From 1840d119def14731fbbb914de0f67d53516c45bc Mon Sep 17 00:00:00 2001
From: Luca Maccarini <lucamaccarini22@gmail.com>
Date: Sun, 29 Jun 2025 18:30:30 +0200
Subject: [PATCH 1/4] add Llama.mobile code containing a basic chatbot

---
 .gitignore                                    |   3 +-
 LLamaSharp.sln                                |  21 +++
 Llama.Mobile/MainPage.xaml                    | 112 +++++++++++--
 Llama.Mobile/MainPage.xaml.cs                 | 152 +++++++++++++++++-
 .../Src/ChatMessageTemplateSelector.cs        |  16 ++
 Llama.Mobile/Src/InverseBooleanConverter.cs   |  25 +++
 Llama.Mobile/Src/Message.cs                   |  63 ++++++++
 7 files changed, 377 insertions(+), 15 deletions(-)
 create mode 100644 Llama.Mobile/Src/ChatMessageTemplateSelector.cs
 create mode 100644 Llama.Mobile/Src/InverseBooleanConverter.cs
 create mode 100644 Llama.Mobile/Src/Message.cs

diff --git a/.gitignore b/.gitignore
index 206b0dac1..ac50b1485 100644
--- a/.gitignore
+++ b/.gitignore
@@ -351,4 +351,5 @@ site/
 **/appsettings.Local.json
 /LLama/runtimes/deps
 /LLama/runtimes/deps.zip
-/LLama/runtimes/release_id.txt
\ No newline at end of file
+/LLama/runtimes/release_id.txt
+/Llama.Mobile/Resources/Raw/Llama-3.2-1B-Instruct-Q4_0.gguf
diff --git a/LLamaSharp.sln b/LLamaSharp.sln
index 7c970aa99..e18363591 100644
--- a/LLamaSharp.sln
+++ b/LLamaSharp.sln
@@ -21,6 +21,8 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "LLama.Experimental", "LLama
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "LLama.Benchmark", "LLama.Benchmark\LLama.Benchmark.csproj", "{90D38FEE-68EA-459E-A4EE-268B9DFA1CD5}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Llama.Mobile", "Llama.Mobile\Llama.Mobile.csproj", "{0E058BB0-83C6-4FBE-BC80-E8C5F7E29651}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -196,6 +198,25 @@ Global
 		{90D38FEE-68EA-459E-A4EE-268B9DFA1CD5}.Release|Arm64.Build.0 = Release|Any CPU
