using DigitalRuby.Tween;
using System;
using System.Collections;
using System.Linq;
using TMPro;
using UnityEngine;
using UnityEngine.UI;
using UnityEngine.Video;

/// <summary>
/// TemplateCourse scene manager
/// </summary>
public class CoursesController : AbstractFeedback
{
    public TMP_Text courseTitle;

    /// <summary>
    /// The current user
    /// </summary>
    private User user;

    /// <summary>
    /// Current user progress for this course
    /// </summary>
    private PersistentDataController.SavedCourseProgress progress = null;

    /// <summary>
    /// ScriptableObject with list of all courses
    /// </summary>
    public CourseList courselist;

    /// <summary>
    /// Reference to Course ScriptableObject
    /// </summary>
    private Course course;

    /// <summary>
    /// Index of the current word/letter in the course.learnables list
    /// </summary>
    private int currentWordIndex = 0;

    /// <summary>
    /// This holds the amount of words in the course
    /// </summary>
    private int maxWords;

    /// <summary>
    /// Number of correct words so far
    /// (can be modified to a list or something like that to give better feedback)
    /// </summary>
    private int correctWords = 0;

    /// <summary>
    /// The "finished" screen
    /// </summary>
    public GameObject ResultPanel;

    /// <summary>
    /// Reference to the title on the results panel
    /// </summary>
    public TMP_Text ResultsTitle;

    /// <summary>
    /// Reference to the description on the results panel
    /// </summary>
    public TMP_Text ResultsDecription;

    /// <summary>
    /// Button to go back to courses list
    /// </summary>
    public Button CoursesButton;

    /// <summary>
    /// DateTime containint the start moment
    /// </summary>
    private DateTime startMoment;

    /// <summary>
    /// Reference to the timeSpent UI
    /// </summary>
    public TMP_Text timeSpent;

    /// <summary>
    /// Reference to the feedback field
    /// </summary>
    private TMP_Text feedbackText;

    /// <summary>
    /// Reference to the progress bar
    /// </summary>
    private Slider feedbackProgress;

    /// <summary>
    /// Reference to the progress bar image, so we can add fancy colors
    /// </summary>
    private Image feedbackProgressImage;

    public VideoPlayer videoPlayer;

    /// <summary>
    /// Timer to keep track of how long a incorrect sign is performed
    /// </summary>
    protected DateTime timer;

    /// <summary>
    /// Current predicted sign
    /// </summary>
    protected string predictedSign = null;

    /// <summary>
    /// Previous incorrect sign, so we can keep track whether the user is wrong or the user is still changing signs
    /// </summary>
    protected string previousIncorrectSign = null;

    public Animator confettiAnimation;
    public GameObject panelSignWithVideoAndImagePrefab;
    public GameObject panelSignWithImagePrefab;
    public GameObject panelMultipleChoicePrefab;
    public Transform canvas;
    private GameObject previousPanel = null;

    /// <summary>
    /// This function is called when the script is initialised.
    /// It inactivatis the popup, finds a webcam to use and links it via the WebcamTexture to the display RawImage.
    /// It takes the correct course from the courselist, using the courseIndex.
    /// Then it checks whether or not the User has started the course yet, to possibly create a new progress atribute for the course.
    /// Then it sets up the course-screen to display relevant information from the course-scriptable.
    /// </summary>
    void Start()
    {
        StartCourseController();
        signPredictor.SetModel(course.theme.modelIndex);
        AddSelfAsListener();
    }

    /// <summary>
    /// Holds the course-specific logic to start the controller, it is seperated to allow the course to be reset (if that would become needed)
    /// </summary>
    public void StartCourseController()
    {
        // Setting up course
        course = courselist.courses[courselist.currentCourseIndex];
        maxWords = course.theme.learnables.Count;

        // Create entry in current user for keeping track of progress
        //PersistentDataController pdc = PersistentDataController.GetInstance();
        //pdc.Load();
        user = UserList.GetCurrentUser();
        progress = user.GetCourseProgress(course.index);
        if (progress == null)
        {
            progress = new PersistentDataController.SavedCourseProgress();
            progress.courseIndex = course.index;
            user.AddCourseProgress(progress);
        }
        UserList.Save();
        courseTitle.text = course.title;

        currentWordIndex = 0;
        previousPanel = SetupPanel();

        // Hide the result panel
        ResultPanel.SetActive(false);
        // Set the startTime
        startMoment = DateTime.Now;
    }

    private Tuple<int, int> FetchSign()
    {
        // TODO: @Tibe here you need to provide other signs and there question method

