From 37aa23720923b93f15079603edc3ea726151afbf Mon Sep 17 00:00:00 2001
From: Lyle Mantooth <lyle@menteeth.us>
Date: Wed, 31 Jan 2024 15:49:41 -0500
Subject: [PATCH] Parse "#REPLACE" macro in MML.

---
 Cargo.lock  |  2 +-
 Cargo.toml  |  2 +-
 flake.nix   |  2 +-
 src/lib.rs  |  1 +
 src/mfvi.rs | 28 ++++++++++++++++++++++++++++
 5 files changed, 32 insertions(+), 3 deletions(-)
 create mode 100644 src/lib.rs
 create mode 100644 src/mfvi.rs

diff --git a/Cargo.lock b/Cargo.lock
index b3a9899..8670b04 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -3,5 +3,5 @@
 version = 3
 
 [[package]]
-name = "quick-start"
+name = "slamshuffle"
 version = "0.1.0"
diff --git a/Cargo.toml b/Cargo.toml
index 3e2467c..564d871 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,5 +1,5 @@
 [package]
-name = "quick-start"
+name = "slamshuffle"
 version = "0.1.0"
 edition = "2021"
 license = "MIT"
diff --git a/flake.nix b/flake.nix
index 5eb191d..284615d 100644
--- a/flake.nix
+++ b/flake.nix
@@ -1,5 +1,5 @@
 {
-  description = "Build a cargo project";
+  description = "Music randomizer for Worlds Collide, based on johnnydmad";
 
   inputs = {
     nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
diff --git a/src/lib.rs b/src/lib.rs
new file mode 100644
index 0000000..b0011ee
--- /dev/null
+++ b/src/lib.rs
@@ -0,0 +1 @@
+pub mod mfvi;
diff --git a/src/mfvi.rs b/src/mfvi.rs
new file mode 100644
index 0000000..474aea1
--- /dev/null
+++ b/src/mfvi.rs
@@ -0,0 +1,28 @@
+struct Translation<'a> {
+    find: &'a str,
+    replacement: &'a str,
+}
+
+pub fn replace_chars(input: &str) -> String {
+    let trs: Vec<Translation<'_>> = input
+        .lines()
+        .filter_map(|line| {
+            line.strip_prefix("#REPLACE ")
+                .and_then(|l| l.rsplit_once(' '))
+                .and_then(|(first, second)| {
+                    let length = std::cmp::min(first.len(), second.len());
+                    Some(Translation {
+                        find: &first[0..length],
+                        replacement: &second[0..length],
+                    })
+                })
+        })
+        .collect();
+
+    let mut new = input.to_string();
+    for tr in trs {
+        new = new.replace(tr.find, tr.replacement);
+    }
+
+    new
+}