//Fun/AdventCalendar2020/Day5-2.cpp
//Matthew Ellison
// Created: 12-05-20
//Modified: 12-05-20
//Find your seat id from the boarding passes


#include <iostream>
#include <fstream>
#include <string>
#include <vector>
#include "Stopwatch.hpp"
#include "Algorithms.hpp"


struct boardingPass{
	std::string passString;
	int rowNumber;
	int columnNumber;
	int seatId;
	void setPassString(std::string newPass){
		int minRow = 0;
		int maxRow = 127;
		//Set the whole string
		passString = newPass;
		//Determine the row the seat is in
		for(int cnt = 0;cnt < 7;++cnt){
			char half = newPass[cnt];
			//Keep the smaller half
			if(half == 'F'){
				maxRow = (minRow + maxRow) / 2;
			}
			//Keep the larger half
			else if(half == 'B'){
				minRow = ((minRow + maxRow) / 2) + 1;
			}
			else{
				std::cout << "ERROR! half must == F or B" << std::endl;
				exit(1);
			}
		}
		if(newPass[6] == 'F'){
			rowNumber = maxRow;
		}
		else{
			rowNumber = minRow;
		}
		int minSeat = 0;
		int maxSeat = 7;
		//Determine the column the seat is in
		for(int cnt = 7;cnt < 10;++cnt){
			char half = newPass[cnt];
			if(half == 'L'){
				maxSeat = (minSeat + maxSeat) / 2;
			}
			else if(half == 'R'){
				minSeat = ((minSeat + maxSeat) / 2) + 1;
			}
			else{
				std::cout << "ERROR! half must == R or L" << std::endl;
				exit(1);
			}
		}
		if(newPass[9] == 'L'){
			columnNumber = maxSeat;
		}
		else{
			columnNumber = minSeat;
		}
		//Determine the seatId
		seatId = (rowNumber * 8) + columnNumber;
	}
	//Compare according to seatId
	bool operator>(boardingPass& pass2){
		return seatId > pass2.seatId;
	}
	bool operator>=(boardingPass& pass2){
		return seatId >= pass2.seatId;
	}
	bool operator<(boardingPass& pass2){
		return seatId < pass2.seatId;
	}
	bool operator<=(boardingPass& pass2){
		return seatId <= pass2.seatId;
	}
	bool operator==(boardingPass& pass2){
		return seatId == pass2.seatId;
	}
};


std::vector<boardingPass> importData(){
	std::vector<boardingPass> boardingPasses;
	std::ifstream inputFile("inputs/Day5.txt");	//Open the input file

	//Go through every element in the file and set it in the vector
	int cnt = 1;
	while(!inputFile.eof()){
		boardingPass pass;
		std::string currentPass;
		inputFile >> currentPass;
		if(!currentPass.empty()){
			pass.setPassString(currentPass);
		}
		++cnt;
		boardingPasses.push_back(pass);
	}

	return boardingPasses;
}


int main(){
	mee::Stopwatch timer;
	std::vector<boardingPass> passes = importData();
	int yourSeatId;

	//Start the timer
	timer.start();


	//Sort the list of passes by seatId
	std::sort(passes.begin(), passes.end());

	//Go through every pass in the list (except the ends) and your seat id should be one where seats on both sides are +/-1 off of yours
	for(int cnt = 1;cnt < (passes.size() - 1);++cnt){
		if(passes[cnt - 1].seatId == (passes[cnt].seatId - 2)){
			yourSeatId = passes[cnt].seatId - 1;
			break;
		}
	}

	//Stop the timer
	timer.stop();

	//Print the results
	std::cout << "Your seatId = " << yourSeatId
			<<"\nIt took " << timer.getStr() << " to finish this problem" << std::endl;

	return 0;
}

/* Results:
Your seatId = 612
It took 0.000 nanoseconds to finish this problem
*/