From ac156034d154ed99b6a975bc702abf14f120fa81 Mon Sep 17 00:00:00 2001
From: patak <matias.capeletto@gmail.com>
Date: Tue, 22 Nov 2022 14:03:36 +0100
Subject: [PATCH] feat: global relationships batching (#24)

---
 components/account/AccountCard.vue            | 16 ++++-----
 components/account/AccountHeader.vue          | 18 +++-------
 .../account/AccountPaginator.client.vue       | 14 --------
 components/common/CommonPaginator.vue         |  9 +----
 composables/masto.ts                          | 36 ++++++++++++++++++-
 5 files changed, 47 insertions(+), 46 deletions(-)

diff --git a/components/account/AccountCard.vue b/components/account/AccountCard.vue
index f3d2e54c..64995ecf 100644
--- a/components/account/AccountCard.vue
+++ b/components/account/AccountCard.vue
@@ -1,25 +1,21 @@
 <script setup lang="ts">
 import type { Account } from 'masto'
 
-const { account, following } = defineProps<{
+const { account } = defineProps<{
   account: Account
-  following?: boolean
 }>()
 
 const masto = await useMasto()
 
-let isFollowing = $ref<boolean | undefined>(following)
-watch($$(following), () => {
-  isFollowing = following
-})
+const relationship = $(useRelationship(account))
 
 function unfollow() {
   masto.accounts.unfollow(account.id)
-  isFollowing = false
+  relationship!.following = false
 }
 function follow() {
   masto.accounts.follow(account.id)
-  isFollowing = true
+  relationship!.following = true
 }
 </script>
 
@@ -27,8 +23,8 @@ function follow() {
   <div flex justify-between>
     <AccountInfo :account="account" p3 />
     <div h-full p5>
-      <div v-if="isFollowing === true" color-purple hover:color-gray hover:cursor-pointer i-ri:user-unfollow-fill @click="unfollow" />
-      <div v-else-if="isFollowing === false" color-gray hover:color-purple hover:cursor-pointer i-ri:user-follow-fill @click="follow" />
+      <div v-if="relationship?.following === true" color-purple hover:color-gray hover:cursor-pointer i-ri:user-unfollow-fill @click="unfollow" />
+      <div v-else-if="relationship?.following === false" color-gray hover:color-purple hover:cursor-pointer i-ri:user-follow-fill @click="follow" />
     </div>
   </div>
 </template>
diff --git a/components/account/AccountHeader.vue b/components/account/AccountHeader.vue
index 9263c86e..bd0732ad 100644
--- a/components/account/AccountHeader.vue
+++ b/components/account/AccountHeader.vue
@@ -5,22 +5,14 @@ const { account } = defineProps<{
   account: Account
 }>()
 
-let isFollowing = $ref<boolean | undefined>()
-let isFollowedBy = $ref<boolean | undefined>()
+const relationship = $(useRelationship(account))
 
 let masto: MastoClient
 
-onMounted(async () => {
-  masto ??= await useMasto()
-  const relationship = (await masto.accounts.fetchRelationships([account.id]))[0]
-  isFollowing = relationship.following
-  isFollowedBy = relationship.followedBy
-})
-
 async function toggleFollow() {
-  isFollowing = !isFollowing
+  relationship!.following = !relationship!.following
   masto ??= await useMasto()
-  await masto.accounts[isFollowing ? 'follow' : 'unfollow'](account.id)
+  await masto.accounts[relationship!.following ? 'follow' : 'unfollow'](account.id)
 }
 
