/* Copyright (c) 2021 Xie Meiyi(xiemeiyi@hust.edu.cn) and OceanBase and/or its affiliates. All rights reserved.
miniob is licensed under Mulan PSL v2.
You can use this software according to the terms and conditions of the Mulan PSL v2.
You may obtain a copy of Mulan PSL v2 at:
         http://license.coscl.org.cn/MulanPSL2
THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
See the Mulan PSL v2 for more details. */

//
// Created by Longda on 2010
//

#include <dirent.h>
#include <iostream>
#include <stdio.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>

#include "common/io/io.h"
#include "common/lang/string.h"
#include "common/log/log.h"
#include "common/math/regex.h"
#include "common/mm/mem.h"

namespace common {

int readFromFile(const std::string &fileName, char *&outputData, size_t &fileSize)
{
  FILE *file = fopen(fileName.c_str(), "rb");
  if (file == NULL) {
    std::cerr << "Failed to open file " << fileName << SYS_OUTPUT_FILE_POS << SYS_OUTPUT_ERROR << std::endl;
    return -1;
  }

  // fseek( file, 0, SEEK_END );
  // size_t fsSize = ftell( file );
  // fseek( file, 0, SEEK_SET );

  char buffer[4 * ONE_KILO];
  size_t readSize = 0;
  size_t oneRead = 0;

  char *data = NULL;
  do {
    memset(buffer, 0, sizeof(buffer));
    oneRead = fread(buffer, 1, sizeof(buffer), file);
    if (ferror(file)) {
      std::cerr << "Failed to read data" << fileName << SYS_OUTPUT_FILE_POS << SYS_OUTPUT_ERROR << std::endl;
      fclose(file);
      if (data != NULL) {
        lfree(data);
        data = NULL;
      }
      return -1;
    }

    data = (char *)lrealloc(data, readSize + oneRead);
    if (data == NULL) {
      std::cerr << "Failed to alloc memory for " << fileName << SYS_OUTPUT_FILE_POS << SYS_OUTPUT_ERROR << std::endl;
      lfree(data);
      fclose(file);
      return -1;
    } else {
      memcpy(data + readSize, buffer, oneRead);
      readSize += oneRead;
    }

  } while (feof(file) == 0);

  fclose(file);

  outputData = data;
  fileSize = readSize;
  return 0;
}

int writeToFile(const std::string &fileName, const char *data, u32_t dataSize, const char *openMode)
{
  FILE *file = fopen(fileName.c_str(), openMode);
  if (file == NULL) {
    std::cerr << "Failed to open file " << fileName << SYS_OUTPUT_FILE_POS << SYS_OUTPUT_ERROR << std::endl;
    return -1;
  }

  u32_t leftSize = dataSize;
  const char *buffer = data;
  while (leftSize > 0) {
    int writeCount = fwrite(buffer, 1, leftSize, file);
    if (writeCount <= 0) {
      std::cerr << "Failed to open file " << fileName << SYS_OUTPUT_FILE_POS << SYS_OUTPUT_ERROR << std::endl;
      fclose(file);
      return -1;
    } else {
      leftSize -= writeCount;
      buffer += writeCount;
    }
  }

  fclose(file);

  return 0;
}

int getFileLines(const std::string &fileName, u64_t &lineNum)
{
  lineNum = 0;

  char line[4 * ONE_KILO] = {0};

  std::ifstream ifs(fileName.c_str());
  if (!ifs) {
    return -1;
  }

  while (ifs.good()) {
    line[0] = 0;
    ifs.getline(line, sizeof(line));
    char *lineStrip = strip(line);
    if (strlen(lineStrip)) {
      lineNum++;
    }
  }

  ifs.close();
  return 0;
}

int getFileNum(u64_t &fileNum, const std::string &path, const std::string &pattern, bool recursive)
{
  try {
    DIR *dirp = NULL;
    dirp = opendir(path.c_str());
    if (dirp == NULL) {
      std::cerr << "Failed to opendir " << path << SYS_OUTPUT_FILE_POS << SYS_OUTPUT_ERROR << std::endl;
      return -1;
    }

    std::string fullPath;
    struct dirent *entry = NULL;
    struct stat fs;
    while ((entry = readdir(dirp)) != NULL) {
      // don't care ".", "..", ".****" hidden files
      if (!strncmp(entry->d_name, ".", 1)) {
        continue;
      }

      fullPath = path;
      if (path[path.size() - 1] != FILE_PATH_SPLIT) {
        fullPath += FILE_PATH_SPLIT;
      }
      fullPath += entry->d_name;
      memset(&fs, 0, sizeof(fs));
      if (stat(fullPath.c_str(), &fs) < 0) {
        std::cout << "Failed to stat " << fullPath << SYS_OUTPUT_FILE_POS << SYS_OUTPUT_ERROR << std::endl;
        continue;
      }

      if (fs.st_mode & S_IFDIR) {
        if (recursive == 0) {
          continue;
        }

        if (getFileNum(fileNum, fullPath, pattern, recursive) < 0) {
          closedir(dirp);
          return -1;
        }
      }

      if (!(fs.st_mode & S_IFREG)) {
        // not regular files
        continue;
      }

      if (pattern.empty() == false && regex_match(entry->d_name, pattern.c_str())) {
        // Don't match
        continue;
      }

      fileNum++;
    }

    closedir(dirp);

    return 0;
  } catch (...) {
    std::cerr << "Failed to get file num " << path << SYS_OUTPUT_FILE_POS << SYS_OUTPUT_ERROR << std::endl;
  }
  return -1;
}

