From 11e408cc17295b558ad4d15134c90d0d115410a8 Mon Sep 17 00:00:00 2001
From: Klesti Selimaj <klesti.selimay@icloud.com>
Date: Tue, 19 May 2026 00:46:07 +0200
Subject: [PATCH] find mapping

---
 parser/src/rev_mapper/mod.rs | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/parser/src/rev_mapper/mod.rs b/parser/src/rev_mapper/mod.rs
index 90fc01e..f648d87 100644
--- a/parser/src/rev_mapper/mod.rs
+++ b/parser/src/rev_mapper/mod.rs
@@ -7,10 +7,10 @@ use pest_derive::Parser;
 #[grammar = "./src/rev_mapper/grammar.pest"]
 pub struct MistMapperParser;
 
-#[derive(Debug, Clone, Copy, Hash, PartialEq, Eq)]
+#[derive(Debug, Clone, Copy, Hash, PartialEq, Eq, PartialOrd, Ord)]
 pub struct MistMap(pub usize, pub usize);
 
-#[derive(Debug, Clone, Copy, Hash, PartialEq, Eq)]
+#[derive(Debug, Clone, Copy, Hash, PartialEq, Eq, PartialOrd, Ord)]
 pub struct RustMap(pub usize, pub usize);
 
 pub fn get_mapping(input: &str) -> HashSet<(RustMap, MistMap)> {
@@ -35,3 +35,14 @@ pub fn get_mapping(input: &str) -> HashSet<(RustMap, MistMap)> {
 
     mapping
 }
+
+pub fn find_mapping(
+    mapping: &HashSet<(RustMap, MistMap)>,
+    target: &RustMap,
+) -> Option<(RustMap, MistMap)> {
+    mapping
+        .iter()
+        .copied()
+        .filter(|(rust, _)| rust <= target)
+        .max_by_key(|(rust, _)| *rust)
+}