From 290f5492252d992a1208ec3ee537fc5c0c530d12 Mon Sep 17 00:00:00 2001
From: JT <Hawxy@users.noreply.github.com>
Date: Mon, 22 Jul 2024 22:56:31 +0800
Subject: [PATCH] Add GroupedParameterBuilder

---
 src/Weasel.Postgresql/BatchBuilder.cs         | 26 +++++++++++-
 src/Weasel.Postgresql/CommandBuilder.cs       | 19 +++++++--
 .../GroupedParameterBuilder.cs                | 41 +++++++++++++++++++
 src/Weasel.Postgresql/ICommandBuilder.cs      |  4 ++
 4 files changed, 84 insertions(+), 6 deletions(-)
 create mode 100644 src/Weasel.Postgresql/GroupedParameterBuilder.cs

diff --git a/src/Weasel.Postgresql/BatchBuilder.cs b/src/Weasel.Postgresql/BatchBuilder.cs
index ae443bf..b71c252 100644
--- a/src/Weasel.Postgresql/BatchBuilder.cs
+++ b/src/Weasel.Postgresql/BatchBuilder.cs
@@ -65,6 +65,23 @@ public NpgsqlParameter AppendParameter<T>(T value)
         return param;
     }
 
+    public NpgsqlParameter AppendParameter<T>(T value, NpgsqlDbType dbType)
+    {
+        _current ??= appendCommand();
+        var param = new NpgsqlParameter<T>() {
+            TypedValue = value,
+            NpgsqlDbType = dbType
+        };
+
+        _current.Parameters.Add(param);
+
+        _builder.Append('$');
+        _builder.Append(_current.Parameters.Count);
+
+        return param;
+    }
+
+
     public NpgsqlParameter AppendParameter(object value)
     {
         _current ??= appendCommand();
@@ -97,6 +114,11 @@ public void AppendParameters(params object[] parameters)
         }
     }
 
+    public IGroupedParameterBuilder CreateGroupedParameterBuilder(char? seperator = null)
+    {
+        return new GroupedParameterBuilder(this, seperator);
+    }
+
     /// <summary>
     ///     Append a SQL string with user defined placeholder characters for new parameters, and returns an
     ///     array of the newly created parameters
@@ -119,7 +141,7 @@ public NpgsqlParameter[] AppendWithParameters(string text, char placeholder)
         for (var i = 0; i < parameters.Length; i++)
         {
             // Just need a placeholder parameter type and value
-            var parameter = AppendParameter(DBNull.Value, NpgsqlDbType.Text);
+            var parameter = AppendParameter<object>(DBNull.Value, NpgsqlDbType.Text);
             parameters[i] = parameter;
             _builder.Append(split[i + 1]);
         }
@@ -146,7 +168,7 @@ public NpgsqlParameter[] AppendWithParameters(string text, char separator)
             }
 
             // Just need a placeholder parameter type and value
-            var parameter = AppendParameter(DBNull.Value, NpgsqlDbType.Text);
+            var parameter = AppendParameter<object>(DBNull.Value, NpgsqlDbType.Text);
             parameters[pos] = parameter;
             _builder.Append(span[range]);
             pos++;
diff --git a/src/Weasel.Postgresql/CommandBuilder.cs b/src/Weasel.Postgresql/CommandBuilder.cs
index f30ddf5..e556944 100644
--- a/src/Weasel.Postgresql/CommandBuilder.cs
+++ b/src/Weasel.Postgresql/CommandBuilder.cs
@@ -29,24 +29,30 @@ public CommandBuilder(NpgsqlCommand command): base(PostgresqlProvider.Instance,
     /// <param name="dbType"></param>
     public void AppendParameter(string[] values)
     {
-        AppendParameter(values, NpgsqlDbType.Varchar | NpgsqlDbType.Array);
+        base.AppendParameter(values, NpgsqlDbType.Varchar | NpgsqlDbType.Array);
     }
 
