feat: replace fastrand by rapidhash with custom generator

Cargo.lock

@@ -3,14 +3,14 @@
 version = 4
 
 [[package]]
-name = "fastrand"
-version = "2.3.0"
+name = "rapidhash"
+version = "1.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "37909eebbb50d72f9059c3b6d82c0463f2ff062c9e95845c43a6c9c0355411be"
+checksum = "9813f789f95ee4fe6b4d01834404d7cccacbc3f6c029343af910b3c2835eb9f1"
 
 [[package]]
 name = "rpg"
 version = "1.0.0"
 dependencies = [
- "fastrand",
+ "rapidhash",
 ]

Cargo.toml

@@ -4,4 +4,4 @@ version = "1.0.0"
 edition = "2021"
 
 [dependencies]
-fastrand = "2.3.0"
+rapidhash = "1.4.0"

src/main.rs

@@ -1,4 +1,30 @@
-use std::env;
+use std::hash::Hasher;
+use std::time::{SystemTime, UNIX_EPOCH};
+use std::{env, ops::Range};
+use rapidhash::RapidInlineHasher;
+
+pub struct HashRng {
+    state: u64,
+    counter: u64,
+}
+
+impl HashRng {
+    pub fn new() -> Self {
+        let seed = SystemTime::now()
+            .duration_since(UNIX_EPOCH)
+            .unwrap_or_default()
+            .as_nanos() as u64; // Tronqué à u64
+        Self { state: seed, counter: 0 }
+    }
+
+    pub fn next_in_range(&mut self, range: Range<usize>) -> usize {
+        let mut hasher = RapidInlineHasher::new(self.state);
+        hasher.write_u64(self.state);
+        hasher.write_u64(self.counter);
+        self.counter = self.counter.wrapping_add(1);
+        range.start + (hasher.finish() as usize % (range.end - range.start))
+    }
+}
 
 fn main() {
     let num_pseudonyms = env::args()
@@ -9,12 +35,12 @@ fn main() {
     let adjectives = include_str!("../data/adjectives.txt").lines().collect::<Vec<_>>();
     let nouns = include_str!("../data/nouns.txt").lines().collect::<Vec<_>>();
 
-    (0..num_pseudonyms).for_each(|_| {
-        println!(
-            "{}-{}-{}",
-            adjectives[fastrand::usize(0..adjectives.len())],
-            nouns[fastrand::usize(0..nouns.len())],
-            fastrand::u32(0..1000)
-        );
-    });
+    let mut rng = HashRng::new();
+
+    for _ in 0..num_pseudonyms {
+        let adjective = adjectives[rng.next_in_range(0..adjectives.len())];
+        let noun = nouns[rng.next_in_range(0..nouns.len())];
+        let number = rng.next_in_range(0..1000);
+        println!("{adjective}-{noun}-{number}");
+    }
 }