begin jiang

jiang/Cargo.toml

@@ -0,0 +1,7 @@
+[package]
+name = "jiang"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]
+jong-types.workspace = true

jiang/src/lib.rs

@@ -0,0 +1,68 @@
+use std::collections::HashMap;
+
+use jong_types::*;
+
+// pub fn check_valid() {}
+
+pub enum Meldable {
+    Ron,
+    Chii(Tile, Tile),
+    Pon,
+    Kan,
+}
+
+pub fn find_meldables(hand: &[Tile], dealt: Tile) -> Vec<Meldable> {
+    let counts = hand.iter().fold(HashMap::new(), |mut m, t| {
+        let e = m.entry(t).or_insert(0);
+        *e += 1;
+        m
+    });
+
+    let mut calls = vec![];
+
+    // find pon & kan
+    if let Some(&count) = counts.get(&dealt) {
+        if count == 3 {
+            calls.push(Meldable::Kan)
+        } else if count == 2 {
+            calls.push(Meldable::Pon)
+        }
+    }
+
+    // find chii
+    if let Some(next_outer) = dealt.next_rank() {
+        if let Some(next_inner) = next_outer.next_rank()
+            && counts.contains_key(&next_outer)
+            && counts.contains_key(&next_inner)
+        {
+            calls.push(Meldable::Chii(next_outer, next_inner));
+        }
+        if let Some(prev_inner) = next_outer.prev_rank()
+            && counts.contains_key(&next_outer)
+            && counts.contains_key(&prev_inner)
+        {
+            calls.push(Meldable::Chii(next_outer, prev_inner));
+        }
+    }
+    if let Some(prev_outer) = dealt.prev_rank()
+        && let Some(prev_inner) = prev_outer.prev_rank()
+        && counts.contains_key(&prev_outer)
+        && counts.contains_key(&prev_inner)
+    {
+        calls.push(Meldable::Chii(prev_outer, prev_inner));
+    }
+
+    // find ron
+
+    calls
+}
+
+fn count_shapes(hand: &[Tile]) {
+    let hand = if !hand.is_sorted() {
+        let mut hand = hand.to_vec();
+        hand.sort();
+        &hand
+    } else {
+        hand
+    };
+}