 const createdAt = $computed(() => {
@@ -50,9 +42,9 @@ const createdAt = $computed(() => {
           </NuxtLink>
         </div>
         <div flex gap-2>
-          <button flex gap-1 items-center w-full rounded op75 hover="op100 text-white b-purple" group @click="toggleFollow">
+          <button v-if="relationship" flex gap-1 items-center w-full rounded op75 hover="op100 text-white b-purple" group @click="toggleFollow">
             <div rounded w-30 p2 group-hover="bg-rose/10">
-              {{ isFollowing ? 'Unfollow' : isFollowedBy ? 'Follow back' : 'Follow' }}
+              {{ relationship?.following ? 'Unfollow' : relationship?.followedBy ? 'Follow back' : 'Follow' }}
             </div>
           </button>
           <!-- <button flex gap-1 items-center w-full rounded op75 hover="op100 text-purple" group>
diff --git a/components/account/AccountPaginator.client.vue b/components/account/AccountPaginator.client.vue
index 14389294..0e75d1d5 100644
--- a/components/account/AccountPaginator.client.vue
+++ b/components/account/AccountPaginator.client.vue
@@ -4,30 +4,16 @@ import type { Account, Paginator } from 'masto'
 const { paginator } = defineProps<{
   paginator: Paginator<any, Account[]>
 }>()
-
-const masto = await useMasto()
-
-const metadataMap = $ref<{ [key: string]: { following?: boolean } }>({})
-async function onNewItems(items: Account[]) {
-  for (const item of items)
-    metadataMap[item.id] = { following: undefined }
-
-  const relationships = await masto.accounts.fetchRelationships(items.map(item => item.id))
-  for (const rel of relationships)
-    metadataMap[rel.id].following = rel.following
-}
 </script>
 
 <template>
   <CommonPaginator
     :paginator="paginator"
     border="t border"
-    @items="onNewItems"
   >
     <template #default="{ item }">
       <AccountCard
         :account="item"
-        :following="metadataMap[item.id]?.following"
         border="b border" py-1
       />
     </template>
diff --git a/components/common/CommonPaginator.vue b/components/common/CommonPaginator.vue
index d7e14244..4b199d34 100644
--- a/components/common/CommonPaginator.vue
+++ b/components/common/CommonPaginator.vue
@@ -1,5 +1,4 @@
 <script setup lang="ts">
-import type { Ref } from 'vue'
 import type { Paginator } from 'masto'
 
 const { paginator, keyProp = 'id' } = defineProps<{
@@ -7,13 +6,7 @@ const { paginator, keyProp = 'id' } = defineProps<{
   keyProp?: string
 }>()
 
-const emit = defineEmits(['items'])
-
-const { items, newItems, state, endAnchor, error } = usePaginator(paginator)
-
-watch(newItems, () => {
-  emit('items', newItems.value)
-})
+const { items, state, endAnchor, error } = usePaginator(paginator)
 </script>
 
 <template>
diff --git a/composables/masto.ts b/composables/masto.ts
index d01f4872..4a7c9f48 100644
--- a/composables/masto.ts
+++ b/composables/masto.ts
@@ -1,5 +1,39 @@
-import type { Account } from 'masto'
+import type { Ref } from 'vue'
+import type { Account, MastoClient, Relationship } from 'masto'
 
 export function getDisplayName(account: Account) {
   return account.displayName || account.username
 }
+
+// Batch requests for relationships when used in the UI
+// We don't want to hold to old values, so every time a Relationship is needed it
+// is requested again from the server to show the latest state
+
+const requestedRelationships = new Map<string, Ref<Relationship | undefined> >()
+let timeoutHandle: NodeJS.Timeout | undefined
+
+export function useRelationship(account: Account): Ref<Relationship | undefined> {
+  let relationship = requestedRelationships.get(account.id)
+  if (relationship)
+    return relationship
+  relationship = ref<Relationship | undefined>()
+  requestedRelationships.set(account.id, relationship)
+  if (timeoutHandle)
+    clearTimeout(timeoutHandle)
+  timeoutHandle = setTimeout(() => {
+    timeoutHandle = undefined
+    fetchRelationships()
+  }, 100)
+  return relationship
+}
+
+async function fetchRelationships() {
+  const masto = await useMasto()
+
+  const requested = Array.from(requestedRelationships.entries())
+  requestedRelationships.clear()
+
+  const relationships = await masto.accounts.fetchRelationships(requested.map(([id]) => id))
+  for (let i = 0; i < requested.length; i++)
+    requested[i][1].value = relationships[i]
+}