var common = require('./common');
var fs = require('fs');

//@
//@ ### cat(file [, file ...])
//@ ### cat(file_array)
//@
//@ Examples:
//@
//@ ```javascript
//@ var str = cat('file*.txt');
//@ var str = cat('file1', 'file2');
//@ var str = cat(['file1', 'file2']); // same as above
//@ ```
//@
//@ Returns a string containing the given file, or a concatenated string
//@ containing the files if more than one file is given (a new line character is
//@ introduced between each file). Wildcard `*` accepted.
function _cat(options, files) {
  var cat = '';

  if (!files)
    common.error('no paths given');

  if (typeof files === 'string')
    files = [].slice.call(arguments, 1);
  // if it's array leave it as it is

  files = common.expand(files);

  files.forEach(function(file) {
    if (!fs.existsSync(file))
      common.error('no such file or directory: ' + file);

    cat += fs.readFileSync(file, 'utf8') + '\n';
  });

  if (cat[cat.length-1] === '\n')
    cat = cat.substring(0, cat.length-1);

  return common.ShellString(cat);
}
module.exports = _cat;