     NpgsqlParameter ICommandBuilder.AppendParameter<T>(T value)
     {
-        AppendParameter(value);
+        base.AppendParameter(value);
+        return _command.Parameters[^1];
+    }
+
+    public NpgsqlParameter AppendParameter<T>(T value, NpgsqlDbType dbType)
+    {
+        base.AppendParameter(value, dbType);
         return _command.Parameters[^1];
     }
 
     NpgsqlParameter ICommandBuilder.AppendParameter(object value)
     {
-        AppendParameter(value);
+        base.AppendParameter(value);
         return _command.Parameters[^1];
     }
 
     NpgsqlParameter ICommandBuilder.AppendParameter(object? value, NpgsqlDbType? dbType)
     {
-        AppendParameter(value, dbType);
+        base.AppendParameter(value, dbType);
         return _command.Parameters[^1];
     }
 
@@ -65,6 +71,11 @@ void ICommandBuilder.AppendParameters(params object[] parameters)
         }
     }
 
+    public IGroupedParameterBuilder CreateGroupedParameterBuilder(char? seperator = null)
+    {
+        return new GroupedParameterBuilder(this, seperator);
+    }
+
     public void StartNewCommand()
     {
         // do nothing!
diff --git a/src/Weasel.Postgresql/GroupedParameterBuilder.cs b/src/Weasel.Postgresql/GroupedParameterBuilder.cs
new file mode 100644
index 0000000..17d8b66
--- /dev/null
+++ b/src/Weasel.Postgresql/GroupedParameterBuilder.cs
@@ -0,0 +1,41 @@
+using Npgsql;
+using NpgsqlTypes;
+
+namespace Weasel.Postgresql;
+
+public interface IGroupedParameterBuilder
+{
+    NpgsqlParameter AppendParameter<T>(T? value) where T : notnull;
+    NpgsqlParameter AppendParameter<T>(T? value, NpgsqlDbType dbType) where T : notnull;
+}
+
+public sealed class GroupedParameterBuilder: IGroupedParameterBuilder
+{
+    private readonly ICommandBuilder _commandBuilder;
+    private readonly char? _seperator;
+    private int _count = 0;
+
+    public GroupedParameterBuilder(ICommandBuilder commandBuilder, char? seperator)
+    {
+        _commandBuilder = commandBuilder;
+        _seperator = seperator;
+    }
+
+    public NpgsqlParameter AppendParameter<T>(T? value) where T : notnull
+    {
+        if(_count > 0 && _seperator.HasValue)
+            _commandBuilder.Append(_seperator.Value);
+
+        _count++;
+        return _commandBuilder.AppendParameter(value);
+    }
+
+    public NpgsqlParameter AppendParameter<T>(T? value, NpgsqlDbType dbType) where T : notnull
+    {
+        if(_count > 0 && _seperator.HasValue)
+            _commandBuilder.Append(_seperator.Value);
+
+        _count++;
+        return _commandBuilder.AppendParameter(value, dbType);
+    }
+}
diff --git a/src/Weasel.Postgresql/ICommandBuilder.cs b/src/Weasel.Postgresql/ICommandBuilder.cs
index d8ff9fd..791acf7 100644
--- a/src/Weasel.Postgresql/ICommandBuilder.cs
+++ b/src/Weasel.Postgresql/ICommandBuilder.cs
@@ -18,11 +18,15 @@ public interface ICommandBuilder
 
     void Append(string sql);
     void Append(char character);
+
     NpgsqlParameter AppendParameter<T>(T value);
+    NpgsqlParameter AppendParameter<T>(T value, NpgsqlDbType dbType);
     NpgsqlParameter AppendParameter(object value);
     NpgsqlParameter AppendParameter(object? value, NpgsqlDbType? dbType);
     void AppendParameters(params object[] parameters);
 
+    IGroupedParameterBuilder CreateGroupedParameterBuilder(char? seperator = null);
+
     /// <summary>
     ///     Append a SQL string with user defined placeholder characters for new parameters, and returns an
     ///     array of the newly created parameters