1 files changed, 65 insertions, 0 deletions
diff --git a/src/state/models/ui/reminders.ts b/src/state/models/ui/reminders.ts
new file mode 100644
index 000000000..f8becdec3
--- /dev/null
+++ b/src/state/models/ui/reminders.ts
@@ -0,0 +1,65 @@
+import {makeAutoObservable} from 'mobx'
+import {isObj, hasProp} from 'lib/type-guards'
+import {RootStoreModel} from '../root-store'
+import {toHashCode} from 'lib/strings/helpers'
+
+const DAY = 60e3 * 24 * 1 // 1 day (ms)
+
+export class Reminders {
+  // NOTE
+  // by defaulting to the current date, we ensure that the user won't be nagged
+  // on first run (aka right after creating an account)
+  // -prf
+  lastEmailConfirm: Date = new Date()
+
+  constructor(public rootStore: RootStoreModel) {
+    makeAutoObservable(
+      this,
+      {serialize: false, hydrate: false},
+      {autoBind: true},
+    )
+  }
+
+  serialize() {
+    return {
+      lastEmailConfirm: this.lastEmailConfirm
+        ? this.lastEmailConfirm.toISOString()
+        : undefined,
+    }
+  }
+
+  hydrate(v: unknown) {
+    if (
+      isObj(v) &&
+      hasProp(v, 'lastEmailConfirm') &&
+      typeof v.lastEmailConfirm === 'string'
+    ) {
+      this.lastEmailConfirm = new Date(v.lastEmailConfirm)
+    }
+  }
+
+  get shouldRequestEmailConfirmation() {
+    const sess = this.rootStore.session.currentSession
+    if (!sess) {
+      return false
+    }
+    if (sess.emailConfirmed) {
+      return false
+    }
+    const today = new Date()
+    // shard the users into 2 day of the week buckets
+    // (this is to avoid a sudden influx of email updates when
+    // this feature rolls out)
+    const code = toHashCode(sess.did) % 7
+    if (code !== today.getDay() && code !== (today.getDay() + 1) % 7) {
+      return false
+    }
+    // only ask once a day at most, but because of the bucketing
+    // this will be more like weekly
+    return Number(today) - Number(this.lastEmailConfirm) > DAY
+  }
+
+  setEmailConfirmationRequested() {
+    this.lastEmailConfirm = new Date()
+  }
+}