// Copyright 2016, 2017 Lovell Fuller and contributors.
//
// 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.

#include <node.h>
#include <node_buffer.h>
#include <nan.h>
#include "shoco/shoco.h"

static const char shorterErrorMemory[] = "Memory allocated was shorter than necessary";

NAN_METHOD(compressBuffer) {
  Nan::HandleScope();

  const v8::Local<v8::Object> input = info[0].As<v8::Object>();
  const size_t inputLength = node::Buffer::Length(input);
  const size_t outputLengthMax = inputLength * 2 + 1;

  char *output = new char[outputLengthMax];
  size_t outputLength = shoco_compress(node::Buffer::Data(input),
    inputLength, output, outputLengthMax);

  if (outputLengthMax > outputLength) {
    info
      .GetReturnValue()
      .Set(Nan::CopyBuffer(output, outputLength).ToLocalChecked());
    delete[] output;
  } else {
    delete[] output;
    Nan::ThrowError(shorterErrorMemory);
  }
}

NAN_METHOD(compressString) {
  Nan::HandleScope();

  const size_t inputLength = Nan::Utf8String(info[0]).length();
  const size_t outputLengthMax = inputLength * 2 + 1;

  char *output = new char[outputLengthMax];
  size_t outputLength = shoco_compress(*Nan::Utf8String(info[0]),
    inputLength, output, outputLengthMax);

  if (outputLengthMax > outputLength) {
    info
      .GetReturnValue()
      .Set(Nan::CopyBuffer(output, outputLength).ToLocalChecked());
    delete[] output;
  } else {
    delete[] output;
    Nan::ThrowError(shorterErrorMemory);
  }
}

NAN_METHOD(decompress) {
  Nan::HandleScope();

  const v8::Local<v8::Object> input = info[0].As<v8::Object>();
  const size_t inputLength = node::Buffer::Length(input);
  const size_t outputLengthMax = inputLength * 3;

  char *output = new char[outputLengthMax];
  size_t outputLength = shoco_decompress(node::Buffer::Data(input),
    inputLength, output, outputLengthMax);

  if (outputLengthMax > outputLength) {
    info
      .GetReturnValue()
      .Set(Nan::New(output, outputLength).ToLocalChecked());
    delete[] output;
  } else {
    delete[] output;
    Nan::ThrowError(shorterErrorMemory);
  }
}

NAN_MODULE_INIT(init) {
  Nan::Set(target, Nan::New("compressBuffer").ToLocalChecked(),
    Nan::GetFunction(Nan::New<v8::FunctionTemplate>(compressBuffer)).ToLocalChecked());
  Nan::Set(target, Nan::New("compressString").ToLocalChecked(),
    Nan::GetFunction(Nan::New<v8::FunctionTemplate>(compressString)).ToLocalChecked());
  Nan::Set(target, Nan::New("decompress").ToLocalChecked(),
    Nan::GetFunction(Nan::New<v8::FunctionTemplate>(decompress)).ToLocalChecked());
}

NODE_MODULE(shorter, init)