using UnityEngine;
using UnityEditor;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;

namespace UnityVersionControl
{
    /// <summary>
    /// Advanced File Diff Viewer for Unity Assets
    /// Supports text diffs, visual comparisons, and property changes
    /// </summary>
    public class FileDiffViewer : EditorWindow
    {
        #region Fields
        private Vector2 scrollPosition;
        private int selectedViewMode = 0;
        private readonly string[] viewModeNames = { "Split View", "Unified Diff", "Visual Compare" };
        
        private string currentFilePath = "";
        private DiffData currentDiff;
        private Texture2D leftTexture;
        private Texture2D rightTexture;
        
        // UI state
        private bool showLineNumbers = true;
        private bool showWhitespace = false;
        private bool wordWrap = false;
        private int contextLines = 3;
        private string searchText = "";
        
        // Visual constants
        private static readonly Color backgroundColor = new Color(0.22f, 0.22f, 0.22f);
        private static readonly Color cardColor = new Color(0.28f, 0.28f, 0.28f);
        private static readonly Color addedColor = new Color(0.2f, 0.6f, 0.2f, 0.3f);
        private static readonly Color removedColor = new Color(0.6f, 0.2f, 0.2f, 0.3f);
        private static readonly Color modifiedColor = new Color(0.6f, 0.4f, 0.2f, 0.3f);
        private static readonly Color lineNumberColor = new Color(0.5f, 0.5f, 0.5f);
        private static readonly Color contextColor = new Color(0.8f, 0.8f, 0.8f);
        
        // Caches
        private readonly Dictionary<string, Texture2D> textureCache = new Dictionary<string, Texture2D>();
        private readonly Dictionary<string, DiffData> diffCache = new Dictionary<string, DiffData>();
        #endregion

        #region Unity Lifecycle
        [MenuItem("Window/Version Control/File Diff Viewer", false, 3)]
        public static void ShowWindow()
        {
            var window = GetWindow<FileDiffViewer>();
            window.titleContent = new GUIContent("File Diff");
            window.minSize = new Vector2(800, 600);
        }

        public static void ShowDiff(string filePath)
        {
            var window = GetWindow<FileDiffViewer>();
            window.titleContent = new GUIContent($"Diff: {System.IO.Path.GetFileName(filePath)}");
            window.minSize = new Vector2(800, 600);
            window.LoadFile(filePath);
        }

        private void OnEnable()
        {
            LoadTestData();
        }

        private void OnDisable()
        {
            CleanupTextures();
        }

        private void OnGUI()
        {
            DrawBackground();
            DrawToolbar();
            DrawDiffContent();
        }
        #endregion

        #region File Loading
        public void LoadFile(string filePath)
        {
            currentFilePath = filePath;
            
            if (diffCache.TryGetValue(filePath, out var cachedDiff))
            {
                currentDiff = cachedDiff;
            }
            else
            {
                currentDiff = GenerateDiff(filePath);
                diffCache[filePath] = currentDiff;
            }
            
            LoadAssetTextures(filePath);
            Repaint();
        }

        private void LoadTestData()
        {
            // Load a test diff for demonstration
            LoadFile("Assets/Scripts/PlayerController.cs");
        }

        private DiffData GenerateDiff(string filePath)
        {
            var extension = System.IO.Path.GetExtension(filePath).ToLower();
            
            switch (extension)
            {
                case ".cs":
                case ".js":
                case ".shader":
                case ".hlsl":
                case ".cginc":
                    return GenerateCodeDiff(filePath);
                
                case ".unity":
                case ".prefab":
                case ".asset":
                case ".mat":
                    return GenerateAssetDiff(filePath);
                
                case ".png":
                case ".jpg":
                case ".jpeg":
                case ".tga":
                    return GenerateImageDiff(filePath);
                
                default:
                    return GenerateTextDiff(filePath);
            }
        }