        /**************************
         * TODO: @Tibe
         * 
         * In deze functie beslist welk panel je nu nodig hebt
         * Momenteel doe ik gwn iets om te wisselen tussen de twee (moet zeker weg want je begint ALTIJD met een imageANDvideo
         * 
         * Je ziet zelf maar hoe groot je de sets van woorden maakt, om de 5 ofzo
         * Altijd eerst video and image, nadien kan je afwisselen, mag random
         * 
         * ALSO:
         * Hiervoor moet ge bij Dries zijn, maar man is verdwenen. (100 jaar gingen voorbij en mijn broer en ik vonden een nieuwe oorzaak voor hoofdpijn)
         * Progress gaat ook aangepast moeten worden, als een user terugkeert tijdens een course en later hervat ga je moeten weten welke set die zat
         * Zeker als ge woorden in een andere volgorde zou willen doen, gaat ge echt nog aan uw 40u geraken :)
         * --> dat gaat bijgehouden worden in een van die user files. (Stalk Dries indien nodig, voor andere zaken kan je mij ook vragen stellen)
         * 
         * *************************/

        int panelChosen = currentWordIndex % 2 + 1;
        return Tuple.Create(currentWordIndex, panelChosen);
    }

    /// <summary>
    /// This function is called when the next-sign button is pressed.
    /// It increased the wordindex and fetches new videos/images if index<max, because then the coure is not fincished yet.
    /// If the maximum is reached, finishcourse is called to save the "finished" progress to the user.
    /// </summary>
    public void NextSign()
    {
        // If the currentindex >= maxwords, it indicated that the course is already finished, running the next code is the meaningless.
        if (currentWordIndex >= maxWords) { return; }

        confettiAnimation.SetTrigger("Display Confetti");

        // Goto the next word/letter
        currentWordIndex++;

        // TODO: fix correct word count
        correctWords++;
        progress.progress = (float)correctWords / (float)maxWords;
        UserList.Save();

        // Update UI if course is not finished yet
        if (currentWordIndex < maxWords)
        {
            // Set next sign/video/image
            StartCoroutine(CRNextSign());
        }
        // Finish course and record progress
        else
        {
            FinishCourse();
        }
    }

    private IEnumerator CRNextSign()
    {
        GameObject newPanel = SetupPanel();
        previousPanel.transform.SetAsFirstSibling();
        newPanel.GetComponent<Animator>().SetTrigger("Slide Panel");

        yield return new WaitForSeconds(1.0f);

        confettiAnimation.ResetTrigger("Display Confetti");
        GameObject.Destroy(previousPanel);
        previousPanel = newPanel;
    }

    private GameObject SetupPanel()
    {
        int panelId;
        (currentWordIndex, panelId) = FetchSign().ToValueTuple();
        switch (panelId)
        {
            case 0: return null; // TODO: @Tibe multiple choice setup
                /**************************
                 * TODO: @Tibe
                 * 
                 * Hier moet de panelMultipleChoice worden aangemaakt
                 * Geef publieke dingen mee aan uw script.
                 * Kan je eventueel zelf aanpassen,
                 * naargelang hoe je het wilt implementeren 
                 * 
                 * *************************/
            case 1:
                {
                    GameObject panel = GameObject.Instantiate(panelSignWithImagePrefab, canvas);
                    panel.transform.SetAsFirstSibling();

                    PanelWithImage script = panel.GetComponent<PanelWithImage>();
                    script.signs = course.theme.learnables;
                    script.currentSignIndex = currentWordIndex;
                    script.isPreview = (course.theme.modelIndex == ModelIndex.NONE);
                    feedbackProgress = script.feedbackProgressBar;
                    feedbackProgressImage = script.feedbackProgressImage;
                    feedbackText = script.feedbackText;
                    script.Display();
                    signPredictor.SwapScreen(script.webcamScreen);
                    return panel;
                }
            case 2:
                {
                    GameObject panel = GameObject.Instantiate(panelSignWithVideoAndImagePrefab, canvas);
                    panel.transform.SetAsFirstSibling();

                    PanelWithVideoAndImage script = panel.GetComponent<PanelWithVideoAndImage>();
                    script.signs = course.theme.learnables;
                    script.currentSignIndex = currentWordIndex;
                    script.isPreview = (course.theme.modelIndex == ModelIndex.NONE);
                    script.videoPlayer = videoPlayer;
                    feedbackProgress = script.feedbackProgressBar;
                    feedbackProgressImage = script.feedbackProgressImage;
                    feedbackText = script.feedbackText;
                    script.Display();
                    signPredictor.SwapScreen(script.webcamScreen);
                    return panel;
                }
        }
        return null;
    }

    /// <summary>
    /// finishcourse is called to save the "finished" progress to the user.
    /// </summary>
    public void FinishCourse()
    {
        // Show the "finished" screen
        ResultPanel.SetActive(true);

