feat: compute knight attack table

1 files changed, 22 insertions, 9 deletions

diff --git a/src/main.c b/src/main.c
index 75d3bb7..2e95970 100644
--- a/src/main.c
+++ b/src/main.c
@@ -1,17 +1,30 @@
 #include "unittest.h"
 #include "board.h"
 
-void test_notations() {
-  printf("%u\n", notation_to_index('e', 4));
-  unit_test(notation_to_index('e', 4) == 28, "Notation e4 is index 28");
+int main() {
+  { // Pop count
+    unit_test(pop_count(0b01110) == 3, "Pop count of 01110 is 3");
+  }
 
-  char notation[2] = "x0";
-  index_to_notation(28, notation);
-  unit_test(notation[0] == 'e' && notation [1] == '4', "Index 28 is notation e4");
-}
+  { // Test knight attacks
+    Bitboard attacks[64];
+    precompute_knight_attack_table(attacks);
 
-int main() {
-  test_notations();
+    int max_attacks = 0;
+    for (int i = 0; i < 64; i++) {
+      int attack_count = pop_count(attacks[i]);
+      if (attack_count > max_attacks) max_attacks = attack_count;
+    }
+    unit_test(max_attacks == 8, "Max amount of knight attacks should be 8");
+
+    { // Knight on b7 attack table
+      U64 bit = 1;
+      unit_test(
+          attacks[b7] == ((bit << d8) | (bit << d6) | (bit << c5) | (bit << a5)),
+          "Knight on b7 attacks d8, d6, c5, a5"
+      );
+    }
+  }
 
   report();
   return 0;