int getFileList(std::vector<std::string> &fileList, const std::string &path, const std::string &pattern, bool recursive)
{
  try {
    DIR *dirp = NULL;
    dirp = opendir(path.c_str());
    if (dirp == NULL) {
      std::cerr << "Failed to opendir " << path << SYS_OUTPUT_FILE_POS << SYS_OUTPUT_ERROR << std::endl;
      return -1;
    }

    std::string fullPath;
    struct dirent *entry = NULL;
    struct stat fs;
    while ((entry = readdir(dirp)) != NULL) {
      // don't care ".", "..", ".****" hidden files
      if (!strncmp(entry->d_name, ".", 1)) {
        continue;
      }

      fullPath = path;
      if (path[path.size() - 1] != FILE_PATH_SPLIT) {
        fullPath += FILE_PATH_SPLIT;
      }
      fullPath += entry->d_name;
      memset(&fs, 0, sizeof(fs));
      if (stat(fullPath.c_str(), &fs) < 0) {
        std::cout << "Failed to stat " << fullPath << SYS_OUTPUT_FILE_POS << SYS_OUTPUT_ERROR << std::endl;
        continue;
      }

      if (fs.st_mode & S_IFDIR) {
        if (recursive == 0) {
          continue;
        }

        if (getFileList(fileList, fullPath, pattern, recursive) < 0) {
          closedir(dirp);
          return -1;
        }
      }

      if (!(fs.st_mode & S_IFREG)) {
        // regular files
        continue;
      }

      if (pattern.empty() == false && regex_match(entry->d_name, pattern.c_str())) {
        // Don't match
        continue;
      }

      fileList.push_back(fullPath);
    }

    closedir(dirp);
    return 0;
  } catch (...) {
    std::cerr << "Failed to get file list " << path << SYS_OUTPUT_FILE_POS << SYS_OUTPUT_ERROR << std::endl;
  }
  return -1;
}

int getDirList(std::vector<std::string> &dirList, const std::string &path, const std::string &pattern)
{
  try {
    DIR *dirp = NULL;
    dirp = opendir(path.c_str());
    if (dirp == NULL) {
      std::cerr << "Failed to opendir " << path << SYS_OUTPUT_FILE_POS << SYS_OUTPUT_ERROR << std::endl;
      return -1;
    }

    std::string fullPath;
    struct dirent *entry = NULL;
    struct stat fs;
    while ((entry = readdir(dirp)) != NULL) {
      // don't care ".", "..", ".****" hidden files
      if (!strncmp(entry->d_name, ".", 1)) {
        continue;
      }

      fullPath = path;
      if (path[path.size() - 1] != FILE_PATH_SPLIT) {
        fullPath += FILE_PATH_SPLIT;
      }
      fullPath += entry->d_name;
      memset(&fs, 0, sizeof(fs));
      if (stat(fullPath.c_str(), &fs) < 0) {
        std::cout << "Failed to stat " << fullPath << SYS_OUTPUT_FILE_POS << SYS_OUTPUT_ERROR << std::endl;
        continue;
      }

      if ((fs.st_mode & S_IFDIR) == 0) {
        continue;
      }

      if (pattern.empty() == false && regex_match(entry->d_name, pattern.c_str())) {
        // Don't match
        continue;
      }

      dirList.push_back(fullPath);
    }

    closedir(dirp);
    return 0;
  } catch (...) {
    std::cerr << "Failed to get file list " << path << SYS_OUTPUT_FILE_POS << SYS_OUTPUT_ERROR << std::endl;
  }
  return -1;
}

int touch(const std::string &path)
{
  // CWE367: A check occurs on a file's attributes before
  // the file is used in a privileged operation, but things
  // may have changed

  // struct stat fs;

  // memset(&fs, 0, sizeof(fs));
  // if (stat(path.c_str(), &fs) == 0) {
  //   return 0;
  // }

  // create the file
  FILE *file = fopen(path.c_str(), "a");
  if (file == NULL) {
    return -1;
  }
  fclose(file);
  return 0;
}

int getFileSize(const char *filePath, u64_t &fileLen)
{
  if (filePath == NULL || *filePath == '\0') {
    std::cerr << "invalid filepath" << std::endl;
    return -EINVAL;
  }
  struct stat statBuf;
  memset(&statBuf, 0, sizeof(statBuf));

  int rc = stat(filePath, &statBuf);
  if (rc) {
    std::cerr << "Failed to get stat of " << filePath << "," << errno << ":" << strerror(errno) << std::endl;
    return rc;
  }

  if (S_ISDIR(statBuf.st_mode)) {
    std::cerr << filePath << " is directory " << std::endl;
    return -EINVAL;
  }

  fileLen = statBuf.st_size;
  return 0;
}

int writen(int fd, const void *buf, int size)
{
  const char *tmp = (const char *)buf;
  while ( size > 0) {
    const ssize_t ret = ::write(fd, tmp, size);
    if (ret >= 0) {
      tmp  += ret;
      size -= ret;
      continue;
    }
    const int err = errno;
    if (EAGAIN != err && EINTR != err)
      return err;
   }
  return 0;
}

int readn(int fd, void *buf, int size)
{
  char *tmp = (char *)buf;
  while (size > 0) {
    const ssize_t ret = ::read(fd, tmp, size);
    if (ret > 0) {
      tmp  += ret;
      size -= ret;
      continue;
    }
    if (0 == ret)
      return -1; // end of file

    const int err = errno;
    if (EAGAIN != err && EINTR != err)
      return err;
  }
  return 0;
}
}  // namespace common