#define OLC_PGE_APPLICATION
#include "pixelGameEngine.h"
#include "olcutils.h"

using namespace olc;

const vi2d INVALID={-9999999,-99999999};

enum Direction{
    NORTH,
    EAST,
    SOUTH,
    WEST
};

struct Elf{
    vi2d pos;
    int orderMarker=0;
    std::array<Direction,4>orderList={Direction::NORTH,Direction::SOUTH,Direction::WEST,Direction::EAST};
    vi2d dest=INVALID;
};

vi2d upperLeft={0,0};
vi2d lowerRight={0,0};

std::map<vi2d,Elf>elves;

int iterations=1;

int main()
{
    std::ifstream file("input");
    int y=0;
    while (file.good()){
        std::string line;
        std::getline(file,line);
        if (line.length()>0){
            std::cout<<line<<std::endl;
            for (int i=0;i<line.length();i++){
                if (line[i]=='#'){
                    elves[{i,y}]={{i,y}};
                }
            }
            lowerRight={(int)line.length()-1,y++};
        }
    }
    std::cout<<elves.size()<<" elves loaded."<<std::endl;
    while (true){
        std::map<vi2d,vi2d>plannedMoves;
        for (std::map<vi2d,Elf>::iterator it=elves.begin();it!=elves.end();++it){
            Elf&e=elves[it->first];
            int neighbors=0;
            for (int x=-1;x<=1;x++){
                for (int y=-1;y<=1;y++){
                    if (x!=0||y!=0){
                        if (elves.find({x+it->first.x,y+it->first.y})!=elves.end()){
                            neighbors++;
                            goto neighborCheck;
                        }
                    }
                }
            }
            neighborCheck:
            if (neighbors>0){
                for (int j=0;j<e.orderList.size();j++){
                    Direction orderDir=e.orderList[j];
                    switch (orderDir){
                        case NORTH:{
                            if (elves.find({it->first.x,it->first.y-1})==elves.end()&&
                                elves.find({it->first.x-1,it->first.y-1})==elves.end()&&
                                elves.find({it->first.x+1,it->first.y-1})==elves.end()
                                ){
                                    vi2d dest={it->first.x,it->first.y-1};
                                    if (plannedMoves.find(dest)!=plannedMoves.end()){
                                        if (elves.find(plannedMoves[dest])==elves.end()){
                                            std::cout<<"WARNING! Could not find Elf @"<<plannedMoves[dest]<<std::endl;
                                        }
                                        elves[plannedMoves[dest]].dest=INVALID;
                                        //std::cout<<"Overlap found! Invalidated elves attempting to move to "<<plannedMoves[dest]<<std::endl;
                                    } else {
                                        plannedMoves[dest]=it->first;
                                        e.dest=dest;
                                        //std::cout<<"Elf @"<<it->first<<"Plans to move NORTH"<<std::endl;
                                    }
                                    goto orderComplete;
                                }
                        }break;
                        case SOUTH:{
                            if (elves.find({it->first.x,it->first.y+1})==elves.end()&&
                                elves.find({it->first.x-1,it->first.y+1})==elves.end()&&
                                elves.find({it->first.x+1,it->first.y+1})==elves.end()
                                ){
                                    vi2d dest={it->first.x,it->first.y+1};
                                    if (plannedMoves.find(dest)!=plannedMoves.end()){
                                        if (elves.find(plannedMoves[dest])==elves.end()){
                                            std::cout<<"WARNING! Could not find Elf @"<<plannedMoves[dest]<<std::endl;
                                        }
                                        elves[plannedMoves[dest]].dest=INVALID;
                                        //std::cout<<"Overlap found! Invalidated elves attempting to move to "<<plannedMoves[dest]<<std::endl;
                                    } else {
                                        plannedMoves[dest]=it->first;
                                        e.dest=dest;
                                        //std::cout<<"Elf @"<<it->first<<"Plans to move SOUTH"<<std::endl;
                                    }
                                    goto orderComplete;
                                }
                        }break;
                        case WEST:{
                            if (elves.find({it->first.x-1,it->first.y})==elves.end()&&
                                elves.find({it->first.x-1,it->first.y-1})==elves.end()&&
                                elves.find({it->first.x-1,it->first.y+1})==elves.end()
                                ){
                                    vi2d dest={it->first.x-1,it->first.y};
                                    if (plannedMoves.find(dest)!=plannedMoves.end()){
                                        if (elves.find(plannedMoves[dest])==elves.end()){
