<?php

namespace App\Http\Controllers\NominationEnsembles;

use App\Http\Controllers\Controller;
use App\Models\NominationEnsemble;
use App\Models\NominationEnsembleEntry;
use App\Models\School;
use App\Models\Student;

class ScobdaNominationEnsembleEntryController extends Controller implements NominationEnsembleEntryController
{
    public function index()
    {
        $ensembles = NominationEnsemble::all();
        // populate an array with each ensemble id as a key. Each item will be a collection of students available to be nominated
        $availableStudents = [];
        // populate an array with each ensemble id as a key. Each item will be a collection of available instruments
        $availableInstruments = [];
        // populate an array with each ensemble id as a key. Each item will be a collection of nominationEntries already made
        $nominatedStudents = [];
        // an array of bool values with each ensemble id as a key. It will be true if additional nominations are available
        $nominationsAvailable = [];
        foreach ($ensembles as $ensemble) {
            // Gather a collection of students who may be nominated for this ensemble
            $availableStudents[$ensemble->id] = Student::where('grade', '<=', $ensemble->maximum_grade)
                ->where('grade', '>=', $ensemble->minimum_grade)
                ->where('school_id', auth()->user()->school_id)
                ->orderBy('last_name')
                ->orderBy('first_name')
                ->get();
            $availableInstruments[$ensemble->id] = $ensemble->data['instruments'];
            $nominatedStudents[$ensemble->id] = $this->collapseNominations(auth()->user()->school, $ensemble,
                'nominations');

            $nominatedStudentIds = [];

            // Removed students already nominated from available students
            foreach ($nominatedStudents[$ensemble->id] as $nominatedStudent) {
                $nominatedStudentIds[] = $nominatedStudent->student_id;
            }
            $availableStudents[$ensemble->id] = $availableStudents[$ensemble->id]->reject(function ($student) use (
                $nominatedStudentIds
            ) {
                return in_array($student->id, $nominatedStudentIds);
            });

            $nominationsAvailable[$ensemble->id] = $ensemble->data['max_nominations'] > count($nominatedStudents[$ensemble->id]);

        }

        return view('nomination_ensembles.scobda.entries.index',
            compact('ensembles', 'availableStudents', 'availableInstruments', 'nominatedStudents',
                'nominationsAvailable'));
    }

    public function show(NominationEnsembleEntry $entry)
    {
        // TODO: Implement show() method.
    }

    public function create()
    {
        // TODO: Implement create() method.
    }

    public function store()
    {
        $validData = request()->validate([
            'ensemble' => [
                'required',
                'exists:App\Models\NominationEnsemble,id',
            ],
            'new_student' => [
                'required',
                'exists:App\Models\Student,id',
            ],
            'new_instrument' => 'required',
        ]);

        if (NominationEnsembleEntry::where('student_id', $validData['new_student'])
            ->where('nomination_ensemble_id', $validData['ensemble'])
            ->count() > 0) {
            return redirect()->route('nomination.entry.index')->with('error',
                'Student already nominated for that ensemble');
        }

        $proposedEnsemble = NominationEnsemble::find($validData['ensemble']);

        if (! in_array($validData['new_instrument'], $proposedEnsemble->data['instruments'])) {
            return redirect()->route('nomination.entry.index')->with('error',
                'Invalid Instrument specified');
        }

        $student = Student::find($validData['new_student']);
        if (auth()->user()->school_id !== $student->school_id) {
            return redirect()->route('nomination.entry.index')->with('error',
                'You may only nominate students from your school');
        }
        $nextRank = $this->collapseNominations($student->school, $proposedEnsemble, 'next');
        if ($nextRank > $proposedEnsemble->data['max_nominations']) {
            return redirect()->route('nomination.entry.index')->with('error',
                'You have already used all of your nominations');
        }

        $entry = new NominationEnsembleEntry();
        $entry->student_id = $validData['new_student'];
        $entry->nomination_ensemble_id = $validData['ensemble'];
        $data = [];
        $data['rank'] = $nextRank;
        $data['instrument'] = $validData['new_instrument'];
        $entry->data = $data;
        $entry->save();

        return redirect()->route('nomination.entry.index')->with('success',
            'Nomination Recorded');
    }

    public function edit(NominationEnsembleEntry $entry)
    {
        // TODO: Implement edit() method.
    }

    public function update(NominationEnsembleEntry $entry)
    {
        // TODO: Implement update() method.
    }

    public function destroy(NominationEnsembleEntry $entry)
    {
        if ($entry->student->school_id !== auth()->user()->school_id) {
            return redirect()->route('nomination.entry.index')->with('error',
                'You may only delete nominations from your school');
        }
        $entry->delete();

        return redirect()->route('nomination.entry.index')->with('success', 'Nomination Deleted');
    }

    /**
     * Given a school and nomination ensemble, consolidate the rank valuek
     *
     * if returnType is next, the next available rank will be returned
     * if returnType is nominations, a collection of nominations will be returned
     *
     * @return int|array
     *
     * @var returnType = next|nominations
     */
    private function collapseNominations(School $school, NominationEnsemble $ensemble, $returnType)
    {
        $nominations = $school->nominations()->get()->where('nomination_ensemble_id',
            $ensemble->id)->sortBy('data.rank');
        $n = 1;
        foreach ($nominations as $nomination) {
            $nomination->update(['data->rank' => $n]);
            $n++;
        }

        if ($returnType == 'next') {
            return $n;
        }

        return $nominations;
    }
}