Added build.rs to generate dict files

Cargo.toml

@@ -7,3 +7,6 @@ edition = "2021"
 
 [dependencies]
 xz2 = "0.1.7"
+
+[build-dependencies]
+xz2 = "0.1.7"

README.md

@@ -6,4 +6,6 @@ I'm learning Rust, so this is just a rewrite of an simple old project in Rust.
 
 ### Note
 
-The main `src/wordlist` was pulled from [words_alpha.txt by dwyl](https://github.com/dwyl/english-words/) and processed using Rust. Processing code was really simple, so didn't put it up here. The processing included pre-sorting every line in `src/wordlist` to create `src/wordlist_sorted` and then compressing both using `xz`.
+The main `src/wordlist` was pulled from [words_alpha.txt by dwyl](https://github.com/dwyl/english-words/).
+
+In order to use a different `wordlist.txt`, place the file inside `src/` and delete the `*.xz` files there. Then run `cargo build` or `cargo build --release`.

build.rs

@@ -0,0 +1,59 @@
+use std::{fs, io::Read};
+use xz2::read::XzEncoder;
+
+fn main() {
+    // check if the compressed dictionary files exist, run if missing
+    // so, in order to rebuild the compressed files, just delete them
+    if !fs::metadata("src/dict/wordlist.txt.xz").is_ok() {
+        compress_wordlist();
+    }
+    if !fs::metadata("src/dict/wordlist_sorted.txt.xz").is_ok() {
+        compress_sorted_wordlist();
+    }
+}
+
+fn compress_wordlist() {
+    // specify location for dictionary files and read wordlist.txt
+    let dict_dir = "src/dict/";
+    let wordlist = fs::read_to_string([dict_dir, "wordlist.txt"].join(""))
+        .expect("The file wordlist.txt is missing!");
+    // compress wordlist.txt using xz compression and save it
+    let wordlist_bytes = wordlist.as_bytes();
+    let mut compressor = XzEncoder::new(wordlist_bytes, 9);
+    let mut compressed_wordlist = Vec::new();
+    compressor.read_to_end(&mut compressed_wordlist).unwrap();
+    fs::write([dict_dir, "wordlist.txt.xz"].join(""), compressed_wordlist).unwrap();
+}
+
+fn compress_sorted_wordlist() {
+    // specify location for dictionary files
+    let dict_dir = "src/dict/";
+
+    // create wordlist_sorted from wordlist.txt
+    let wordlist = fs::read_to_string([dict_dir, "wordlist.txt"].join(""))
+        .expect("The file wordlist.txt is missing!");
+    let mut wordlist_sorted = String::new();
+    for word in wordlist.split_terminator("\n") {
+        wordlist_sorted = [wordlist_sorted, sorted(word), "\n".to_string()].join("");
+    }
+
+    //compress wordlist_sorted using xz compression and save it
+    let wordlist_sorted_bytes = wordlist_sorted.as_bytes();
+    let mut compressor_sorted = XzEncoder::new(wordlist_sorted_bytes, 9);
+    let mut compressed_wordlist_sorted = Vec::new();
+    compressor_sorted
+        .read_to_end(&mut compressed_wordlist_sorted)
+        .unwrap();
+    fs::write(
+        [dict_dir, "wordlist_sorted.txt.xz"].join(""),
+        compressed_wordlist_sorted,
+    )
+    .unwrap();
+}
+
+// function for sorting
+fn sorted(word: &str) -> String {
+    let mut word_chars: Vec<char> = word.chars().collect();
+    word_chars.sort_by(|a, b| a.cmp(b));
+    String::from_iter(word_chars)
+}