hall demo

1 files changed, 41 insertions, 0 deletions

diff --git a/client/lib/keys.js b/client/lib/keys.js
new file mode 100644
index 0000000..5b98ace
--- /dev/null
+++ b/client/lib/keys.js
@@ -0,0 +1,41 @@
+const keys = {}
+const key_numbers = {}
+const letters = "yxcvbnmasdfghjklqwertuiopz"
+const numbers = "1234567890"
+
+let callback = function(){}
+
+letters.toUpperCase().split("").map(function(k,i){
+  keys[k.charCodeAt(0)] = i
+})
+
+keys['Z'.charCodeAt(0)] = 0
+
+numbers.split("").map(function(k,i){
+  keys[k.charCodeAt(0)] = i+letters.length
+  key_numbers[k.charCodeAt(0)] = true
+})
+
+window.addEventListener("keydown", keydown, true)
+function keydown (e) {
+  if (e.altKey || e.ctrlKey || e.metaKey) {
+    e.stopPropagation()
+    return
+  }
+  if (document.activeElement instanceof HTMLInputElement &&
+      (e.keyCode in key_numbers)) {
+    e.stopPropagation()
+    return
+  }
+  if (! (e.keyCode in keys)) return
+  var index = keys[e.keyCode]
+  if (e.shiftKey) index += letters.length
+  index -= 7
+  callback(index)
+}
+
+function listen (fn) {
+  callback = fn
+}
+
+export default { listen }
\ No newline at end of file