var O_READ = 'READ';
var O_WRITE = 'WRITE';
var O_CREATE = 'CREATE';
var O_EXCLUSIVE = 'EXCLUSIVE';
var O_TRUNCATE = 'TRUNCATE';
var O_APPEND = 'APPEND';
var XATTR_CREATE = 'CREATE';
var XATTR_REPLACE = 'REPLACE';

module.exports = {
  FILE_SYSTEM_NAME: 'local',

  FILE_STORE_NAME: 'files',

  IDB_RO: 'readonly',
  IDB_RW: 'readwrite',

  WSQL_VERSION: '1',
  WSQL_SIZE: 5 * 1024 * 1024,
  WSQL_DESC: 'FileSystem Storage',

  NODE_TYPE_FILE: 'FILE',
  NODE_TYPE_DIRECTORY: 'DIRECTORY',
  NODE_TYPE_SYMBOLIC_LINK: 'SYMLINK',
  NODE_TYPE_META: 'META',


  DEFAULT_DIR_PERMISSIONS: 0x1ED, // 755
  DEFAULT_FILE_PERMISSIONS: 0x1A4, // 644
  FULL_READ_WRITE_EXEC_PERMISSIONS: 0x1FF, // 777
  READ_WRITE_PERMISSIONS: 0x1B6, /// 666
  
  SYMLOOP_MAX: 10,

  BINARY_MIME_TYPE: 'application/octet-stream',
  JSON_MIME_TYPE: 'application/json',

  ROOT_DIRECTORY_NAME: '/', // basename(normalize(path))

  // FS Mount Flags
  FS_FORMAT: 'FORMAT',
  FS_NOCTIME: 'NOCTIME',
  FS_NOMTIME: 'NOMTIME',
  FS_NODUPEIDCHECK: 'FS_NODUPEIDCHECK',

  // FS File Open Flags
  O_READ: O_READ,
  O_WRITE: O_WRITE,
  O_CREATE: O_CREATE,
  O_EXCLUSIVE: O_EXCLUSIVE,
  O_TRUNCATE: O_TRUNCATE,
  O_APPEND: O_APPEND,

  O_FLAGS: {
    'r': [O_READ],
    'r+': [O_READ, O_WRITE],
    'w': [O_WRITE, O_CREATE, O_TRUNCATE],
    'w+': [O_WRITE, O_READ, O_CREATE, O_TRUNCATE],
    'wx': [O_WRITE, O_CREATE, O_EXCLUSIVE, O_TRUNCATE],
    'wx+': [O_WRITE, O_READ, O_CREATE, O_EXCLUSIVE, O_TRUNCATE],
    'a': [O_WRITE, O_CREATE, O_APPEND],
    'a+': [O_WRITE, O_READ, O_CREATE, O_APPEND],
    'ax': [O_WRITE, O_CREATE, O_EXCLUSIVE, O_APPEND],
    'ax+': [O_WRITE, O_READ, O_CREATE, O_EXCLUSIVE, O_APPEND]
  },

  XATTR_CREATE: XATTR_CREATE,
  XATTR_REPLACE: XATTR_REPLACE,

  FS_READY: 'READY',
  FS_PENDING: 'PENDING',
  FS_ERROR: 'ERROR',

  SUPER_NODE_ID: '00000000-0000-0000-0000-000000000000',

  // Reserved File Descriptors for streams
  STDIN: 0,
  STDOUT: 1,
  STDERR: 2,
  FIRST_DESCRIPTOR: 3,

  ENVIRONMENT: {
    TMP: '/tmp',
    PATH: ''
  },

  // Duplicate Node's fs.constants
  fsConstants: {
    O_RDONLY: 0,
    O_WRONLY: 1,
    O_RDWR: 2,
    S_IFMT: 61440,
    S_IFREG: 32768,
    S_IFDIR: 16384,
    S_IFCHR: 8192,
    S_IFBLK: 24576,
    S_IFIFO: 4096,
    S_IFLNK: 40960,
    S_IFSOCK: 49152,
    O_CREAT: 512,
    O_EXCL: 2048,
    O_NOCTTY: 131072,
    O_TRUNC: 1024,
    O_APPEND: 8,
    O_DIRECTORY: 1048576,
    O_NOFOLLOW: 256,
    O_SYNC: 128,
    O_DSYNC: 4194304,
    O_SYMLINK: 2097152,
    O_NONBLOCK: 4,
    S_IRWXU: 448,
    S_IRUSR: 256,
    S_IWUSR: 128,
    S_IXUSR: 64,
    S_IRWXG: 56,
    S_IRGRP: 32,
    S_IWGRP: 16,
    S_IXGRP: 8,
    S_IRWXO: 7,
    S_IROTH: 4,
    S_IWOTH: 2,
    S_IXOTH: 1,
    F_OK: 0,
    R_OK: 4,
    W_OK: 2,
    X_OK: 1,
    UV_FS_COPYFILE_EXCL: 1,
    COPYFILE_EXCL: 1
  }
};