working basic UI

Author: MPCoreDeveloper

SharpCoreDB.Data.Provider/SharpCoreDBCommand.cs

@@ -1,6 +1,7 @@
 using System.Data;
 using System.Data.Common;
 using System.Diagnostics.CodeAnalysis;
+using SharpCoreDB.Interfaces;
 
 namespace SharpCoreDB.Data.Provider;
 
@@ -139,6 +140,16 @@ public override int ExecuteNonQuery()
             else
                 db.ExecuteSQL(CommandText!);
 
+            // ? CRITICAL FIX: Flush data after non-query commands to ensure persistence!
+            // Without this, INSERT/UPDATE/DELETE data only lives in memory until connection close.
+            var commandUpper = CommandText!.Trim().ToUpperInvariant();
+            if (commandUpper.StartsWith("INSERT") || 
+                commandUpper.StartsWith("UPDATE") || 
+                commandUpper.StartsWith("DELETE"))
+            {
+                db.Flush();
+            }
+
             // SharpCoreDB doesn't return rows affected, return -1 as per ADO.NET convention
             return -1;
         }
@@ -160,6 +171,13 @@ protected override DbDataReader ExecuteDbDataReader(CommandBehavior behavior)
             var db = Connection!.DbInstance!;
             var parameters = BuildParameterDictionary();
 
+            // ? FIX: Intercept SQLite system table queries and redirect to IMetadataProvider
+            var commandTextUpper = CommandText!.ToUpperInvariant().Trim();
+            if (commandTextUpper.Contains("SQLITE_MASTER") || commandTextUpper.Contains("SQLITE_SCHEMA"))
+            {
+                return ExecuteSystemTableQuery(commandTextUpper, behavior);
+            }
+
             List<Dictionary<string, object>> results;
             if (parameters.Count > 0)
                 results = db.ExecuteQuery(CommandText!, parameters);
@@ -174,6 +192,148 @@ protected override DbDataReader ExecuteDbDataReader(CommandBehavior behavior)
         }
     }
 
