<?php

namespace App\Http\Controllers;

use App\Http\Requests\RainfallRequest;
use App\Http\Resources\RainfallCollection;
use App\Http\Resources\RainfallResource;
use App\Models\Rainfall;
use Carbon\Carbon;
use Carbon\CarbonPeriod;
use Illuminate\Http\Request;
use Illuminate\Support\Collection;

class RainfallController extends Controller
{
    /**
     * Display a listing of the rainfalls.
     */
    public function index(Request $request)
    {
        $rainfalls = $request->user()
            ->rainfalls()
            ->orderByDesc('date')
            ->paginate(15);

        return new RainfallCollection($rainfalls);
    }

    /**
     * Store a newly created resource in storage.
     */
    public function store(RainfallRequest $request)
    {
        $rainfall = $request->user()->rainfalls()->create($request->validated());

        return response()->json(new RainfallResource($rainfall), 201);
    }

    /**
     * Display the specified resource.
     */
    public function show(Request $request, Rainfall $rainfall)
    {
        $rainfall = $request->user()->rainfalls()
            ->where('id', $rainfall->id)
            ->first();

        return response()->json(new RainfallResource($rainfall));
    }

    /**
     * Update the specified resource in storage.
     */
    public function update(RainfallRequest $request, Rainfall $rainfall)
    {
        $rainfall = $request->user()->rainfalls()
            ->where('id', $rainfall->id)
            ->first()?->update($request->validated());

        return response()->json(new RainfallResource($rainfall));
    }

    /**
     * Remove the specified resource from storage.
     */
    public function destroy(Request $request, Rainfall $rainfall)
    {
        $request->user()->rainfalls()
            ->where('id', $rainfall->id)
            ->first()?->delete();

        return response()->noContent();
    }

    public function lastRainfalls(Request $request)
    {
        $rainfalls = $request->user()
            ->rainfalls()
            ->orderByDesc('date')
            ->limit(5)
            ->get();

        return response()->json(RainfallResource::collection($rainfalls));
    }

    public function graphValue(Request $request)
    {
        $data = $request->validate([
            'start' => 'date',
            'end' => 'date',
        ]);

        $rainfalls = $request->user()
            ->rainfalls()
            ->whereBetween('date', [$data['start'], $data['end']])
            ->orderBy('date')
            ->get()
            ->groupBy('date');

        $results = collect();
        $index = 0;
        foreach ($rainfalls as $date => $rainfall) {
            if ($index === 0 && $date !== $data['start']) {
                [$results, $index] = $this->addEmptyDays($results, $index, $data['start'], (new Carbon($date))->subDay());
            } elseif ($index > 0 && (new Carbon($results->last()['date']))->addDay()->format('Y-m-d') !== $date) {
                [$results, $index] = $this->addEmptyDays($results, $index, (new Carbon($results->last()['date']))->addDay(), (new Carbon($date))->subDay());
            }

            $results->push([
                'id' => $index++,
                'date' => $date,
                'value' => $rainfall->sum('value'),
            ]);
        }

        if ($results->isNotEmpty() && $results->last()['date'] !== $data['end']) {
            [$results] = $this->addEmptyDays($results, $index, (new Carbon($results->last()['date']))->addDay(), $data['end']);
        }

        return response()->json($results);
    }

    private function addEmptyDays(Collection $results, int $index, Carbon|string $start, Carbon|string $end)
    {
        foreach (CarbonPeriod::create($start, $end) as $date) {
            $results->push([
                'id' => $index++,
                'date' => $date->format('Y-m-d'),
                'value' => 0,
            ]);
        }

        return [$results, $index];
    }
}