#include <chrono>
#include <iostream>
#include <vector>
#include <tuple>
#include <algorithm>
#include <array>

const int arr_sz = 12001;
typedef std::array<int, arr_sz> arr_2k;

int F_Day25_Exec(std::vector<std::vector<int>>& instr, int& state, arr_2k& tape, int& pos)
{
    if (tape[pos] == 0)
    {
        tape[pos] = instr[state][0];
        pos += instr[state][1];
        state = instr[state][2];
    }
    else
    {
        tape[pos] = instr[state][3];
        pos += instr[state][4];
        state = instr[state][5];
    }
    return 1;
}

// use array instead of map. std::array?

int Day25(void)
{
    std::chrono::high_resolution_clock::time_point t1 = std::chrono::high_resolution_clock::now();

    fs::path path("../../_Input/input_Day25.txt");
    //fs::path path("../../_Input/input_Day25_test.txt");
    int res_p1 = 4225;

    std::vector<std::vector<std::string>> sinp = F_Split_vString(F_Read_File_To_Array(path), ' ');
    while (sinp.back().size() == 0)
    {
        sinp.pop_back();
    }
    int state = F_Alphabetic_Number(sinp[0][sinp[0].size() - 1][0])-1;
    int steps = std::stoi(sinp[1][sinp[1].size() - 2]);
    sinp.erase(sinp.begin(), sinp.begin() + 3);

    int pos = (arr_sz - 1)/6;
    arr_2k tape;
    tape.fill(0);

    std::vector<std::vector<int>> instructions;
    for (int i = 0; i < (sinp.size() + 1) / 10; i++)            // 9 line per instruction + one empty line in between. so 9 lines for first instruction, 10 for all others
    {
        int ind = i * 10;
        std::vector<int> t;                         // lines 0 - 8 for each instr

        for (int j = 0; j < 2; j++)
        {
            t.push_back(sinp[j * 4 + ind + 2][sinp[j * 4 + ind + 2].size() - 1][0] - '0');      // value to write in [0] and [3]

            std::string sdir = sinp[j * 4 + ind + 3][sinp[j * 4 + ind + 3].size() - 1];
            int dir = (sdir == "left." ? -1 : 1);
            t.push_back(dir);                                                                                       // direction to [1] and [4]. right = 1, left = -1

            t.push_back(F_Alphabetic_Number(sinp[j * 4 + ind + 4][sinp[j * 4 + ind + 4].size() - 1][0])-1);     // new state in [2] and [5]
        }
        instructions.push_back(t);
        //backup for instructions map: instructions[F_Alphabetic_Number(sinp[ind][sinp[ind].size() - 1][0])] = t;
    }

    for (int i = 0; i < steps; i++)
    {
        F_Day25_Exec(instructions, state, tape, pos);
    }

    int sum = std::accumulate(tape.begin(), tape.end(), 0);
    cout << "Day25-Part1: " << sum << (sum == res_p1 ? ". Correct." : ". Wrong.") << endl;
    F_Print_Time("Day25 duration: ", t1);
    return 1;
}