Update to Polymer 2, clean code and add auto build script

.gitignore

@@ -1,7 +1,6 @@
 node_modules
 bower_components
-mock.png
 .*.sw*
 .build*
 jquery.fn.*
-/test
+.vscode

CONTRIBUTING.md

@@ -0,0 +1,51 @@
+# Contributing
+
+This element contains a script to automatically rebuild it for choosen Sortable release.
+
+**TL;DR**
+
+- Change `polymer-sortablejs-template.html` file instead of ~~`polymer-sortablejs.html`~~
+- Run `$ node bower_components/polymer-sortablejs/build.js` to update and rebuild element
+
+## Overview
+
+When _there's an update to Sortable framework_ for which this element is a wraper or you want to _rebuild to include changes you made in template_, you should run `build.js` script inside of element folder with **Node 8** or newer. It will overwrite `polymer-sortable.html` with content of template file `polymer-sortable-template.html` and all options in currently installed Sortable version, excluding those that are defined at the top of `build.js` file.
+
+### Choosing SOrtable version
+
+By default script looks for Sortable files in bower_components and node_modules and will use currently installed verison.  
+If it can't find them, script will download from GitHub (RubaXa/Sortable#master). You can use `-b` to specify branch or `-u` - username from which Sortable will be downloaded.
+
+### Exluding options
+
+On top of `build.js` file there is a constant Array
+
+````javascript
+const DISABLED_PROPERTIES = [
+  'draggable',
+  'setData',
+  'supportPointer'
+];
+````
+
+Those properties will not be included in built file so you either need to manually set them in the element or make sure they aren't nescessary.
+
+### Editing template
+
+You can do whatever you want in the template file as long as you don't remove two comments:
+
+````javascript
+/*properties*/
+
+/*propertyobservers*/
+````
+
+Those two must stay in their places and you mustn't forget they will be overwriten with normal property/function definiton - do not remove commas!
+
+## Pull Requests
+
+Before submitting a Pull Request be sure to run `build.js`.
+
+If you change the code, commit the same message both to the template and generated file if possible.
+
+If you change is only update to latest Sortable, update version in `bower.json` and commit your change as `Rebuilt for Sortable [verison-number]`.

bower.json

@@ -25,7 +25,15 @@
     "tests"
   ],
   "dependencies": {
-    "polymer": "polymer/polymer#^1.6.0",
-    "Sortable": "sortablejs#^1.4.2"
+    "polymer": "polymer/polymer#1.9 - 2",
+    "Sortable": "sortablejs#^1.6.0"
+  },
+  "variants": {
+    "1.x": {
+      "dependencies": {
+        "polymer": "polymer/polymer#1.9",
+        "Sortable": "sortablejs#^1.6.0"
+      }
+    }
   }
 }

