<?php

namespace classes;

require_once WD . '/modules/bird/bird_c.php';

use bird\bird_c;
use Exception;

class bird
{
    /**
     * Configuration of the Bird module
     * @var bird_c|object
     */
    public $config;

    public function __construct()
    {
        $this->config = new bird_c();
    }

    /**
     * Ensure module is enabled
     * @throws Exception
     */
    function requireModuleEnabled(): void
    {
        if (!$this->config->enabled->isTrue()) {
            throw new Exception('The bird module is not enabled');
        }
    }

    /**
     * Ensure API key is present
     * @throws Exception
     */
    function requireValidApiKey(): void
    {
        $k = $this->config->api_key->getVariableValue();
        if ($k === null || $k === '') {
            throw new Exception('Invalid API key defined in the config (bird_api_key_c)');
        }
    }

    /**
     * Ensure base URL is defined
     * @throws Exception
     */
    function requireValidServerURL(): void
    {
        $u = $this->config->server_url->getVariableValue();
        if ($u === null || $u === '') {
            throw new Exception('Invalid server URL defined in the config (bird_server_url_c)');
        }
    }

    /**
     * Send a request to Bird API
     * @param string $endpoint e.g. "/v1/devices"
     * @param array $data request body
     * @param string $method HTTP method (currently only POST supported)
     * @return object|array|null
     * @throws Exception
     */
    function sendRequest(string $endpoint, array $data = [], string $method = 'POST'): object|array|null
    {
        $this->requireModuleEnabled();
        $this->requireValidApiKey();
        $this->requireValidServerURL();
        return match (strtoupper($method)) {
            'POST' => $this->sendPostRequest($endpoint, $data),
            'GET'  => $this->sendGetRequest($endpoint, $data),
            default => throw new Exception('Invalid request method'),
        };
    }

    /**
     * Send POST request
     * @param string $endpoint
     * @param array $data
     * @return array|object|null
     * @throws Exception
     */
    function sendPostRequest(string $endpoint, array $data): array|object|null
    {
        $this->requireModuleEnabled();
        $this->requireValidApiKey();
        $this->requireValidServerURL();

        $url = rtrim($this->config->server_url->getVariableValue(), '/') . $endpoint;
        $headers = [
            'Content-Type: application/json',
            'Authorization: Bearer ' . $this->config->api_key->getVariableValue(),
        ];
        $body = json_encode($data);

        $result = $this->doHttpRequest('POST', $url, $headers, $body);
        $status = (int)($result['status_code'] ?? 0);
        $response = $result['body'] ?? '';
        if ($status >= 400) {
            throw new Exception('Bird API request failed with status ' . $status);
        }
        if ($response === '' || $response === false || $response === null) {
            return null;
        }
        $decoded = json_decode($response);
        return $decoded ?? $response;
    }

    /**
     * Low-level HTTP transport (curl). Tests can override this to stub network.
     * @param string $method
     * @param string $url
     * @param array $headers
     * @param string $body
     * @return array{status_code:int, body:string|false}
     * @throws Exception
     */
    protected function doHttpRequest(string $method, string $url, array $headers, string $body = ''): array
    {
        $ch = curl_init();
        curl_setopt($ch, CURLOPT_URL, $url);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
        $upper = strtoupper($method);
        if ($upper === 'POST') {
            curl_setopt($ch, CURLOPT_POST, true);
            curl_setopt($ch, CURLOPT_POSTFIELDS, $body);
        } else {
            curl_setopt($ch, CURLOPT_CUSTOMREQUEST, $upper);
        }
        curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
        $resp = curl_exec($ch);
        $code = curl_getinfo($ch, CURLINFO_HTTP_CODE);
        if (curl_errno($ch)) {
            $err = curl_error($ch);
            curl_close($ch);
            throw new Exception('cURL error: ' . $err);
        }
        curl_close($ch);
        return [
            'status_code' => (int)$code,
            'body' => $resp,
        ];
    }

    /**
     * Send GET request
     * @param string $endpoint
     * @param array $query
     * @return array|object|null
     * @throws Exception
     */
    function sendGetRequest(string $endpoint, array $query = []): array|object|null
    {
        $this->requireModuleEnabled();
        $this->requireValidApiKey();
        $this->requireValidServerURL();

        $base = rtrim($this->config->server_url->getVariableValue(), '/');
        $url = $base . $endpoint;
        if (!empty($query)) {
            $qs = http_build_query($query);
            $url .= (str_contains($url, '?') ? '&' : '?') . $qs;
        }
        $headers = [
            'Content-Type: application/json',
            'Authorization: Bearer ' . $this->config->api_key->getVariableValue(),
        ];
        $result = $this->doHttpRequest('GET', $url, $headers);
        $status = (int)($result['status_code'] ?? 0);
        $response = $result['body'] ?? '';
        if ($status >= 400) {
            throw new Exception('Bird API request failed with status ' . $status);
        }
        if ($response === '' || $response === false || $response === null) {
            return null;
        }
        $decoded = json_decode($response);
        return $decoded ?? $response;
    }
}