                                            std::cout<<"WARNING! Could not find Elf @"<<plannedMoves[dest]<<std::endl;
                                        }
                                        elves[plannedMoves[dest]].dest=INVALID;
                                    } else {
                                        plannedMoves[dest]=it->first;
                                        e.dest=dest;
                                    }
                                        //std::cout<<"Elf @"<<it->first<<"Plans to move WEST"<<std::endl;
                                    goto orderComplete;
                                }
                        }break;
                        case EAST:{
                            if (elves.find({it->first.x+1,it->first.y})==elves.end()&&
                                elves.find({it->first.x+1,it->first.y-1})==elves.end()&&
                                elves.find({it->first.x+1,it->first.y+1})==elves.end()
                                ){
                                    vi2d dest={it->first.x+1,it->first.y};
                                    if (plannedMoves.find(dest)!=plannedMoves.end()){
                                        if (elves.find(plannedMoves[dest])==elves.end()){
                                            std::cout<<"WARNING! Could not find Elf @"<<plannedMoves[dest]<<std::endl;
                                        }
                                        elves[plannedMoves[dest]].dest=INVALID;
                                        //std::cout<<"Overlap found! Invalidated elves attempting to move to "<<plannedMoves[dest]<<std::endl;
                                    } else {
                                        plannedMoves[dest]=it->first;
                                        e.dest=dest;
                                    }
                                    //std::cout<<"Elf @"<<it->first<<"Plans to move EAST"<<std::endl;
                                    goto orderComplete;
                                }
                        }break;
                    }
                }
                orderComplete:;
            }
        }
        upperLeft={0,0};
        lowerRight={0,0};
        std::map<vi2d,Elf>newElves;
        bool moved=false;
        for (std::map<vi2d,Elf>::iterator it=elves.begin();it!=elves.end();++it){
            Elf&e=elves[it->first];
            if (e.dest!=INVALID){
                e.pos=e.dest;
                if (e.dest.x<upperLeft.x){
                    upperLeft.x=e.dest.x;
                }
                if (e.dest.y<upperLeft.y){
                    upperLeft.y=e.dest.y;
                }
                if (e.dest.x>lowerRight.x){
                    lowerRight.x=e.dest.x;
                }
                if (e.dest.y>lowerRight.y){
                    lowerRight.y=e.dest.y;
                }
                e.dest=INVALID;
                Direction temp=e.orderList[0];
                for (int j=0;j<e.orderList.size()-1;j++){
                    Direction&dir=e.orderList[j];
                    dir=e.orderList[j+1];
                }
                Direction&tempDir=e.orderList[e.orderList.size()-1];
                tempDir=temp;
                /*std::cout<<"Next orders: ";
                for (int j=0;j<e.orderList.size();j++){
                    std::cout<<e.orderList[j];
                }
                std::cout<<std::endl;*/
                moved=true;
            } else {
                if (e.pos.x<upperLeft.x){
                    upperLeft.x=e.pos.x;
                }
                if (e.pos.y<upperLeft.y){
                    upperLeft.y=e.pos.y;
                }
                if (e.pos.x>lowerRight.x){
                    lowerRight.x=e.pos.x;
                }
                if (e.pos.y>lowerRight.y){
                    lowerRight.y=e.pos.y;
                }
                Direction temp=e.orderList[0];
                for (int j=0;j<e.orderList.size()-1;j++){
                    Direction&dir=e.orderList[j];
                    dir=e.orderList[j+1];
                }
                Direction&tempDir=e.orderList[e.orderList.size()-1];
                tempDir=temp;
                /*std::cout<<"Next orders: ";
                for (int j=0;j<e.orderList.size();j++){
                    std::cout<<e.orderList[j];
                }
                std::cout<<std::endl;*/
            }
            newElves[e.pos]=e;
        }
        
        elves=newElves;
        if (!moved){
            break;
        }
        iterations++;
    }
    for (int y=upperLeft.y;y<=lowerRight.y;y++){
        for (int x=upperLeft.x;x<=lowerRight.x;x++){
            if (elves.find({x,y})==elves.end()){
                std::cout<<'.';
            } else {
                std::cout<<'#';
            }
        }
        std::cout<<std::endl;
    }

    int sum=0;
    for (int x=upperLeft.x;x<=lowerRight.x;x++){
        for (int y=upperLeft.y;y<=lowerRight.y;y++){
            if (elves.find({x,y})==elves.end()){
                sum++;
            }
        }
    }

    std::cout<<"Iteration Count: "<<iterations<<std::endl;

	return 0;
}