package com.reactnativezalokit;

import android.content.Context;
import android.content.pm.PackageInfo;
import android.content.pm.PackageManager;
import android.content.pm.Signature;
import android.util.Base64;

import com.facebook.react.bridge.WritableArray;
import com.facebook.react.bridge.WritableMap;
import com.facebook.react.bridge.WritableNativeArray;
import com.facebook.react.bridge.WritableNativeMap;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import java.nio.charset.StandardCharsets;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.util.Iterator;

public class Util {
  public static WritableMap convertJsonToMap(JSONObject jsonObject) throws JSONException {
    WritableMap map = new WritableNativeMap();

    Iterator<String> iterator = jsonObject.keys();
    while (iterator.hasNext()) {
      String key = iterator.next();
      Object value = jsonObject.get(key);
      if (value instanceof JSONObject) {
        map.putMap(key, convertJsonToMap((JSONObject) value));
      } else if (value instanceof JSONArray) {
        map.putArray(key, convertJsonToArray((JSONArray) value));
      } else if (value instanceof Boolean) {
        map.putBoolean(key, (Boolean) value);
      } else if (value instanceof Integer) {
        map.putInt(key, (Integer) value);
      } else if (value instanceof Double) {
        map.putDouble(key, (Double) value);
      } else if (value instanceof String) {
        map.putString(key, (String) value);
      } else {
        map.putString(key, value.toString());
      }
    }
    return map;
  }

  public static WritableArray convertJsonToArray(JSONArray jsonArray) throws JSONException {
    WritableArray array = new WritableNativeArray();

    for (int i = 0; i < jsonArray.length(); i++) {
      Object value = jsonArray.get(i);
      if (value instanceof JSONObject) {
        array.pushMap(convertJsonToMap((JSONObject) value));
      } else if (value instanceof JSONArray) {
        array.pushArray(convertJsonToArray((JSONArray) value));
      } else if (value instanceof Boolean) {
        array.pushBoolean((Boolean) value);
      } else if (value instanceof Integer) {
        array.pushInt((Integer) value);
      } else if (value instanceof Double) {
        array.pushDouble((Double) value);
      } else if (value instanceof String) {
        array.pushString((String) value);
      } else {
        array.pushString(value.toString());
      }
    }
    return array;
  }

  public static String getApplicationHashKey(Context ctx) throws Exception {
    PackageInfo info = ctx.getPackageManager().getPackageInfo(ctx.getPackageName(), PackageManager.GET_SIGNATURES);
    for (Signature signature : info.signatures) {
      MessageDigest md = MessageDigest.getInstance("SHA");
      md.update(signature.toByteArray());
      String sig = Base64.encodeToString(md.digest(), Base64.DEFAULT).trim();
      if (sig.trim().length() > 0) {
        return sig;
      }
    }

    return "";
  }

  public static String generateCodeVerifier() {
    SecureRandom sr = new SecureRandom();
    byte[] code = new byte[32];
    sr.nextBytes(code);
    return Base64.encodeToString(code, Base64.URL_SAFE | Base64.NO_WRAP | Base64.NO_PADDING);
  }

  public static String generateCodeChallenge(String codeVerifier) throws NoSuchAlgorithmException {
    byte[] bytes = codeVerifier.getBytes();
    MessageDigest md = MessageDigest.getInstance("SHA-256");
    md.update(bytes);
    byte[] digest = md.digest();
    return Base64.encodeToString(digest, Base64.URL_SAFE | Base64.NO_WRAP | Base64.NO_PADDING);
  }
}