1 files changed, 89 insertions, 0 deletions
diff --git a/models/watchable.js b/models/watchable.js
new file mode 100644
index 00000000..6821f847
--- /dev/null
+++ b/models/watchable.js
@@ -0,0 +1,89 @@
+// simple version, only toggle watch / unwatch
+const simpleWatchable = (collection) => {
+  collection.attachSchema({
+    watchers: {
+      type: [String],
+      optional: true,
+    },
+  });
+
+  collection.helpers({
+    getWatchLevels() {
+      return [true, false];
+    },
+
+    watcherIndex(userId) {
+      return this.watchers.indexOf(userId);
+    },
+
+    findWatcher(userId) {
+      return _.contains(this.watchers, userId);
+    },
+  });
+
+  collection.mutations({
+    setWatcher(userId, level) {
+      // if level undefined or null or false, then remove
+      if (!level) return { $pull: { watchers: userId }};
+      return { $addToSet: { watchers: userId }};
+    },
+  });
+};
+
+// more complex version of same interface, with 3 watching levels
+const complexWatchOptions = ['watching', 'tracking', 'muted'];
+const complexWatchDefault = 'muted';
+
+const complexWatchable = (collection) => {
+  collection.attachSchema({
+    'watchers.$.userId': {
+      type: String,
+    },
+    'watchers.$.level': {
+      type: String,
+      allowedValues: complexWatchOptions,
+    },
+  });
+
+  collection.helpers({
+    getWatchOptions() {
+      return complexWatchOptions;
+    },
+
+    getWatchDefault() {
+      return complexWatchDefault;
+    },
+
+    watcherIndex(userId) {
+      return _.pluck(this.watchers, 'userId').indexOf(userId);
+    },
+
+    findWatcher(userId) {
+      return _.findWhere(this.watchers, { userId });
+    },
+
+    getWatchLevel(userId) {
+      const watcher = this.findWatcher(userId);
+      return watcher ? watcher.level : complexWatchDefault;
+    },
+  });
+
+  collection.mutations({
+    setWatcher(userId, level) {
+      // if level undefined or null or false, then remove
+      if (level === complexWatchDefault) level = null;
+      if (!level) return { $pull: { watchers: { userId }}};
+      const index = this.watcherIndex(userId);
+      if (index<0) return { $push: { watchers: { userId, level }}};
+      return {
+        $set: {
+          [`watchers.${index}.level`]: level,
+        },
+      };
+    },
+  });
+};
+
+complexWatchable(Boards);
+simpleWatchable(Lists);
+simpleWatchable(Cards);