        private DiffData GenerateCodeDiff(string filePath)
        {
            // Mock C# code diff
            var diff = new DiffData
            {
                filePath = filePath,
                diffType = DiffType.Code,
                leftContent = GetMockCodeContent(true),
                rightContent = GetMockCodeContent(false),
                lines = new List<DiffLine>()
            };
            
            diff.lines = GenerateDiffLines(diff.leftContent, diff.rightContent);
            return diff;
        }

        private DiffData GenerateAssetDiff(string filePath)
        {
            // Mock Unity asset property diff
            var diff = new DiffData
            {
                filePath = filePath,
                diffType = DiffType.Properties,
                leftContent = GetMockAssetContent(true),
                rightContent = GetMockAssetContent(false),
                propertyChanges = GeneratePropertyChanges()
            };
            
            return diff;
        }

        private DiffData GenerateImageDiff(string filePath)
        {
            // Mock image diff
            var diff = new DiffData
            {
                filePath = filePath,
                diffType = DiffType.Image,
                leftImagePath = "Assets/Textures/PlayerTexture_Old.png",
                rightImagePath = "Assets/Textures/PlayerTexture_New.png"
            };
            
            return diff;
        }

        private DiffData GenerateTextDiff(string filePath)
        {
            // Generic text diff
            var diff = new DiffData
            {
                filePath = filePath,
                diffType = DiffType.Text,
                leftContent = "Original content line 1\nOriginal content line 2\nShared line 3\nOriginal line 4",
                rightContent = "Modified content line 1\nNew line 2\nShared line 3\nModified line 4\nNew line 5"
            };
            
            diff.lines = GenerateDiffLines(diff.leftContent, diff.rightContent);
            return diff;
        }

        private void LoadAssetTextures(string filePath)
        {
            if (currentDiff?.diffType == DiffType.Image)
            {
                leftTexture = LoadTextureFromPath(currentDiff.leftImagePath);
                rightTexture = LoadTextureFromPath(currentDiff.rightImagePath);
            }
        }

        private Texture2D LoadTextureFromPath(string path)
        {
            try
            {
                return AssetDatabase.LoadAssetAtPath<Texture2D>(path);
            }
            catch
            {
                // Return a placeholder texture
                return CreateSolidColorTexture(Color.gray, 256, 256);
            }
        }
        #endregion

        #region Mock Data Generation
        private string GetMockCodeContent(bool isOld)
        {
            if (isOld)
            {
                return @"using UnityEngine;

public class PlayerController : MonoBehaviour
{
    public float speed = 5.0f;
    public float jumpForce = 8.0f;
    
    private Rigidbody rb;
    
    void Start()
    {
        rb = GetComponent<Rigidbody>();
    }
    
    void Update()
    {
        float horizontal = Input.GetAxis(""Horizontal"");
        float vertical = Input.GetAxis(""Vertical"");
        
        Vector3 movement = new Vector3(horizontal, 0, vertical);
        transform.Translate(movement * speed * Time.deltaTime);
        
        if (Input.GetKeyDown(KeyCode.Space))
        {
            rb.AddForce(Vector3.up * jumpForce, ForceMode.Impulse);
        }
    }
}";
            }
            else
            {
                return @"using UnityEngine;

public class PlayerController : MonoBehaviour
{
    [Header(""Movement Settings"")]
    public float speed = 7.0f;
    public float jumpForce = 10.0f;
    public float groundCheckDistance = 0.1f;
    
    private Rigidbody rb;
    private bool isGrounded;
    
    void Start()
    {
        rb = GetComponent<Rigidbody>();
    }
    
    void Update()
    {
        CheckGrounded();
        HandleMovement();
        HandleJumping();
    }
    
    void CheckGrounded()
    {
        isGrounded = Physics.Raycast(transform.position, Vector3.down, groundCheckDistance);
    }
    
    void HandleMovement()
    {
        float horizontal = Input.GetAxis(""Horizontal"");
        float vertical = Input.GetAxis(""Vertical"");
        
