connect4.cc

#include <ncurses.h>
#include <iostream>
#include <random>
#include <utility>
#include "ai.h"
#include "game.h"
#include <cstring>

// The main game loop for Connect 4.
// *** Utility functions only used in this file. ***

// Switches from player 1 to player 2 and vice-versa.
int SwitchPlayer(int player);

// Get a move from the human. Updates UI to show column selection.
bool GetPlayerMove(int board[6][7], int &move);

// Plays a single game.
int PlayGame(std::pair<PlayerType, PlayerType> players, bool silent);

int main(int argc, char **argv) {
  srand(time(0));

  std::pair<PlayerType, PlayerType> players;
  if (argc == 3) {
    players = std::make_pair(GetPlayerType(argv[1]), GetPlayerType(argv[2])); // Keeping track of the amount of wins and loses
  } else if (argc == 1) {
    players = std::make_pair(PlayerType::kHuman, PlayerType::kRandom); // kHuman is one ai the other ai is kRandom
  } else {
    std::cerr << "Usage: ./connect4 [player1] [player2]" << std::endl;
    return 1;
  }

  // Show the screen if either player is a human.
  bool silent = true;
  if (players.first == PlayerType::kHuman || players.second == PlayerType::kHuman) {
    silent = false;
    initscr();
    cbreak();
    noecho();
    keypad(stdscr, TRUE);
  }

  if (silent) {
    int player1_wins = 0; int player2_wins = 0; int draws = 0;
    int winner = PlayGame(players, silent);

    if (winner == 1) { player1_wins += 1; }
    else if (winner == 2) { player2_wins += 1; }
    else if (winner == -1) { draws += 1; }

    std::cout << "Player 1 wins: " << player1_wins << std::endl;
    std::cout << "Player 2 wins: " << player2_wins << std::endl;
    std::cout << "Draws: " << draws << std::endl;
  } else {
    // Play a single game Human vs. AI.
    PlayGame(players, silent); // Inner
  }

  // Wait for any key press.
  if (!silent) {
    getch();
    endwin();
  }

  return 0;
}

// Returns false if the user wants to exit.
bool GetPlayerMove(int board[6][7], int &move) {
  int ch;
  // This function goes inside DrawBoard
  while (true) {
    // User Move
    ch = getch();
    // To play the game, move the right arrow key and the left arrow key around. If you're done, press q
    // Press on the SPACE_BAR to place a piece
    if (ch == KEY_RIGHT && move <= 5) {
      move += 1;
    } else if (ch == KEY_LEFT && move > 0) {
      move -= 1;
    } else if (ch == ' ') {
      return true;
    } else if (ch == 'q') {
        // this is how you quit the game
      return false;
    }
    DrawBoard(board, move); // Inline function.
  }
}

int SwitchPlayer(int player) {
  if (player == 1) {return 2;}
  else if (player == 2) {return 1;}
  else {throw;}
}

int PlayGame(std::pair<PlayerType, PlayerType> players, bool silent) {
  int board[6][7];
  int current_player = 1;
  InitializeBoard(board);
  int player_move = 0;

  // Loop ends if the game ends or GetPlayerMove returns false.
  bool result;
  while (silent == false) {
    DrawBoard(board, player_move);

    PlayerType player_type; // This is calling the struct

    if (current_player == 1) {player_type = players.first;}
    else if (current_player == 2) {player_type = players.second;}

    // avoid updating the GUI
    int move_to_make;

    switch (player_type) {
      case PlayerType::kHuman:
        if (!GetPlayerMove(board, player_move)) {
          printw("Game over.");
          return Winner(board);
        }
        move_to_make = player_move;
        break;
      case PlayerType::kRandom:
        move_to_make = RandomAgent(board, current_player);
        break;
      case PlayerType::kFirst:
        move_to_make = FirstOpenAgent(board, current_player);
        break;
      case PlayerType::kInvalid:
      default:
        throw;
    }
    result = Drop(board, current_player, move_to_make); // Might have to add true or false to Drop.
    if (result == true) {current_player = SwitchPlayer(current_player);}
    else if (result == false) {current_player = SwitchPlayer(current_player);}
    if (Winner(board) == 1) { silent = true;}
    else if (Winner(board) == 2) {silent = true;}
    else if (Winner(board) == -1) {silent = true;}
  }
  int winner = Winner(board);
  if (silent != false) {
    if (winner == 1) {
      printw("Player 1 wins!");
    } else if (winner == 2) {
      printw("Player 2 wins!");
    } else if (winner == -1) {
      printw("Draw.");
    } else {
      printw("Game over.");
    }
  }
  return winner;
}