using UnityEngine;
using UnityEngine.UI;
using ZXing;
using ZXing.QrCode;
using ZXing.Common;
using ZXing.Rendering;
using ZXing.QrCode.Internal;

namespace Kill.UI.Components
{
    /// <summary>
    /// 二维码生成器
    /// 支持生成用户ID等文本的二维码图片
    /// </summary>
    public class QRCodeGenerator : MonoBehaviour
    {
        [Header("显示组件")]
        public RawImage qrCodeImage;            // 显示二维码的RawImage
        public int textureSize = 256;           // 二维码图片尺寸（像素）

        [Header("二维码样式")]
        public Color foregroundColor = Color.black;  // 前景色（二维码颜色）
        public Color backgroundColor = Color.white;  // 背景色
        public int margin = 2;                      // 边距

        // 当前生成的纹理
        private Texture2D currentTexture;
        // void Start()
        // {
        //     Generate("123123");
        // }
        /// <summary>
        /// 生成二维码
        /// </summary>
        /// <param name="content">二维码内容（如用户ID）</param>
        public void Generate(string content)
        {
            if (string.IsNullOrEmpty(content))
            {
                Debug.LogWarning("[QRCodeGenerator] 内容为空，无法生成二维码");
                return;
            }

            // 生成二维码纹理
            Texture2D texture = GenerateQRCodeTexture(content, textureSize, textureSize);

            if (texture != null)
            {
                // 清理旧纹理
                if (currentTexture != null)
                {
                    Destroy(currentTexture);
                }

                currentTexture = texture;

                // 显示二维码
                if (qrCodeImage != null)
                {
                    qrCodeImage.texture = currentTexture;
                    qrCodeImage.SetNativeSize();

                    // 可以在这里调整显示大小
                    float scale = Mathf.Min(
                        qrCodeImage.rectTransform.rect.width / textureSize,
                        qrCodeImage.rectTransform.rect.height / textureSize
                    );
                    qrCodeImage.rectTransform.sizeDelta = new Vector2(textureSize * scale, textureSize * scale);
                }

                Debug.Log($"[QRCodeGenerator] 二维码生成成功: {content}");
            }
        }

        /// <summary>
        /// 生成用户ID二维码
        /// </summary>
        /// <param name="userId">用户ID</param>
        public void GenerateUserQRCode(string userId)
        {
            // 可以添加前缀标识这是用户ID
            string content = $"USER:{userId}";
            Generate(content);
        }

        /// <summary>
        /// 生成设备分享二维码
        /// </summary>
        /// <param name="deviceId">设备ID</param>
        /// <param name="userId">用户ID</param>
        public void GenerateDeviceShareQRCode(string deviceId, string userId)
        {
            // 格式: DEVICE:设备ID:用户ID
            string content = $"DEVICE:{deviceId}:{userId}";
            Generate(content);
        }

        /// <summary>
        /// 生成二维码纹理
        /// </summary>
        private Texture2D GenerateQRCodeTexture(string content, int width, int height)
        {
            try
            {
                // 配置二维码参数
                var options = new QrCodeEncodingOptions
                {
                    Width = width,
                    Height = height,
                    Margin = margin,
                    CharacterSet = "UTF-8",
                    ErrorCorrection = ErrorCorrectionLevel.M  // 中等容错率
                };

                // 创建写入器
                var writer = new BarcodeWriter<Texture2D>
                {
                    Format = BarcodeFormat.QR_CODE,
                    Options = options,
                    Renderer = new ZXingRender()
                };

                // 生成二维码
                Texture2D texture = writer.Write(content);

                // 应用颜色
                ApplyColors(texture, foregroundColor, backgroundColor);

                return texture;
            }
            catch (System.Exception ex)
            {
                Debug.LogError($"[QRCodeGenerator] 生成二维码失败: {ex.Message}");
                return null;
            }
        }

        /// <summary>
        /// 应用自定义颜色到二维码
        /// </summary>
        private void ApplyColors(Texture2D texture, Color foreground, Color background)
        {
            Color32[] pixels = texture.GetPixels32();

            for (int i = 0; i < pixels.Length; i++)
            {
                // 黑色像素变前景色，白色像素变背景色
                if (pixels[i].r < 128)
                {
                    pixels[i] = foreground;
                }
                else
                {
                    pixels[i] = background;
                }
            }

            texture.SetPixels32(pixels);
            texture.Apply();
        }

        /// <summary>
        /// 保存二维码到相册（移动端）
        /// </summary>
        public void SaveToGallery(string filename = "QRCode")
        {
            if (currentTexture == null)
            {
                Debug.LogWarning("[QRCodeGenerator] 没有可保存的二维码");
                return;
            }

            // 将纹理转为PNG字节
            byte[] bytes = currentTexture.EncodeToPNG();

            // 保存到相册
#if UNITY_ANDROID
            string path = $"/storage/emulated/0/DCIM/{filename}.png";
            System.IO.File.WriteAllBytes(path, bytes);

            // 刷新相册
            using (AndroidJavaClass unityPlayer = new AndroidJavaClass("com.unity3d.player.UnityPlayer"))
            {
                using (AndroidJavaObject currentActivity = unityPlayer.GetStatic<AndroidJavaObject>("currentActivity"))
                {
                    using (AndroidJavaObject mediaScanner = new AndroidJavaObject("android.media.MediaScannerConnection"))
                    {
                        mediaScanner.CallStatic("scanFile", currentActivity, new string[] { path }, null, null);
                    }
                }
            }
#elif UNITY_IOS
            // iOS 使用原生插件保存
            // NativeGallery.SaveImageToGallery(currentTexture, "QRCode", filename);
#else
            string path = System.IO.Path.Combine(Application.persistentDataPath, $"{filename}.png");
            System.IO.File.WriteAllBytes(path, bytes);
            Debug.Log($"[QRCodeGenerator] 二维码已保存到: {path}");
#endif

            ToastUI.Show("二维码已保存到相册");
        }

        /// <summary>
        /// 获取当前二维码纹理
        /// </summary>
        public Texture2D GetCurrentTexture()
        {
            return currentTexture;
        }

        /// <summary>
        /// 清除二维码
        /// </summary>
        public void Clear()
        {
            if (currentTexture != null)
            {
                Destroy(currentTexture);
                currentTexture = null;
            }

            if (qrCodeImage != null)
            {
                qrCodeImage.texture = null;
            }
        }

        private void OnDestroy()
        {
            Clear();
        }
    }

    /// <summary>
    /// ZXing 纹理渲染器
    /// </summary>
    public class ZXingRender : IBarcodeRenderer<Texture2D>
    {
        public Texture2D Render(BitMatrix matrix, BarcodeFormat format, string content)
        {
            return Render(matrix, format, content, null);
        }

        public Texture2D Render(BitMatrix matrix, BarcodeFormat format, string content, EncodingOptions options)
        {
            int width = matrix.Width;
            int height = matrix.Height;
            Texture2D texture = new Texture2D(width, height, TextureFormat.RGBA32, false);

            Color32[] pixels = new Color32[width * height];

            for (int y = 0; y < height; y++)
            {
                for (int x = 0; x < width; x++)
                {
                    pixels[y * width + x] = matrix[x, y] ? Color.black : Color.white;
                }
            }

            texture.SetPixels32(pixels);
            texture.Apply();
            texture.filterMode = FilterMode.Point;  // 保持像素清晰

            return texture;
        }
    }
}