move messages to content

1 files changed, 27 insertions, 0 deletions

diff --git a/src/pages/completion.js b/src/pages/completion.js
new file mode 100644
index 0000000..4c69afb
--- /dev/null
+++ b/src/pages/completion.js
@@ -0,0 +1,27 @@
+export default class Completion {
+  constructor(completions) {
+    if (typeof completions.length !== 'number') {
+      throw new TypeError('completions does not have a length in number');
+    }
+    this.completions = completions;
+    this.index = 0;
+  }
+
+  prev() {
+    let length = this.completions.length;
+    if (length === 0) {
+      return null;
+    }
+    this.index = (this.index + length - 1) % length;
+    return this.completions[this.index];
+  }
+
+  next() {
+    if (this.completions.length === 0) {
+      return null;
+    }
+    let item = this.completions[this.index];
+    this.index = (this.index + 1) % this.completions.length;
+    return item;
+  }
+}