Generate Posts.sketchplugin

// (cmd alt p)

var app = NSApplication.sharedApplication();

if (selection.count() == 0) {
  app.displayDialog_withTitle("You'll need to select a group of layers that makes up your post.", "No Group Selected");
}
else {
  var persistent = NSThread.mainThread().threadDictionary();

  var jsonURL = doc.askForUserInput_initialValue("Where has the JSON gone!?", persistent["jsonURL"] || "");
  var res = httpGET(jsonURL);
  var json = JSON.parse(NSString.alloc().initWithData_encoding(res, NSUTF8StringEncoding));

  if (json) {
    // Store the jsonURL in case you want to use it again.
    persistent["jsonURL"] = jsonURL;

    var items = json.rss.channel.item;
    var numOfPosts = doc.askForUserInput_initialValue("How many posts do you want?", persistent["numOfPosts"] || "");
    persistent["numOfPosts"] = numOfPosts;

    doc.showMessage("Generating " + numOfPosts + " posts...");

    for (var i = 0; i < numOfPosts; i += 1) {
      var item = items[Math.floor(Math.random() * (items.length - 0 + 1))];
      generatePost(selection[0].duplicate(), item, numOfPosts - i);
    }
  }
  else {
    app.displayDialog_withTitle("You'll need to provide a URL to value JSON.", "No JSON Found");
  }
}

function generatePost (post, data, postNumber) {
  // These are used for custom layer processing
  var customProcessors = {
    "pubDate": function (str) {
      return formatDateStr(str);
    },

    "image": function (imgGroup) {
      var imgLayers = imgGroup.layers();
      addPlaceholderImgToGroup(imgGroup);
    },

    "description": function (str) {
      return sanitizeText(str);
    }
  }

  post.setName("post " + (postNumber + 1));

  // Position the post after the previous
  var postHeight = post.frame().height();
  post.frame().addY(postHeight * postNumber);

  var layers = post.layers();


  for (var i = 0; i < layers.count(); i += 1) {
    var curLayer = layers.objectAtIndex(i);
    var key = curLayer.name();
    var strValue = null;

    if (key == 'image') {
      customProcessors["image"](curLayer);
    }

    if (data[key]) {
      strValue = data[key];

      if (customProcessors[key]) {
        strValue = customProcessors[key](data[key]);
      }

      if (curLayer.className() == 'MSTextLayer') {
        curLayer.setStringValue(strValue);
      }
    }
  }
}

// Request an image from the placeholder service lorempixel.com and add it
// to the given group.
function addPlaceholderImgToGroup (group) {
  // The topic of the image placeholder
  var topics = ['animals', 'city', 'food', 'nature'];
  var randTopic = topics[Math.floor(Math.random() * (topics.length - 0 + 1))];

  // We're going to get an image that is the width/height of the mask, plus
  // some extra, that I'm setting arbitrarily.
  var mask = group.layers().objectAtIndex(0);
  group.removeLayer(group.layers().objectAtIndex(1));
  var extraImgSize = 20;
  var imgWidth = mask.frame().width() + extraImgSize;
  var imgHeight = mask.frame().height() + extraImgSize;
  var res = httpGET("http://lorempixel.com/" + imgWidth + "/" + imgHeight + "/" + randTopic);
  var img = NSImage.alloc().initWithData(res);

  var imgLayerName = 'image';
  var imageCollection = group.documentData().images();
  var imageData = imageCollection.addImage_name_convertColourspace(img, imgLayerName, false);
  var newImage = MSBitmapLayer.alloc().initWithImage_parentFrame_name(imageData, group.frame(), imgLayerName);
  group.addLayer(newImage);
}

function formatDateStr (str) {
  var d = new Date(str);

  // I pulled some of this from moment.js. They smrt
  var days = "Sunday_Monday_Tuesday_Wednesday_Thursday_Friday_Saturday".split("_");
  var daysShort = "Sun_Mon_Tue_Wed_Thu_Fri_Sat".split("_");
  var months = "January_February_March_April_May_June_July_August_September_October_November_December".split("_");
  var monthsShort = "Jan_Feb_Mar_Apr_May_Jun_Jul_Aug_Sep_Oct_Nov_Dec".split("_");
  var formatted = daysShort[d.getDay()] + '. ' + months[d.getMonth()] + ' ' + d.getDate() + ', ' + d.getFullYear();

  return formatted;
}

// Quick and dirty html removal
function sanitizeText (str) {
  return str.replace(/<\/?[^>]+(>|$)/g, "");
}

function httpGET (url) {
  var request = NSURLRequest.requestWithURL(NSURL.URLWithString(url));
  var response = NSURLConnection.sendSynchronousRequest_returningResponse_error(request, null, null);
  return response;
}