#!/usr/bin/env node

var Emitter = require('events').EventEmitter,
  forEach = require('async-foreach').forEach,
  Gaze = require('gaze'),
  meow = require('meow'),
  util = require('util'),
  path = require('path'),
  glob = require('glob'),
  sass = require('../lib'),
  render = require('../lib/render'),
  watcher = require('../lib/watcher'),
  stdout = require('stdout-stream'),
  stdin = require('get-stdin'),
  fs = require('fs');

/**
 * Initialize CLI
 */

var cli = meow(`
    Usage:
      node-sass [options] <input.scss>
      cat <input.scss> | node-sass [options] > output.css

    Example: Compile foobar.scss to foobar.css
      node-sass --output-style compressed foobar.scss > foobar.css
      cat foobar.scss | node-sass --output-style compressed > foobar.css

    Example: Watch the sass directory for changes, compile with sourcemaps to the css directory
      node-sass --watch --recursive --output css
        --source-map true --source-map-contents sass

    Options
      -w, --watch                Watch a directory or file
      -r, --recursive            Recursively watch directories or files
      -o, --output               Output directory
      -x, --omit-source-map-url  Omit source map URL comment from output
      -i, --indented-syntax      Treat data from stdin as sass code (versus scss)
      -q, --quiet                Suppress log output except on error
      -v, --version              Prints version info
      --output-style             CSS output style (nested | expanded | compact | compressed)
      --indent-type              Indent type for output CSS (space | tab)
      --indent-width             Indent width; number of spaces or tabs (maximum value: 10)
      --linefeed                 Linefeed style (cr | crlf | lf | lfcr)
      --source-comments          Include debug info in output
      --source-map               Emit source map (boolean, or path to output .map file)
      --source-map-contents      Embed include contents in map
      --source-map-embed         Embed sourceMappingUrl as data URI
      --source-map-root          Base path, will be emitted in source-map as is
      --include-path             Path to look for imported files
      --follow                   Follow symlinked directories
      --precision                The amount of precision allowed in decimal numbers
      --error-bell               Output a bell character on errors
      --importer                 Path to .js file containing custom importer
      --functions                Path to .js file containing custom functions
      --help                     Print usage info
`, {
  version: sass.info,
  flags: {
    errorBell: {
      type: 'boolean',
    },
    functions: {
      type: 'string',
    },
    follow: {
      type: 'boolean',
    },
    importer: {
      type: 'string',
    },
    includePath: {
      type: 'string',
      default: [process.cwd()],
      isMultiple: true,
    },
    indentType: {
      type: 'string',
      default: 'space',
    },
    indentWidth: {
      type: 'number',
      default: 2,
    },
    indentedSyntax: {
      type: 'boolean',
      alias: 'i',
    },
    linefeed: {
      type: 'string',
      default: 'lf',
    },
    omitSourceMapUrl: {
      type: 'boolean',
      alias: 'x',
    },
    output: {
      type: 'string',
      alias: 'o',
    },
    outputStyle: {
      type: 'string',
      default: 'nested',
    },
    precision: {
      type: 'number',
      default: 5,
    },
    quiet: {
      type: 'boolean',
      default: false,
      alias: 'q',
    },
    recursive: {
      type: 'boolean',
      default: true,
      alias: 'r',
    },
    sourceMapContents: {
      type: 'boolean',
    },
    sourceMapEmbed: {
      type: 'boolean',
    },
    sourceMapRoot: {
      type: 'string',
    },
    sourceComments: {
      type: 'boolean',
      alias: 'c',
    },
    version: {
      type: 'boolean',
      alias: 'v',
    },
    watch: {
      type: 'boolean',
      alias: 'w',
    },
  },
});

/**
 * Is a Directory
 *
 * @param {String} filePath
 * @returns {Boolean}
 * @api private
 */

function isDirectory(filePath) {
  var isDir = false;
  try {
    var absolutePath = path.resolve(filePath);
    isDir = fs.statSync(absolutePath).isDirectory();
  } catch (e) {
    isDir = e.code === 'ENOENT';
  }
  return isDir;
}

/**
 * Get correct glob pattern
 *
 * @param {Object} options
 * @returns {String}
 * @api private
 */

function globPattern(options) {
  return options.recursive ? '**/*.{sass,scss}' : '*.{sass,scss}';
}

/**
 * Create emitter
 *
 * @api private
 */

function getEmitter() {
  var emitter = new Emitter();

  emitter.on('error', function(err) {
    if (options.errorBell) {
      err += '\x07';
    }
    console.error(err);
    if (!options.watch) {
      process.exit(1);
    }
  });

  emitter.on('warn', function(data) {
    if (!options.quiet) {
      console.warn(data);
    }
  });

  emitter.on('info', function(data) {
    if (!options.quiet) {
      console.info(data);
    }
  });

  emitter.on('log', stdout.write.bind(stdout));

  return emitter;
}

/**
 * Construct options
 *
 * @param {Array} arguments
 * @param {Object} options
 * @api private
 */

function getOptions(args, options) {
  var cssDir, sassDir, file, mapDir;
  options.src = args[0];

  if (args[1]) {
    options.dest = path.resolve(args[1]);
  } else if (options.output) {
    options.dest = path.join(
      path.resolve(options.output),
      [path.basename(options.src, path.extname(options.src)), '.css'].join(''));  // replace ext.
  }

  if (options.directory) {
    sassDir = path.resolve(options.directory);
    file = path.relative(sassDir, args[0]);
    cssDir = path.resolve(options.output);
    options.dest = path.join(cssDir, file).replace(path.extname(file), '.css');
  }

