Replace old JavaScript with simpler vanilla version

Pomf's old JavaScript is a frozen dependency hell with an old version of
Zepto. The amount of code included has reached the point of
unmaintainability, where nobody really understands very well how the
code works.

This code gets rid of all the previous client-side JavaScript and
replaces it with new, vanilla JavaScript. No dependencies required. This
new JavaScript should be quite a bit faster too.

Browser backwards compatibility has not been tested yet, however it is
expected that IE10 and later will work, improving our current backwards
compatibility.

Reviewed-by: Eliot Whalan <ewhal@pantsu.cat>
[wub@partyvan.eu: Added Git commit message and fixed Git branching.
Reverted /*   outline-offset: -2px;*/ removal.]
Signed-off-by: Juuso Lapinlampi <wub@partyvan.eu>

1 files changed, 148 insertions, 0 deletions

diff --git a/js/app.js b/js/app.js
new file mode 100644
index 0000000..abb22ed
--- /dev/null
+++ b/js/app.js
@@ -0,0 +1,148 @@
+function addRow(file) {
+  var row = document.createElement('li');
+
+  var name = document.createElement('span');
+  name.textContent = file.name;
+  name.className = 'file-name';
+
+  var progressIndicator = document.createElement('span');
+  progressIndicator.className = 'progress-percent';
+  progressIndicator.textContent = '0%';
+
+  var progressBar = document.createElement('progress');
+  progressBar.className = 'file-progress';
+  progressBar.setAttribute("max", "100");
+  progressBar.setAttribute("value", "0");
+
+  row.appendChild(name);
+  row.appendChild(progressBar);
+  row.appendChild(progressIndicator);
+
+  document.getElementById('upload-filelist').appendChild(row);
+  return row;
+}
+
+function handleUploadProgress(evt) {
+  var xhr = evt.target;
+  var bar = xhr.bar;
+  var percentIndicator = xhr.percent;
+
+  if (evt.lengthComputable) {
+    var progressPercent = Math.floor((evt.loaded / evt.total) * 100);
+    bar.setAttribute("value", progressPercent);
+    percentIndicator.textContent = progressPercent + '%';
+  }
+}
+
+function handleUploadComplete(evt) {
+  var xhr = evt.target;
+  var bar = xhr.bar;
+  var row = xhr.row;
+  var percentIndicator = xhr.percent;
+
+  percentIndicator.style.visibility = "hidden";
+  bar.style.visibility = "hidden";
+  row.removeChild(bar);
+  row.removeChild(percentIndicator);
+  var respStatus = xhr.status;
+
+  var url = document.createElement('span');
+  url.className = 'file-url';
+  row.appendChild(url);
+
+  var link = document.createElement('a');
+  if (respStatus === 200) {
+    var response = JSON.parse(xhr.responseText);
+    if (response.success) {
+      link.textContent = response.files[0].url.replace(/.*?:\/\//g, "");
+      link.href = response.files[0].url;
+      url.appendChild(link);
+    } else {
+      bar.innerHTML = 'Error: ' + response.reason;
+    }
+  } else if (respStatus === 413) {
+    link.textContent = 'File Too big!';
+    url.appendChild(link);
+  } else {
+    link.textContent = 'Server error!';
+    url.appendChild(link);
+  }
+}
+
+function uploadFile(file, row) {
+  var bar = row.querySelector('.file-progress');
+  var percentIndicator = row.querySelector('.progress-percent');
+  var xhr = new XMLHttpRequest();
+  xhr.open('POST', '/upload.php');
+
+  xhr["row"] = row;
+  xhr["bar"] = bar;
+  xhr["percent"] = percentIndicator;
+  xhr.upload["bar"] = bar;
+  xhr.upload["percent"] = percentIndicator;
+
+  xhr.addEventListener('load', handleUploadComplete, false);
+  xhr.upload.onprogress = handleUploadProgress;
+
+  var form = new FormData();
+  form.append('files[]', file);
+  xhr.send(form);
+}
+
+function stopDefaultEvent(evt) {
+  evt.stopPropagation();
+  evt.preventDefault();
+}
+
+function handleDrag(state, element, evt) {
+  stopDefaultEvent(evt);
+  if (state.dragCount == 1) {
+    element.textContent = "Drop it here~";
+  }
+  state.dragCount += 1;
+}
+
+function handleDragAway(state, element, evt) {
+  stopDefaultEvent(evt);
+  state.dragCount -= 1;
+  if (state.dragCount == 0) {
+    element.textContent = "Select or drop file(s)";
+  }
+}
+
+function handleDragDrop(state, element, evt) {
+  stopDefaultEvent(evt);
+  handleDragAway(state, element, evt);
+  var len = evt.dataTransfer.files.length;
+  for (var i = 0; i < len; i++) {
+    var file = evt.dataTransfer.files[i];
+    var row = addRow(file);
+    uploadFile(file, row);
+  }
+}
+
+function uploadFiles(evt) {
+  var len = evt.target.files.length;
+  for (var i = 0; i < len; i++) {
+    var file = evt.target.files[i];
+    var row = addRow(file);
+    uploadFile(file, row);
+  }
+}
+
+function selectFiles(target, evt) {
+  stopDefaultEvent(evt);
+  target.click();
+}
+
+var state = { dragCount: 0 };
+var uploadButton = document.getElementById('upload-btn');
+window.addEventListener('dragenter', handleDrag.bind(this, state, uploadButton), false);
+window.addEventListener('dragleave', handleDragAway.bind(this, state, uploadButton), false);
+window.addEventListener('drop', handleDragAway.bind(this, state, uploadButton), false);
+window.addEventListener('dragover', stopDefaultEvent, false);
+
+var uploadInput = document.getElementById('upload-input');
+uploadInput.addEventListener('change', uploadFiles);
+uploadButton.addEventListener('click', selectFiles.bind(this, uploadInput));
+uploadButton.addEventListener('drop', handleDragDrop.bind(this, state, uploadButton), false);