From d5490890635985720489a1760f623dc692e8b4e7 Mon Sep 17 00:00:00 2001
From: Correl Roush <correl@gmail.com>
Date: Tue, 8 May 2012 00:46:15 -0400
Subject: [PATCH] Initial hand scoring, handles Daisangen only

---
 include/riichi.hrl    | 11 +++++++++++
 src/riichi.erl        | 28 +++++++++++++++++++++++++++-
 test/riichi_tests.erl | 11 +++++++++++
 3 files changed, 49 insertions(+), 1 deletion(-)

diff --git a/include/riichi.hrl b/include/riichi.hrl
index 719a458..9b45447 100644
--- a/include/riichi.hrl
+++ b/include/riichi.hrl
@@ -2,3 +2,14 @@
     suit,
     value
 }).
+
+-record(hand, {
+    tiles=[],
+    sets=[]
+}).
+
+-record(set, {
+    count,
+    tile,
+    open=true
+}).
diff --git a/src/riichi.erl b/src/riichi.erl
index f6ad0c3..ad36006 100644
--- a/src/riichi.erl
+++ b/src/riichi.erl
@@ -6,7 +6,10 @@
     is_valid_tile/1,
     dora/1,
     nearest/2,
-    score/3
+    score/3,
+    score_hand/1,
+    score_hand/2,
+    score_hand/3
 ]).
 
 is_valid_tile(#tile{suit=dragon, value=Value}) ->
@@ -71,3 +74,26 @@ score(Fu, Han, Limit) ->
         true ->
             Score
     end.
+
+score_hand(#hand{}=H) ->
+    score_hand(H, 20).
+
+score_hand(#hand{}=H, Fu) ->
+    score_hand(H, Fu, true).
+
+score_hand(#hand{tiles=T, sets=_S}=_H, BaseFu, Limit) ->
+    Fu = [
+        BaseFu
+    ],
+    Han = [
+        _DaiSanGen = case sets:is_subset(sets:from_list([{3, #tile{suit=dragon, value=red}}, {3, #tile{suit=dragon, value=white}}, {3, #tile{suit=dragon, value=green}}]), sets:from_list(find_sets(T))) of
+            true -> 13;
+            _ -> 0
+        end
+    ],
+    score(lists:sum(Fu), lists:sum(Han), Limit).
+
+find_sets(Tiles) ->
+    Unique = sets:to_list(sets:from_list(Tiles)),
+    [{length(lists:filter(fun(X) -> X == T end, Tiles)), T}
+    || T <- Unique].
diff --git a/test/riichi_tests.erl b/test/riichi_tests.erl
index 3ac0e24..a602b65 100644
--- a/test/riichi_tests.erl
+++ b/test/riichi_tests.erl
@@ -82,3 +82,14 @@ score_fu_limit_test() ->
 
 score_rounded_test() ->
     ?assertEqual(riichi:score(20, 1, true), 200). % 160 rounded up
+
+score_hand_dai_san_gan_test() ->
+    Hand = #hand{
+        tiles = lists:flatten([
+            lists:duplicate(3, #tile{suit=dragon, value=red}),
+            lists:duplicate(3, #tile{suit=dragon, value=white}),
+            lists:duplicate(3, #tile{suit=dragon, value=green}),
+            lists:duplicate(3, #tile{suit=wind, value=east}),
+            lists:duplicate(2, #tile{suit=wind, value=north})])
+    },
+    ?assertEqual(riichi:score_hand(Hand, 30), 8000).