var node = false;
var crypto;

if (typeof process != "undefined") {
  crypto = await import('crypto');
  if(typeof crypto.webcrypto != "undefined"){
    crypto = crypto.webcrypto;
    console.log("subtle");
  }else{
    node = true;
    console.log("node crypto");
  }
}else{
  crypto = window.crypto;
}

var asciiList = [];
for (var i = 0; i < 256; i++) {
  asciiList[i]=String.fromCharCode(i);
}


const C = {
  sha256: async (msgBuffer) => {
    return node ? new Uint8Array(crypto.createHash("sha256").update(msgBuffer).digest()) :
      new Uint8Array(await crypto.subtle.digest('SHA-256', msgBuffer));
  },
  random: async (length) => {
    return node ? crypto.randomFillSync(new Uint8Array(length)) :
      crypto.getRandomValues(new Uint8Array(length));
  },
  randomKey: async (length) => {
    return C.decode(await C.random(length));
  },
  encode : (data)=>{
    console.log(data);
    if(node){
      return new Uint8Array(Buffer.from(data,"binary"));
    }else{
      var out = new Uint8Array(data.length);
      for (var i = 0; i < data.length; i++) {
        out[i] = data.charCodeAt(i);
      }
      return out;//new Uint8Array(data.split("").map(d => d.charCodeAt(0)));
    }
  },
  decode : (data)=>{
    if(node){
      return Buffer.from(data).toString("binary");
    }else{
      var out = [];
      var i = 0;
      var limit = i - (i%16);
      while (i < limit) {
        out.push(asciiList[data[i]]+asciiList[data[i+1]]+asciiList[data[i+2]]+asciiList[data[i+3]]+asciiList[data[i+4]]+asciiList[data[i+5]]+asciiList[data[i+6]]+asciiList[data[i+7]]+asciiList[data[i+8]]+asciiList[data[i+9]]+asciiList[data[i+10]]+asciiList[data[i+11]]+asciiList[data[i+12]]+asciiList[data[i+13]]+asciiList[data[i+14]]+asciiList[data[i+15]]);
        i+=16;
      }
      while (i < data.length) {
        out.push(asciiList[data[i]]);
        i++;
      }
      return out.join("");
    }
  },
  atob: (data)=>node?Buffer.from(data,"base64").toString("binary"):atob(data),  //base to ascii
  btoa: (data)=>node?Buffer.from(data,"binary").toString("base64"):btoa(data),  //ascii to base
  pad: (data) => {
    var length = 16 - (data.length % 16);
    var mergedArray = new Uint8Array(data.length+length);
    mergedArray.set(data);
    mergedArray.set(new Uint8Array(length).fill(length), data.length);
    return mergedArray;
  },
  unpad: (data) => {
    return data.slice(0, -data[data.length - 1]);
  },
  AES:{
    bytes_to_key: async (bytes, salt, output = 48) => {
      var data = new Uint8Array([...bytes, ...salt]);
      var key = new Uint8Array();
      var final_key = new Uint8Array();
      while (final_key.length < output) {
        key = await C.sha256(new Uint8Array([...key, ...data]));
        final_key = new Uint8Array([...final_key, ...key]);
      }
      return final_key.slice(0, output);
    },
    encryptData: async (rawdata, rawkey) => {
      var salt = await C.random(8);
      var key_iv = await C.AES.bytes_to_key(rawkey, salt, 32 + 16);
      var key = key_iv.slice(0, 32);
      var iv = key_iv.slice(32);
      var aes;
      if(node){
        let cipher = crypto.createCipheriv('aes-256-cbc', key, iv);
        let encrypted = cipher.update(C.pad(rawdata));
        aes = new Uint8Array(Buffer.concat([encrypted, cipher.final()]));
      }else{
        aes = new Uint8Array(await crypto.subtle.encrypt({name: "AES-CBC",iv},await crypto.subtle.importKey("raw",key,"AES-CBC",true,["encrypt", "decrypt"]),C.pad(rawdata)));
      }
      var mergedArray = new Uint8Array(aes.length+16);
      mergedArray.set([83, 97, 108, 116, 95, 50, 53, 54]);
      mergedArray.set(salt,8);
      mergedArray.set(aes,16);
      return mergedArray;
    },
    encrypt: async (message, passphrase) => {
      var rawdata = C.encode(message);
      var rawkey = C.encode(passphrase);
      var step = await C.AES.encryptData(rawdata,rawkey);
      return C.decode(step);
    },
    decryptData: async (rawdata, rawkey) => {
      var check = [83, 97, 108, 116, 95, 50, 53, 54];
      for (var i = 0; i < check.length; i++) {
        if(check[i]!=rawdata[i])return null;
      }
      var salt = rawdata.slice(8,16);
      var key_iv = await C.AES.bytes_to_key(rawkey, salt, 32 + 16);
      var key = key_iv.slice(0, 32);
