From 7acde1c1747459515a377ca8742bef70abf9b5ab Mon Sep 17 00:00:00 2001
From: Andrew Bastin <andrewbastin.k@gmail.com>
Date: Sun, 15 Aug 2021 10:45:26 +0530
Subject: [PATCH] feat: rest request sync with firestore

---
 helpers/fb/auth.ts    | 36 ++++++++++++++++++-
 helpers/fb/request.ts | 83 +++++++++++++++++++++++++++++++++++++++++++
 pages/index.vue       | 27 ++++++++++++++
 3 files changed, 145 insertions(+), 1 deletion(-)
 create mode 100644 helpers/fb/request.ts

diff --git a/helpers/fb/auth.ts b/helpers/fb/auth.ts
index 6851d2dea..de51c5f36 100644
--- a/helpers/fb/auth.ts
+++ b/helpers/fb/auth.ts
@@ -1,7 +1,15 @@
 import firebase from "firebase/app"
 import "firebase/firestore"
 import "firebase/auth"
-import { BehaviorSubject, Subject } from "rxjs"
+import {
+  BehaviorSubject,
+  distinctUntilChanged,
+  filter,
+  map,
+  Subject,
+  Subscription,
+} from "rxjs"
+import { onBeforeUnmount, onMounted } from "@nuxtjs/composition-api"
 
 export type HoppUser = firebase.User & {
   provider?: string
@@ -219,3 +227,29 @@ export async function setProviderInfo(id: string, token: string) {
     throw e
   }
 }
+
+/**
+ * A Vue composable function that is called when the auth status
+ * is being updated to being logged in (fired multiple times),
+ * this is also called on component mount if the login
+ * was already resolved before mount.
+ */
+export function onLoggedIn(exec: (user: HoppUser) => void) {
+  let sub: Subscription | null = null
+
+  onMounted(() => {
+    sub = currentUser$
+      .pipe(
+        map((user) => !!user), // Get a logged in status (true or false)
+        distinctUntilChanged(), // Don't propagate unless the status updates
+        filter((x) => x) // Don't propagate unless it is logged in
+      )
+      .subscribe(() => {
+        exec(currentUser$.value!)
+      })
+  })
+
+  onBeforeUnmount(() => {
+    sub?.unsubscribe()
+  })
+}
diff --git a/helpers/fb/request.ts b/helpers/fb/request.ts
new file mode 100644
index 000000000..f56996e8a
--- /dev/null
+++ b/helpers/fb/request.ts
@@ -0,0 +1,83 @@
+import firebase from "firebase/app"
+import "firebase/firestore"
+import {
+  audit,
+  combineLatest,
+  distinctUntilChanged,
+  EMPTY,
+  from,
+  map,
+  Subscription,
+} from "rxjs"
+import {
+  HoppRESTRequest,
+  translateToNewRequest,
+} from "../types/HoppRESTRequest"
+import { currentUser$, HoppUser } from "./auth"
+import { restRequest$ } from "~/newstore/RESTSession"
+
+/**
+ * Writes a request to a user's firestore sync
+ *
+ * @param user The user to write to
+ * @param request The request to write to the request sync
+ */
+function writeCurrentRequest(user: HoppUser, request: HoppRESTRequest) {
+  return firebase
+    .firestore()
+    .collection("users")
+    .doc(user.uid)
+    .collection("requests")
+    .doc("rest")
+    .set(request)
+}
+
+/**
+ * Loads the synced request from the firestore sync
+ *
+ * @returns Fetched request object if exists else null
+ */
+export async function loadRequestFromSync(): Promise<HoppRESTRequest | null> {
+  const currentUser = currentUser$.value
+
+  if (!currentUser)
+    throw new Error("Cannot load request from sync without login")
+
+  const doc = await firebase
+    .firestore()
+    .collection("users")
+    .doc(currentUser.uid)
+    .collection("requests")
+    .doc("rest")
+    .get()
+
+  const data = doc.data()
+
+  if (!data) return null
+  else return translateToNewRequest(data)
+}
+
+/**
+ * Performs sync of the REST Request session with Firestore.
+ *
+ * @returns A subscription to the sync observable stream.
+ * Unsubscribe to stop syncing.
+ */
+export function startRequestSync(): Subscription {
+  const sub = combineLatest([
+    currentUser$,
+    restRequest$.pipe(distinctUntilChanged()),
+  ])
+    .pipe(
+      map(([user, request]) =>
+        user ? from(writeCurrentRequest(user, request)) : EMPTY
+      ),
+      audit((x) => x)
+    )
+    .subscribe(() => {
+      // NOTE: This subscription should be kept
+      console.log("synced request")
+    })
+
+  return sub
+}
diff --git a/pages/index.vue b/pages/index.vue
index 9f44dd8c8..13dead1f6 100644
--- a/pages/index.vue
+++ b/pages/index.vue
@@ -77,6 +77,7 @@
 import {
   computed,
   defineComponent,
+  onBeforeUnmount,
   onMounted,
   useContext,
   watch,
@@ -84,6 +85,7 @@ import {
 import { Splitpanes, Pane } from "splitpanes"
 import "splitpanes/dist/splitpanes.css"
 import { map } from "rxjs/operators"
+import { Subscription } from "rxjs"
 import { useSetting } from "~/newstore/settings"
 import {
   restRequest$,
@@ -101,6 +103,8 @@ import {
   useStream,
   useStreamSubscriber,
 } from "~/helpers/utils/composables"
+import { loadRequestFromSync, startRequestSync } from "~/helpers/fb/request"
+import { onLoggedIn } from "~/helpers/fb/auth"
 
 function bindRequestToURLParams() {
   const {
@@ -159,11 +163,34 @@ function bindRequestToURLParams() {
   })
 }
 
+function setupRequestSync() {
+  const { route } = useContext()
+
+  // Subscription to request sync
+  let sub: Subscription | null = null
+
+  // Load request on login resolve and start sync
+  onLoggedIn(async () => {
+    if (Object.keys(route.value.query).length === 0) {
+      const request = await loadRequestFromSync()
+      if (request) setRESTRequest(request)
+    }
+
+    sub = startRequestSync()
+  })
+
+  // Stop subscripton to stop syncing
+  onBeforeUnmount(() => {
+    sub?.unsubscribe()
+  })
+}
+
 export default defineComponent({
   components: { Splitpanes, Pane },
   setup() {
     const { subscribeToStream } = useStreamSubscriber()
 
+    setupRequestSync()
     bindRequestToURLParams()
 
     subscribeToStream(restRequest$, (x) => {