<?php

namespace App\Http\Controllers;

use App\Models\Aircraft;
use App\Models\Airline;
use App\Models\Airport;
use App\Models\ImportedFlight;
use Carbon\Carbon;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\Auth;

class FlightImportController extends Controller
{

    const array FLIGHT_CLASSES = [
        0 => 'Please Select',
        1 => 'Economy',
        2 => 'Business',
        3 => 'First',
        4 => 'Premium Economy',
        5 => 'Private',
    ];

    const array SEAT_TYPES = [
        0 => 'Please Select',
        1 => 'Window',
        2 => 'Middle',
        3 => 'Aisle',
    ];

    const array FLIGHT_REASONS = [
        0 => 'Please Select',
        1 => 'Pleasure',
        2 => 'Business',
        3 => 'Crew',
        4 => 'Other',
    ];

    private function formatTime(?string $time): string
    {
        if (!$time) return '00:00';

        [$hours, $minutes] = explode(':', $time);
        return str_pad($hours, 2, '0', STR_PAD_LEFT) . ':' . $minutes;
    }

    public function getPossibleAircraft(string $aircraftQuery) {
        preg_match('/\((\w+)\)/', $aircraftQuery, $matches);
        $designator = $matches[1] ?? null;

        if(!$designator){
            $aircraft = [];
        } else {

            $aircraft = Aircraft::when($designator, fn($query) => $query->where('designator', 'ilike', $designator))
                ->orderBy('model_full_name')
                ->limit(10)
                ->get(['id', 'manufacturer_code', 'model_full_name', 'designator'])
                ->map(fn($a) => [
                    'value' => $a->id,
                    'title' => "{$a->manufacturer_code} {$a->model_full_name} ({$a->designator})",
                ])
                ->values()
                ->toArray();
        }

        return $aircraft;
    }

    public function getPossibleAirports(string $airportQuery) {
        preg_match('/\((\w{3})\/(\w{4})\)/', $airportQuery, $matches);
        $iata = $matches[1] ?? null;
        $icao = $matches[2] ?? null;

        if (!$iata && !$icao) {
            return [];
        }

        $airports = Airport::with('region.country')
            ->where(function ($q) use ($iata, $icao) {
            $q->where('iata_code', 'ilike', $iata)
                ->orWhere('icao_code', 'ilike', $icao);
        })
            ->orderByRaw("
            CASE
                WHEN iata_code = ? AND icao_code = ? THEN 0
                WHEN iata_code = ? THEN 1
                WHEN icao_code = ? THEN 2
                ELSE 3
            END
        ", [$iata, $icao, $iata, $icao])
            ->limit(10)
            ->get(['id', 'name', 'municipality', 'iata_code', 'icao_code', 'region_id'])
            ->map(fn($a) => [
                'value' => $a->id,
                'title' => "{$a->name} ({$a->iata_code}/{$a->icao_code})",
                'country_code' => strtolower($a?->region->country->code ?? ''),
            ])
            ->values()
            ->toArray();

        return $airports;
    }

    public function getPossibleAirlines(string $airlineQuery) {
        preg_match('/\((\w{2,3})\/(\w{3,4})\)/', $airlineQuery, $matches);
        $iata = $matches[1] ?? null;
        $icao = $matches[2] ?? null;

        $airlines = Airline::when($iata || $icao, function ($query) use ($iata, $icao) {
            $query->orderByRaw("
            CASE
                WHEN \"IATA_code\" = ? AND \"ICAO_code\" = ? THEN 0
                WHEN \"IATA_code\" = ? THEN 1
                WHEN \"ICAO_code\" = ? THEN 2
                ELSE 3
            END
        ", [$iata, $icao, $iata, $icao])
                ->where(function ($q) use ($iata, $icao) {
                    $q->where('IATA_code', $iata)
                        ->orWhere('ICAO_code', $icao);
                });
        })
            ->orderByDesc('active')
            ->limit(10)
            ->get(['id', 'name', 'IATA_code', 'ICAO_code'])
            ->map(fn($a) => [
                'value' => $a->id,
                'title' => "{$a->name} ({$a->IATA_code}/{$a->ICAO_code})",
            ])
            ->values()
            ->toArray();


            return $airlines;
    }

    public function reconcile(Request $request)
    {
        $user = Auth::user();

        $flightToReconcile = ImportedFlight::where('user_id', $user->id)->orderBy('id')->first();

        if (!$flightToReconcile) {
            return null;
        }

        $date = null;
        if ($flightToReconcile->date) {
            $date = Carbon::createFromFormat('m-d-y', $flightToReconcile->date)->format('Y-m-d');
        }


        return [
            'flight_classes' => collect(self::FLIGHT_CLASSES)->map(fn($title, $value) => [
                'value' => $value,
                'title' => $title,
            ])->values(),
            'flight_reasons' => collect(self::FLIGHT_REASONS)->map(fn($title, $value) => [
                'value' => $value,
                'title' => $title,
            ])->values(),
            'seat_types' => collect(self::SEAT_TYPES)->map(fn($title, $value) => [
                'value' => $value,
                'title' => $title,
            ])->values(),