      var iv = key_iv.slice(32);
      if(node){
        let cipher = crypto.createDecipheriv('aes-256-cbc', Buffer.from(key), iv);
        let encrypted = cipher.update(rawdata.slice(16));
        return C.unpad(new Uint8Array(Buffer.concat([encrypted, cipher.final()])));
      }else{
        return C.unpad(
          new Uint8Array (await crypto.subtle.decrypt(
            {name: "AES-CBC",iv},
            await crypto.subtle.importKey("raw",key,"AES-CBC",true,["encrypt", "decrypt"]),
            rawdata.slice(16)
          ))
        );
      }
    },
    decrypt: async (message, passphrase) => {
      var rawdata = C.encode(message);
      var rawkey = C.encode(passphrase);
      try {
        var step = await C.AES.decryptData(rawdata,rawkey);
        return C.decode(step);
      } catch (e) {
        return null;
      }
    },
  },
  RSA:{
    generateEncryptionKey: async () =>{
      if(node){
        var { publicKey, privateKey } = crypto.generateKeyPairSync("rsa", {modulusLength: 4096,publicExponent:0x010001,hashAlgorithm:"sha256"});
        return {publicKey: C.decode(new Uint8Array( publicKey.export({type:"spki", format:"der"}))),
                privateKey:C.decode(new Uint8Array(privateKey.export({type:"pkcs8",format:"der"})))};
      }else{
        var keyPair = await crypto.subtle.generateKey(
          {name: "RSA-OAEP",modulusLength: 4096,publicExponent: new Uint8Array([1, 0, 1]),hash: "SHA-256"},
          true,
          ["encrypt", "decrypt"]
        );
        return {privateKey:C.decode(new Uint8Array(await crypto.subtle.exportKey("pkcs8",keyPair.privateKey))),
                publicKey: C.decode(new Uint8Array(await crypto.subtle.exportKey("spki", keyPair.publicKey )))};
      }
    },
    generateSigningKey: async () =>{
      if(node){
        var { publicKey, privateKey } = crypto.generateKeyPairSync("rsa", {modulusLength: 4096,publicExponent:0x010001,hashAlgorithm:"sha256"});
        return {publicKey: C.decode(new Uint8Array( publicKey.export({type:"spki", format:"der"}))),
                privateKey:C.decode(new Uint8Array(privateKey.export({type:"pkcs8",format:"der"})))};
      }else{
        var keyPair = await crypto.subtle.generateKey(
          {name: "RSA-PSS",modulusLength: 4096,publicExponent: new Uint8Array([1, 0, 1]),hash: "SHA-256"},
          true,
          ["sign", "verify"]
        );
        return {privateKey:C.decode(new Uint8Array(await crypto.subtle.exportKey("pkcs8",keyPair.privateKey))),
                publicKey: C.decode(new Uint8Array(await crypto.subtle.exportKey("spki", keyPair.publicKey )))};
      }
    },
    encrypt: async (message, publicKey) => {
      var rawdata = C.encode(message);
      var step;
      if(node){
        var rawkey = crypto.createPublicKey({key:C.encode(publicKey),format:"der",type:"spki"});
        //console.log("d",rawkey);
        step = crypto.publicEncrypt({
          key: rawkey,
          padding: crypto.constants.RSA_PKCS1_OAEP_PADDING,
          oaepHash: "sha256",
        }, Buffer.from(rawdata));
      }else{
        var rawkey = await crypto.subtle.importKey("spki",C.encode(publicKey),{name: "RSA-OAEP",hash: "SHA-256"},true,["encrypt"]);
        step = await crypto.subtle.encrypt({name: "RSA-OAEP"},rawkey,rawdata);
      }
      return C.decode(new Uint8Array(step));
    },
    decrypt: async (message, privateKey) => {
      var rawdata = C.encode(message);
      if(node){
        var rawkey = crypto.createPrivateKey({key:C.encode(privateKey),format:"der",type:"pkcs8"});
        try {
          var step = crypto.privateDecrypt({
            key: rawkey,
            padding: crypto.constants.RSA_PKCS1_OAEP_PADDING,
            oaepHash: "sha256",
          }, Buffer.from(rawdata));
          return C.decode(new Uint8Array(step));
        } catch (e) {
          return null;
        }
      }else{
        var rawkey = await crypto.subtle.importKey("pkcs8",C.encode(privateKey),{name: "RSA-OAEP",hash: "SHA-256"},true,["decrypt"]);
        try {
          var step = await crypto.subtle.decrypt({name: "RSA-OAEP"},rawkey,rawdata);
          return C.decode(new Uint8Array(step));
        } catch (e) {
          console.log(e);
          return null;
        }
      }

