Add a CLI

The CLI can be used like this:

    $ nsfw path/to/watch

It should help for testing nsfw and reporting issues.

nsfw.js

@@ -0,0 +1,81 @@
+#!/usr/bin/env node
+/* eslint no-console: 0 */
+
+const path = require('path');
+const nsfw = require('./lib/src/index.js');
+
+function usage () {
+  console.log('Usage: nsfw <pattern> [<pattern>...] [options]');
+  console.log('  -h, --help\tShow help');
+  console.log('  -v, --verbose\tMake output more verbose');
+}
+
+function start (dirs, verbose) {
+  console.log('verbose', verbose);
+  console.log('dirs', dirs);
+
+  const options = {
+    errorCallback: function (err) {
+      console.error('Error:', err);
+    }
+  };
+
+  const eventCallback = function (events) {
+    events.forEach(function (event) {
+      switch (event.action) {
+      case nsfw.actions.CREATED:
+        console.log('Created:', path.join(event.directory, event.file));
+        break;
+      case nsfw.actions.DELETED:
+        console.log('Deleted:', path.join(event.directory, event.file));
+        break;
+      case nsfw.actions.MODIFIED:
+        if (verbose) {
+          console.log('Modified:', path.join(event.directory, event.file));
+        }
+        break;
+      case nsfw.actions.RENAMED:
+        console.log('Renamed:', path.join(event.directory, event.oldFile), '→', event.newFile);
+        break;
+      }
+    });
+  };
+
+  dirs.forEach(function (dir) {
+    nsfw(dir, eventCallback, options).then(function (watcher) {
+      if (verbose) {
+        console.log('Watching', dir);
+      }
+      return watcher.start();
+    });
+  });
+}
+
+function main (argv) {
+  const dirs = [];
+  let verbose = false;
+
+  argv.forEach(function (arg, i) {
+    if (i === 0) {
+      return;
+    }
+    if (i === 1 && path.basename(argv[0]) === 'node') {
+      return;
+    }
+    if (arg === '-h' || arg === '--help') {
+      return usage();
+    } else if (arg === '-v' || arg === '--verbose') {
+      verbose = true;
+    } else {
+      dirs.push(arg);
+    }
+  });
+
+  if (dirs.length === 0) {
+    return usage();
+  }
+
+  start(dirs, verbose);
+}
+
+main(process.argv);

package.json

@@ -19,7 +19,9 @@
   "bugs": {
     "url": "https://github.com/axosoft/node-simple-file-watcher/issues"
   },
+  "bin": "nsfw.js",
   "files": [
+    "nsfw.js",
     "lib",
     "src",
     "includes",