        Vector3 movement = new Vector3(horizontal, 0, vertical).normalized;
        rb.velocity = new Vector3(movement.x * speed, rb.velocity.y, movement.z * speed);
    }
    
    void HandleJumping()
    {
        if (Input.GetKeyDown(KeyCode.Space) && isGrounded)
        {
            rb.AddForce(Vector3.up * jumpForce, ForceMode.Impulse);
        }
    }
}";
            }
        }

        private string GetMockAssetContent(bool isOld)
        {
            if (isOld)
            {
                return @"Transform:
  position: {x: 0, y: 0, z: 0}
  rotation: {x: 0, y: 0, z: 0, w: 1}
  scale: {x: 1, y: 1, z: 1}
MeshRenderer:
  material: PlayerMaterial
  receiveShadows: 1
BoxCollider:
  size: {x: 1, y: 1, z: 1}
  center: {x: 0, y: 0, z: 0}";
            }
            else
            {
                return @"Transform:
  position: {x: 0, y: 0.5, z: 0}
  rotation: {x: 0, y: 0, z: 0, w: 1}
  scale: {x: 1.2, y: 1.2, z: 1.2}
MeshRenderer:
  material: PlayerMaterial_Updated
  receiveShadows: 1
  shadowCastingMode: 1
BoxCollider:
  size: {x: 1.1, y: 1.1, z: 1.1}
  center: {x: 0, y: 0, z: 0}
  isTrigger: 0
Rigidbody:
  mass: 1
  drag: 0.5";
            }
        }

        private List<PropertyChange> GeneratePropertyChanges()
        {
            return new List<PropertyChange>
            {
                new PropertyChange
                {
                    propertyName = "Transform.position.y",
                    oldValue = "0",
                    newValue = "0.5",
                    changeType = PropertyChangeType.Modified
                },
                new PropertyChange
                {
                    propertyName = "Transform.scale",
                    oldValue = "{x: 1, y: 1, z: 1}",
                    newValue = "{x: 1.2, y: 1.2, z: 1.2}",
                    changeType = PropertyChangeType.Modified
                },
                new PropertyChange
                {
                    propertyName = "MeshRenderer.material",
                    oldValue = "PlayerMaterial",
                    newValue = "PlayerMaterial_Updated",
                    changeType = PropertyChangeType.Modified
                },
                new PropertyChange
                {
                    propertyName = "MeshRenderer.shadowCastingMode",
                    oldValue = "",
                    newValue = "1",
                    changeType = PropertyChangeType.Added
                },
                new PropertyChange
                {
                    propertyName = "BoxCollider.size",
                    oldValue = "{x: 1, y: 1, z: 1}",
                    newValue = "{x: 1.1, y: 1.1, z: 1.1}",
                    changeType = PropertyChangeType.Modified
                },
                new PropertyChange
                {
                    propertyName = "Rigidbody",
                    oldValue = "",
                    newValue = "Component Added",
                    changeType = PropertyChangeType.Added
                }
            };
        }
        #endregion

        #region GUI Drawing
        private void DrawBackground()
        {
            var rect = new Rect(0, 0, position.width, position.height);
            EditorGUI.DrawRect(rect, backgroundColor);
        }

        private void DrawToolbar()
        {
            DrawCard(() =>
            {
                using (new EditorGUILayout.HorizontalScope())
                {
                    // File info
                    using (new EditorGUILayout.VerticalScope())
                    {
                        var titleStyle = new GUIStyle(EditorStyles.boldLabel);
                        titleStyle.fontSize = 14;
                        titleStyle.normal.textColor = Color.white;
                        EditorGUILayout.LabelField(System.IO.Path.GetFileName(currentFilePath), titleStyle);
                        
                        var pathStyle = new GUIStyle(EditorStyles.label);
                        pathStyle.normal.textColor = new Color(0.7f, 0.7f, 0.7f);
                        pathStyle.fontSize = 11;
                        EditorGUILayout.LabelField(currentFilePath, pathStyle);
                    }
                    
                    GUILayout.FlexibleSpace();
                    