+    /// <summary>
+    /// Executes queries against SQLite system tables (sqlite_master) by redirecting to IMetadataProvider.
+    /// </summary>
+    private DbDataReader ExecuteSystemTableQuery(string commandTextUpper, CommandBehavior behavior)
+    {
+#if DEBUG
+        System.Diagnostics.Debug.WriteLine($"[ExecuteSystemTableQuery] Query: {CommandText}");
+        System.Diagnostics.Debug.WriteLine($"[ExecuteSystemTableQuery] Command (upper): {commandTextUpper}");
+#endif
+        
+        try
+        {
+            var db = Connection!.DbInstance!;
+            
+            // Check if this is a table list query
+            if (commandTextUpper.Contains("SELECT") && commandTextUpper.Contains("NAME"))
+            {
+#if DEBUG
+                System.Diagnostics.Debug.WriteLine($"[ExecuteSystemTableQuery] Detected table list query");
+                System.Diagnostics.Debug.WriteLine($"[ExecuteSystemTableQuery] Database type: {db.GetType().Name}");
+                System.Diagnostics.Debug.WriteLine($"[ExecuteSystemTableQuery] IMetadataProvider: {db is IMetadataProvider}");
+#endif
+                
+                // Redirect to IMetadataProvider.GetTables()
+                if (db is IMetadataProvider metadata)
+                {
+                    var tables = metadata.GetTables();
+                    
+#if DEBUG
+                    System.Diagnostics.Debug.WriteLine($"[ExecuteSystemTableQuery] GetTables() returned {tables?.Count ?? 0} tables");
+#endif
+                    
+                    // Convert to the format expected by SQLite queries
+                    var results = new List<Dictionary<string, object>>();
+                    
+                    if (tables != null && tables.Count > 0)
+                    {
+                        foreach (var table in tables)
+                        {
+#if DEBUG
+                            System.Diagnostics.Debug.WriteLine($"[ExecuteSystemTableQuery] Table: {table.Name}, Type: {table.Type}");
+#endif
+                            results.Add(new Dictionary<string, object>
+                            {
+                                ["name"] = table.Name ?? string.Empty,
+                                ["type"] = table.Type ?? "TABLE"
+                            });
+                        }
+                    }
+                    
+#if DEBUG
+                    System.Diagnostics.Debug.WriteLine($"[ExecuteSystemTableQuery] Returning {results.Count} rows");
+#endif
+                    
+                    // Return empty result set if no tables (this is valid - new database)
+                    return new SharpCoreDBDataReader(results, behavior);
+                }
+                else
+                {
+#if DEBUG
+                    System.Diagnostics.Debug.WriteLine($"[ExecuteSystemTableQuery] ERROR: Database does not implement IMetadataProvider!");
+#endif
+                }
+            }
+            
+            // Check if this is a column list query (pragma_table_info or similar)
+            if (commandTextUpper.Contains("PRAGMA") || commandTextUpper.Contains("TABLE_INFO"))
+            {
+                // Extract table name from query (simplified parsing)
+                var tableName = ExtractTableNameFromPragma(CommandText!);
+                
+                if (!string.IsNullOrEmpty(tableName) && db is IMetadataProvider metadata)
+                {
+                    var columns = metadata.GetColumns(tableName);
+                    
+                    var results = new List<Dictionary<string, object>>();
+                    foreach (var column in columns)
+                    {
+                        results.Add(new Dictionary<string, object>
+                        {
+                            ["cid"] = column.Ordinal,
+                            ["name"] = column.Name,
+                            ["type"] = column.DataType,
+                            ["notnull"] = !column.IsNullable ? 1 : 0,
+                            ["dflt_value"] = DBNull.Value,
+                            ["pk"] = 0
+                        });
+                    }
+                    
+                    return new SharpCoreDBDataReader(results, behavior);
+                }
+            }
+            
+            // Fallback: Return empty result set for unsupported system queries
+            // This is valid - don't throw an exception
+            return new SharpCoreDBDataReader([], behavior);
+        }
+        catch (Exception ex)
+        {
+            // Log the error but return empty result set instead of crashing
+            System.Diagnostics.Debug.WriteLine($"[SharpCoreDB] System table query failed: {ex.Message}");
+            return new SharpCoreDBDataReader([], behavior);
+        }
+    }
+
+    /// <summary>
+    /// Extracts table name from PRAGMA table_info() or similar queries.
+    /// </summary>
+    private static string? ExtractTableNameFromPragma(string sql)
+    {
+        try
+        {
+            // Simple regex to extract table name from PRAGMA table_info('tablename')
+            var match = System.Text.RegularExpressions.Regex.Match(
+                sql, 
+                @"table_info\s*\(\s*['""]?(\w+)['""]?\s*\)", 
+                System.Text.RegularExpressions.RegexOptions.IgnoreCase);
+            
+            if (match.Success && match.Groups.Count > 1)
+            {
+                return match.Groups[1].Value;
+            }
+            
+            // Try to extract from SELECT * FROM pragma_table_info('tablename')
+            match = System.Text.RegularExpressions.Regex.Match(
+                sql,
+                @"pragma_table_info\s*\(\s*['""]?(\w+)['""]?\s*\)",
+                System.Text.RegularExpressions.RegexOptions.IgnoreCase);
+            
+            if (match.Success && match.Groups.Count > 1)
+            {
+                return match.Groups[1].Value;
+            }
+        }
+        catch
+        {
+            // Ignore parsing errors
+        }
+        
+        return null;
+    }
+
     /// <summary>
     /// Executes a SQL statement and returns the first column of the first row.
     /// </summary>
@@ -224,6 +384,17 @@ public override async Task<int> ExecuteNonQueryAsync(CancellationToken cancellat
             else
                 await db.ExecuteSQLAsync(CommandText!, cancellationToken);
 