    },
    sign:async (message, privateKey) => {
      var rawdata = C.encode(message);
      var step;
      if(node){
        var rawkey = crypto.createPrivateKey({key:C.encode(privateKey),format:"der",type:"pkcs8"});
        step = crypto.sign("sha256", Buffer.from(rawdata), {
          key: rawkey,
          padding: crypto.constants.RSA_PKCS1_PSS_PADDING,
          saltLength:32
        });
      }else{
        var rawkey = await crypto.subtle.importKey("pkcs8",C.encode(privateKey),{name: "RSA-PSS",hash: "SHA-256"},true,["sign"]);
        step = await crypto.subtle.sign(
          {
            name: "RSA-PSS",
            saltLength: 32,
          },
          rawkey,
          rawdata
        );
      }
      return C.decode(new Uint8Array(step));
    },
    verify:async (message, signature, publicKey) => {
      var rawdata = C.encode(message);
      var rawsig = C.encode(signature);
      var step;
      if(node){
        var rawkey = crypto.createPublicKey({key:C.encode(publicKey),format:"der",type:"spki"});
        step = crypto.verify(
          "sha256",
          Buffer.from(rawdata),
          {
            key: rawkey,
            padding: crypto.constants.RSA_PKCS1_PSS_PADDING,
            saltLength:32
          },
          Buffer.from(rawsig)
        );
      }else{
        var rawkey = await crypto.subtle.importKey("spki",C.encode(publicKey),{name: "RSA-PSS",hash: "SHA-256"},true,["verify"]);
        step = await crypto.subtle.verify(
          {
            name: "RSA-PSS",
            saltLength: 32,
          },
          rawkey,
          rawsig,
          rawdata
        );
      }

      return step;// ? "valid" : "invalid";
    }
  },
  communicate:{
    encrypt: async (message,publicKey)=>{
      var randKey = await C.randomKey(32);
      var send = {
        d: await C.AES.encrypt(message,randKey),
        k: await C.RSA.encrypt(randKey,publicKey)
      };
      return {send:JSON.stringify(send),key:randKey};
    },
    decrypt: async (data,privateKey)=>{
      try {
        let {d,k} = JSON.parse(data);
        if(typeof d != "string" || typeof k != "string")throw "invalid Data";
        var randKey = await C.RSA.decrypt(k,privateKey);
        if(randKey == null) throw "invalid async Key";
        var out = await C.AES.decrypt(d,randKey);
        if(out == null) throw "invalid sync Key";
        return {data:out,key:randKey};
      } catch (e) {
        return null;
      }
    },
    //Message to send, reomte publicKey, own privateKey, my id so that the other one knows how i am (can be empty)
    encryptSign: async (message,publicKey,privateKey,id)=>{
      return await C.communicate.encrypt(JSON.stringify({
        d:message,
        i:id,
        s:await C.RSA.sign(message,privateKey)
      }),publicKey);
    },
    //Data to decrypt, my privateKey, callback to get reomtes publicKey with id
    decryptSign: async (data,privateKey,publicKeyCall)=>{
      try {
        var inn = await C.communicate.decrypt(data,privateKey);
        if(inn == null)throw "invalid privateKey";
        inn = JSON.parse(inn);
        if(typeof inn.d == "undefined"||typeof inn.i != "string"||typeof inn.s != "string") throw "invalid Data";
        let {d,i,s} = inn;
        var publicKey = publicKeyCall(i);
        var okay = await C.RSA.verify(d,s,publicKey);
        if(!okay) throw "wrong Public Key";
        return d;
      } catch (e) {
        console.log(e);
        return null;
      }
    },
  }
};

var a = C.sha256;
var b = C.random;
var c = C.randomKey;
var d = C.encode;
var e = C.decode;
var f = C.atob;
var g = C.btoa;
var h = C.pad;
var i = C.unpad;
var j = C.AES;
var k = C.RSA;
var l = C.communicate;

export {
  a as sha256,
  b as random,
  c as randomKey,
  d as encode,
  e as decode,
  f as atob,
  g as btoa,
  h as pad,
  i as unpad,
  j as AES,
  k as RSA,
  l as communicate
};
export default C;