hanafuda/teyaku.c

#include "card.h"

int calculate_set_teyaku(Hand h) {
  int month_counts[12] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
  int month_stands[12] = { 0, 0, 0, 1, 1, 0, 1, 0, 0, 0, 0, 1 }; // TODO Pawlonia is weird
  for (int i = 0; i < h.count; i++) {
    Card c = h.cards[i];
    month_counts[c.month]++;
  }

  int triplets = 0, standing_triplets = 0, pairs = 0, four_of_a_kind = 0;
  for (int i = 0; i < 12; i++) {
    if (month_counts[i] == 4) {
      four_of_a_kind++;
    } else if (month_counts[i] == 3) {
      if (month_stands[i]) standing_triplets++;
      else triplets++;
    } else if (month_counts[i] == 2) {
      pairs++;
    }
  }
  int total_triplets = triplets + standing_triplets;

  if (four_of_a_kind && total_triplets) return 20; // 四三
  else if (four_of_a_kind && pairs) return 8; // 一二四
  else if (standing_triplets == 2) return 8; // 二立三本
  else if (total_triplets && pairs == 2) return 7; // 跳剣
  else if (triplets == 1 && standing_triplets == 1) return 7; // 三本立三本
  else if (four_of_a_kind) return 6; // 手四
  else if (triplets == 2) return 6; // 二三本
  else if (pairs == 3) return 4; // 二三本
  else if (standing_triplets) return 3; // 立三本
  else if (triplets) return 2; // 三本

  return 0;
}

int calculate_chaff_teyaku(Hand h) {
  int ribbons = 0;
  int animals = 0;
  int brights = 0;
  int chaff = 0;

  for (int i = 0; i < h.count; i++) {
    Card c = h.cards[i];
    if (c.month == NOVEMBER) chaff++; // November cards are all counted as chaff here
    else if (c.type == BRIGHT) brights++;
    else if (c.type == RIBBON) ribbons++;
    else if (c.type == ANIMAL) animals++;
    else chaff++;
  }

  if (chaff == 7) return 4; // 空素 - Empty Hand
  else if (chaff == 6 && brights == 1) return 4; // 光一 - One Bright
  else if (chaff == 6 && animals == 1) return 3; // 十一 - One Animal
  else if (chaff == 6 && ribbons == 1) return 3; // 短一 - One Ribbon
  else if (ribbons >= 2 && chaff == 7 - ribbons) return 2; // 赤 - Red
  else return 0;
}

int calculate_teyaku(Hand h) {
  return calculate_chaff_teyaku(h) + calculate_set_teyaku(h); 
}