+            // ? CRITICAL FIX: Flush data after non-query commands to ensure persistence!
+            // Without this, INSERT/UPDATE/DELETE data only lives in memory until connection close.
+            // This is essential for data durability - we want data on disk IMMEDIATELY.
+            var commandUpper = CommandText!.Trim().ToUpperInvariant();
+            if (commandUpper.StartsWith("INSERT") || 
+                commandUpper.StartsWith("UPDATE") || 
+                commandUpper.StartsWith("DELETE"))
+            {
+                db.Flush();
+            }
+
             return -1;
         }
         catch (Exception ex)
@@ -280,6 +451,13 @@ protected override async Task<DbDataReader> ExecuteDbDataReaderAsync(CommandBeha
             var db = Connection!.DbInstance!;
             var parameters = BuildParameterDictionary();
 
+            // ? FIX: Intercept SQLite system table queries and redirect to IMetadataProvider
+            var commandTextUpper = CommandText!.ToUpperInvariant().Trim();
+            if (commandTextUpper.Contains("SQLITE_MASTER") || commandTextUpper.Contains("SQLITE_SCHEMA"))
+            {
+                return ExecuteSystemTableQuery(commandTextUpper, behavior);
+            }
+
             // ExecuteQuery doesn't have async version, so use Task.Run
             var results = await Task.Run(() =>
             {

SharpCoreDB.Data.Provider/SharpCoreDBConnection.cs

@@ -117,6 +117,17 @@ public override void Open()
         catch (Exception ex)
         {
             _state = ConnectionState.Broken;
+            
+            // ? FIX: Provide clear error message if sqlite_master is mentioned
+            if (ex.Message.Contains("sqlite_master", StringComparison.OrdinalIgnoreCase))
+            {
+                throw new SharpCoreDBException(
+                    "SharpCoreDB is not SQLite. The error 'Table sqlite_master does not exist' indicates that " +
+                    "some tooling or code is trying to query SQLite system tables. " +
+                    "SharpCoreDB uses its own metadata system via IMetadataProvider. " +
+                    $"Original error: {ex.Message}", ex);
+            }
+            
             throw new SharpCoreDBException("Failed to open connection to SharpCoreDB.", ex);
         }
     }
@@ -131,6 +142,23 @@ public override void Close()
 
         try
         {
+            // ? FIX: FORCE save metadata on close to ensure persistence
+            if (_database != null)
+            {
+                try
+                {
+                    _database.ForceSave();
+                }
+                catch (Exception ex)
+                {
+#if DEBUG
+                    System.Diagnostics.Debug.WriteLine($"[SharpCoreDB] Failed to save during close: {ex.Message}");
+#endif
+                    // Suppress exception to allow connection to close gracefully
+                    _ = ex; // Avoid unused variable warning
+                }
+            }
+            
             _database = null;
 
             if (_serviceProvider is IDisposable disposable)

SharpCoreDB.Viewer/App.axaml

@@ -20,6 +20,8 @@
 
     <Application.Styles>
         <FluentTheme />
+        <!-- Include DataGrid styles so it renders headers/rows -->
+        <StyleInclude Source="avares://Avalonia.Controls.DataGrid/Themes/Fluent.xaml"/>
 
         <!-- Custom Visual Studio Dark Theme -->
         <StyleInclude Source="/Styles/VSTheme.axaml"/>

