// GameState.cpp
#include <iostream>
#include <stdexcept>
#include <SFML/Graphics.hpp>
#include "botinterface.hpp"
#include "common.hpp"
#include "playerinterface.hpp"
#include "gamestate.hpp"

namespace snakeplusplus
{
    GameEngine::GameEngine()
    {
        InitializeGenerator();
        return;
    }

    void GameEngine::Start()
    {
        PrepareGameBoard();
        graphics.StartGameWindow();
        Loop();
        return;
    }

    void GameEngine::Reset()
    {
        AddIteration();
        player.Reset();
        if (isBotControlled) { while (!bot.path.empty()) { bot.path.pop(); } }
        PrepareGameBoard();
        isGameOver = false;
        return;
    }

    void GameEngine::AddIteration(void) 
    {
        graphics.CheckContinue(isBotControlled);
        if (player.body.size() > 40) 
        {
            UpdateAverage();
            double adjustmentAmount = 0.002;
            if (average > player.body.size()) { bot.AdjustProbability(adjustmentAmount); }
            else { bot.AdjustProbability(-adjustmentAmount); }
        }
        std::cout << "[Info - GameEngine] Current average: " << average << std::endl;
        std::cout << "[Info - GameEngine] Previous iteration size: " << player.body.size() << std::endl;

    }

    void GameEngine::Loop(void)
    {
        int currentScore = 0;
        while (graphics.IsOpen())
        {
            if (isGameOver) { Reset(); }
            UpdatePlayerSpeed();
            PlaceNewSnakePart(MovePlayer());
            RegenerateFood();
            currentScore = player.body.size() * 100;
            //bot.UpdateProbability(player.body.size());
            //graphics.DisplayGameState(gameBoard, currentScore);
        }
        return;
    }

    sf::Vector2f GameEngine::MovePlayer(void)
    {
        return sf::Vector2f(player.headLocation.x + player.speed.x, player.headLocation.y + player.speed.y);
    }


    sf::Vector2f GameEngine::GetGameBoundaries(void)
    {
        return graphics.gameBoundaries;
    }

    void GameEngine::PlaceNewSnakePart(sf::Vector2f location) {
        if (!player.speed.x && !player.speed.y) { return; }
        try {
            char* locationState = &gameBoard.at(location.y).at(location.x);
            if (*locationState == 'O' && (player.body.size() > 1)) {
                isGameOver = true; // Game should end (Snake touching snake)
            }
            *locationState = 'O';
            player.body.push(locationState);
            player.headLocation = location;
            if (playerFood.location != location)
                player.Pop();
        } catch (const std::out_of_range& error) {
            isGameOver = true; // Snake ran into edge
        }
        return;
    }


    // Generates new food until not colliding with player
    void GameEngine::RegenerateFood()
    {
        // Generate a new food location if the current one is occupied
        while (gameBoard.at(playerFood.location.y).at(playerFood.location.x) == 'O') {
            playerFood.GenerateNewFood(GetGameBoundaries());
        }

        // Update the game board with the new food location
        gameBoard.at(playerFood.location.y).at(playerFood.location.x) = 'X';
    }


    void GameEngine::PrepareGameBoard(void)
    {
        gameBoard.clear();
        sf::Vector2f boardDimensions = GetGameBoundaries();
        gameBoard.resize(boardDimensions.y, std::vector<char> (boardDimensions.x, ' '));
        // Snake setup
        player.headLocation.x = GenerateRandomNumber(boardDimensions.x);
        player.headLocation.y = GenerateRandomNumber(boardDimensions.y);
        {
            char* locationState = &gameBoard.at(player.headLocation.y).at(player.headLocation.x);
            player.body.push(locationState);
            *locationState = 'O';
        }
        // Food setup
        playerFood.GenerateNewFood(boardDimensions);
        gameBoard.at(playerFood.location.y).at(playerFood.location.x) = 'X';
        return;
    }

    void GameEngine::UpdatePlayerSpeed(void)
    {
        PlayerDirection controller;
        if (isBotControlled) { 
            if (bot.path.empty()) { 
                bot.GetNewPath(gameBoard, player.headLocation, GetGameBoundaries(), player.body.size()); 
            }
            controller = bot.GetInput(&player.headLocation); 
        }
        else { controller = GetPlayerInput(); }
        switch (controller) { 
            case kUp:
                if (player.speed.y == kUnitSpeed) { break; }
                player.speed.x = 0;
                player.speed.y = -kUnitSpeed;
                break;
            case kLeft:
                if (player.speed.x == kUnitSpeed) { break; }
                player.speed.x = -kUnitSpeed;
                player.speed.y = 0;
                break;
            case kRight:
                if (player.speed.x == -kUnitSpeed) { break; }
                player.speed.x = kUnitSpeed;
                player.speed.y = 0;
                break;
            case kDown:
                if (player.speed.y == -kUnitSpeed) { break; }
                player.speed.x = 0;
                player.speed.y = kUnitSpeed;
                break;
            default:
                break;
        }
        return;
    }
    void GameEngine::UpdateAverage() {
        totalLength += player.body.size();
        amountPlayed += 1;
        average = (double)totalLength / amountPlayed;
    }
}