/* prettier-ignore */

/********************************************************************************
 *   Ledger Communication toolkit
 *   (c) 2016 Ledger
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 ********************************************************************************/

'use strict';

// MEW - Require u2f instead of expecting it in global scope
var u2f = require('./u2f-api');

var LedgerEth = function(comm) {
  this.comm = comm;
};

//MEW - Add error handling method
LedgerEth.prototype.getError = function(err) {
  return err.errorCode
    ? u2f.getErrorByCode(err.errorCode)
    : err;
};

LedgerEth.splitPath = function(path) {
  var result = [];
  var components = path.split('/');
  components.forEach(function(element, index) {
    var number = parseInt(element, 10);
    if (isNaN(number)) {
      return;
    }
    if (element.length > 1 && element[element.length - 1] == "'") {
      number += 0x80000000;
    }
    result.push(number);
  });
  return result;
};

// callback is function(response, error)
LedgerEth.prototype.getAddress = function(
  path,
  callback,
  boolDisplay,
  boolChaincode
) {
  var splitPath = LedgerEth.splitPath(path);
  var buffer = new Buffer(5 + 1 + splitPath.length * 4);
  buffer[0] = 0xe0;
  buffer[1] = 0x02;
  buffer[2] = boolDisplay ? 0x01 : 0x00;
  buffer[3] = boolChaincode ? 0x01 : 0x00;
  buffer[4] = 1 + splitPath.length * 4;
  buffer[5] = splitPath.length;
  splitPath.forEach(function(element, index) {
    buffer.writeUInt32BE(element, 6 + 4 * index);
  });
  var self = this;
  var localCallback = function(response, error) {
    if (typeof error != 'undefined') {
      callback(undefined, error);
    } else {
      var result = {};
      response = new Buffer(response, 'hex');
      var sw = response.readUInt16BE(response.length - 2);
      if (sw != 0x9000) {
        callback(
          undefined,
          'Invalid status ' +
            sw.toString(16) +
            '. Check to make sure the right application is selected ?'
        );
        return;
      }
      var publicKeyLength = response[0];
      var addressLength = response[1 + publicKeyLength];
      result['publicKey'] = response
        .slice(1, 1 + publicKeyLength)
        .toString('hex');
      result['address'] =
        '0x' +
        response
          .slice(
            1 + publicKeyLength + 1,
            1 + publicKeyLength + 1 + addressLength
          )
          .toString('ascii');
      if (boolChaincode) {
        result['chainCode'] = response
          .slice(
            1 + publicKeyLength + 1 + addressLength,
            1 + publicKeyLength + 1 + addressLength + 32
          )
          .toString('hex');
      }
      callback(result);
    }
  };
  this.comm.exchange(buffer.toString('hex'), localCallback);
};

// callback is function(response, error)
LedgerEth.prototype.signTransaction = function(path, rawTxHex, callback) {
  var splitPath = LedgerEth.splitPath(path);
  var offset = 0;
  var rawTx = new Buffer(rawTxHex, 'hex');
  var apdus = [];
  while (offset != rawTx.length) {
    var maxChunkSize = offset == 0 ? 150 - 1 - splitPath.length * 4 : 150;
    var chunkSize =
      offset + maxChunkSize > rawTx.length
        ? rawTx.length - offset
        : maxChunkSize;
    var buffer = new Buffer(
      offset == 0 ? 5 + 1 + splitPath.length * 4 + chunkSize : 5 + chunkSize
    );
    buffer[0] = 0xe0;
    buffer[1] = 0x04;
    buffer[2] = offset == 0 ? 0x00 : 0x80;
    buffer[3] = 0x00;
    buffer[4] = offset == 0 ? 1 + splitPath.length * 4 + chunkSize : chunkSize;
    if (offset == 0) {
      buffer[5] = splitPath.length;
      splitPath.forEach(function(element, index) {
        buffer.writeUInt32BE(element, 6 + 4 * index);
      });
      rawTx.copy(buffer, 6 + 4 * splitPath.length, offset, offset + chunkSize);
    } else {
      rawTx.copy(buffer, 5, offset, offset + chunkSize);
    }
    apdus.push(buffer.toString('hex'));
    offset += chunkSize;
  }
  var self = this;
  var localCallback = function(response, error) {
    if (typeof error != 'undefined') {
      callback(undefined, error);
    } else {
      response = new Buffer(response, 'hex');
      var sw = response.readUInt16BE(response.length - 2);
      if (sw != 0x9000) {
        callback(
          undefined,
          'Invalid status ' +
            sw.toString(16) +
            '. Check to make sure contract data is on ?'
        );
        return;
      }
      if (apdus.length == 0) {
        var result = {};
        result['v'] = response.slice(0, 1).toString('hex');
        result['r'] = response.slice(1, 1 + 32).toString('hex');
        result['s'] = response.slice(1 + 32, 1 + 32 + 32).toString('hex');
        callback(result);
      } else {
        self.comm.exchange(apdus.shift(), localCallback);
      }
    }
  };
  self.comm.exchange(apdus.shift(), localCallback);
};