 		{90D38FEE-68EA-459E-A4EE-268B9DFA1CD5}.Release|x64.ActiveCfg = Release|Any CPU
 		{90D38FEE-68EA-459E-A4EE-268B9DFA1CD5}.Release|x64.Build.0 = Release|Any CPU
+		{0E058BB0-83C6-4FBE-BC80-E8C5F7E29651}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{0E058BB0-83C6-4FBE-BC80-E8C5F7E29651}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{0E058BB0-83C6-4FBE-BC80-E8C5F7E29651}.Debug|Any CPU.Deploy.0 = Debug|Any CPU
+		{0E058BB0-83C6-4FBE-BC80-E8C5F7E29651}.Debug|Arm64.ActiveCfg = Debug|Any CPU
+		{0E058BB0-83C6-4FBE-BC80-E8C5F7E29651}.Debug|Arm64.Build.0 = Debug|Any CPU
+		{0E058BB0-83C6-4FBE-BC80-E8C5F7E29651}.Debug|x64.ActiveCfg = Debug|Any CPU
+		{0E058BB0-83C6-4FBE-BC80-E8C5F7E29651}.Debug|x64.Build.0 = Debug|Any CPU
+		{0E058BB0-83C6-4FBE-BC80-E8C5F7E29651}.GPU|Any CPU.ActiveCfg = Debug|Any CPU
+		{0E058BB0-83C6-4FBE-BC80-E8C5F7E29651}.GPU|Any CPU.Build.0 = Debug|Any CPU
+		{0E058BB0-83C6-4FBE-BC80-E8C5F7E29651}.GPU|Arm64.ActiveCfg = Debug|Any CPU
+		{0E058BB0-83C6-4FBE-BC80-E8C5F7E29651}.GPU|Arm64.Build.0 = Debug|Any CPU
+		{0E058BB0-83C6-4FBE-BC80-E8C5F7E29651}.GPU|x64.ActiveCfg = Debug|Any CPU
+		{0E058BB0-83C6-4FBE-BC80-E8C5F7E29651}.GPU|x64.Build.0 = Debug|Any CPU
+		{0E058BB0-83C6-4FBE-BC80-E8C5F7E29651}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{0E058BB0-83C6-4FBE-BC80-E8C5F7E29651}.Release|Any CPU.Build.0 = Release|Any CPU
+		{0E058BB0-83C6-4FBE-BC80-E8C5F7E29651}.Release|Arm64.ActiveCfg = Release|Any CPU
+		{0E058BB0-83C6-4FBE-BC80-E8C5F7E29651}.Release|Arm64.Build.0 = Release|Any CPU
+		{0E058BB0-83C6-4FBE-BC80-E8C5F7E29651}.Release|x64.ActiveCfg = Release|Any CPU
+		{0E058BB0-83C6-4FBE-BC80-E8C5F7E29651}.Release|x64.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
diff --git a/Llama.Mobile/MainPage.xaml b/Llama.Mobile/MainPage.xaml
index 5bd8e7e94..31215a8c9 100644
--- a/Llama.Mobile/MainPage.xaml
+++ b/Llama.Mobile/MainPage.xaml
@@ -1,14 +1,106 @@
 <?xml version="1.0" encoding="utf-8" ?>
 
