// Author: Daniele Giardini - http://www.demigiant.com
// Created: 2018/07/13

#if true && (UNITY_4_3 || UNITY_4_4 || UNITY_4_5 || UNITY_4_6 || UNITY_5 || UNITY_2017_1_OR_NEWER) // MODULE_MARKER
using System;
using UnityEngine;
using DG.Tweening.Core;
using DG.Tweening.Plugins.Options;

#pragma warning disable 1591
namespace DG.Tweening
{
	public static class DOTweenModuleSprite
    {
        #region Shortcuts

        #region SpriteRenderer

        /// <summary>Tweens a SpriteRenderer's color to the given value.
        /// Also stores the spriteRenderer as the tween's target so it can be used for filtered operations</summary>
        /// <param name="endValue">The end value to reach</param><param name="duration">The duration of the tween</param>
        public static TweenerCore<Color, Color, ColorOptions> DOColor(this SpriteRenderer target, Color endValue, float duration)
        {
            TweenerCore<Color, Color, ColorOptions> t = DOTween.To(() => target.color, x => target.color = x, endValue, duration);
            t.SetTarget(target);
            return t;
        }

        /// <summary>Tweens a Material's alpha color to the given value.
        /// Also stores the spriteRenderer as the tween's target so it can be used for filtered operations</summary>
        /// <param name="endValue">The end value to reach</param><param name="duration">The duration of the tween</param>
        public static TweenerCore<Color, Color, ColorOptions> DOFade(this SpriteRenderer target, float endValue, float duration)
        {
            TweenerCore<Color, Color, ColorOptions> t = DOTween.ToAlpha(() => target.color, x => target.color = x, endValue, duration);
            t.SetTarget(target);
            return t;
        }

        /// <summary>Tweens a SpriteRenderer's color using the given gradient
        /// (NOTE 1: only uses the colors of the gradient, not the alphas - NOTE 2: creates a Sequence, not a Tweener).
        /// Also stores the image as the tween's target so it can be used for filtered operations</summary>
        /// <param name="gradient">The gradient to use</param><param name="duration">The duration of the tween</param>
        public static Sequence DOGradientColor(this SpriteRenderer target, Gradient gradient, float duration)
        {
            Sequence s = DOTween.Sequence();
            GradientColorKey[] colors = gradient.colorKeys;
            int len = colors.Length;
            for (int i = 0; i < len; ++i) {
                GradientColorKey c = colors[i];
                if (i == 0 && c.time <= 0) {
                    target.color = c.color;
                    continue;
                }
                float colorDuration = i == len - 1
                    ? duration - s.Duration(false) // Verifies that total duration is correct
                    : duration * (i == 0 ? c.time : c.time - colors[i - 1].time);
                s.Append(target.DOColor(c.color, colorDuration).SetEase(Ease.Linear));
            }
            s.SetTarget(target);
            return s;
        }

        #endregion

        #region Blendables

        #region SpriteRenderer

        /// <summary>Tweens a SpriteRenderer's color to the given value,
        /// in a way that allows other DOBlendableColor tweens to work together on the same target,
        /// instead than fight each other as multiple DOColor would do.
        /// Also stores the SpriteRenderer as the tween's target so it can be used for filtered operations</summary>
        /// <param name="endValue">The value to tween to</param><param name="duration">The duration of the tween</param>
        public static Tweener DOBlendableColor(this SpriteRenderer target, Color endValue, float duration)
        {
            endValue = endValue - target.color;
            Color to = new Color(0, 0, 0, 0);
            return DOTween.To(() => to, x => {
                    Color diff = x - to;
                    to = x;
                    target.color += diff;
                }, endValue, duration)
                .Blendable().SetTarget(target);
        }

        #endregion

        #endregion

        #endregion
	}
}
#endif