// callback is function(response, error)
LedgerEth.prototype.getAppConfiguration = function(callback) {
  var buffer = new Buffer(5);
  buffer[0] = 0xe0;
  buffer[1] = 0x06;
  buffer[2] = 0x00;
  buffer[3] = 0x00;
  buffer[4] = 0x00;
  var localCallback = function(response, error) {
    if (typeof error != 'undefined') {
      callback(undefined, error);
    } else {
      response = new Buffer(response, 'hex');
      var result = {};
      var sw = response.readUInt16BE(response.length - 2);
      if (sw != 0x9000) {
        callback(
          undefined,
          'Invalid status ' +
            sw.toString(16) +
            '. Check to make sure the right application is selected ?'
        );
        return;
      }
      result['arbitraryDataEnabled'] = response[0] & 0x01;
      result['version'] =
        '' + response[1] + '.' + response[2] + '.' + response[3];
      callback(result);
    }
  };
  this.comm.exchange(buffer.toString('hex'), localCallback);
};

LedgerEth.prototype.signPersonalMessage_async = function(
  path,
  messageHex,
  callback
) {
  var splitPath = LedgerEth.splitPath(path);
  var offset = 0;
  var message = new Buffer(messageHex, 'hex');
  var apdus = [];
  var response = [];
  var self = this;
  while (offset != message.length) {
    var maxChunkSize = offset == 0 ? 150 - 1 - splitPath.length * 4 - 4 : 150;
    var chunkSize =
      offset + maxChunkSize > message.length
        ? message.length - offset
        : maxChunkSize;
    var buffer = new Buffer(
      offset == 0 ? 5 + 1 + splitPath.length * 4 + 4 + chunkSize : 5 + chunkSize
    );
    buffer[0] = 0xe0;
    buffer[1] = 0x08;
    buffer[2] = offset == 0 ? 0x00 : 0x80;
    buffer[3] = 0x00;
    buffer[4] =
      offset == 0 ? 1 + splitPath.length * 4 + 4 + chunkSize : chunkSize;
    if (offset == 0) {
      buffer[5] = splitPath.length;
      splitPath.forEach(function(element, index) {
        buffer.writeUInt32BE(element, 6 + 4 * index);
      });
      buffer.writeUInt32BE(message.length, 6 + 4 * splitPath.length);
      message.copy(
        buffer,
        6 + 4 * splitPath.length + 4,
        offset,
        offset + chunkSize
      );
    } else {
      message.copy(buffer, 5, offset, offset + chunkSize);
    }
    apdus.push(buffer.toString('hex'));
    offset += chunkSize;
  }
  var self = this;
  var localCallback = function(response, error) {
    if (typeof error != 'undefined') {
      callback(undefined, error);
    } else {
      response = new Buffer(response, 'hex');
      var sw = response.readUInt16BE(response.length - 2);
      if (sw != 0x9000) {
        callback(
          undefined,
          'Invalid status ' +
            sw.toString(16) +
            '. Check to make sure the right application is selected ?'
        );
        return;
      }
      if (apdus.length == 0) {
        var result = {};
        result['v'] = response.slice(0, 1).toString('hex');
        result['r'] = response.slice(1, 1 + 32).toString('hex');
        result['s'] = response.slice(1 + 32, 1 + 32 + 32).toString('hex');
        callback(result);
      } else {
        self.comm.exchange(apdus.shift(), localCallback);
      }
    }
  };
  self.comm.exchange(apdus.shift(), localCallback);
};

module.exports = LedgerEth;