            'flight_number' => $flightToReconcile->flight_number ?? '',
            'date'          => $date ?? '',
            'dep_time'      => $this->formatTime($flightToReconcile->dep_time),
            'arr_time'      => $this->formatTime($flightToReconcile->arr_time),
            'duration'      => $this->formatTime($flightToReconcile->duration),
            'registration'  => $flightToReconcile->registration ?? '',
            'note'          => $flightToReconcile->note ?? '',
            'seat_number'   => $flightToReconcile->seat_number ?? '',
            'flight_class'  => $flightToReconcile->flight_class ?? '',
            'seat_type'     => $flightToReconcile->seat_type ?? '',
            'flight_reason' => $flightToReconcile->flight_reason ?? '',
            'airline_options' => $this->getPossibleAirlines($flightToReconcile->airline ?? ''),
            'to_options' => $this->getPossibleAirports($flightToReconcile->to ?? ''),
            'from_options' => $this->getPossibleAirports($flightToReconcile->from ?? ''),
            'aircraft_options' => $this->getPossibleAircraft($flightToReconcile->aircraft ?? ''),
        ];
    }

    public function save(Request $request){
        $validated = $request->validate([
            'date' => 'required|date',
            'flight_number' => 'required|string',
            'from_id' => 'required|integer|exists:airports,id',
            'to_id' => 'required|integer|exists:airports,id',
            'dep_time' => 'nullable|date_format:H:i',
            'arr_time' => 'nullable|date_format:H:i',
            'duration' => 'nullable|date_format:H:i',
            'airline_id' => 'nullable|integer|exists:airlines,id',
            'aircraft_id' => 'nullable|integer|exists:aircraft,id',
            'registration' => 'nullable|string',
            'seat_number' => 'nullable|string',
            'seat_type_id' => 'nullable|integer',
            'flight_class_id' => 'nullable|integer',
            'flight_reason_id' => 'nullable|integer',
            'note' => 'nullable|string',
        ],[
            'from_id.required' => 'Please select a departure airport.',
            'to_id.required' => 'Please select an arrival airport.',
            'dep_time.date_format' => 'Departure time must be in HH:MM format, i.e: 01:25',
            'arr_time.date_format' => 'Arrival time must be in HH:MM format, i.e: 12:25',
            'duration.date_format' => 'Must be in HH:MM format, e.g: 03:37',
        ]);

    }

    public function store(Request $request)
    {
        try {
            $request->validate([
                'csv' => ['required', 'file', 'mimes:csv,txt', 'max:10240'],
            ]);

            $path = $request->file('csv')->getRealPath();
            $handle = fopen($path, 'r');

            fgetcsv($handle);

            // Read and normalise header row
            $headers = array_map(
                fn($h) => strtolower(trim(str_replace(' ', '_', $h))),
                fgetcsv($handle)
            );

            \Log::debug('CSV headers', $headers);
            $firstRow = fgetcsv($handle);
            \Log::debug('First row', $firstRow ?? ['empty']);
            \Log::debug('Header count: ' . count($headers) . ', Row count: ' . count($firstRow ?? []));

            $map = [
                'date'          => 'date',
                'flight_number' => 'flight_number',
                'from'          => 'from',
                'to'            => 'to',
                'dep_time'      => 'dep_time',
                'arr_time'      => 'arr_time',
                'duration'      => 'duration',
                'airline'       => 'airline',
                'aircraft'      => 'aircraft',
                'registration'  => 'registration',
                'seat_number'   => 'seat_number',
                'seat_type'     => 'seat_type',
                'flight_class'  => 'flight_class',
                'flight_reason' => 'flight_reason',
                'note'          => 'note',
            ];

            $userId = Auth::id();
            $imported = 0;

            while (($row = fgetcsv($handle)) !== false) {
                if (count($row) !== count($headers)) {
                    continue; // skip malformed rows
                }

                $raw = array_combine($headers, $row);
                $data = ['user_id' => $userId];

                foreach ($map as $csvKey => $column) {
                    $data[$column] = $raw[$csvKey] ?? null;
                }

                ImportedFlight::create($data);
                $imported++;
            }

            fclose($handle);

            return response()->json(['imported' => $imported]);
        } catch (\Exception $e) {
            return response()->json(['message' => $e->getMessage()], 500);
        }
    }
}