-<ContentPage xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
-             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
-             x:Class="Llama.Mobile.MainPage">
-    <Label
-        x:Name="label1"
-        Text="Hello, World!"
-        Style="{StaticResource Headline}"
-        HorizontalOptions="Center"
-        VerticalOptions="Center"
-        SemanticProperties.HeadingLevel="Level1" />
+<ContentPage xmlns="http://schemas.microsoft.com/dotnet/2021/maui"  
+            xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"  
+            x:Class="Llama.Mobile.MainPage"  
+            Title="Bob, the AI assisant"  
+            xmlns:src="clr-namespace:Llama.Mobile.Src"  
+            >  
+
+   <ContentPage.Resources>  
+       <src:InverseBooleanConverter x:Key="InverseBooleanConverter"/>  
+
+       <DataTemplate x:Key="UserMessageTemplate">  
+           <Grid ColumnDefinitions="*,auto">  
+               <Frame BackgroundColor="LightBlue"  
+                      Padding="10"  
+                      CornerRadius="16"  
+                      HasShadow="False"  
+                      Margin="40,4,4,4"  
+                      HorizontalOptions="End"  
+                      BorderColor="#B0C4DE">  
+                   <Label Text="{Binding Text}" TextColor="Black"/>  
+               </Frame>  
+               <BoxView Grid.Column="1"  
+                        WidthRequest="10"  
+                        HeightRequest="10"  
+                        BackgroundColor="LightBlue"  
+                        CornerRadius="10,10,10,10"  
+                        Margin="0,0,8,8"  
+                        VerticalOptions="End"  
+                        HorizontalOptions="End"/>  
+           </Grid>  
+       </DataTemplate>  
+       <DataTemplate x:Key="OtherMessageTemplate">  
+           <Grid ColumnDefinitions="auto,*">  
+               <BoxView Grid.Column="0"  
+                        WidthRequest="10"  
+                        HeightRequest="10"  
+                        BackgroundColor="LightGray"  
+                        CornerRadius="10,10,10,10"  
+                        Margin="8,0,0,8"  
+                        VerticalOptions="End"  
+                        HorizontalOptions="Start"/>  
+               <Frame Grid.Column="1"  
+                      BackgroundColor="LightGray"  
+                      Padding="10"  
+                      CornerRadius="16"  
+                      HasShadow="False"  
+                      Margin="4,4,40,4"  
+                      HorizontalOptions="Start"  
+                      BorderColor="#D3D3D3">  
+                   <Grid>  
+                       <Label Text="{Binding Text}" TextColor="Black" IsVisible="{Binding IsPreparing, Converter={StaticResource InverseBooleanConverter}}" />  
+                       <ActivityIndicator IsRunning="True" IsVisible="{Binding IsPreparing}" WidthRequest="20" HeightRequest="20" />  
+                   </Grid>  
+               </Frame>  
+           </Grid>  
+       </DataTemplate>  
+
+       <src:ChatMessageTemplateSelector x:Key="ChatTemplateSelector"  
+                                     UserTemplate="{StaticResource UserMessageTemplate}"  
+                                     OtherTemplate="{StaticResource OtherMessageTemplate}" />  
+   </ContentPage.Resources>  
+
+   <Grid RowDefinitions="Auto,*,Auto,Auto">  
+       <HorizontalStackLayout Grid.Row="0" x:Name="pn_loading">  
+           <Label  
+           Text="Loading the model"  
+           VerticalOptions="Center"  
+           HorizontalOptions="StartAndExpand"/>  
+           <ActivityIndicator  
+           IsRunning="True"  
+           IsVisible="True"  
+           WidthRequest="25"  
+           HeightRequest="25"  
+           VerticalOptions="Center"  
+           HorizontalOptions="EndAndExpand"/>  
+       </HorizontalStackLayout>  
+
+       <CollectionView  
+       ItemsSource="{Binding Messages}"  
+       ItemTemplate="{StaticResource ChatTemplateSelector}"  
+       x:Name="chat"  
+       Grid.Row="1"  
+       VerticalOptions="FillAndExpand">  
+           <CollectionView.ItemsLayout>  
+               <LinearItemsLayout Orientation="Vertical"/>  
+           </CollectionView.ItemsLayout>  
+       </CollectionView>  
+
+       <Entry  
+        x:Name="tx_userPrompt"  
+        Placeholder="Ask to the model"  
+        Margin="10"  
+        Grid.Row="2"/>  
+
+       <Button   
+        x:Name="btn_ask"  
+        Text="Ask"  
+        Clicked="OnAskClicked"  
+        IsEnabled="False"  
+        Margin="10,0,10,10"  
+        Grid.Row="3"/>  
+   </Grid>  
 
