From 7f30231485a58504710d63dcd0bf323bb3ea5e89 Mon Sep 17 00:00:00 2001
From: yw1ee <151739702+yw1ee@users.noreply.github.com>
Date: Wed, 30 Oct 2024 13:26:53 +0900
Subject: [PATCH] feat: prioritize paths that need to be processed first during
 bulk renaming (#1801)

Co-authored-by: sxyazi <sxyazi@gmail.com>
---
 yazi-core/src/manager/commands/bulk_rename.rs | 88 ++++++++++++++++++-
 1 file changed, 87 insertions(+), 1 deletion(-)

diff --git a/yazi-core/src/manager/commands/bulk_rename.rs b/yazi-core/src/manager/commands/bulk_rename.rs
index 88bf79d2c..17bda7571 100644
--- a/yazi-core/src/manager/commands/bulk_rename.rs
+++ b/yazi-core/src/manager/commands/bulk_rename.rs
@@ -53,7 +53,7 @@ impl Manager {
 			return Ok(());
 		}
 
-		let todo: Vec<_> = old.into_iter().zip(new).filter(|(o, n)| o != n).collect();
+		let todo = Self::prioritized_paths(old, new);
 		if todo.is_empty() {
 			return Ok(());
 		}
@@ -117,4 +117,90 @@ impl Manager {
 		stdin().read_exact(&mut [0]).await?;
 		Ok(())
 	}
+
+	fn prioritized_paths(old: Vec<PathBuf>, new: Vec<PathBuf>) -> Vec<(PathBuf, PathBuf)> {
+		let orders: HashMap<_, _> = old.iter().enumerate().map(|(i, p)| (p, i)).collect();
+		let mut incomes: HashMap<_, _> = old.iter().map(|p| (p, false)).collect();
+		let mut todos: HashMap<_, _> = old
+			.iter()
+			.zip(new)
+			.map(|(o, n)| {
+				incomes.get_mut(&n).map(|b| *b = true);
+				(o, n)
+			})
+			.collect();
+
+		let mut sorted = Vec::with_capacity(old.len());
+		while !todos.is_empty() {
+			// Paths that are non-incomes and don't need to be prioritized in this round
+			let mut outcomes: Vec<_> = incomes.iter().filter(|(_, &b)| !b).map(|(&p, _)| p).collect();
+			outcomes.sort_unstable_by(|a, b| orders[b].cmp(&orders[a]));
+
+			// If there're no outcomes, it means there are cycles in the renaming
+			if outcomes.is_empty() {
+				let mut remain: Vec<_> = todos.into_iter().map(|(o, n)| (o.clone(), n)).collect();
+				remain.sort_unstable_by(|(a, _), (b, _)| orders[a].cmp(&orders[b]));
+				sorted.reverse();
+				sorted.extend(remain);
+				return sorted;
+			}
+
+			for old in outcomes {
+				let Some(new) = todos.remove(old) else { unreachable!() };
+				incomes.remove(&old);
+				incomes.get_mut(&new).map(|b| *b = false);
+				sorted.push((old.clone(), new));
+			}
+		}
+		sorted.reverse();
+		sorted
+	}
+}
+
+#[cfg(test)]
+mod tests {
+	use super::*;
+
+	#[test]
+	fn test_sort() {
+		fn cmp(input: &[(&str, &str)], expected: &[(&str, &str)]) {
+			let sorted = Manager::prioritized_paths(
+				input.iter().map(|&(o, _)| o.into()).collect(),
+				input.iter().map(|&(_, n)| n.into()).collect(),
+			);
+			let sorted: Vec<_> =
+				sorted.iter().map(|(o, n)| (o.to_str().unwrap(), n.to_str().unwrap())).collect();
+			assert_eq!(sorted, expected);
+		}
+
+		#[rustfmt::skip]
+		cmp(
+			&[("2", "3"), ("1", "2"), ("3", "4")],
+			&[("3", "4"), ("2", "3"), ("1", "2")]
+		);
+
+		#[rustfmt::skip]
+		cmp(
+			&[("1", "3"), ("2", "3"), ("3", "4")],
+			&[("3", "4"), ("1", "3"), ("2", "3")]
+		);
+
+		#[rustfmt::skip]
+		cmp(
+			&[("2", "1"), ("1", "2")],
+			&[("2", "1"), ("1", "2")]
+		);
+
+		#[rustfmt::skip]
+		cmp(
+			&[("3", "2"), ("2", "1"), ("1", "3"), ("a", "b"), ("b", "c")],
+			&[("b", "c"), ("a", "b"), ("3", "2"), ("2", "1"), ("1", "3")]
+		);
+
+		#[rustfmt::skip]
+		cmp(
+			&[("b", "b_"), ("a", "a_"), ("c", "c_")],
+			&[("b", "b_"), ("a", "a_"), ("c", "c_")],
+		);
+	}
 }