<?php
/*
 * 2026-01-08 16:45:00 - Dino Karl
 * GOOGLE HELPER KLASSE V2 (Mit Upload & Album Logic)
 */

class GoogleHelper {
    private $clientId;
    private $clientSecret;
    private $redirectUri;
    private $tokenFile = 'tokens.json';
    private $albumFile = 'album_id.txt'; // Hier merken wir uns die Album ID

    public function __construct($secretJsonPath, $redirectUri) {
        if (!file_exists($secretJsonPath)) die("Fehler: client_secret.json fehlt!");
        $secrets = json_decode(file_get_contents($secretJsonPath), true);
        $conf = isset($secrets['web']) ? $secrets['web'] : (isset($secrets['installed']) ? $secrets['installed'] : null);
        $this->clientId = $conf['client_id'];
        $this->clientSecret = $conf['client_secret'];
        $this->redirectUri = $redirectUri;
    }

    // --- AUTH LOGIK (Unverändert) ---
    public function getAuthUrl() {
        $params = [
            'client_id' => $this->clientId, 'redirect_uri' => $this->redirectUri, 'response_type' => 'code',
            'scope' => 'https://www.googleapis.com/auth/photoslibrary.appendonly',
            'access_type' => 'offline', 'prompt' => 'consent'
        ];
        return 'https://accounts.google.com/o/oauth2/auth?' . http_build_query($params);
    }

    public function authenticate($code) {
        $data = $this->makeRequest('https://oauth2.googleapis.com/token', [
            'code' => $code, 'client_id' => $this->clientId, 'client_secret' => $this->clientSecret,
            'redirect_uri' => $this->redirectUri, 'grant_type' => 'authorization_code'
        ]);
        if (isset($data['access_token'])) { $this->saveTokens($data); return true; }
        return false;
    }

    private function getAccessToken() {
        $tokens = $this->loadTokens();
        if (!$tokens) return null;
        if (time() >= ($tokens['created'] + $tokens['expires_in'] - 60)) {
            return $this->refreshToken($tokens['refresh_token']);
        }
        return $tokens['access_token'];
    }

    private function refreshToken($refresh) {
        $data = $this->makeRequest('https://oauth2.googleapis.com/token', [
            'refresh_token' => $refresh, 'client_id' => $this->clientId,
            'client_secret' => $this->clientSecret, 'grant_type' => 'refresh_token'
        ]);
        if (isset($data['access_token'])) {
            $data['refresh_token'] = $refresh; // Alten Refresh Token behalten
            $this->saveTokens($data);
            return $data['access_token'];
        }
        return null;
    }

    // --- NEU: UPLOAD LOGIK ---

    public function uploadImage($imageData, $description) {
        $token = $this->getAccessToken();
        if (!$token) return ['error' => 'Nicht eingeloggt'];

        // 1. Das Album finden oder erstellen
        $albumId = $this->getOrCreateAlbum($token);

        // 2. Die Bytes hochladen (Schritt 1 von 2 bei Google)
        $uploadUrl = 'https://photoslibrary.googleapis.com/v1/uploads';
        $ch = curl_init($uploadUrl);
        curl_setopt($ch, CURLOPT_HTTPHEADER, [
            "Authorization: Bearer $token",
            "Content-type: application/octet-stream",
            "X-Goog-Upload-Protocol: raw"
        ]);
        curl_setopt($ch, CURLOPT_POST, true);
        curl_setopt($ch, CURLOPT_POSTFIELDS, $imageData);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
        $uploadToken = curl_exec($ch);
        curl_close($ch);

        if (!$uploadToken) return ['error' => 'Upload der Bilddaten fehlgeschlagen'];

        // 3. Das MediaItem erstellen (Schritt 2 von 2)
        $createUrl = 'https://photoslibrary.googleapis.com/v1/mediaItems:batchCreate';
        $body = [
            "albumId" => $albumId,
            "newMediaItems" => [[
                "description" => $description,
                "simpleMediaItem" => ["uploadToken" => $uploadToken]
            ]]
        ];

        $ch = curl_init($createUrl);
        curl_setopt($ch, CURLOPT_HTTPHEADER, ["Authorization: Bearer $token", "Content-type: application/json"]);
        curl_setopt($ch, CURLOPT_POST, true);
        curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($body));
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
        $result = json_decode(curl_exec($ch), true);
        curl_close($ch);

        return $result;
    }

    // Hilfsfunktion: Album Management
    private function getOrCreateAlbum($token) {
        // Haben wir die ID schon gespeichert?
        if (file_exists($this->albumFile)) {
            return trim(file_get_contents($this->albumFile));
        }

        // Nein, wir erstellen es neu.
        // (Hinweis: Wir könnten erst suchen, aber Erstellen ist sicherer/einfacher)
        $url = 'https://photoslibrary.googleapis.com/v1/albums';
        $body = json_encode(["album" => ["title" => "Dino Wissenskarten"]]);
        
        $ch = curl_init($url);
        curl_setopt($ch, CURLOPT_HTTPHEADER, ["Authorization: Bearer $token", "Content-type: application/json"]);
        curl_setopt($ch, CURLOPT_POST, true);
        curl_setopt($ch, CURLOPT_POSTFIELDS, $body);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
        $response = json_decode(curl_exec($ch), true);
        curl_close($ch);

        if (isset($response['id'])) {
            file_put_contents($this->albumFile, $response['id']);
            return $response['id'];
        }
        return null;
    }

    // --- UTIL ---
    private function makeRequest($url, $fields) {
        $ch = curl_init($url);
        curl_setopt($ch, CURLOPT_POST, true);
        curl_setopt($ch, CURLOPT_POSTFIELDS, http_build_query($fields));
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
        $res = curl_exec($ch); curl_close($ch);
        return json_decode($res, true);
    }
    private function saveTokens($data) { $data['created'] = time(); file_put_contents($this->tokenFile, json_encode($data)); }
    private function loadTokens() { return file_exists($this->tokenFile) ? json_decode(file_get_contents($this->tokenFile), true) : null; }
    public function isAuthenticated() { return file_exists($this->tokenFile); }
}
?>