select next/previous unread feed/category when marking all as read (#1558)

commafeed-client/src/app/tree/thunks.ts

@@ -1,8 +1,9 @@
 import { createAppAsyncThunk } from "app/async-thunk"
 import { client } from "app/client"
+import { redirectToCategory, redirectToFeed } from "app/redirect/thunks"
 import { incrementUnreadCount } from "app/tree/slice"
-import type { CollapseRequest } from "app/types"
-import { flattenCategoryTree } from "app/utils"
+import type { CollapseRequest, Subscription } from "app/types"
+import { flattenCategoryTree, visitCategoryTree } from "app/utils"
 
 export const reloadTree = createAppAsyncThunk("tree/reload", async () => await client.category.getRoot().then(r => r.data))
 
@@ -11,6 +12,72 @@ export const collapseTreeCategory = createAppAsyncThunk(
     async (req: CollapseRequest) => await client.category.collapse(req)
 )
 
+export const selectNextUnreadTreeItem = createAppAsyncThunk("tree/selectNextUnreadItem", (_, thunkApi) => {
+    const state = thunkApi.getState()
+    const root = state.tree.rootCategory
+    if (!root) return
+
+    const { source } = state.entries
+    if (source.type === "category") {
+        const categories = flattenCategoryTree(root)
+        const index = categories.findIndex(c => c.id === source.id)
+        if (index === -1) return
+
+        for (let i = index + 1; i < categories.length; i++) {
+            const c = categories[i]
+            if (c.feeds.some(f => f.unread > 0)) {
+                return thunkApi.dispatch(redirectToCategory(String(c.id)))
+            }
+        }
+    } else if (source.type === "feed") {
+        const feeds: Subscription[] = []
+        visitCategoryTree(root, c => feeds.push(...c.feeds), { childrenFirst: true })
+
+        const index = feeds.findIndex(f => f.id === +source.id)
+        if (index === -1) return
+
+        for (let i = index + 1; i < feeds.length; i++) {
+            const f = feeds[i]
+            if (f.unread > 0) {
+                return thunkApi.dispatch(redirectToFeed(String(f.id)))
+            }
+        }
+    }
+})
+
+export const selectPreviousUnreadTreeItem = createAppAsyncThunk("tree/selectPreviousUnreadItem", (_, thunkApi) => {
+    const state = thunkApi.getState()
+    const root = state.tree.rootCategory
+    if (!root) return
+
+    const { source } = state.entries
+    if (source.type === "category") {
+        const categories = flattenCategoryTree(root)
+        const index = categories.findIndex(c => c.id === source.id)
+        if (index === -1) return
+
+        for (let i = index - 1; i >= 0; i--) {
+            const c = categories[i]
+            if (c.feeds.some(f => f.unread > 0)) {
+                return thunkApi.dispatch(redirectToCategory(String(c.id)))
+            }
+        }
+    } else if (source.type === "feed") {
+        const feeds: Subscription[] = []
+        visitCategoryTree(root, c => feeds.push(...c.feeds), { childrenFirst: true })
+
+        const index = feeds.findIndex(f => f.id === +source.id)
+        if (index === -1) return
+
+        for (let i = index - 1; i >= 0; i--) {
+            const f = feeds[i]
+            if (f.unread > 0) {
+                return thunkApi.dispatch(redirectToFeed(String(f.id)))
+            }
+        }
+    }
+})
+
 export const newFeedEntriesDiscovered = createAppAsyncThunk(
     "tree/new-feed-entries-discovered",
     async ({ feedId, amount }: { feedId: number; amount: number }, thunkApi) => {