                    // View mode selector
                    EditorGUILayout.LabelField("View:", GUILayout.Width(40));
                    selectedViewMode = EditorGUILayout.Popup(selectedViewMode, viewModeNames, GUILayout.Width(120));
                    
                    GUILayout.Space(8);
                    
                    // Options
                    showLineNumbers = EditorGUILayout.Toggle("Lines", showLineNumbers, GUILayout.Width(60));
                    showWhitespace = EditorGUILayout.Toggle("Space", showWhitespace, GUILayout.Width(60));
                    wordWrap = EditorGUILayout.Toggle("Wrap", wordWrap, GUILayout.Width(60));
                }
                
                EditorGUILayout.Space(4);
                
                // Search bar
                using (new EditorGUILayout.HorizontalScope())
                {
                    EditorGUILayout.LabelField("Search:", GUILayout.Width(50));
                    searchText = EditorGUILayout.TextField(searchText);
                    
                    if (GUILayout.Button("Clear", GUILayout.Width(50)))
                        searchText = "";
                }
            }, 12);
        }

        private void DrawDiffContent()
        {
            if (currentDiff == null)
            {
                DrawEmptyState();
                return;
            }
            
            EditorGUILayout.Space(8);
            
            switch (selectedViewMode)
            {
                case 0: DrawSplitView(); break;
                case 1: DrawUnifiedView(); break;
                case 2: DrawVisualCompare(); break;
            }
        }

        private void DrawEmptyState()
        {
            DrawCard(() =>
            {
                var iconRect = GUILayoutUtility.GetRect(48, 48);
                var emptyTexture = CreateSolidColorTexture(new Color(0.5f, 0.5f, 0.5f, 0.3f), 48, 48);
                GUI.DrawTexture(iconRect, emptyTexture);
                
                EditorGUILayout.Space(8);
                
                var titleStyle = new GUIStyle(EditorStyles.boldLabel);
                titleStyle.alignment = TextAnchor.MiddleCenter;
                titleStyle.normal.textColor = new Color(0.7f, 0.7f, 0.7f);
                EditorGUILayout.LabelField("No File Selected", titleStyle);
                
                var subtitleStyle = new GUIStyle(EditorStyles.label);
                subtitleStyle.alignment = TextAnchor.MiddleCenter;
                subtitleStyle.normal.textColor = new Color(0.6f, 0.6f, 0.6f);
                subtitleStyle.wordWrap = true;
                EditorGUILayout.LabelField("Select a modified file to view its diff.", subtitleStyle);
            }, 32);
        }

        private void DrawSplitView()
        {
            using (var scrollView = new EditorGUILayout.ScrollViewScope(scrollPosition))
            {
                scrollPosition = scrollView.scrollPosition;
                
                switch (currentDiff.diffType)
                {
                    case DiffType.Code:
                    case DiffType.Text:
                        DrawCodeSplitView();
                        break;
                    case DiffType.Properties:
                        DrawPropertySplitView();
                        break;
                    case DiffType.Image:
                        DrawImageSplitView();
                        break;
                }
            }
        }

        private void DrawCodeSplitView()
        {
            DrawCard(() =>
            {
                using (new EditorGUILayout.HorizontalScope())
                {
                    // Left panel header
                    using (new EditorGUILayout.VerticalScope())
                    {
                        var headerStyle = new GUIStyle(EditorStyles.boldLabel);
                        headerStyle.normal.textColor = removedColor;
                        headerStyle.alignment = TextAnchor.MiddleCenter;
                        EditorGUILayout.LabelField("BEFORE", headerStyle);
                        
                        DrawCodePanel(currentDiff.leftContent, true);
                    }
                    
                    GUILayout.Space(8);
                    
                    // Right panel header
                    using (new EditorGUILayout.VerticalScope())
                    {
                        var headerStyle = new GUIStyle(EditorStyles.boldLabel);
                        headerStyle.normal.textColor = addedColor;
                        headerStyle.alignment = TextAnchor.MiddleCenter;
                        EditorGUILayout.LabelField("AFTER", headerStyle);
                        
