using System;
using Android.Content;
using Android.Graphics;
using Android.Views;

namespace Shared
{

    /// <summary>
    /// GradientMaskView
    /// </summary>
    public class GradientMaskView : View
    {
        /// <summary>
        ///  当前视图
        /// </summary>
        /// <value>The android GradientMaskView.</value>
        GradientButton mGradientButton
        {
            get
            {
                return AndroidView as GradientButton;
            }
            set
            {
                AndroidView = value;
            }
        }

        /// <summary>
        /// 构造函数
        /// </summary>
        public GradientMaskView()
        {
            mGradientButton = new GradientButton(Application.Activity, this);
            SetGradientColors(mGradientColors);

        }

        public bool IsShow
        {
            get
            {
                return mGradientButton.IsShow;

            }
            set
            {
                mGradientButton.IsShow = value;

            }

        }

        /// <summary>
        /// 0%，25%，50%，80%
        /// </summary>
        uint[] mGradientColors = { 0x00000000, 0x40000000, 0x80000000, 0xCC000000 };
        public uint[] GradientColors
        {
            get
            {
                return mGradientColors;

            }
            set
            {
                mGradientColors = value;
                SetGradientColors(mGradientColors);

            }
        }

        void SetGradientColors(uint[] colors)
        {
            if (colors == null || colors.Length == 0) return;

            int[] mCGColors = new int[colors.Length];
             
            for (int i = 0; i < colors.Length; i++)
            {
                mCGColors[i] = HDLUtils.GetUIColorWithUint(colors[i]);
            }
            mGradientButton.GradientColors = mCGColors;
        }



        public class GradientButton : Android.Views.View
        {
            View view;
            public GradientButton(Context context, View view)
                : base(context)
            {
                this.view = view;
                initPaint();

            }

            public override bool OnTouchEvent(MotionEvent e)
            {
                var v = base.OnTouchEvent(e);
                view?.TouchEvent(e);
                return true;
            }

            // 初始化进度圆弧画笔
            private void initPaint()
            {
                mPaint = new Paint();      //初始化进度圆弧画笔
                mPaint.AntiAlias = true;
                mPaint.SetStyle(Paint.Style.Fill);

            }

            /// <summary>
            /// 绘图的Paint
            /// </summary>
            private Paint mPaint;

            protected override void OnDraw(Canvas canvas)
            {
                base.OnDraw(canvas);

                if (isShow)
                {
                    canvas.Save();
                    DrawWithGradient(canvas);
                    canvas.Restore();
                }
            }

            /// <summary>
            /// 绘制渐变效果
            /// </summary>
            /// <param name="canvas"></param>
            void DrawWithGradient(Canvas canvas)
            {
                var gradient = new LinearGradient(0, 0, 0, Height, mGradientColors, null, Shader.TileMode.Mirror);
                mPaint.SetShader(gradient);

                canvas.DrawRect(0, 0, Width, Height, mPaint);
            }

            public int[] mGradientColors = { Android.Graphics.Color.Transparent };

            public int[] GradientColors
            {
                get
                {
                    return mGradientColors;
                }
                set
                {
                    mGradientColors = value;
                    PostInvalidate();
                }
            }

            bool isShow = true;
            public bool IsShow
            {
                get
                {
                    return isShow;
                }
                set
                {
                    isShow = value;
                    PostInvalidate();
                }

            }

          

        }
    }

}