SharpCoreDB.Viewer/Converters/DictionaryValueConverter.cs

@@ -0,0 +1,62 @@
+using Avalonia.Data.Converters;
+using System;
+using System.Collections.Generic;
+using System.Globalization;
+
+namespace SharpCoreDB.Viewer.Converters;
+
+/// <summary>
+/// Converter to extract values from Dictionary<string, object> for DataGrid binding.
+/// </summary>
+public class DictionaryValueConverter : IValueConverter
+{
+    public string? ColumnName { get; set; }
+
+    public object? Convert(object? value, Type targetType, object? parameter, CultureInfo culture)
+    {
+#if DEBUG
+        System.Diagnostics.Debug.WriteLine($"[DictionaryValueConverter] Convert called - value type: {value?.GetType().Name ?? "NULL"}, parameter: {parameter}");
+#endif
+        
+        if (value is Dictionary<string, object> dict)
+        {
+            var key = parameter as string ?? ColumnName;
+            
+#if DEBUG
+            System.Diagnostics.Debug.WriteLine($"[DictionaryValueConverter] Dictionary has {dict.Count} keys, looking for key: '{key}'");
+#endif
+            
+            if (key != null && dict.TryGetValue(key, out var val))
+            {
+#if DEBUG
+                System.Diagnostics.Debug.WriteLine($"[DictionaryValueConverter] Found value: {val} (type: {val?.GetType().Name ?? "NULL"})");
+#endif
+                
+                // Convert DBNull to empty string
+                if (val == DBNull.Value || val == null)
+                    return string.Empty;
+                
+                return val.ToString() ?? string.Empty;
+            }
+            else
+            {
+#if DEBUG
+                System.Diagnostics.Debug.WriteLine($"[DictionaryValueConverter] Key '{key}' NOT FOUND in dictionary. Available keys: {string.Join(", ", dict.Keys)}");
+#endif
+            }
+        }
+        else
+        {
+#if DEBUG
+            System.Diagnostics.Debug.WriteLine($"[DictionaryValueConverter] Value is NOT a Dictionary!");
+#endif
+        }
+        
+        return string.Empty;
+    }
+
+    public object? ConvertBack(object? value, Type targetType, object? parameter, CultureInfo culture)
+    {
+        throw new NotImplementedException();
+    }
+}

SharpCoreDB.Viewer/Converters/ObjectToStringConverter.cs

@@ -0,0 +1,50 @@
+using Avalonia.Data.Converters;
+using System;
+using System.Globalization;
+
+namespace SharpCoreDB.Viewer.Converters;
+
+/// <summary>
+/// Converter to safely convert any object to string for display in DataGrid.
+/// Handles DBNull, null, DateTime, bool, and other types.
+/// </summary>
+public class ObjectToStringConverter : IValueConverter
+{
+    public object? Convert(object? value, Type targetType, object? parameter, CultureInfo culture)
+    {
+#if DEBUG
+        System.Diagnostics.Debug.WriteLine($"[ObjectToStringConverter] Convert called - value type: {value?.GetType().Name ?? "NULL"}, value: {value}");
+#endif
+        
+        if (value == null || value == DBNull.Value)
+            return string.Empty;
+
+        if (value is DateTime dt)
+            return dt.ToString("yyyy-MM-dd HH:mm:ss");
+
+        if (value is bool b)
+            return b ? "1" : "0";
+
+        if (value is decimal dec)
+            return dec.ToString("N2", culture);
+
+        if (value is double dbl)
+            return dbl.ToString("N2", culture);
+
+        if (value is float flt)
+            return flt.ToString("N2", culture);
+
+        var result = value.ToString() ?? string.Empty;
+        
+#if DEBUG
+        System.Diagnostics.Debug.WriteLine($"[ObjectToStringConverter] Returning: '{result}'");
+#endif
+        
+        return result;
+    }
+
+    public object? ConvertBack(object? value, Type targetType, object? parameter, CultureInfo culture)
+    {
+        throw new NotImplementedException();
+    }
+}

SharpCoreDB.Viewer/Converters/PasswordVisibilityConverters.cs

@@ -14,10 +14,10 @@ public static class BoolConverters
     private static readonly LocalizationService _localization = LocalizationService.Instance;
 
     /// <summary>
-    /// Converts boolean to PasswordChar: empty string (visible) or bullet (hidden)
+    /// Converts boolean to PasswordChar: empty string (visible) or asterisk (hidden)
     /// </summary>
     public static readonly IValueConverter PasswordCharConverter = 
-        new FuncValueConverter<bool, char>(isVisible => isVisible ? '\0' : '?');
+        new FuncValueConverter<bool, char>(isVisible => isVisible ? '\0' : '*');
 
     /// <summary>
     /// Converts boolean to Eye icon: EyeIcon (visible) or EyeOffIcon (hidden)