#include <iostream>
#include <iomanip>
#include <memory>
#include <iterator>
#include <vector>
#include <forward_list>
#include "Room.h"
#include "wordwrap.h"
#include "State.h"
#include "strings.h"
#include <map>
#include "FoodObject.h"
#include <fstream>
#include <sstream>
#include <time.h>

using std::string;
using std::unique_ptr;

string commandBuffer;
State *currentState;

/**
 * Print out the command prompt then read a command into the provided string buffer.
 * @param buffer Pointer to the string buffer to use.
 */
void inputCommand(string *buffer) {
    buffer->clear();
    std::cout << "> ";
    std::getline(std::cin, *buffer);
}

bool LoadFromFile(const std::string& file) {
    std::ifstream ifs(file);
    if (!ifs.is_open()) {
        return false;
    }

    std::string str;
    ifs >> str;
    ifs.close();

    GameObject::game_object_map.clear();
    Room::room_map.clear();

    Packer packer;
    packer.FromHexStr(str);
    {
        size_t objects_size;
        packer.unpack(objects_size);
        for (int i = 0; i < objects_size; i++) {
            int type;
            int id;
            GameObject *obj = nullptr;
            packer.unpack(type);
            packer.unpack(id);
            obj = GameObject::CreateGameObject(static_cast<GameObject::Type>(type), false);
            packer.unpack(*obj);
            GameObject::AddGameObject(obj);
        }
    }

    {
        size_t rooms_size;
        packer.unpack(rooms_size);
        for (int i = 0; i < rooms_size; i++) {
            int id;
            Room *room = new Room();

            packer.unpack(id);
            packer.unpack(*room);
            Room::room_map.insert({id, room});
        }
    }

    packer.unpack(GameObject::game_object_id_counter)
          .unpack(Room::room_id_counter)
          .unpack(State::seed)
          .unpack(*currentState);

    return true;
}

bool SaveToFile(const std::string& file) {
    Packer packer;
    packer.pack(*currentState)
          .pack(State::seed)
          .pack(Room::room_id_counter)
          .pack(GameObject::game_object_id_counter);
    for (const auto& item : Room::room_map) {
        packer.pack(item.second);
        packer.pack(item.first);
    }
    packer.pack(Room::room_map.size());

    for (const auto& item : GameObject::game_object_map) {
        packer.pack(item.second);
        packer.pack(item.first);
        packer.pack(item.second->getObjectType());
    }
    packer.pack(GameObject::game_object_map.size());

    std::ofstream ofs(file, std::ios::trunc | std::ios::out);
    if (!ofs.is_open()) {
        return false;
    }

    ofs << packer.ToHexStr();
    ofs.flush();
    ofs.close();
    return true;
}

void CreateRandomGameObject(Room *room) {
    int cnt = (currentState->NextRandom() % 5) + 1;
    while (cnt--) {
        GameObject::Type type = static_cast<GameObject::Type>(rand() % GameObject::TYPE_MAX_COUNT);
        GameObject *obj = GameObject::CreateGameObject(type);
        GameObject::AddGameObject(obj);

        // use id as keyword
        obj->setKeyword(std::to_string(obj->getGameObjectId()));

        room->AddGameObject(obj->getGameObjectId());

        switch (type) {
            case GameObject::Food: {
                FoodObject *food = dynamic_cast<FoodObject *>(obj);
                food->setName("food");
                food->setEnergy((currentState->NextRandom() % 10 + 1));
                food->setDescription("This is a food. energy: " + std::to_string(food->getEnergy()) + ".");
                break;
            }
            case GameObject::Default: {
                obj->setName("object");
                obj->setDescription("This is an object.");
                break;
            }
            default:
                break;
        }
    }
}

/**
 * Sets up the map.
 */
void initRooms() {
    // Create a map that associates rooms with their corresponding exit directions and adjacent rooms
    std::map<Room *, std::map<std::string, Room *>> roomConnections;

    // Helper function to create a room and add it to the list of rooms in the Room class
    auto createRoom = [&](Room *room, const string &name, const string &desc) {
        room = new Room(&name, &desc);
        Room::addRoom(room);
        // add random game object
        CreateRandomGameObject(room);
        return room;
    };

    Room *r1, *r2, *r3, *r4;

