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#include "common.h"
#include <vector>

namespace aoc2022 {

struct sensor {
  struct pos {
    int x = 0;
    int y = 0;

    pos() {}
    pos(int i, int j) : x(i), y(j) {}
    bool operator==(pos px) const noexcept { return x == px.x && y == px.y; }

    bool operator<(pos px) const noexcept { return x < px.x ? true : x > px.x ? false : y < px.y; }
  };

  struct line {
    pos p0;
    pos p1;

    line() {}
    line(pos x, pos y) : p0(x), p1(y) {}
    friend bool operator<(const line& l1, const line& l2) { return l1.p0.x < l2.p0.x; }
  };

  pos ps[2] = {{0, 0}, {0, 0}};

  static int mdistance(pos p1, pos p2) { return std::abs(p1.x - p2.x) + std::abs(p1.y - p2.y); }

  std::pair<int, std::vector<line>> lines() const noexcept {
    auto d = mdistance(ps[0], ps[1]);
    std::vector<line> ls;
    for (int y = ps[0].y - d; y <= ps[0].y + d; y++) {
      auto dx = d - std::abs(ps[0].y - y);
      pos p0 = {ps[0].x - dx, y};
      pos p1 = {ps[0].x + dx, y};
      ls.emplace_back(p0, p1);
    }
    return {ps[0].y - d, ls};
  }

  void get_number(const char** pp, int* d) {
    const char* p = *pp;
    int sign = 1;
    if (*p == '-') {
      sign = -1;
      p++;
    }
    while (*p >= '0' && *p <= '9') {
      *d = *d * 10 + *p - '0';
      p++;
    }
    *d *= sign;
    *pp = p;
  }

  void print() { printf("S(%d, %d) B(%d, %d)\n", ps[0].x, ps[0].y, ps[1].x, ps[1].y); }

  sensor(line_view lv) {
    const char* p = lv.line;
    int* is[] = {&ps[0].x, &ps[0].y, &ps[1].x, &ps[1].y};
    int n{0};
    while (p < lv.line + lv.length) {
      if (*p == '=') {
        const char* p0 = p + 1;
        get_number(&p0, is[n]);
        p = p0;
        n++;
      }
      p++;
    }
  }

  bool operator<(const sensor& s) const noexcept { return ps[0].x < s.ps[0].x; }
};

std::pair<int, size_t> day15(line_view);
} // namespace aoc2022