Task 72: add CSV AppMessage backup

1 files changed, 45 insertions, 0 deletions

diff --git a/src/pkjs/index.js b/src/pkjs/index.js
new file mode 100644
index 0000000..bc8777e
--- /dev/null
+++ b/src/pkjs/index.js
@@ -0,0 +1,45 @@
+var Keys = require('message_keys');
+
+var CSV_STORAGE_KEY = 'fastforge.backup.csv';
+var CSV_UPDATED_AT_KEY = 'fastforge.backup.csv.updated_at';
+
+function ensureArraySize(rows, total) {
+  if (!rows || rows.length !== total) {
+    return new Array(total);
+  }
+  return rows;
+}
+
+function storeCsv(rows) {
+  var csv = rows.join('\n');
+  localStorage.setItem(CSV_STORAGE_KEY, csv);
+  localStorage.setItem(CSV_UPDATED_AT_KEY, new Date().toISOString());
+  console.log('FastForge backup stored, bytes=' + csv.length);
+}
+
+function onAppMessage(event) {
+  var payload = event.payload || {};
+  var sequence = payload[Keys.EXPORT_SEQUENCE];
+  var total = payload[Keys.EXPORT_TOTAL];
+  var row = payload[Keys.EXPORT_ROW];
+
+  if (typeof sequence !== 'number' || typeof total !== 'number' || typeof row !== 'string') {
+    console.log('FastForge backup chunk missing fields: ' + JSON.stringify(payload));
+    return;
+  }
+
+  var rows = ensureArraySize(onAppMessage.rows, total);
+  rows[sequence] = row;
+  onAppMessage.rows = rows;
+
+  if (sequence + 1 === total) {
+    storeCsv(rows);
+    onAppMessage.rows = null;
+  }
+}
+
+Pebble.addEventListener('ready', function() {
+  console.log('FastForge companion ready');
+});
+
+Pebble.addEventListener('appmessage', onAppMessage);