                        DrawCodePanel(currentDiff.rightContent, false);
                    }
                }
            }, 12);
        }

        private void DrawCodePanel(string content, bool isLeft)
        {
            var lines = content.Split('\n');
            var codeStyle = new GUIStyle(EditorStyles.textArea);
            codeStyle.wordWrap = wordWrap;
            codeStyle.richText = true;
            codeStyle.font = EditorGUIUtility.Load("Consolas") as Font ?? GUI.skin.font;
            
            for (int i = 0; i < lines.Length; i++)
            {
                using (new EditorGUILayout.HorizontalScope())
                {
                    if (showLineNumbers)
                    {
                        var lineNumStyle = new GUIStyle(EditorStyles.label);
                        lineNumStyle.normal.textColor = lineNumberColor;
                        lineNumStyle.fontSize = 10;
                        lineNumStyle.alignment = TextAnchor.MiddleRight;
                        EditorGUILayout.LabelField((i + 1).ToString(), lineNumStyle, GUILayout.Width(30));
                    }
                    
                    var line = lines[i];
                    if (!string.IsNullOrEmpty(searchText) && line.Contains(searchText))
                    {
                        line = line.Replace(searchText, $"<color=yellow>{searchText}</color>");
                    }
                    
                    var lineRect = EditorGUILayout.GetControlRect();
                    
                    // Highlight changed lines
                    var diffLine = GetDiffLineForIndex(i, isLeft);
                    if (diffLine != null)
                    {
                        Color bgColor = diffLine.type switch
                        {
                            DiffLineType.Added => addedColor,
                            DiffLineType.Removed => removedColor,
                            DiffLineType.Modified => modifiedColor,
                            _ => Color.clear
                        };
                        
                        if (bgColor != Color.clear)
                        {
                            EditorGUI.DrawRect(lineRect, bgColor);
                        }
                    }
                    
                    EditorGUI.LabelField(lineRect, line, codeStyle);
                }
            }
        }

        private void DrawPropertySplitView()
        {
            DrawCard(() =>
            {
                using (new EditorGUILayout.HorizontalScope())
                {
                    // Properties comparison
                    using (new EditorGUILayout.VerticalScope())
                    {
                        var headerStyle = new GUIStyle(EditorStyles.boldLabel);
                        headerStyle.alignment = TextAnchor.MiddleCenter;
                        EditorGUILayout.LabelField("PROPERTY CHANGES", headerStyle);
                        
                        EditorGUILayout.Space(8);
                        
                        foreach (var change in currentDiff.propertyChanges)
                        {
                            DrawPropertyChange(change);
                            EditorGUILayout.Space(4);
                        }
                    }
                }
            }, 12);
        }

        private void DrawPropertyChange(PropertyChange change)
        {
            var changeRect = EditorGUILayout.BeginHorizontal();
            
            Color bgColor = change.changeType switch
            {
                PropertyChangeType.Added => addedColor,
                PropertyChangeType.Removed => removedColor,
                PropertyChangeType.Modified => modifiedColor,
                _ => Color.clear
            };
            
            if (bgColor != Color.clear)
            {
                EditorGUI.DrawRect(changeRect, bgColor);
            }
            
            GUILayout.Space(8);
            
            // Property name
            var nameStyle = new GUIStyle(EditorStyles.boldLabel);
            nameStyle.normal.textColor = Color.white;
            nameStyle.fontSize = 11;
            EditorGUILayout.LabelField(change.propertyName, nameStyle, GUILayout.Width(200));
            
            // Change indicator
            var changeIcon = change.changeType switch
            {
                PropertyChangeType.Added => "＋",
                PropertyChangeType.Removed => "－",
                PropertyChangeType.Modified => "⟳",
                _ => "?"
            };
            
            var iconStyle = new GUIStyle(EditorStyles.label);
            iconStyle.normal.textColor = change.changeType switch
            {
                PropertyChangeType.Added => Color.green,
                PropertyChangeType.Removed => Color.red,
                PropertyChangeType.Modified => Color.yellow,
                _ => Color.white
            };
            EditorGUILayout.LabelField(changeIcon, iconStyle, GUILayout.Width(20));
            
