using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class textEffect : MonoBehaviour {

    [Tooltip("Text to show")]
    public string text;
    [Tooltip("Space between characters. Default: 0.11")]
    public float characterSpacing;
    [Tooltip("Size of the characters")]
    public int fontSize;
    [Space]

    [Tooltip("Distance between the spawn position and the final position")]
    public float zOrigin;
    [Space]

    [Tooltip("Time between spawn and the final position")]
    public float animationDuration;
    [Tooltip("0 means infinite")]
    public float despawnTime;
    [Tooltip("Duration of the despawn effect")]
    public float fadeOutDuration;
    [Tooltip("Time between every character spawn")]
    public float characterDelay;
    [Tooltip("Delay applied to all characters")]
    public float characterOffsetDelay = 0;
    [Space]

    [Range(0,1)]
    [Tooltip("Random variation applied to every char")]
    public float errorRange;

    private float velocityIncrement;

    private Vector3[] localInitPosition;
    private Vector3[] localFinalPosition;
    private GameObject[] charactersGO;
    private float[] characterTime;
    private TextMesh[] characterTextMesh;
    private float time = 0;

    private float generalScale = 0.15f;

    private bool showScreens = true;
    private ScreenAnchor screenAnchor;
    private float videoDisplacement = 10;
    private Vector3 anchorFinalPosition;
    private Vector3 anchorInitPosition;

    private void OnEnable() {
        Setup();
    }

    void Setup() {
        //Moving the screen anchor
        showScreens = false;
        screenAnchor = transform.parent.GetComponent<Room>().screenAnchor.GetComponent<ScreenAnchor>();



        velocityIncrement = 1 / animationDuration;

        float spacingTotal = 0;

        localFinalPosition = new Vector3[text.Length];
        localInitPosition = new Vector3[text.Length];
        charactersGO = new GameObject[text.Length];
        characterTime = new float[text.Length];
        characterTextMesh = new TextMesh[text.Length];

        DestroyAll(true);

        for (int i = 0; i < text.Length; i++) {
            GameObject character = new GameObject("Character " + i);
            character.transform.parent = transform;

            TextMesh char3DText = character.AddComponent<TextMesh>();
            char3DText.fontSize = fontSize;
            char3DText.text = text.Substring(i, 1);

            character.transform.localScale = new Vector3(generalScale, generalScale, generalScale);

            CharacterInfo info;
            char3DText.font.GetCharacterInfo(char3DText.text[0], out info, char3DText.fontSize, char3DText.fontStyle);

            localInitPosition[i] = new Vector3(spacingTotal, 0, zOrigin + spacingTotal * Random.Range(-errorRange/2, errorRange/2));
            localInitPosition[i] += transform.position;
            localFinalPosition[i] = new Vector3(spacingTotal, 0, 0);
            localFinalPosition[i] += transform.position;
            character.transform.position = localInitPosition[i];

            charactersGO[i] = character;
            characterTime[i] = -characterDelay * i;
            characterTime[i] -= characterOffsetDelay;
            characterTextMesh[i] = char3DText;
            characterTextMesh[i].color = new Color(1, 1, 1, 0);
            spacingTotal += info.advance * characterSpacing * generalScale;
        }

        for (int i = 0; i < text.Length; i++) {
            localInitPosition[i].x -= spacingTotal / 2;
            localFinalPosition[i].x -= spacingTotal / 2;
        }
    }

    // Update is called once per frame
    void Update() {
        bool canDestroy = true;
        for (int i = 0; i < text.Length; i++) {
            float easeLerp = 0;
            if (characterTime[i] < 0) {
                easeLerp = 0;
                charactersGO[i].transform.position = Vector3.Lerp(localInitPosition[i], localFinalPosition[i], easeLerp);
                characterTextMesh[i].color = new Color(1, 1, 1, easeLerp);
            }
            else if (characterTime[i] < animationDuration) {
                easeLerp = Mathf.Sin((characterTime[i] / animationDuration) * Mathf.PI / 2);
                charactersGO[i].transform.position = Vector3.Lerp(localInitPosition[i], localFinalPosition[i], easeLerp);
                characterTextMesh[i].color = new Color(1, 1, 1, easeLerp);
            }
            else {
                if (characterTime[i] > despawnTime && despawnTime != 0) { //if despawnTime == 0, don't despawn.
                    characterTextMesh[i].color = new Color(1, 1, 1, 1 - (characterTime[i] - despawnTime) / fadeOutDuration);
                    showScreens = true;
                }
            }
            characterTime[i] += Time.deltaTime;

            if (despawnTime == 0 || characterTime[i] <= 0 + (despawnTime + fadeOutDuration)) {
                canDestroy = false;
            }
        }

        if (canDestroy) { //Destroy all characters
            DestroyAll(false);
        }

        if (showScreens) {
            screenAnchor.transform.position = Vector3.Lerp(screenAnchor.transform.position, screenAnchor.showingPosition, 0.05f);
        }
        else {
            screenAnchor.transform.position = screenAnchor.hiddenPosition;
        }
    }

    void DestroyAll(bool deactivateSpawner) {
        int tmp = charactersGO.Length - 1;
        while (tmp >= 0) {
            Destroy(charactersGO[tmp]);
            tmp--;
        }
        gameObject.SetActive(deactivateSpawner);
    }

    public void OnRoomExit() {
        DestroyAll(false);
    }
}