// COPYRIGHT (C) Tom. ALL RIGHTS RESERVED.
// THE AntdUI PROJECT IS AN WINFORM LIBRARY LICENSED UNDER THE Apache-2.0 License.
// LICENSED UNDER THE Apache License, VERSION 2.0 (THE "License")
// YOU MAY NOT USE THIS FILE EXCEPT IN COMPLIANCE WITH THE License.
// YOU MAY OBTAIN A COPY OF THE LICENSE AT
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING, SOFTWARE
// DISTRIBUTED UNDER THE LICENSE IS DISTRIBUTED ON AN "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
// SEE THE LICENSE FOR THE SPECIFIC LANGUAGE GOVERNING PERMISSIONS AND
// LIMITATIONS UNDER THE License.
// GITEE: https://gitee.com/antdui/AntdUI
// GITHUB: https://github.com/AntdUI/AntdUI
// CSDN: https://blog.csdn.net/v_132
// QQ: 17379620

using System;
using System.Drawing;
using System.Drawing.Imaging;

namespace AntdUI
{
    public unsafe class UnsafeBitmap : IDisposable
    {
        public ColorBgra* Pointer { get; private set; }
        public bool IsLocked { get; private set; }
        public int Width { get; private set; }
        public int Height { get; private set; }

        public int PixelCount => Width * Height;

        private Bitmap bitmap;
        private BitmapData bitmapData;

        public UnsafeBitmap(Bitmap bitmap, bool lockBitmap = false, ImageLockMode imageLockMode = ImageLockMode.ReadWrite)
        {
            this.bitmap = bitmap;
            Width = bitmap.Width;
            Height = bitmap.Height;

            if (lockBitmap)
            {
                Lock(imageLockMode);
            }
        }

        public void Lock(ImageLockMode imageLockMode = ImageLockMode.ReadWrite)
        {
            if (!IsLocked)
            {
                IsLocked = true;
                bitmapData = bitmap.LockBits(new Rectangle(0, 0, Width, Height), imageLockMode, PixelFormat.Format32bppArgb);
                Pointer = (ColorBgra*)bitmapData.Scan0.ToPointer();
            }
        }

        public void Unlock()
        {
            if (IsLocked)
            {
                bitmap.UnlockBits(bitmapData);
                bitmapData = null;
                Pointer = null;
                IsLocked = false;
            }
        }

        public static bool operator ==(UnsafeBitmap bmp1, UnsafeBitmap bmp2)
        {
            return ReferenceEquals(bmp1, bmp2) || bmp1.Equals(bmp2);
        }

        public static bool operator !=(UnsafeBitmap bmp1, UnsafeBitmap bmp2)
        {
            return !(bmp1 == bmp2);
        }

        public override bool Equals(object? obj)
        {
            return obj is UnsafeBitmap unsafeBitmap && Compare(unsafeBitmap, this);
        }

        public override int GetHashCode()
        {
            return PixelCount;
        }

        public static bool Compare(UnsafeBitmap bmp1, UnsafeBitmap bmp2)
        {
            int pixelCount = bmp1.PixelCount;

            if (pixelCount != bmp2.PixelCount)
            {
                return false;
            }

            bmp1.Lock(ImageLockMode.ReadOnly);
            bmp2.Lock(ImageLockMode.ReadOnly);

            ColorBgra* pointer1 = bmp1.Pointer;
            ColorBgra* pointer2 = bmp2.Pointer;

            for (int i = 0; i < pixelCount; i++)
            {
                if (pointer1->Bgra != pointer2->Bgra)
                {
                    return false;
                }

                pointer1++;
                pointer2++;
            }

            return true;
        }

        public bool IsTransparent()
        {
            int pixelCount = PixelCount;

            ColorBgra* pointer = Pointer;

            for (int i = 0; i < pixelCount; i++)
            {
                if (pointer->Alpha < 255)
                {
                    return true;
                }

                pointer++;
            }

            return false;
        }

        public ColorBgra GetPixel(int i)
        {
            return Pointer[i];
        }

        public ColorBgra GetPixel(int x, int y)
        {
            return Pointer[x + (y * Width)];
        }

        public void SetPixel(int i, ColorBgra color)
        {
            Pointer[i] = color;
        }

        public void SetPixel(int i, uint color)
        {
            Pointer[i] = color;
        }

        public void SetPixel(int x, int y, ColorBgra color)
        {
            Pointer[x + (y * Width)] = color;
        }

        public void SetPixel(int x, int y, uint color)
        {
            Pointer[x + (y * Width)] = color;
        }

        public void ClearPixel(int i)
        {
            Pointer[i] = 0;
        }

        public void ClearPixel(int x, int y)
        {
            Pointer[x + (y * Width)] = 0;
        }

        public void Dispose()
        {
            Unlock();
        }
    }
}