        // Set the correct title
        ResultsTitle.text = course.title + " voltooid!";

        // Set the correct description
        ResultsDecription.text = "Goed gedaan! Je kan nu spelletjes spelen met " + course.title + " om verder te oefenen!";

        // Set the total time spent UI
        TimeSpan time = DateTime.Now - startMoment;
        timeSpent.text = time.ToString(@"hh\:mm\:ss");

        // Link button
        CoursesButton.onClick.AddListener(() => { SystemController.GetInstance().BackToPreviousScene(); });

        progress.progress = 1.0f;
        UserList.Save();
    }

    /// <summary>
    /// The updateFunction that is called when new probabilities become available
    /// </summary>
    /// <returns></returns>
    protected override IEnumerator UpdateFeedback()
    {
        if (currentWordIndex < course.theme.learnables.Count)
        {
            // Get current sign
            Learnable sign = course.theme.learnables[currentWordIndex];
            string currentSign = sign.name;

            // Get the predicted sign
            if (signPredictor != null && signPredictor.learnableProbabilities != null &&
                currentSign != null && signPredictor.learnableProbabilities.ContainsKey(currentSign))
            {
                float accCurrentSign = signPredictor.learnableProbabilities[currentSign];

                // Get highest predicted sign
                string predictedSign = signPredictor.learnableProbabilities.Aggregate((a, b) => a.Value > b.Value ? a : b).Key;
                float accPredictSign = signPredictor.learnableProbabilities[predictedSign];
                Learnable predSign = course.theme.learnables.Find(l => l.name == predictedSign);

                if (feedbackText != null && feedbackProgressImage != null)
                {
                    Color col;
                    if (accCurrentSign > sign.thresholdPercentage)
                    {
                        feedbackText.text = "Goed";
                        col = new Color(0x8b / 255.0f, 0xd4 / 255.0f, 0x5e / 255.0f);
                    }
                    else if (accCurrentSign > 0.9 * sign.thresholdPercentage)
                    {
                        feedbackText.text = "Bijna";
                        col = new Color(0xf2 / 255.0f, 0x7f / 255.0f, 0x0c / 255.0f);
                    }
                    else if (accPredictSign > predSign.thresholdPercentage)
                    {
                        feedbackText.text = $"Verkeerde gebaar: '{predictedSign}'";
                        col = new Color(0xf5 / 255.0f, 0x49 / 255.0f, 0x3d / 255.0f);
                        accCurrentSign = 0.0f;
                    }
                    else
                    {
                        feedbackText.text = $"Detecteren ...";
                        col = new Color(0xf5 / 255.0f, 0x49 / 255.0f, 0x3d / 255.0f);
                        //accCurrentSign = 0.0f;
                    }

                    feedbackText.color = col;
                    feedbackProgressImage.color = col;

                    float oldValue = feedbackProgress.value;
                    // use an exponential scale 
                    float newValue = Mathf.Exp(4 * (accCurrentSign - 1.0f));
                    feedbackProgress.gameObject.Tween("FeedbackUpdate", oldValue, newValue, 0.2f, TweenScaleFunctions.CubicEaseInOut, (t) =>
                    {
                        if (feedbackProgress != null)
                        {
                            feedbackProgress.value = t.CurrentValue;
                        }
                    });
                }

                if (accPredictSign > sign.thresholdPercentage)
                {
                    // Correct sign
                    if (predictedSign == currentSign)
                    {
                        yield return new WaitForSeconds(1.0f);
                        NextSignIfCorrect(currentSign, predictedSign);
                        timer = DateTime.Now;
                        previousIncorrectSign = null;
                        predictedSign = null;
                    }
                    // Incorrect sign
                    else
                    {
                        if (previousIncorrectSign != predictedSign)
                        {
                            timer = DateTime.Now;
                            previousIncorrectSign = predictedSign;
                        }
                        else if (predictedSign != null && currentSign != null &&
                            (DateTime.Now - timer).TotalSeconds > 2.0f)
                        {
                            NextSignIfCorrect(currentSign, predictedSign);
                            timer = DateTime.Now;
                            predictedSign = null;
                            previousIncorrectSign = null;
                        }
                    }
                }
            }
            else if (feedbackProgress != null)
            {
                feedbackProgress.value = 0.0f;
            }
        }
    }

    /// <summary>
    /// Function to check equality between the current sign and the sign that the model predicted, if they are equal then the next sign is fetched.
    /// </summary>
    /// <param name="predicted"></param>
    private void NextSignIfCorrect(string current, string predicted)
    {
        if (current == predicted)
            NextSign();

        // TODO: @Tibe cache the incorrect values here
    }
}