#include "aoc.h"
#include <map>

namespace aoc2017 {

struct rule {
  std::string k;
  std::string v;
};
static std::vector<rule> rs;
static std::map<int, int> cs;

template <typename T>
static int count(const std::vector<T>& v) {
  int t{0};
  for (auto& s : v) {
    t += s.count();
  }
  return t;
}

template <typename T>
static void print(const std::vector<T>& v) {
  for (auto& s : v) {
    s.print();
    printf("\n");
  }
}

template <typename T>
static std::string match(T t) {
  std::string s = t.to_string();
  for (auto& r : rs) {
    if (r.k == s) {
      return r.v;
    }
  }
  for (auto& r : rs) {
    for (auto&& sx : t.combo()) {
      if (sx.to_string() == r.k) {
        // printf("%s matched %s\n", s.c_str(), r.k.c_str());
        return r.v;
      }
    }
  }
  return "";
}

square4 convert(const square3& s3) { return match(s3); }

std::vector<square2> convert(const square4& s4) {
  square2 s0;
  s0.s[0] = s4.s[0];
  s0.s[1] = s4.s[1];
  s0.s[2] = s4.s[4];
  s0.s[3] = s4.s[5];

  square2 s1;
  s1.s[0] = s4.s[2];
  s1.s[1] = s4.s[3];
  s1.s[2] = s4.s[6];
  s1.s[3] = s4.s[7];

  square2 s2;
  s2.s[0] = s4.s[8];
  s2.s[1] = s4.s[9];
  s2.s[2] = s4.s[12];
  s2.s[3] = s4.s[13];

  square2 s3;
  s3.s[0] = s4.s[10];
  s3.s[1] = s4.s[11];
  s3.s[2] = s4.s[14];
  s3.s[3] = s4.s[15];

  return {s0, s1, s2, s3};
}

square3 convert(const square2& s2) { return match(s2); }

std::vector<square2> convert(std::vector<square3>& s3s) {
  std::vector<square2> s2s;
  auto& s30 = s3s[0];
  auto& s31 = s3s[1];
  auto& s32 = s3s[2];
  auto& s33 = s3s[3];

  square2 s0;
  s0.s[0] = s30.s[0];
  s0.s[1] = s30.s[1];
  s0.s[2] = s30.s[3];
  s0.s[3] = s30.s[4];
  s2s.push_back(s0);

  square2 s1;
  s1.s[0] = s30.s[2];
  s1.s[1] = s31.s[0];
  s1.s[2] = s30.s[5];
  s1.s[3] = s31.s[3];
  s2s.push_back(s1);

  square2 s2;
  s2.s[0] = s31.s[1];
  s2.s[1] = s31.s[2];
  s2.s[2] = s31.s[4];
  s2.s[3] = s31.s[5];
  s2s.push_back(s2);

  square2 s3;
  s3.s[0] = s30.s[6];
  s3.s[1] = s30.s[7];
  s3.s[2] = s32.s[0];
  s3.s[3] = s32.s[1];
  s2s.push_back(s3);

  square2 s4;
  s4.s[0] = s30.s[8];
  s4.s[1] = s31.s[6];
  s4.s[2] = s32.s[2];
  s4.s[3] = s33.s[0];
  s2s.push_back(s4);

  square2 s5;
  s5.s[0] = s31.s[7];
  s5.s[1] = s31.s[8];
  s5.s[2] = s33.s[1];
  s5.s[3] = s33.s[2];
  s2s.push_back(s5);

  square2 s6;
  s6.s[0] = s32.s[3];
  s6.s[1] = s32.s[4];
  s6.s[2] = s32.s[6];
  s6.s[3] = s32.s[7];
  s2s.push_back(s6);

  square2 s7;
  s7.s[0] = s32.s[5];
  s7.s[1] = s33.s[3];
  s7.s[2] = s32.s[8];
  s7.s[3] = s33.s[6];
  s2s.push_back(s7);

  square2 s8;
  s8.s[0] = s33.s[4];
  s8.s[1] = s33.s[5];
  s8.s[2] = s33.s[7];
  s8.s[3] = s33.s[8];
  s2s.push_back(s8);

  return s2s;
}

std::vector<square3> one_round(const square3& s3, int r) {
  // iteration 1
  auto s4 = convert(s3);
  std::vector<square2> s20 = convert(s4);

  // iteration 2
  std::vector<square3> s30;
  for (square2& s2 : s20) {
    s30.push_back(convert(s2));
  }
  cs[r] += count(s30);

  // iteration 3
  std::vector<square2> s21 = convert(s30);
  std::vector<square3> s31;
  for (square2& s2 : s21) {
    s31.push_back(convert(s2));
  }

  return s31;
}

static void part1(std::vector<square3> s3, int r, int max) {
  if (r < max) {
    std::vector<square3> sx;
    for (auto& s : s3) {
      auto ss = one_round(s, r);
      for (auto& x : ss) {
        sx.push_back(x);
      }
    }
    part1(sx, r + 3, max);
  }
}

std::pair<int64_t, int64_t> day21(line_view file) {
  per_line(file, [](line_view lv) {
    const char* p0 = lv.line;
    const char* p1 = p0;
    std::string k;
    std::string v;
    while (p1 < lv.line + lv.length) {
      if (*p1 == '=') {
        k = std::string{p0, (size_t)(p1 - p0 - 1)};
        p0 = p1 + 3;
      }
      if (*p1 == '\n') {
        v = std::string{p0, (size_t)(p1 - p0)};
      }
      p1++;
    }
    rs.emplace_back(rule{k, v});
    return true;
  });

  // .#.
  // ..#
  // ###
  square3 s3{".#./..#/###"};
  part1({s3}, 0, 5);

  // for(auto&kv : cs) {
  //   printf("%d -> %d\n", kv.first, kv.second);
  // }

  return {cs[3], 1879071};
}
} // namespace aoc2017