From 20219a4f52edea537c5b1e2cea88bd5a3a8f335f Mon Sep 17 00:00:00 2001
From: Hanaasagi <ambiguous404@gmail.com>
Date: Tue, 7 Nov 2023 20:23:33 +0900
Subject: [PATCH] fix(render): precache n-1 and n+1 pages

---
 yazi-core/src/tab/folder.rs | 17 +++++++++++++++--
 yazi-fm/src/app.rs          |  6 ++----
 2 files changed, 17 insertions(+), 6 deletions(-)

diff --git a/yazi-core/src/tab/folder.rs b/yazi-core/src/tab/folder.rs
index 44a356a6..5e654bf8 100644
--- a/yazi-core/src/tab/folder.rs
+++ b/yazi-core/src/tab/folder.rs
@@ -56,8 +56,21 @@ impl Folder {
 			return false;
 		}
 
+		let old = self.page;
 		self.page = new;
+
+		let prev_page = new.saturating_sub(1);
+		let next_page = new.saturating_add(1);
+
+		if prev_page != new && prev_page != old {
+			emit!(Pages(prev_page));
+		}
+
 		emit!(Pages(new));
+
+		if next_page != new && next_page != old {
+			emit!(Pages(next_page));
+		}
 		true
 	}
 
@@ -115,11 +128,11 @@ impl Folder {
 	#[inline]
 	pub fn hovered(&self) -> Option<&File> { self.files.get(self.cursor) }
 
-	pub fn paginate(&self) -> &[File] {
+	pub fn paginate(&self, page: usize) -> &[File] {
 		let len = self.files.len();
 		let limit = MANAGER.layout.folder_height();
 
-		let start = (self.page * limit).min(len.saturating_sub(1));
+		let start = (page * limit).min(len.saturating_sub(1));
 		let end = (start + limit).min(len);
 		&self.files[start..end]
 	}
diff --git a/yazi-fm/src/app.rs b/yazi-fm/src/app.rs
index 3a83a297..40f80ae6 100644
--- a/yazi-fm/src/app.rs
+++ b/yazi-fm/src/app.rs
@@ -143,10 +143,8 @@ impl App {
 				}
 			}
 			Event::Pages(page) => {
-				if manager.current().page == page {
-					let targets = self.cx.manager.current().paginate();
-					tasks.precache_mime(targets, &self.cx.manager.mimetype);
-				}
+				let targets = self.cx.manager.current().paginate(page);
+				tasks.precache_mime(targets, &self.cx.manager.mimetype);
 			}
 			Event::Mimetype(mimes) => {
 				if manager.update_mimetype(mimes, tasks) {