// Copyright 2013 Google Inc. All Rights Reserved.
//
// 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.
//
// Functions for streaming input and output.

#include <string.h>
#include <unistd.h>
#include "./streams.h"

#if defined(__cplusplus) || defined(c_plusplus)
extern "C" {
#endif

int BrotliMemInputFunction(void* data, uint8_t* buf, size_t count) {
  BrotliMemInput* input = (BrotliMemInput*)data;
  if (input->pos > input->length) {
    return -1;
  }
  if (input->pos + count > input->length) {
    count = input->length - input->pos;
  }
  memcpy(buf, input->buffer + input->pos, count);
  input->pos += count;
  return count;
}

BrotliInput BrotliInitMemInput(const uint8_t* buffer, size_t length,
                               BrotliMemInput* mem_input) {
  mem_input->buffer = buffer;
  mem_input->length = length;
  mem_input->pos = 0;
  BrotliInput input;
  input.cb_ = &BrotliMemInputFunction;
  input.data_ = mem_input;
  return input;
}

int BrotliMemOutputFunction(void* data, const uint8_t* buf, size_t count) {
  BrotliMemOutput* output = (BrotliMemOutput*)data;
  if (output->pos + count > output->length) {
    return -1;
  }
  memcpy(output->buffer + output->pos, buf, count);
  output->pos += count;
  return count;
}

BrotliOutput BrotliInitMemOutput(uint8_t* buffer, size_t length,
                                 BrotliMemOutput* mem_output) {
  mem_output->buffer = buffer;
  mem_output->length = length;
  mem_output->pos = 0;
  BrotliOutput output;
  output.cb_ = &BrotliMemOutputFunction;
  output.data_ = mem_output;
  return output;
}

int BrotliStdinInputFunction(void* data, uint8_t* buf, size_t count) {
  return read(STDIN_FILENO, buf, count);
}

BrotliInput BrotliStdinInput() {
  BrotliInput in;
  in.cb_ = BrotliStdinInputFunction;
  in.data_ = NULL;
  return in;
}

int BrotliStdoutOutputFunction(void* data, const uint8_t* buf, size_t count) {
  return write(STDOUT_FILENO, buf, count);
}

BrotliOutput BrotliStdoutOutput() {
  BrotliOutput out;
  out.cb_ = BrotliStdoutOutputFunction;
  out.data_ = NULL;
  return out;
}

int BrotliFileOutputFunction(void* data, const uint8_t* buf, size_t count) {
  return fwrite(buf, 1, count, (FILE*)data);
}

BrotliOutput BrotliFileOutput(FILE* f) {
  BrotliOutput out;
  out.cb_ = BrotliFileOutputFunction;
  out.data_ = f;
  return out;
}


#if defined(__cplusplus) || defined(c_plusplus)
}    // extern "C"
#endif