  if (options.sourceMap) {
    if(!options.sourceMapOriginal) {
      options.sourceMapOriginal = options.sourceMap;
    }

    if (options.sourceMapOriginal === 'true') {
      options.sourceMap = options.dest + '.map';
    } else {
      // check if sourceMap path ends with .map to avoid isDirectory false-positive
      var sourceMapIsDirectory = options.sourceMapOriginal.indexOf('.map', options.sourceMapOriginal.length - 4) === -1 && isDirectory(options.sourceMapOriginal);

      if (!sourceMapIsDirectory) {
        options.sourceMap = path.resolve(options.sourceMapOriginal);
      } else if (!options.directory) {
        options.sourceMap = path.resolve(options.sourceMapOriginal, path.basename(options.dest) + '.map');
      } else {
        sassDir = path.resolve(options.directory);
        file = path.relative(sassDir, args[0]);
        mapDir = path.resolve(options.sourceMapOriginal);
        options.sourceMap = path.join(mapDir, file).replace(path.extname(file), '.css.map');
      }
    }
  }

  return options;
}

/**
 * Watch
 *
 * @param {Object} options
 * @param {Object} emitter
 * @api private
 */

function watch(options, emitter) {
  var handler = function(files) {
    files.added.forEach(function(file) {
      var watch = gaze.watched();
      Object.keys(watch).forEach(function (dir) {
        if (watch[dir].indexOf(file) !== -1) {
          gaze.add(file);
        }
      });
    });

    files.changed.forEach(function(file) {
      if (path.basename(file)[0] !== '_') {
        renderFile(file, options, emitter);
      }
    });

    files.removed.forEach(function(file) {
      gaze.remove(file);
    });
  };

  var gaze = new Gaze();
  gaze.add(watcher.reset(options));
  gaze.on('error', emitter.emit.bind(emitter, 'error'));

  gaze.on('changed', function(file) {
    handler(watcher.changed(file));
  });

  gaze.on('added', function(file) {
    handler(watcher.added(file));
  });

  gaze.on('deleted', function(file) {
    handler(watcher.removed(file));
  });
}

/**
 * Run
 *
 * @param {Object} options
 * @param {Object} emitter
 * @api private
 */

function run(options, emitter) {
  if (options.directory) {
    if (!options.output) {
      emitter.emit('error', 'An output directory must be specified when compiling a directory');
    }
    if (!isDirectory(options.output)) {
      emitter.emit('error', 'An output directory must be specified when compiling a directory');
    }
  }

  if (options.sourceMapOriginal && options.directory && !isDirectory(options.sourceMapOriginal) && options.sourceMapOriginal !== 'true') {
    emitter.emit('error', 'The --source-map option must be either a boolean or directory when compiling a directory');
  }

  if (options.importer) {
    if ((path.resolve(options.importer) === path.normalize(options.importer).replace(/(.+)([/|\\])$/, '$1'))) {
      options.importer = require(options.importer);
    } else {
      options.importer = require(path.resolve(options.importer));
    }
  }

  if (options.functions) {
    if ((path.resolve(options.functions) === path.normalize(options.functions).replace(/(.+)([/|\\])$/, '$1'))) {
      options.functions = require(options.functions);
    } else {
      options.functions = require(path.resolve(options.functions));
    }
  }

  if (options.watch) {
    watch(options, emitter);
  } else if (options.directory) {
    renderDir(options, emitter);
  } else {
    render(options, emitter);
  }
}

/**
 * Render a file
 *
 * @param {String} file
 * @param {Object} options
 * @param {Object} emitter
 * @api private
 */
function renderFile(file, options, emitter) {
  options = getOptions([path.resolve(file)], options);
  if (options.watch && !options.quiet) {
    emitter.emit('info', util.format('=> changed: %s', file));
  }
  render(options, emitter);
}

/**
 * Render all sass files in a directory
 *
 * @param {Object} options
 * @param {Object} emitter
 * @api private
 */
function renderDir(options, emitter) {
  var globPath = path.resolve(options.directory, globPattern(options));
  glob(globPath, { ignore: '**/_*', follow: options.follow }, function(err, files) {
    if (err) {
      return emitter.emit('error', util.format('You do not have permission to access this path: %s.', err.path));
    } else if (!files.length) {
      return emitter.emit('error', 'No input file was found.');
    }

    forEach(files, function(subject) {
      emitter.once('done', this.async());
      renderFile(subject, options, emitter);
    }, function(successful, arr) {
      var outputDir = path.join(process.cwd(), options.output);
      if (!options.quiet) {
        emitter.emit('info', util.format('Wrote %s CSS files to %s', arr.length, outputDir));
      }
      process.exit();
    });
  });
}

/**
 * Arguments and options
 */

var options = getOptions(cli.input, cli.flags);
var emitter = getEmitter();

/**
 * Show usage if no arguments are supplied
 */

if (!options.src && process.stdin.isTTY) {
  emitter.emit('error', [
    'Provide a Sass file to render',
    '',
    'Example: Compile foobar.scss to foobar.css',
    '  node-sass --output-style compressed foobar.scss > foobar.css',
    '  cat foobar.scss | node-sass --output-style compressed > foobar.css',
    '',
    'Example: Watch the sass directory for changes, compile with sourcemaps to the css directory',
    '  node-sass --watch --recursive --output css',
    '    --source-map true --source-map-contents sass',
  ].join('\n'));
}

/**
 * Apply arguments
 */

if (options.src) {
  if (isDirectory(options.src)) {
    options.directory = options.src;
  }
  run(options, emitter);
} else if (!process.stdin.isTTY) {
  stdin(function(data) {
    options.data = data;
    options.stdin = true;
    run(options, emitter);
  });
}