 </ContentPage>
\ No newline at end of file
diff --git a/Llama.Mobile/MainPage.xaml.cs b/Llama.Mobile/MainPage.xaml.cs
index 8c9cb310c..a9f9fd2ee 100644
--- a/Llama.Mobile/MainPage.xaml.cs
+++ b/Llama.Mobile/MainPage.xaml.cs
@@ -1,16 +1,160 @@
 namespace Llama.Mobile;
 
+using Android.Icu.Text;
+using Java.Lang;
+using Javax.Annotation;
+using Llama.Mobile.Src;
+using LLama;
+using LLama.Common;
 using LLama.Native;
+using LLama.Sampling;
+using System.Collections.ObjectModel;
+using System.Text;
+using System.Xml.Linq;
+using Xamarin.Google.Crypto.Tink.Subtle;
+using Xamarin.KotlinX.Coroutines;
+using static System.Net.Mime.MediaTypeNames;
+using StringBuilder = System.Text.StringBuilder;
 
 public partial class MainPage : ContentPage
 {
-    public MainPage()
+
+    public ObservableCollection<Message> Messages { get; } = new();
+
+    //put the gguf model in rasources/raw
+    private const string modelName = "Llama-3.2-1B-Instruct-Q4_0.gguf";
+
+    private ChatSession? _session;
+    ChatSession Session
+    {
+        get
+        {
+            if (_session is null) throw new NullReferenceException("_session can't be null");
+            return _session;
+        }
+
+        set
+        {
+            _session = value;
+        }
+    }
+
+    private static InferenceParams InferenceParams = new InferenceParams()
+    {
+        MaxTokens = 256, // No more than 256 tokens should appear in answer. Remove it if antiprompt is enough for control.
+        AntiPrompts = new List<string> { "User:" }, // Stop generation once antiprompts appear.
+
+        SamplingPipeline = new DefaultSamplingPipeline(),
+
+    };
+
+public MainPage()
     {
         InitializeComponent();
+        chat.BindingContext = this;
+    }
+    protected override async void OnAppearing()
+    {
+        base.OnAppearing();
+        string modelPath = Path.Combine(FileSystem.Current.AppDataDirectory, modelName);
+
+        if (!File.Exists(modelPath))
+        {
+            //get a stream of the model stored in the apk
+            using Stream inputStream = await FileSystem.Current.OpenAppPackageFileAsync(modelName);
+
+            //copy the data from the inputStream in to a file, with te same name, in the the app data directory
+            using FileStream outputStream = File.Create(modelPath);
+            await inputStream.CopyToAsync(outputStream);
+            outputStream.Close();
+            inputStream.Close();
+        }
+
+
+        var parameters = new ModelParams(modelPath)
+        {
+            ContextSize = 1024, // The longest length of chat as memory.
+            GpuLayerCount = 5 // How many layers to offload to GPU. Please adjust it according to your GPU memory.
+        };
+        var model = LLamaWeights.LoadFromFile(parameters);
+        var context = model.CreateContext(parameters);
+        var executor = new InteractiveExecutor(context);
+
+        // Add chat histories as prompt to tell AI how to act.
+        var chatHistory = new ChatHistory();
+        chatHistory.AddMessage(AuthorRole.System, "Transcript of a dialog, where the User interacts with an Assistant named Bob. Bob is helpful, kind, honest, good at writing, and never fails to answer the User's requests immediately and with precision.");
+        chatHistory.AddMessage(AuthorRole.User, "Hello, Bob.");
+        chatHistory.AddMessage(AuthorRole.Assistant, "Hello. How may I help you today?");
+
+        Session = new(executor, chatHistory);
+
+        pn_loading.IsVisible = false;
+        btn_ask.IsEnabled = true;
+
+        await Task.Delay(100); //on the emulator without this little delay the popup isn't shown
+
+        await DisplayAlert("Loaded", "model correctly Loaded", "OK");
+    }
+
+    private async void OnAskClicked(object sender, EventArgs e)
+    {
+        btn_ask.IsEnabled = false;
+        Messages.Add(new Message { Type = messageType.User, Text = tx_userPrompt.Text, IsPreparing = false });
+        Message response = new Message { Type = messageType.other, Text = "", IsPreparing = true };
+        Messages.Add(response);
+        chat.ScrollTo(Messages.Last(), position: ScrollToPosition.End, animate: false);
+
+        StringBuilder sp = new StringBuilder();
+        bool assistantHeaderRemoved = false;
+        bool userRemoved = false;
+        await foreach (string text in Session.ChatAsync(new ChatHistory.Message(AuthorRole.User, tx_userPrompt.Text), InferenceParams))
+        {
+            //raw model output cleaning from words like "Assistant:" and "User:"
+            //if your model produces a clean output you can just only leave the following two instruction
+            //inside this loop:
+            //response.IsPreparing = false;
+            //response.AppendText(text); 
+
+            if (!assistantHeaderRemoved)
+            {
+                sp.Append(text);
+                if (sp.Length >= 11)
+                {
+                    sp = sp.Remove(0, 11);
+                    assistantHeaderRemoved = true;
+                    response.Text = sp.ToString();
+                    response.IsPreparing = false;
+                    sp.Clear();
+                }
+                continue;
+            }
+
+            if (text.EndsWith("User"))
+            {
+                response.AppendText(text.Remove(text.Length - 4));
+                userRemoved = true;
+            }
+            else if (userRemoved)
+            {
+                if (text == ":")
+                {
+                    break;
+                }
+                else
+                {
+                    response.AppendText("User" + text);
+                    userRemoved = false;
+                }
 
