//***********************************************************
// Filename: DataManager.cs
// Author: Niclas
// Last changes: 08 August 2018
// Content: The DataManager which collects, formats and exports experiment data
//***********************************************************
using System;
using System.Collections;
using System.IO;
using UnityEngine;

//TODO: rewrite class to complement the new StudyDataParser
/// <summary>
/// This class collects data from Events, formats them and exports them into a .csv file
/// </summary>
public class DataManager : MonoBehaviour {
    // Holds all data collected thus far
    private readonly ArrayList expData = new ArrayList();
    // Number of teleports while a specific target is active
    private int currentTeleports = 0;
    // Holds a reference to the GameManager for future use
    private GameManager gManager;
    // Id of the currently active target, doubles as target count, starts with 0 
    private int currentTargetId;
    // Coordinates of the currently active target
    private Vector3 currentTargetPos;
    // Rotation of the currently active target
    private Vector3 currentTargetRot;
    // Distance between the current target and the one before
    private float currentTargetDist = 0;
    // Unique user id in case none gets set
    private string userId = Guid.NewGuid().ToString();
    // Delimiter between items, used to format to .csv 
    private const string Del = ",";


    // Use this for initialization
    void Start() {
        gManager = GetComponentInParent<GameManager>();

        // Register listerners to their event
        TargetSpawnedEvent.RegisterListener(OnTargetSpawned);
        TargetReachedEvent.RegisterListener(OnTargetReached);
        TeleportEvent.RegisterListener(OnTeleport);
        ExperimentEndEvent.RegisterListener(OnExperimentEnd);
    }

    private void OnDestroy() {
        // Unregister listeners from their event
        TargetSpawnedEvent.UnregisterListener(OnTargetSpawned);
        TargetReachedEvent.UnregisterListener(OnTargetReached);
        TeleportEvent.UnregisterListener(OnTeleport);
        ExperimentEndEvent.UnregisterListener(OnExperimentEnd);
    }

    /// <summary>
    /// Listener for TargetSpawnedEvent, extracts information about the current target to variables
    /// </summary>
    /// <param name="tse">The Event, contains its information</param>
    private void OnTargetSpawned(TargetSpawnedEvent tse) {
        currentTargetId = tse.targetId;

        // Distance to spawned target, 0 if startTarget
        currentTargetDist = Vector3.Distance(currentTargetPos, tse.targetTransform.position);

        currentTargetPos = tse.targetTransform.position;
        currentTargetRot = tse.targetTransform.rotation.eulerAngles;
    }

    /// <summary>
    /// Listener for TeleportEvent, adds a row with data about the teleport in expData
    /// </summary>
    /// <param name="te">The Event, contains its information</param>
    private void OnTeleport(TeleportEvent te) {
        if (currentTargetId == 0)
            return;

        currentTeleports++;
        string row = currentTargetId + Del +
            currentTeleports + Del +
            currentTargetPos.x + Del +
            currentTargetPos.z + Del +
            currentTargetRot.y + Del +
            te.startUserPosition.x + Del +
            te.startUserPosition.z + Del +
            te.startUserRotation.y + Del +
            te.startTeleportTime + Del +
            te.endUserPosition.x + Del +
            te.endUserPosition.z + Del +
            te.endUserRotation.y + Del +
            te.endTeleportTime + Del +
            (te.endTeleportTime - te.startTeleportTime) + Del +
            0 + Del +
            Mathf.Sqrt(Mathf.Pow(te.endUserPosition.x - currentTargetPos.x, 2) + Mathf.Pow(te.endUserPosition.z - currentTargetPos.z, 2)) + Del +
            (te.endUserRotation.y - currentTargetRot.y + 180) % 360 + Del +
            currentTargetDist;
        expData.Add(row);
    }
    /// <summary>
    /// Listener for TargetReachedEvent, adds row to expData with data about the reached target and player, ends a teleport chain
    /// </summary>
    /// <param name="tre">The Event, contains its information</param>
    private void OnTargetReached(TargetReachedEvent tre) {
        Debug.Log("Received Target information, id: " + tre.targetId + " time: " + tre.time);
        string row = tre.targetId + Del +
          (-1) + Del +
          tre.targetTransform.position.x + Del +
          tre.targetTransform.position.z + Del +
          tre.targetTransform.rotation.eulerAngles.y + Del +
          0 + Del +
          0 + Del +
          0 + Del +
          0 + Del +
          tre.playerTransform.position.x + Del +
          tre.playerTransform.position.z + Del +
          tre.playerTransform.rotation.eulerAngles.y + Del +
          0 + Del +
          0 + Del +
          0 + Del +
          tre.time + Del +
          Mathf.Sqrt(Mathf.Pow(tre.playerTransform.position.x - tre.targetTransform.position.x, 2) + Mathf.Pow(tre.playerTransform.position.z - tre.targetTransform.position.z, 2)) + Del +
          (tre.targetTransform.rotation.eulerAngles.y - tre.playerTransform.rotation.eulerAngles.y - 180) % 360 + Del +
          currentTargetDist;

        expData.Add(row);

        currentTeleports = 0;
    }

    /// <summary>
    /// Listener for ExperimentEndEvent, sets userID and invokes WriteToFile() to write the .csv file.
    /// Invokes with one second delay to give the last Events time to finish processing
    /// </summary>
    /// <param name="e">The Event, contains its information, however none is required at the moment</param>
    private void OnExperimentEnd(ExperimentEndEvent e) {
        if (gManager.testSubjectId != "") {
            userId = gManager.testSubjectId;
        }
        // Waiting for last TargetReachedEvent to process
        Invoke("WriteToFile", 1);
    }

    /// <summary>
    /// Creates a new .csv file with userID, movement method and date as name.
    /// Writes first row with names of the columns, afterwards each string in expData as new row
    /// </summary>
    private void WriteToFile() {
        string filepath = string.Format(@"{0}-{1}-{2:yyyy-MM-dd_HH-mm-ss}.csv", GetComponentInParent<GameManager>().movementMethod, userId, DateTime.Now);
        using (StreamWriter writer = new StreamWriter(new FileStream(filepath, FileMode.Create, FileAccess.Write))) {
            writer.WriteLine("TargetID, TeleportID, TargetPositionX, TargetPositionZ, TargetRotation, PlayerLastPosX, PlayerLastPosZ, PlayerLastRot, TelStartTime, PlayerPosX, PlayerPosZ, PlayerRotation, TelEndTime, TelDistance, TelTime, TimeNeeded, OffsetPos, OffsetRot, DistTargetToTarget");
            foreach (string row in expData) {
                writer.WriteLine(row);
            }
        }

        Debug.Log("Data written");
    }

}