package com.example.schedulerapp;

import java.net.*;
import java.io.*;
import java.time.LocalDate;
import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;
import java.util.ArrayList;
import java.util.concurrent.TimeUnit;

public class Model {
    private PrintWriter writer;
    private Socket socket;
    protected ArrayList<String> shifts;
    protected ArrayList<String> employees;
    protected ArrayList<ModelSubscriber> subscribers;

    static LocalDate date;
    private boolean isManager;
    private int thisEmployee;
    private int selectedEmployee;

    public Model(String hostname, int port) {
        selectedEmployee = 1;   //testing
        subscribers = new ArrayList<>();
        if(date == null) {
            date = LocalDate.now();
        }
        isManager = false;          // changes if manager logs in
        this.shifts =  new ArrayList<>();
        this.employees = new ArrayList<>();
        try {
            InetAddress ip = InetAddress.getByName(hostname);
            this.socket = new Socket(ip, port);
            System.out.println("Connected to the scheduling server");

            new ReceiveThread(this.socket, this).start();

            OutputStream output = this.socket.getOutputStream();
            this.writer = new PrintWriter(output, true);

        } catch (UnknownHostException error) {
            System.out.println("Server not found: " + error.getMessage());
        } catch (IOException error) {
            System.out.println("I/O Error: " + error.getMessage());
        }
    }

    public void setIsManager(boolean aBool){
        isManager = aBool;
    }

    public boolean getIsManager(){
        return isManager;
    }

    public void setThisEmployee(int id){
        thisEmployee = selectedEmployee = id;
    }

    public int getThisEmployee(){
        return thisEmployee;
    }

    //for manager only, allows viewing of weekly schedule by employee
    public void setSelectedEmployee(int id){
        selectedEmployee = id;
        notifySubscribers();
    }

    public int getSelectedEmployee(){
        return selectedEmployee;
    }

    public void dateNext(){
        date = date.plusDays(1);
        notifySubscribers();
    }

    public void datePrev(){
        date = date.minusDays(1);
        notifySubscribers();
    }

    //todo: add calender to fill jump field
    public void dateJump(LocalDate date){
        this.date = date;
        notifySubscribers();
    }

    //todo
    //Return
    void getAllEmployees() {

    }

    void updateAllShifts(){
        writer.println("allShifts");
    }

    void updateAllEmployees(){
        writer.println("allEmployees");
    }

    void addEmployee(String first_name, String last_name) {
        writer.println("addEmployee/" + first_name + "/" + last_name);
    }

    void removeEmployee(String employeeID) {
        writer.println("removeEmployee/" + employeeID);
    }

    void printAllEmployees(){
        System.out.println(this.employees);
    }

    String getEmployeeByID(int id) {
        if (!this.employees.isEmpty()) {
            for(String e: this.employees){
                if(!e.equals("allEmployees")){
                    String[] eSplit = e.split("\\.");
                    try {
                        if(Integer.parseInt(eSplit[0]) == id){
                            return eSplit[1] + " " + eSplit[2];
                        }
                    } catch (NumberFormatException exception){
                        System.out.println("getEmployeeByID: string cannot be integer parsed");
                    }

                }
            }
            return "No Employee with that ID";
        }
        return "No Employees";
    }

    void addShift(int id, String date, int start, int end){
        writer.println("addShift/"+id+"/"+date+"/"+start+"/"+end);
        notifySubscribers();
    }

    void removeShift(int shiftID){
        writer.println("removeShift/"+shiftID);
        notifySubscribers();
    }

    void editShift(int shiftID, String day, int start, int end) {
        writer.println("editShift/"+shiftID+"/"+day+"/"+start+"/"+end);
        notifySubscribers();
    }

    void printAllShifts() {
        System.out.println(this.shifts);
    }

    /*
    Parameters:
        - String date in format 2022-03-10.
    Return: ArrayList<String> where each string is a shift of format id.yyyy-mm-dd.start.end
    */
    ArrayList<String> getShiftsByDay(String date){
        String[] split = date.split("-");
        ArrayList<String> output = new ArrayList<>();
        for(String shift: this.shifts){
            if(!shift.equals("allShifts")){
                String[] shiftSplit = shift.split("\\.");
                String[] dateSplit = shiftSplit[1].split("-");
                try {
                    if(Integer.parseInt(split[0]) == Integer.parseInt(dateSplit[0]) &&
                            Integer.parseInt(split[1]) == Integer.parseInt(dateSplit[1]) &&
                            Integer.parseInt(split[2]) == Integer.parseInt(dateSplit[2])){
                        output.add(shift);
                    }
                } catch (Exception e){
                    System.out.println("Error: Parsing string to int");
                }
            }
        }
        return output;
    }

