<?php

declare(strict_types=1);

namespace Ohrionmartin\Weather\Service;

use GuzzleHttp\ClientInterface;
use GuzzleHttp\Exception\GuzzleException;

final class OpenWeatherClient
{
    private ClientInterface $http;
    private string $apiKey;
    private string $baseUrl;

    public function __construct(
        ClientInterface $http,
        string $apiKey,
        string $baseUrl = 'https://api.openweathermap.org/data/3.0'
    ) {
        $this->http = $http;
        $this->apiKey = $apiKey;
        $this->baseUrl = rtrim($baseUrl, '/');
    }

    /**
     * Fetch One Call (3.0) current/forecast data
     *
     * @param float $lat
     * @param float $lon
     * @param array{
     *   exclude?: string,
     *   units?: 'standard'|'metric'|'imperial',
     *   lang?: string
     * } $options
     * @return array<string,mixed>
     * @throws \RuntimeException on HTTP or API error
     */
    public function oneCall(float $lat, float $lon, array $options = []): array
    {
        $query = [
            'lat'   => $lat,
            'lon'   => $lon,
            'appid' => $this->apiKey,
        ];

        if (!empty($options['exclude'])) {
            $query['exclude'] = $options['exclude']; // comma-separated string
        }
        if (!empty($options['units'])) {
            $query['units'] = $options['units'];
        }
        if (!empty($options['lang'])) {
            $query['lang'] = $options['lang'];
        }

        try {
            $res = $this->http->request('GET', "{$this->baseUrl}/onecall", [
                'query' => $query,
                'http_errors' => false,
                'timeout' => 8.0,
                'connect_timeout' => 5.0,
            ]);
        } catch (GuzzleException $e) {
            throw new \RuntimeException('Weather service is unavailable', 0, $e);
        }

        $status = $res->getStatusCode();
        $body = (string) $res->getBody();

        $data = json_decode($body, true);
        if (json_last_error() !== JSON_ERROR_NONE) {
            throw new \RuntimeException('Invalid response from weather service');
        }

        if ($status >= 400) {
            $message = $data['message'] ?? 'OpenWeather API error';
            throw new \RuntimeException($message);
        }

        return $data;
    }

    /**
     * Geocode a city name to coordinates using OpenWeather Geocoding API.
     *
     * @param string $city
     * @return array{lat: float, lon: float}
     */
    public function geocodeCity(string $city): array
    {
        $query = [
            'q'     => $city,
            'limit' => 1,
            'appid' => $this->apiKey,
        ];

        try {
            $res = $this->http->request('GET', 'https://api.openweathermap.org/geo/1.0/direct', [
                'query' => $query,
                'http_errors' => false,
                'timeout' => 8.0,
                'connect_timeout' => 5.0,
            ]);
        } catch (GuzzleException $e) {
            throw new \RuntimeException('Geocoding service is unavailable', 0, $e);
        }

        $status = $res->getStatusCode();
        $body = (string) $res->getBody();

        $data = json_decode($body, true);
        if (json_last_error() !== JSON_ERROR_NONE) {
            throw new \RuntimeException('Invalid response from geocoding service');
        }

        if ($status >= 400) {
            $message = is_array($data) && isset($data['message']) ? $data['message'] : 'Geocoding API error';
            throw new \RuntimeException($message);
        }

        if (!is_array($data) || count($data) === 0 || !isset($data[0]['lat'], $data[0]['lon'])) {
            throw new \RuntimeException('City not found');
        }

        return [
            'lat' => (float) $data[0]['lat'],
            'lon' => (float) $data[0]['lon'],
        ];
    }

    /**
     * Convenience method: One Call by city name.
     *
     * @param string $city
     * @param array{
     *   exclude?: string,
     *   units?: 'standard'|'metric'|'imperial',
     *   lang?: string
     * } $options
     * @return array<string,mixed>
     */
    public function oneCallByCity(string $city, array $options = []): array
    {
        $coords = $this->geocodeCity($city);
        return $this->oneCall($coords['lat'], $coords['lon'], $options);
    }
}