package com.evsuite.abrp;

import android.content.Context;
import android.content.SharedPreferences;

/**
 * The ABRP credentials for sending live data straight from the car: the API key (which app is
 * sending) and the user token (which car in which ABRP account). Kept in {@link SecurePrefs}
 * next to the server settings, entered on the Live data tab or imported from a config file.
 *
 * The car is the only one that sends to ABRP: the server stores live data but does not forward
 * it. Without these, ABRP gets no live data.
 */
final class AbrpConfig {

    static final String KEY_API_KEY = "abrp_api_key";
    static final String KEY_USER_TOKEN = "abrp_user_token";

    final String apiKey;
    final String userToken;

    private static volatile AbrpConfig current;

    AbrpConfig(String apiKey, String userToken) {
        this.apiKey = apiKey;
        this.userToken = userToken;
    }

    boolean isConfigured() {
        return !apiKey.isEmpty() && !userToken.isEmpty();
    }

    static AbrpConfig get(Context context) {
        AbrpConfig config = current;
        if (config != null) return config;
        synchronized (AbrpConfig.class) {
            if (current == null) {
                SharedPreferences prefs = SecurePrefs.get(context);
                current = new AbrpConfig(prefs.getString(KEY_API_KEY, ""), prefs.getString(KEY_USER_TOKEN, ""));
            }
            return current;
        }
    }

    /** Stores trimmed values; empty strings switch direct sending off. */
    static synchronized void save(Context context, String apiKey, String userToken) {
        String key = apiKey == null ? "" : apiKey.trim();
        String token = userToken == null ? "" : userToken.trim();
        SecurePrefs.get(context).edit()
                .putString(KEY_API_KEY, key)
                .putString(KEY_USER_TOKEN, token)
                .apply();
        current = new AbrpConfig(key, token);
    }

    /** Plausible as an ABRP credential: no spaces, not absurdly short or long. */
    static boolean isPlausible(String value) {
        if (value == null) return false;
        String v = value.trim();
        return v.length() >= 8 && v.length() <= 200 && !v.contains(" ");
    }
}