
     * in tiebreaker order.
     * @param $scoringGuideId
     * @param  array|Collection  $scoreSheets
     * @return array
     */
    public function calculateFinalScoreArray($scoringGuideId, array|Collection $scoreSheets): array
    {

        $sg = $this->getScoringGuide($scoringGuideId);

        // TODO cache the scoring guides with their subscores
        $subscores = $sg->subscores->sortBy('tiebreak_order');

        // Init final scores array
        $finalScoresArray = [];
        foreach ($subscores as $subscore) {
            $finalScoresArray[$subscore->id] = 0;
        }

        foreach($scoreSheets as $sheet) {
            foreach ($sheet->subscores as $ss) {
                $finalScoresArray[$ss['subscore_id']] += $ss['score'];
            }
        }

        // calculate weighted final score
        $totalScore = 0;
        $totalWeight = 0;
        foreach ($subscores as $subscore) {
            $totalScore += ($finalScoresArray[$subscore->id] * $subscore->weight);
            $totalWeight += $subscore->weight;
        }
        $totalScore = ($totalScore / $totalWeight);
        array_unshift($finalScoresArray,$totalScore);
        return $finalScoresArray;
    }

    /**
     * Validate that the judge on the score sheet is actually assigned to judge
     * then entry
     * @param  ScoreSheet  $sheet
     * @return bool
     */
    public function validateScoreSheet(ScoreSheet $sheet)
    {
        // TODO use this when calculating scores
        $entry = $this->entryCache->getAllEntries()->find($sheet->entry_id);
        $audition = $this->auditionCache->getAudition($entry->audition_id);
        $validJudges = $audition->judges;
        // send a laravel flash message with an error if the $sheet->user_id is not in the collection $validJudges
        if (!$validJudges->contains('id', $sheet->user_id)) {
            session()->flash('error', 'Entry ID ' . $sheet->entry_id . ' has an invalid score entered by ' . $sheet->judge->full_name());
        }

        // check if $sheet->user_id is in the collection $validJudges, return false if not, true if it is
        return $validJudges->contains('id', $sheet->user_id);


    }

}