    /*
    Parameters:
        startOfWeek - The first day of the week in "yyyy-mm-dd" format
        endOfWeek - The last day of the week in "yyyy-mm-dd" format
    Return: ArrayList<String>
     */
    ArrayList<String> getShiftsByWeek(String startOfWeek, String endOfWeek){
        String[] startSplit = startOfWeek.split("-");
        String[] endSplit = endOfWeek.split("-");
        ArrayList<String> output = new ArrayList<>();
        for(String shift: this.shifts){
            if(!shift.equals("allShifts")){
                String[] shiftSplit = shift.split("\\.");
                String[] dateSplit = shiftSplit[1].split("-");
                try {
                    if(Integer.parseInt(startSplit[0]) >= Integer.parseInt(dateSplit[0]) &&
                            Integer.parseInt(startSplit[1]) >= Integer.parseInt(dateSplit[1]) &&
                            Integer.parseInt(startSplit[2]) >= Integer.parseInt(dateSplit[2])){
                        if(Integer.parseInt(endSplit[0]) >= Integer.parseInt(dateSplit[0]) &&
                                Integer.parseInt(endSplit[1]) >= Integer.parseInt(dateSplit[1]) &&
                                Integer.parseInt(endSplit[2]) >= Integer.parseInt(dateSplit[2])){
                            output.add(shift);
                        }

                    }
                } catch (Exception e){
                    System.out.println("Error: Parsing string to int");
                }
            }
        }
        return output;
    }

    //for view
    public ArrayList<Shift> getWeeklySchedule(){
        String start;
        String end;
        // get start and end dates to pass along
        int today = date.getDayOfWeek().getValue();     // Mon is 1, Sun is 7
        if (today == 7) {   //this is the start date
            start = date.toString();
            end = date.plusDays(6).toString();
        }
        else {
            start = date.minusDays(today).toString();
            end = date.plusDays(6 - today).toString();
        }
        printAllShifts();
        System.out.println("start: " + start + " end: " + end + " shifts returned " + getShiftsByWeek(start, end).size());

        return convertToShift(getShiftsByWeek(start, end));
    }

    //for view
    public ArrayList<Shift> getDailySchedule(){
        return convertToShift(getShiftsByDay(date.toString()));
    }

    //format id.yyyy-mm-dd.start.end
    //convert ArrayList<String> to ArrayList<Shift>
    protected ArrayList<Shift> convertToShift(ArrayList<String> input){
        DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-ddHHmm");
        ArrayList<Shift> output = new ArrayList<>();
        for (String dbShift : input){
            String[] strings = dbShift.split("\\.");
            int id = Integer.parseInt(strings[0]);
            if (strings[2].length() == 3) strings[2] = "0" + strings[2];
            if (strings[3].length() == 3) strings[3] = "0" + strings[3];
            LocalDateTime start = LocalDateTime.parse(strings[1] + strings[2], formatter);
            LocalDateTime end = LocalDateTime.parse(strings[1] + strings[3], formatter);
            output.add(new Shift(id, start, end));
        }
        return output;
    }

    ArrayList<String> getEmployeeShifts(String id){
        ArrayList<String> output = new ArrayList<>();
        for(String shift: this.shifts){
            String[] shiftSplit = shift.split("\\.");
            if (shiftSplit[0].equals(id)) {
                output.add(shift);
            }
        }
        return output;
    }

    //todo
    void getEmployeeShiftsByWeek(){
    }

    void logOut() {
        writer.println("logout");
        try {
            this.socket.close();
        } catch (IOException ex){
            System.out.println("Error: Failed to close socket");
        }
    }

    public static void main(String[] args) {
        String hostname = "localhost";  //"localhost if connecting to local server, or "172.16.1.99" connecting to Rafi's server
        int port = 8989; //Rafi's server port is 8989
        Model client = new Model(hostname, port);
        System.out.print("Retrieving Data");
        while(client.employees.isEmpty() && client.shifts.isEmpty()){
            System.out.print(".");
            try {
                TimeUnit.SECONDS.sleep(1);
            } catch (InterruptedException e) {
                System.out.println("Error: ScheduleClient main. Interrupted while retrieving data ");
            }
        }
        System.out.println();
        System.out.println("Data retrieved.");
        System.out.println("ScheduleClient is ready to use!");
    }


    public ArrayList<String> returnFormattedEmployeeNames(){
        ArrayList<String> result = new ArrayList<>();
        ArrayList<String> temp = (ArrayList<String>) this.employees.clone();
        String tempName = "";
        temp.remove(0);
        for(int i = 0; i < temp.size(); i++){
            String[] templist = temp.get(i).split("\\.");
            for(int j =0; j < 3; j++){
                if(j == 1 || j == 2){
                    tempName += templist[j];
                }
                if(j == 1){
                    tempName += " ";
                }
            }
            result.add(tempName);
            tempName = "";
        }
        System.out.println(result);
        return result;
    }

    public int getIDbyIndex(int index) {
        ArrayList tempList = (ArrayList) this.employees.clone();
        String tempEmployee = (String) tempList.get(index + 1);
        String[] splitString = tempEmployee.split("\\.");
        return Integer.parseInt(splitString[0]);
    }

    //for publish/subscribe
    public void addSubscriber(ModelSubscriber sub){
        subscribers.add(sub);
    }

    public void notifySubscribers(){
        for (ModelSubscriber sub : subscribers){
            sub.modelChanged();
        }
    }
}