            // Values
            using (new EditorGUILayout.VerticalScope())
            {
                if (!string.IsNullOrEmpty(change.oldValue))
                {
                    var oldStyle = new GUIStyle(EditorStyles.label);
                    oldStyle.normal.textColor = new Color(1f, 0.7f, 0.7f);
                    oldStyle.fontSize = 10;
                    EditorGUILayout.LabelField($"- {change.oldValue}", oldStyle);
                }
                
                if (!string.IsNullOrEmpty(change.newValue))
                {
                    var newStyle = new GUIStyle(EditorStyles.label);
                    newStyle.normal.textColor = new Color(0.7f, 1f, 0.7f);
                    newStyle.fontSize = 10;
                    EditorGUILayout.LabelField($"+ {change.newValue}", newStyle);
                }
            }
            
            GUILayout.Space(8);
            EditorGUILayout.EndHorizontal();
        }

        private void DrawImageSplitView()
        {
            DrawCard(() =>
            {
                using (new EditorGUILayout.HorizontalScope())
                {
                    // Left image
                    using (new EditorGUILayout.VerticalScope())
                    {
                        var headerStyle = new GUIStyle(EditorStyles.boldLabel);
                        headerStyle.normal.textColor = removedColor;
                        headerStyle.alignment = TextAnchor.MiddleCenter;
                        EditorGUILayout.LabelField("BEFORE", headerStyle);
                        
                        DrawImagePanel(leftTexture, "Old Version");
                    }
                    
                    GUILayout.Space(8);
                    
                    // Right image
                    using (new EditorGUILayout.VerticalScope())
                    {
                        var headerStyle = new GUIStyle(EditorStyles.boldLabel);
                        headerStyle.normal.textColor = addedColor;
                        headerStyle.alignment = TextAnchor.MiddleCenter;
                        EditorGUILayout.LabelField("AFTER", headerStyle);
                        
                        DrawImagePanel(rightTexture, "New Version");
                    }
                }
            }, 12);
        }

        private void DrawImagePanel(Texture2D texture, string label)
        {
            if (texture != null)
            {
                var maxSize = 300f;
                var aspect = (float)texture.width / texture.height;
                var displayWidth = aspect > 1 ? maxSize : maxSize * aspect;
                var displayHeight = aspect > 1 ? maxSize / aspect : maxSize;
                
                var imageRect = GUILayoutUtility.GetRect(displayWidth, displayHeight);
                EditorGUI.DrawRect(imageRect, Color.black);
                GUI.DrawTexture(imageRect, texture, ScaleMode.ScaleToFit);
                
                // Image info
                var infoStyle = new GUIStyle(EditorStyles.label);
                infoStyle.normal.textColor = new Color(0.7f, 0.7f, 0.7f);
                infoStyle.fontSize = 10;
                infoStyle.alignment = TextAnchor.MiddleCenter;
                EditorGUILayout.LabelField($"{texture.width}x{texture.height}", infoStyle);
            }
            else
            {
                var placeholderRect = GUILayoutUtility.GetRect(300, 200);
                EditorGUI.DrawRect(placeholderRect, new Color(0.3f, 0.3f, 0.3f));
                
                var labelStyle = new GUIStyle(EditorStyles.centeredGreyMiniLabel);
                labelStyle.normal.textColor = Color.white;
                GUI.Label(placeholderRect, label, labelStyle);
            }
        }

        private void DrawUnifiedView()
        {
            using (var scrollView = new EditorGUILayout.ScrollViewScope(scrollPosition))
            {
                scrollPosition = scrollView.scrollPosition;
                
