using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using System;
using System.IO;
using System.Globalization;

namespace CSVReader
{
    public class EventCSVReader
    {
        private string completeFileName;
        private char separator = ';';
        private long lastLength = 0;

        public EventCSVReader(string filename)
        {
            completeFileName = Path.Combine(".", "Assets", "CSVInput", filename);
            if (!File.Exists(completeFileName))
            {
                completeFileName = "Err";
                Debug.Log("Unable to find Event File " + filename);
            }
        }

        /// <summary>
        /// Reads the entire File that has been found when Constructing the class instance. No streams are left open after the use of this method.
        /// If instance construction was not successfull, only return null.
        /// </summary>
        /// <returns>
        /// Returns a field of EventObjects including all entries of the file
        /// </returns>
        public EventObject[] ReadFile()
        {
            if (completeFileName == "Err")
            {
                return null;
            }
            List<string> lines = new List<string>();
            try
            {
                using (StreamReader fs = new StreamReader(File.Open(completeFileName, FileMode.Open, FileAccess.Read, FileShare.ReadWrite)))
                {
                    if (fs.BaseStream.Length == lastLength)
                    {
                        return new EventObject[0];
                    }
                    lastLength = fs.BaseStream.Length;
                    string line;
                    while ((line = fs.ReadLine()) != null)
                        lines.Add(line);
                }
            }
            catch
            {
                Debug.Log("Unable to Read Lines from Event File");
                return null;
            }
            EventObject[] events = new EventObject[lines.Count];
            for (int i = 0; i < lines.Count; i++)
            {
                string[] elems = lines[i].Split(separator);
                if (elems.Length == 6)
                {
                    try
                    {
                        events[i] = new EventObject(int.Parse(elems[0]),
                            double.Parse(elems[1].Replace(',', '.'), CultureInfo.InvariantCulture),
                            float.Parse(elems[2].Replace(',', '.'), CultureInfo.InvariantCulture),
                            float.Parse(elems[3].Replace(',', '.'), CultureInfo.InvariantCulture),
                            float.Parse(elems[4].Replace(',', '.'), CultureInfo.InvariantCulture),
                            (EventType)int.Parse(elems[5]));
                    }
                    catch (Exception e)
                    {
                        Debug.Log("Eventfile Error \"" + e.Message + "\" at line " + i);
                        events[i] = null;
                    }
                }
                else if (elems.Length == 7)
                {
                    try
                    {
                        events[i] = new EventObject(int.Parse(elems[0]),
                            double.Parse(elems[1].Replace(',', '.'), CultureInfo.InvariantCulture),
                            float.Parse(elems[3].Replace(',', '.'), CultureInfo.InvariantCulture),
                            float.Parse(elems[4].Replace(',', '.'), CultureInfo.InvariantCulture),
                            float.Parse(elems[5].Replace(',', '.'), CultureInfo.InvariantCulture),
                            (EventType)int.Parse(elems[6]));
                        events[i].TimestampEnd = double.Parse(elems[2].Replace(',', '.'), CultureInfo.InvariantCulture);
                    }
                    catch (Exception e)
                    {
                        Debug.Log("Eventfile Error \"" + e.Message + "\" at line " + i);
                        events[i] = null;
                    }
                }
                else if (elems.Length == 9)
                {
                    try
                    {
                        events[i] = new EventObject(int.Parse(elems[0]),
                            double.Parse(elems[1].Replace(',', '.'), CultureInfo.InvariantCulture),
                            float.Parse(elems[2].Replace(',', '.'), CultureInfo.InvariantCulture),
                            float.Parse(elems[3].Replace(',', '.'), CultureInfo.InvariantCulture),
                            float.Parse(elems[4].Replace(',', '.'), CultureInfo.InvariantCulture),
                            (EventType)int.Parse(elems[8]));
                        events[i].setIdealViewingPosition(float.Parse(elems[5].Replace(',', '.'), CultureInfo.InvariantCulture),
                            float.Parse(elems[6].Replace(',', '.'), CultureInfo.InvariantCulture),
                            float.Parse(elems[7].Replace(',', '.'), CultureInfo.InvariantCulture));
                    }
                    catch (Exception e)
                    {
                        Debug.Log("Eventfile Error \"" + e.Message + "\" at line " + i);
                        events[i] = null;
                    }
                }
                else if (elems.Length == 10)
                {
                    try
                    {
                        events[i] = new EventObject(int.Parse(elems[0]),
                            double.Parse(elems[1].Replace(',', '.'), CultureInfo.InvariantCulture),
                            float.Parse(elems[3].Replace(',', '.'), CultureInfo.InvariantCulture),
                            float.Parse(elems[4].Replace(',', '.'), CultureInfo.InvariantCulture),
                            float.Parse(elems[5].Replace(',', '.'), CultureInfo.InvariantCulture),
                            (EventType)int.Parse(elems[9]));
                        events[i].setIdealViewingPosition(float.Parse(elems[6].Replace(',', '.'), CultureInfo.InvariantCulture),
                            float.Parse(elems[7].Replace(',', '.'), CultureInfo.InvariantCulture),
                            float.Parse(elems[8].Replace(',', '.'), CultureInfo.InvariantCulture));
                        events[i].TimestampEnd = double.Parse(elems[2].Replace(',', '.'), CultureInfo.InvariantCulture);
                    }
                    catch (Exception e)
                    {
                        Debug.Log("Eventfile Error \"" + e.Message + "\" at line " + i);
                        events[i] = null;
                    }
                }
                else
                {
                    Debug.Log("Unclear length of line " + i);
                    events[i] = null;
                }
            }
            return events;
        }
    }
}