-        //Load the native library
-        NativeApi.llama_empty_call();
+            }
+            else
+            {
+                response.AppendText(text);
+            }
 
-        label1.Text = "llama.cpp loaded successfully";
+            chat.ScrollTo(Messages.Last(), position: ScrollToPosition.End, animate: false);
+        }
+        response.Text = response.Text.TrimEnd('\n');
+        btn_ask.IsEnabled = true;
     }
 }
diff --git a/Llama.Mobile/Src/ChatMessageTemplateSelector.cs b/Llama.Mobile/Src/ChatMessageTemplateSelector.cs
new file mode 100644
index 000000000..00ded87bf
--- /dev/null
+++ b/Llama.Mobile/Src/ChatMessageTemplateSelector.cs
@@ -0,0 +1,16 @@
+using Microsoft.Maui.Controls;
+namespace Llama.Mobile.Src
+{
+    public class ChatMessageTemplateSelector : DataTemplateSelector
+    {
+        public DataTemplate UserTemplate { get; set; }
+        public DataTemplate OtherTemplate { get; set; }
+
+
+        protected override DataTemplate OnSelectTemplate(object item, BindableObject container)
+        {
+            var message = (Message)item;
+            return message.Type == messageType.User ? UserTemplate : OtherTemplate;
+        }
+    }
+}
diff --git a/Llama.Mobile/Src/InverseBooleanConverter.cs b/Llama.Mobile/Src/InverseBooleanConverter.cs
new file mode 100644
index 000000000..366426afa
--- /dev/null
+++ b/Llama.Mobile/Src/InverseBooleanConverter.cs
@@ -0,0 +1,25 @@
+using System;
+using System.Collections.Generic;
+using System.Globalization;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Llama.Mobile.Src
+{
+    public class InverseBooleanConverter : IValueConverter
+    {
+        public object? Convert(object? value, Type targetType, object? parameter, CultureInfo culture)
+        {
+            if (value is bool boolValue)
+                return !boolValue;
+            else
+                throw new InvalidOperationException("The target must be a boolean");
+        }
+
+        public object? ConvertBack(object? value, Type targetType, object? parameter, CultureInfo culture)
+        {
+            throw new NotSupportedException();
+        }
+    }
+}
diff --git a/Llama.Mobile/Src/Message.cs b/Llama.Mobile/Src/Message.cs
new file mode 100644
index 000000000..b05f84c3e
--- /dev/null
+++ b/Llama.Mobile/Src/Message.cs
@@ -0,0 +1,63 @@
+using Android.Content;
+using System;
+using System.Collections.Generic;
+using System.ComponentModel;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Llama.Mobile.Src
+{
+
+    public enum messageType
+    {
+        User,
+        other,
+    }
+
+    public class Message : INotifyPropertyChanged
+    {
+        private StringBuilder _textBuilder = new StringBuilder();
+        public string Text { 
+            get => _textBuilder.ToString(); 
+            set{
+                _textBuilder = new StringBuilder(value);
+                OnPropertyChanged(nameof(Text));
+            } 
+        }
+        public void AppendText(string text)
+        {
+            _textBuilder.Append(text);
+            OnPropertyChanged(nameof(Text));
+        }
+
+        private bool _isPreparing;
+        public bool IsPreparing
+        {
+            get => _isPreparing;
+            set
+            {
+                if (_isPreparing != value)
+                {
+                    _isPreparing = value;
+                    OnPropertyChanged(nameof(IsPreparing));
+                }
+            }
+        }
+
+        public required messageType Type { get; set; }
+
+
+
+        public event PropertyChangedEventHandler? PropertyChanged;
+
+        protected virtual void OnPropertyChanged(string propertyName)
+        {
+            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
+        }
+    }
+
+
+
+
+}

From acf32335c59f467b9082c3b22e0b9994af53dfbc Mon Sep 17 00:00:00 2001
From: Luca Maccarini <lucamaccarini22@gmail.com>
Date: Wed, 2 Jul 2025 20:38:47 +0200
Subject: [PATCH 2/4] - fix "User:" and "Assistant" removal from model's output
 - added auto download of the model when missing