                DrawCard(() =>
                {
                    if (currentDiff.lines != null && currentDiff.lines.Count > 0)
                    {
                        DrawUnifiedDiff();
                    }
                    else
                    {
                        var noChangesStyle = new GUIStyle(EditorStyles.centeredGreyMiniLabel);
                        noChangesStyle.normal.textColor = Color.white;
                        EditorGUILayout.LabelField("No textual changes to display", noChangesStyle);
                    }
                }, 12);
            }
        }

        private void DrawUnifiedDiff()
        {
            var codeStyle = new GUIStyle(EditorStyles.textArea);
            codeStyle.wordWrap = wordWrap;
            codeStyle.richText = true;
            codeStyle.font = EditorGUIUtility.Load("Consolas") as Font ?? GUI.skin.font;
            
            foreach (var line in currentDiff.lines)
            {
                using (new EditorGUILayout.HorizontalScope())
                {
                    if (showLineNumbers)
                    {
                        var lineNumStyle = new GUIStyle(EditorStyles.label);
                        lineNumStyle.normal.textColor = lineNumberColor;
                        lineNumStyle.fontSize = 10;
                        lineNumStyle.alignment = TextAnchor.MiddleRight;
                        
                        var lineNumber = line.type == DiffLineType.Removed ? line.leftLineNumber : line.rightLineNumber;
                        EditorGUILayout.LabelField(lineNumber > 0 ? lineNumber.ToString() : "", lineNumStyle, GUILayout.Width(30));
                    }
                    
                    var lineRect = EditorGUILayout.GetControlRect();
                    
                    // Background color based on line type
                    Color bgColor = line.type switch
                    {
                        DiffLineType.Added => addedColor,
                        DiffLineType.Removed => removedColor,
                        DiffLineType.Modified => modifiedColor,
                        _ => Color.clear
                    };
                    
                    if (bgColor != Color.clear)
                    {
                        EditorGUI.DrawRect(lineRect, bgColor);
                    }
                    
                    // Line prefix
                    var prefix = line.type switch
                    {
                        DiffLineType.Added => "+ ",
                        DiffLineType.Removed => "- ",
                        DiffLineType.Modified => "~ ",
                        _ => "  "
                    };
                    
                    var displayText = prefix + line.content;
                    if (!string.IsNullOrEmpty(searchText) && line.content.Contains(searchText))
                    {
                        displayText = displayText.Replace(searchText, $"<color=yellow>{searchText}</color>");
                    }
                    
                    EditorGUI.LabelField(lineRect, displayText, codeStyle);
                }
            }
        }

        private void DrawVisualCompare()
        {
            using (var scrollView = new EditorGUILayout.ScrollViewScope(scrollPosition))
            {
                scrollPosition = scrollView.scrollPosition;
                
                if (currentDiff.diffType == DiffType.Image)
                {
                    DrawImageOverlay();
                }
                else
                {
                    DrawSideBySideComparison();
                }
            }
        }

        private void DrawImageOverlay()
        {
            DrawCard(() =>
            {
                EditorGUILayout.LabelField("Image Overlay Comparison", EditorStyles.boldLabel);
                EditorGUILayout.Space(8);
                
                // TODO: Implement image overlay/blend comparison
                if (leftTexture != null && rightTexture != null)
                {
                    var maxSize = 400f;
                    var imageRect = GUILayoutUtility.GetRect(maxSize, maxSize);
                    
                    // For now, just show both images side by side
                    var leftRect = new Rect(imageRect.x, imageRect.y, imageRect.width * 0.5f, imageRect.height);
                    var rightRect = new Rect(imageRect.x + imageRect.width * 0.5f, imageRect.y, imageRect.width * 0.5f, imageRect.height);
                    
                    GUI.DrawTexture(leftRect, leftTexture, ScaleMode.ScaleToFit);
                    GUI.DrawTexture(rightRect, rightTexture, ScaleMode.ScaleToFit);
                }
                else
                {
                    EditorGUILayout.LabelField("Image overlay comparison not available", EditorStyles.centeredGreyMiniLabel);
                }
            }, 12);
        }

        private void DrawSideBySideComparison()
        {
            DrawSplitView(); // Fallback to split view for non-image assets
        }
        #endregion

