<?php

namespace App\Services\Location;

use Illuminate\Support\Arr;
use Illuminate\Support\Facades\Http;
use Illuminate\Support\Facades\Log;

class Geocoder
{
    public function __construct(
        private array $cfg = []
    ) {
        $this->cfg = config('services.geocoding');
    }

    /**
     * Forward geocode a free-form string.
     * Returns a normalized array for your `locations` table or null.
     */
    public function forward(string $query): ?array
    {
        $provider = $this->cfg['provider'] ?? 'arcgis';

        // Treat obvious non-address labels as non-geocodable (e.g., "Home", "Office")
        if (mb_strlen(trim($query)) < 4) {
            return null;
        }

        return match ($provider) {
            'arcgis' => $this->forwardArcgis($query),
            default  => null,
        };
    }

    /**
     * Reverse geocode lon/lat → address. (Optional)
     */
    public function reverse(float $lat, float $lon): ?array
    {
        $provider = $this->cfg['provider'] ?? 'arcgis';
        return match ($provider) {
            'arcgis' => $this->reverseArcgis($lat, $lon),
            default  => null,
        };
    }

    /* ---------------- ArcGIS World Geocoding ---------------- */

    private function http()
    {
        return Http::retry(3, 500)
            ->timeout((int) ($this->cfg['timeout'] ?? 20))
            ->withHeaders([
                'User-Agent' => $this->cfg['user_agent'] ?? 'Kithkin/Geocoder',
            ]);
    }

    private function arcgisBase(): string
    {
        return rtrim($this->cfg['arcgis']['endpoint'], '/');
    }

    private function forwardArcgis(string $query): ?array
    {
        $params = [
            'singleLine'  => $query,
            'outFields'   => $this->cfg['arcgis']['out_fields'] ?? '*',
            'maxLocations'=> $this->cfg['arcgis']['max_results'] ?? 1,
            'f'           => 'pjson',
            'token'       => $this->cfg['arcgis']['api_key'],
        ];

        // If your plan permits/requests it:
        if (!empty($this->cfg['arcgis']['store'])) {
            $params['forStorage'] = 'true';
        }

        $res = $this->http()->get($this->arcgisBase().'/findAddressCandidates', $params);

        if (!$res->ok()) {
            Log::warning('ArcGIS forward geocode failed', ['status' => $res->status(), 'q' => $query]);
            return null;
        }

        $json = $res->json();
        $cand = Arr::first($json['candidates'] ?? []);
        if (!$cand) {
            return null;
        }

        return $this->normalizeArcgisCandidate($cand, $query);
    }

    private function reverseArcgis(float $lat, float $lon): ?array
    {
        $params = [
            // ArcGIS expects x=lon, y=lat
            'location' => "{$lon},{$lat}",
            'f'        => 'pjson',
            'token'    => $this->cfg['arcgis']['api_key'],
        ];

        if (!empty($this->cfg['arcgis']['store'])) {
            $params['forStorage'] = 'true';
        }

        $res = $this->http()->get($this->arcgisBase().'/reverseGeocode', $params);

        if (!$res->ok()) {
            Log::warning('ArcGIS reverse geocode failed', ['status' => $res->status()]);
            return null;
        }

        $j = $res->json();
        $addr = $j['address'] ?? null;
        if (!$addr) {
            return null;
        }

        return [
            'display_name' => $addr['LongLabel'] ?? $addr['Match_addr'] ?? null,
            'raw_address'  => $addr['Match_addr'] ?? null,
            'street'       => $addr['Address']     ?? null,
            'city'         => $addr['City']        ?? null,
            'state'        => $addr['Region']      ?? null,
            'postal'       => $addr['Postal']      ?? null,
            'country'      => $addr['CountryCode'] ?? null,
            // reverseGeocode returns location as x/y too:
            'lat'          => Arr::get($j, 'location.y'),
            'lon'          => Arr::get($j, 'location.x'),
        ];
    }

    private function normalizeArcgisCandidate(array $c, string $query): array
    {
        $loc   = $c['location']   ?? [];
        $attr  = $c['attributes'] ?? [];

        // Prefer LongLabel → address → Place_addr
        $display = $attr['LongLabel']
            ?? $c['address']
            ?? $attr['Place_addr']
            ?? $query;

        // ArcGIS often returns both 'Address' and 'Place_addr'; use either.
        $street = $attr['Address']    ?? $attr['Place_addr'] ?? null;

        return [
            'display_name' => $display,
            'raw_address'  => $query,
            'street'       => $street,
            'city'         => $attr['City']        ?? null,
            'state'        => $attr['Region']      ?? null,
            'postal'       => $attr['Postal']      ?? null,
            'country'      => $attr['CountryCode'] ?? null,
            // location.x = lon, location.y = lat
            'lat'          => $loc['y'] ?? null,
            'lon'          => $loc['x'] ?? null,
        ];
    }
}