---
 Llama.Mobile/Llama.Mobile.csproj | 61 ++++++++++++++++++++++++++++++--
 Llama.Mobile/MainPage.xaml.cs    | 59 +++++-------------------------
 2 files changed, 68 insertions(+), 52 deletions(-)

diff --git a/Llama.Mobile/Llama.Mobile.csproj b/Llama.Mobile/Llama.Mobile.csproj
index a51a3eb0f..450cbcf1c 100644
--- a/Llama.Mobile/Llama.Mobile.csproj
+++ b/Llama.Mobile/Llama.Mobile.csproj
@@ -13,7 +13,7 @@
 
     <PropertyGroup>
         <TargetFrameworks>net8.0-android</TargetFrameworks>
-        
+
         <!--Temporarily Disable iOS and MacCatalyst until native lib support is added-->
         <!--<TargetFrameworks>$(TargetFrameworks);net8.0-ios;net8.0-maccatalyst</TargetFrameworks>-->
 
@@ -51,7 +51,64 @@
         <SupportedOSPlatformVersion Condition="$([MSBuild]::GetTargetPlatformIdentifier('$(TargetFramework)')) == 'tizen'">6.5</SupportedOSPlatformVersion>
     </PropertyGroup>
 
+    <Target Name="EnsureFolders">
+        <MakeDir Directories="Resources\Raw" Condition="!Exists('Resources\Raw')" />
+    </Target>
+
+    <!-- Download a single file:
+       - Computes the full target file name (DesiredFile).
+       - If DesiredFile already exists, the download is skipped.
+       - Otherwise, creates a temporary folder (TempDownload), 
+         downloads the file there using DownloadFile, and then moves it
+         to DesiredFile. Finally, cleans up the temporary folder.  -->
+    <Target Name="DownloadSingleFile" DependsOnTargets="EnsureFolders">
+        <!-- (These properties come in via the MSBuild call.) -->
+        <PropertyGroup>
+            <DesiredFile>$([System.IO.Path]::Combine($(DestinationFolder), $(LocalFileName)))</DesiredFile>
+        </PropertyGroup>
+
+        <Message Text="Processing file: $(DesiredFile)" Importance="high" />
+
+        <!-- Define a flag based on whether the file already exists -->
+        <PropertyGroup>
+            <DownloadNeeded Condition="!Exists('$(DesiredFile)')">true</DownloadNeeded>
+            <DownloadNeeded Condition="Exists('$(DesiredFile)')">false</DownloadNeeded>
+        </PropertyGroup>
+        <Message Text="Download needed: $(DownloadNeeded)" Importance="high" />
+
+        <!-- If the file is already present, skip the download (by simply exiting this target) -->
+        <Message Text="File $(DesiredFile) already exists; skipping download." Importance="high" Condition=" '$(DownloadNeeded)'=='false' " />
+
+        <!-- Only download if required -->
+        <DownloadFile SourceUrl="$(SourceUrl)" DestinationFolder="TempDownload" SkipUnchangedFiles="true" Condition=" '$(DownloadNeeded)'=='true' " />
+
+        <!-- If a file was downloaded, move it to the desired name.
+         We assume TempDownload now contains the downloaded file.
+         (You might want to refine this if TempDownload could ever contain multiple files.) -->
+        <ItemGroup Condition=" '$(DownloadNeeded)'=='true' ">
+            <TempFile Include="TempDownload/*.*" />
+        </ItemGroup>
+        <Message Text="Downloaded file (temp): @(TempFile)" Importance="high" Condition=" '$(DownloadNeeded)'=='true' " />
+        <Move SourceFiles="@(TempFile)" DestinationFiles="$(DesiredFile)" Condition=" '$(DownloadNeeded)'=='true' and @(TempFile) != '' " />
+        <Message Text="Renamed downloaded file to $(DesiredFile)" Importance="high" Condition=" '$(DownloadNeeded)'=='true' and @(TempFile) != '' " />
+
+        <!-- Remove the temporary download folder -->
+        <RemoveDir Directories="TempDownload" Condition="Exists('TempDownload')" />
+    </Target>
+
+    <!-- Main target to process each file by calling the DownloadSingleFile target for each item.
+       The MSBuild task will batch over the DownloadFileItem items, passing in each file’s metadata. -->
+    <Target Name="DownloadAllFiles" BeforeTargets="DispatchToInnerBuilds;BeforeBuild">
+        <MSBuild Projects="$(MSBuildProjectFile)" Targets="DownloadSingleFile" Properties="SourceUrl=%(DownloadFileItem.SourceUrl);DestinationFolder=%(DownloadFileItem.DestinationFolder);LocalFileName=%(DownloadFileItem.LocalFileName);TargetFramework=once" />
+    </Target>
+
     <ItemGroup>
+        <DownloadFileItem Include="Llama-3.2-1B-Instruct-Q4_0">
+            <SourceUrl>https://huggingface.co/bartowski/Llama-3.2-1B-Instruct-GGUF/resolve/main/Llama-3.2-1B-Instruct-Q4_0.gguf</SourceUrl>
+            <DestinationFolder>Resources/Raw</DestinationFolder>
+            <LocalFileName>Llama-3.2-1B-Instruct-Q4_0.gguf</LocalFileName>
+        </DownloadFileItem>
+
         <!-- App Icon -->
         <MauiIcon Include="Resources\AppIcon\appicon.svg" ForegroundFile="Resources\AppIcon\appiconfg.svg" Color="#512BD4" />
 
