<?php

namespace App\Http\Controllers;

use App\Http\Requests\StatsByBrandRequest;
use App\Http\Requests\StatsByQuestionRequest;
use App\Models\Brand;
use App\Models\BrandStat;
use App\Models\CustomerAnswer;
use App\Models\Question;
use Illuminate\Support\Carbon;
use Illuminate\Support\Collection;
use Illuminate\Support\Facades\Schema;
use League\Csv\Writer;

/**
 * @codeCoverageIgnore
 */
class StatsController extends Controller
{
    /**
     * Shows stats by brand
     *
     * @param StatsByBrandRequest $request
     * @return \Illuminate\Http\Response
     */
    public function viewStatsByBrand(StatsByBrandRequest $request)
    {
        $stats = null;
        if ($request->post()) {
            $stats = BrandStat::whereDate('created_at', '>=', $request->start)
                ->whereDate('created_at', '<=', $request->end)
                ->whereBrandId($request->brand)->get();
        }
        return view('stats.view-stats-by-brands', \compact('stats'));
    }

    /**
     * Exports stats by brand as a csv file
     *
     * @param StatsByBrandRequest $request
     * @return \Illuminate\Http\Response
     */
    public function exportByBrandCsv(StatsByBrandRequest $request)
    {
        $brand = Brand::findOrFail($request->brand);
        $stats = BrandStat::with('brand')->whereDate('created_at', '>=', $request->start)
            ->whereDate('created_at', '<=', $request->end)
            ->whereBrandId($request->brand)->get();

        $columns = collect(Schema::getColumnListing((new BrandStat())->getTable()))
            ->filter(function ($value) {
                return !in_array($value, ['created_at', 'brand_id']);
            })->all();

        $header = '"date";"marque";' . implode(';', $columns);

        $w = Writer::createFromString($header . PHP_EOL);
        $w->setDelimiter(';');
        $w->setEnclosure('"');
        $w->setOutputBOM(Writer::BOM_UTF8);

        foreach ($stats as $stat) {
            $cols = [
                $stat->created_at->format('Y-m-d'),
                $stat->brand->name
            ];
            foreach ($columns as $colname) {
                $cols[] = $stat->{$colname};
            }
            $w->insertOne($cols);
        }
        return response((string)$w, 200, [
            'Content-Encoding' => 'none',
            'Content-Type' => 'text/csv; charset=UTF-8',
            // phpcs:ignore Generic.Files.LineLength.TooLong
            'Content-Disposition' => "attachment; filename=\"Statistiques du $request->start au $request->end pour $brand->name.csv\"",
            'Content-Description' => 'File Transfer',
        ]);
    }

    /**
     * Views stats for a specific question
     *
     * @param StatsByQuestionRequest $request
     * @return \Illuminate\Http\Response
     */
    public function viewByQuestion(StatsByQuestionRequest $request)
    {
        $question      = null;
        $answers       = null;
        $answersByDays = null;
        if ($request->post()) {
            $question = Question::findOrFail($request->question);
            $answers  = $question->answers;
            $start    = Carbon::parse($request->start);
            $end      = Carbon::parse($request->end);

            $answersByDays = $this->answersByDays($answers, $start, $end);
        }

        return view('stats.view-stats-by-questions', \compact('question', 'answers', 'answersByDays'));
    }

    /**
     * Exports stats for a specific question as csv
     *
     * @param StatsByQuestionRequest $request
     * @return \Illuminate\Http\Response
     */
    public function exportByQuestionCsv(StatsByQuestionRequest $request)
    {
        $question = Question::findOrFail($request->question);
        $answers  = $question->answers;
        $start    = Carbon::parse($request->start);
        $end      = Carbon::parse($request->end);

        $answersByDays = $this->answersByDays($answers, $start, $end);

        $header = '"date";' . implode(';', $answers->map(function ($answer) {
            return "\"$answer->answer\"";
        })->all());

        $w = Writer::createFromString($header . PHP_EOL);
        $w->setDelimiter(';');
        $w->setEnclosure('"');
        $w->setOutputBOM(Writer::BOM_UTF8);

        foreach ($answersByDays as $day => $dayAnswers) {
            $w->insertOne(array_merge(
                [
                    $day
                ],
                $dayAnswers->values()->all()
            ));
        }
        return response((string)$w, 200, [
            'Content-Encoding' => 'none',
            'Content-Type' => 'text/csv; charset=UTF-8',
            // phpcs:ignore Generic.Files.LineLength.TooLong
            'Content-Disposition' => "attachment; filename=\"Statistiques du $request->start au $request->end pour $question->question.csv\"",
            'Content-Description' => 'File Transfer',
        ]);
    }

    /**
     * Makes a collection of total users answers by day
     *
     * @param Collection $answers A collection of Answer.
     * @param Carbon     $start   The wanted start period.
     * @param Carbon     $end     The wanted end period.
     * @return Collection A collection with date as Y_m_d index with array of answers and their total.
     */
    private function answersByDays(Collection $answers, Carbon $start, Carbon $end): Collection
    {
        // * Totalize by date all answers.
        $answersByDays = CustomerAnswer::whereDate('created_at', '>=', $start)
            ->whereDate('created_at', '<=', $end)
            ->whereIn('answer_id', $answers->pluck('id'))
            ->get()->map(function ($custAnswer) {
                return [
                    'answer_id' => $custAnswer->answer_id,
                    'created_at' => $custAnswer->created_at->format('Y-m-d'),
                ];
            })->groupBy(['created_at', 'answer_id'])->map(function ($day) {
                return $day->map(function ($custAnswers) {
                    return $custAnswers->count();
                });
            });

        do {
            $currentDate = $start->format('Y-m-d');
            /** @var \Illuminate\Support\Collection $answersByDays */
            if (!$answersByDays->has($currentDate)) {
                $answersByDays->put(
                    $currentDate,
                    $answers->mapWithKeys(function ($answer) {
                        return [$answer->answer => 0];
                    })
                );
            } else {
                $curentAnswers = $answersByDays->pull($currentDate);
                $answersByDays->put(
                    $currentDate,
                    $answers->mapWithKeys(function ($answer) use ($curentAnswers) {
                        return [$answer->answer =>
                        $curentAnswers->has($answer->id) ?
                        $curentAnswers->get($answer->id) : 0];
                    })
                );
            }

            $start = $start->addDay();
        } while ($start->lessThanOrEqualTo($end));

        return $answersByDays;
    }
}