    // Create and initialize room objects
    r1 = createRoom(r1, r1name, r1desc);
    r2 = createRoom(r2, r2name, r2desc);
    r3 = createRoom(r3, r3name, r3desc);
    r4 = createRoom(r4, r4name, r4desc);

    // Associate rooms with adjacent rooms and their corresponding directions
    roomConnections[r1] = {{"north", r2}};
    roomConnections[r2] = {{"south", r1},
                           {"east",  r3}};
    roomConnections[r3] = {{"west",  r2},
                           {"south", r4}};
    roomConnections[r4] = {{"north", r3}};

    // Iterate through the map to set exits for each room
    for (const auto &entry: roomConnections) {
        Room *currentRoom = entry.first;
        const auto &exits = entry.second;

        for (const auto &exit: exits) {
            const string &direction = exit.first;
            Room *connectedRoom = exit.second;

            // Set the respective exit based on the direction
            if (direction == "north") currentRoom->setNorthId(connectedRoom->getRoomId());
            else if (direction == "east") currentRoom->setEastId(connectedRoom->getRoomId());
            else if (direction == "south") currentRoom->setSouthId(connectedRoom->getRoomId());
            else if (direction == "west") currentRoom->setWestId(connectedRoom->getRoomId());
        }
    }
}

/**
 * Sets up the game state.
 */
void initState() {
    currentState = new State(Room::room_map.begin()->first);
}

std::vector<std::string> split(const std::string &str) {
    std::vector<std::string> result;
    std::istringstream iss(str);
    for (std::string s; iss >> s;)
        result.push_back(s);
    return result;
}

/**
 * The main game loop.
 */
void gameLoop() {
    bool gameOver = false;
    auto prev_time = time(nullptr);
    while (!gameOver) {
        /* Ask for a command. */
        bool commandOk = false;
        inputCommand(&commandBuffer);

        auto now = time(nullptr);
        if (now - prev_time > 60) {
            int hp_offset = (now - prev_time) / 60;
            prev_time += hp_offset * 60;
            currentState->setHP(currentState->getHP() - hp_offset);
        }
        gameOver = gameOver || (currentState->getHP() <= 0);
        if (gameOver) { 
            wrapOut("HP is 0， GameOver!!!");
            wrapEndPara();
            break; 
        }

        wrapOut("Current HP: " + std::to_string(currentState->getHP()));
        wrapEndPara();

        /* The first word of a command would normally be the verb. The first word is the text before the first
         * space, or if there is no space, the whole string. */
        auto endOfVerb = static_cast<uint8_t>(commandBuffer.find(' '));

        /* We could copy the verb to another string but there's no reason to, we'll just compare it in place. */
        /* Command to go north. */
        if ((commandBuffer.compare(0, endOfVerb, "north") == 0) || (commandBuffer.compare(0, endOfVerb, "n") == 0)) {
            commandOk = true; /* Confirm command has been handled */
            /* See if there's a north exit */
            Room *northRoom = currentState->getCurrentRoom()->getNorth();
            if (northRoom == nullptr) { /* there isn't */
                wrapOut(&badExit);      /* Output the "can't go there" message */
                wrapEndPara();
            } else {                    /* There is */
                currentState->goTo(northRoom); /* Update state to that room - this will also describe it */
            }
        }
        /* Command to go east. */
        if ((commandBuffer.compare(0, endOfVerb, "east") == 0) || (commandBuffer.compare(0, endOfVerb, "e") == 0)) {
            commandOk = true;
            Room *eastRoom = currentState->getCurrentRoom()->getEast();
            if (eastRoom == nullptr) {
                wrapOut(&badExit);
                wrapEndPara();
            } else {
                currentState->goTo(eastRoom);
            }
        }

        /* Command to go south. */
        if ((commandBuffer.compare(0, endOfVerb, "south") == 0) || (commandBuffer.compare(0, endOfVerb, "s") == 0)) {
            commandOk = true;
            Room *southRoom = currentState->getCurrentRoom()->getSouth();
            if (southRoom == nullptr) {
                wrapOut(&badExit);
                wrapEndPara();
            } else {
                currentState->goTo(southRoom);
            }
        }