        #region Helper Methods
        private void DrawCard(System.Action content, int padding = 12)
        {
            var rect = EditorGUILayout.BeginVertical();
            EditorGUI.DrawRect(rect, cardColor);
            
            GUILayout.Space(padding);
            EditorGUILayout.BeginHorizontal();
            GUILayout.Space(padding);
            EditorGUILayout.BeginVertical();
            
            content?.Invoke();
            
            EditorGUILayout.EndVertical();
            GUILayout.Space(padding);
            EditorGUILayout.EndHorizontal();
            GUILayout.Space(padding);
            
            EditorGUILayout.EndVertical();
        }

        private List<DiffLine> GenerateDiffLines(string leftContent, string rightContent)
        {
            var leftLines = leftContent.Split('\n');
            var rightLines = rightContent.Split('\n');
            var result = new List<DiffLine>();
            
            // Simple diff algorithm - in production, use a proper diff library
            var maxLines = Mathf.Max(leftLines.Length, rightLines.Length);
            
            for (int i = 0; i < maxLines; i++)
            {
                var leftLine = i < leftLines.Length ? leftLines[i] : null;
                var rightLine = i < rightLines.Length ? rightLines[i] : null;
                
                if (leftLine == null)
                {
                    result.Add(new DiffLine
                    {
                        content = rightLine,
                        type = DiffLineType.Added,
                        leftLineNumber = 0,
                        rightLineNumber = i + 1
                    });
                }
                else if (rightLine == null)
                {
                    result.Add(new DiffLine
                    {
                        content = leftLine,
                        type = DiffLineType.Removed,
                        leftLineNumber = i + 1,
                        rightLineNumber = 0
                    });
                }
                else if (leftLine == rightLine)
                {
                    result.Add(new DiffLine
                    {
                        content = leftLine,
                        type = DiffLineType.Context,
                        leftLineNumber = i + 1,
                        rightLineNumber = i + 1
                    });
                }
                else
                {
                    result.Add(new DiffLine
                    {
                        content = rightLine,
                        type = DiffLineType.Modified,
                        leftLineNumber = i + 1,
                        rightLineNumber = i + 1
                    });
                }
            }
            
            return result;
        }

        private DiffLine GetDiffLineForIndex(int index, bool isLeft)
        {
            if (currentDiff?.lines == null) return null;
            
            return currentDiff.lines.FirstOrDefault(line =>
                isLeft ? line.leftLineNumber == index + 1 : line.rightLineNumber == index + 1);
        }

        private Texture2D CreateSolidColorTexture(Color color, int width, int height)
        {
            var texture = new Texture2D(width, height);
            var pixels = new Color[width * height];
            for (int i = 0; i < pixels.Length; i++)
                pixels[i] = color;
            texture.SetPixels(pixels);
            texture.Apply();
            return texture;
        }

        private void CleanupTextures()
        {
            foreach (var texture in textureCache.Values)
            {
                if (texture != null) DestroyImmediate(texture);
            }
            textureCache.Clear();
        }
        #endregion
    }

    #region Data Models
    [Serializable]
    public class DiffData
    {
        public string filePath;
        public DiffType diffType;
        public string leftContent;
        public string rightContent;
        public string leftImagePath;
        public string rightImagePath;
        public List<DiffLine> lines;
        public List<PropertyChange> propertyChanges;
    }

    [Serializable]
    public class DiffLine
    {
        public string content;
        public DiffLineType type;
        public int leftLineNumber;
        public int rightLineNumber;
    }

    [Serializable]
    public class PropertyChange
    {
        public string propertyName;
        public string oldValue;
        public string newValue;
        public PropertyChangeType changeType;
    }

    public enum DiffType
    {
        Text,
        Code,
        Properties,
        Image,
        Binary
    }

    public enum DiffLineType
    {
        Context,
        Added,
        Removed,
        Modified
    }

    public enum PropertyChangeType
    {
        Added,
        Removed,
        Modified
    }
    #endregion
}