build.js

@@ -0,0 +1,182 @@
+const DISABLED_PROPERTIES = [
+  'draggable',
+  'setData',
+  'supportPointer'
+];
+
+
+const fsCallbacks = require('fs'),
+      path = require('path'),
+      https = require('https'),
+      promisify = require('util').promisify;
+
+const fs = {
+  stat: promisify(fsCallbacks.stat),
+  readFile: promisify(fsCallbacks.readFile),
+  writeFile: promisify(fsCallbacks.writeFile),
+  exists: fsCallbacks.existsSync
+};
+
+// From https://stackoverflow.com/a/17676794/6166832
+function donwload(url, dest) {
+  return new Promise((resolve, reject) => {
+    const file = fsCallbacks.createWriteStream(dest),
+          request = http.get(url, response => {
+      response.pipe(file);
+      file.on('finish', () => file.close(reslove));
+    });
+  });
+}
+
+
+// Helper for folder lookup
+function generatePath(depth, ending) {
+  const generatedDepth = new Array(depth).fill('..');
+  return path.join(__dirname, ...generatedDepth, ending);
+}
+
+let found = false;
+
+// Look in bower_components
+for (let depth = 0; depth <= 2; depth++) {
+  if (fs.exists(generatePath(depth, 'bower_components/Sortable/Sortable.js'))) {
+    found = true;
+    console.log('Building from version in bower_components');
+    loadFromFile(generatePath(depth, 'bower_components/Sortable/Sortable.js'));
+    break;
+  }
+}
+
+if (!found) {
+  // Look in node_modules
+  for (let depth = 0; depth <= 2; depth++) {
+    if (fs.exists(generatePath(depth, 'node_modules/Sortable/Sortable.js'))) {
+      found = true;
+      console.log('Building from version in node_modules');
+      loadFromFile(generatePath(depth, 'node_modules/Sortable/Sortable.js'));
+      break;
+    }
+  }
+}
+
+if (!found) {
+  downloadFromGit();
+}
+
+
+async function loadFromFile(filePath) {
+  const file = await fs.readFile(filePath, 'utf8');
+  proceed(file);
+}
+
+async function downloadFromGit() {
+  const gitUsername = process.argv.includes('-u')
+    ? process.argv[process.argv.indexOf('-u') + 1] : 'RubaXa';
+  const gitBranch = process.argv.includes('-b')
+    ? process.argv[process.argv.indexOf('-b') + 1] : 'master';
+  https.get(`https://raw.githubusercontent.com/${gitUsername}/Sortable/${gitBranch}/Sortable.js`, resp => {
+    let data = '';
+    resp.on('data', (chunk) => {
+      data += chunk;
+    });
+    resp.on('end', () => {
+      proceed(data);
+    });
+  }).on("error", err => {
+    console.trace(err);
+    throw new Error('Couldn\'t get Sortable.js');
+  });
+  console.log(`Building from Gtihub ${gitUsername}/Sortable#${gitBranch}`);
+}
+
+async function proceed(string) {
+  // Get options from source code of Sortblejs
+  const optionsString = /var\s+defaults\s*=\s*{\s*(([^:]+:[^,}]+)+\s*)}/m.exec(string)[1],
+        optionsStringSplit = optionsString.split(''),
+        optionsArray = [];
+  // Read them into an array [ key, value, key, value... ]
+  let current = '',
+      depthLevel = 0,
+      depthExpectColon = false,
+      depthStringOpen = false;
+  for (let i in optionsStringSplit) {
+    const character = optionsStringSplit[i];
+    if (character === '{'
+      || (character === '\'' && !depthStringOpen) || (character === '"' && !depthStringOpen)
+      || character === '?'
+      || character === '(') {
+      depthLevel++;
+      if (character === '?') depthExpectColon = true;
+      if (character === '\'' || character === '"') depthStringOpen = true;
+      if (depthLevel > 0) current += character;
+    } else if (character === '}'
+      || (character === '\'' && depthStringOpen) || (character === '"' && depthStringOpen)
+      || (depthExpectColon && character === ':')
+      || character === ')') {
+      depthLevel--;
+      if (character === ':') depthExpectColon = false;
+      if (character === '\'' || character === '"') depthStringOpen = false;
+      if (depthLevel >= 0) current += character;
+    } else if ((character === ','
+      || character === ':')
+      && depthLevel === 0) {
+      optionsArray.push(current);
+      current = '';
+    } else if (depthLevel > 0 || /[^\s:,]/.test(character)) {
+      current += character;
+    }
+    if (depthLevel < 0) {
+      optionsArray.push(current);
+      break;
+    }
+  }
+  // Throw if read options aren't even
+  if (optionsArray.length % 2) {
+    console.log('Options that were read:', optionsArray);
+    throw new Error('Something went wrong when reading options');
+  }
+  // Process the array to attach types
+  const computedOptions = {};
+  let key, value, type;
+  optionsArray.forEach((item, index) => {
+    index % 2 ? value = item : key = item;
+    if (value && key) {
+      if (!DISABLED_PROPERTIES.includes(key)) {
+        if (value === 'false' || value === 'true') type = 'Boolean'
+        else if (Number(value) !== NaN) type = 'Number'
+        else if (/$\s*\{/.test(value)) type = 'Object'
+        else if (/$\s*\[/.test(value)) type = 'Array'
+        else type = 'String'
+        computedOptions[key] = { value, type };
+      }
+      key = value = type = null;
+    }
+  });
+
+  // Get template file
+  const template = await fs.readFile(path.join(__dirname, 'polymer-sortablejs-template.html'), 'utf8');
+  let generatedTemplate = template;
+
+  // Generate properties
+  generatedTemplate = generatedTemplate.replace(/^(\s*)\/\*properties\*\//m, (_, spacing) => {
+    let output = '';
+    for (key in computedOptions) {
+      const type = computedOptions[key].type,
+            value = computedOptions[key].value;
+      output += `${spacing}${key}: { type: ${type}, value: function() { return ${value} }, observer: '${key}Changed' },\n`
+    }
+    return output.slice(0, -2);
+  });
+
+  // Generate observers
+  generatedTemplate = generatedTemplate.replace(/^(\s*)\/\*propertyobservers\*\//m, (_, spacing) => {
+    let output = '';
+    for (key in computedOptions) {
+      if (!new RegExp(key + 'Changed').test(template))
+        output += `${spacing}${key}Changed: function(value) { this.sortable && this.sortable.option("${key}", value); },\n`
+    }
+    return output.slice(0, -2);
+  });
+
+  await fs.writeFile(path.join(__dirname, 'polymer-sortablejs.html'), generatedTemplate, 'utf8');
+}