        /* Command to go west. */
        if ((commandBuffer.compare(0, endOfVerb, "west") == 0) || (commandBuffer.compare(0, endOfVerb, "w") == 0)) {
            commandOk = true;
            Room *westRoom = currentState->getCurrentRoom()->getWest();
            if (westRoom == nullptr) {
                wrapOut(&badExit);
                wrapEndPara();
            } else {
                currentState->goTo(westRoom);
            }
        }

        if (commandBuffer.compare(0, endOfVerb, "inventory") == 0) {
            commandOk = true;
            for (auto obj_id : currentState->getInventory()) {
                auto obj = GameObject::getGameObjectById(obj_id);
                wrapOut(obj->getKeyword() + ": " + obj->getName());
                wrapEndPara();
            }
        }

        if (commandBuffer.compare(0, endOfVerb, "hp") == 0) {
            wrapOut("Current HP: " + std::to_string(currentState->getHP()));
            wrapEndPara();
            commandOk = true;
        }

        // check get <keyword>, drop <keyword>, eat <keyword>
        if (!commandOk) {
            std::vector<std::string> words = split(commandBuffer);
            int id = words.size() >= 2 ? std::strtol(words[1].c_str(), nullptr, 10) : 0;

            if (words.size() >= 2 && words[0].compare("load") == 0) {
                commandOk = true;
                if (!LoadFromFile(words[1])) {
                    wrapOut(&loadGameFail);
                } else {
                    wrapOut(&loadGameSuccess);
                }
                wrapEndPara();
            }

            if (words.size() >= 2 && words[0].compare("save") == 0) {
                commandOk = true;
                if (!SaveToFile(words[1])) {
                    wrapOut(&saveGameFail);
                } else {
                    wrapOut(&saveGameSuccess);
                }
                wrapEndPara();
            }

            if (id > 0 && words[0].compare("get") == 0) {
                commandOk = true;
                if (currentState->IsInInventory(id)) {
                    wrapOut(&itemInInventory);
                    wrapEndPara();
                } else if (!currentState->getCurrentRoom()->IsInRoom(id)) {
                    wrapOut(&itemNotFound);
                    wrapEndPara();
                } else {
                    currentState->getCurrentRoom()->RemoveGameObject(id);
                    currentState->addToInventory(id);
                    wrapOut(itemGot + GameObject::getGameObjectById(id)->getName());
                    wrapEndPara();
                }
            }

            if (id > 0 && words[0].compare("drop") == 0) {
                commandOk = true;
                if (currentState->getCurrentRoom()->IsInRoom(id)) {
                    wrapOut(&itemInRoom);
                    wrapEndPara();
                } else if (!currentState->IsInInventory(id)) {
                    wrapOut(&itemNotFound);
                    wrapEndPara();
                } else {
                    currentState->removeFromInventory(id);
                    currentState->getCurrentRoom()->AddGameObject(id);
                    wrapOut(itemDropped + GameObject::getGameObjectById(id)->getName());
                    wrapEndPara();
                }
            }

            if (id > 0 && words[0].compare("eat") == 0) {
                commandOk = true;
                if (!currentState->IsInInventory(id)) {
                    wrapOut(&itemNotFound);
                    wrapEndPara();
                } else {
                    GameObject *obj = GameObject::getGameObjectById(id);
                    if (obj->getObjectType() != GameObject::Food) {
                        wrapOut(&itemNotFound);
                        wrapEndPara();
                    } else {
                        FoodObject *food = dynamic_cast<FoodObject *>(obj);
                        currentState->setHP(currentState->getHP() + food->getEnergy());
                        currentState->removeFromInventory(id);
                        wrapOut(itemEaten + GameObject::getGameObjectById(id)->getName());
                        wrapOut("Current HP: " + std::to_string(currentState->getHP()));
                        wrapEndPara();
                    }
                }
            }

            if (id > 0 && words[0].compare("examine") == 0) {
                commandOk = true;
                if (!currentState->IsInInventory(id) && !currentState->getCurrentRoom()->IsInRoom(id)) {
                    wrapOut(&itemNotFound);
                    wrapEndPara();
                } else {
                    wrapOut(GameObject::getGameObjectById(id)->getDescription());
                    wrapEndPara();
                }
            }
        }

        /* Quit command */
        if ((commandBuffer.compare(0, endOfVerb, "quit") == 0)) {
            commandOk = true;
            gameOver = true;
        }

        /* If commandOk hasn't been set, command wasn't understood, display error message */
        if (!commandOk) {
            wrapOut(&badCommand);
            wrapEndPara();
        }

    }
}


int main() {
    initWordWrap();
    initRooms();
    initState();
    currentState->announceLoc();
    gameLoop();
    return 0;
}