@@ -76,7 +133,7 @@
     </ItemGroup>
 
     <ItemGroup>
-      <ProjectReference Include="..\LLama\LLamaSharp.csproj" />
+        <ProjectReference Include="..\LLama\LLamaSharp.csproj" />
     </ItemGroup>
 
 </Project>
diff --git a/Llama.Mobile/MainPage.xaml.cs b/Llama.Mobile/MainPage.xaml.cs
index a9f9fd2ee..f0e49a49d 100644
--- a/Llama.Mobile/MainPage.xaml.cs
+++ b/Llama.Mobile/MainPage.xaml.cs
@@ -21,7 +21,7 @@ public partial class MainPage : ContentPage
 
     public ObservableCollection<Message> Messages { get; } = new();
 
-    //put the gguf model in rasources/raw
+    //Put the gguf model in the directory resources/raw and write its name in the following string
     private const string modelName = "Llama-3.2-1B-Instruct-Q4_0.gguf";
 
     private ChatSession? _session;
@@ -60,10 +60,10 @@ protected override async void OnAppearing()
 
         if (!File.Exists(modelPath))
         {
-            //get a stream of the model stored in the apk
+            //get the data stream of the model stored in the apk
             using Stream inputStream = await FileSystem.Current.OpenAppPackageFileAsync(modelName);
 
-            //copy the data from the inputStream in to a file, with te same name, in the the app data directory
+            //copy the data from the inputStream in to a new file, with te same name, in the the app data directory
             using FileStream outputStream = File.Create(modelPath);
             await inputStream.CopyToAsync(outputStream);
             outputStream.Close();
@@ -87,6 +87,9 @@ protected override async void OnAppearing()
         chatHistory.AddMessage(AuthorRole.Assistant, "Hello. How may I help you today?");
 
         Session = new(executor, chatHistory);
+        Session.WithOutputTransform(new LLamaTransforms.KeywordTextOutputStreamTransform(
+            new string[] { "\n\nUser:", "\nUser:", "User:", "Assistant: " },
+            redundancyLength: 8));
 
         pn_loading.IsVisible = false;
         btn_ask.IsEnabled = true;
@@ -100,61 +103,17 @@ private async void OnAskClicked(object sender, EventArgs e)
     {
         btn_ask.IsEnabled = false;
         Messages.Add(new Message { Type = messageType.User, Text = tx_userPrompt.Text, IsPreparing = false });
+        tx_userPrompt.Text="";
         Message response = new Message { Type = messageType.other, Text = "", IsPreparing = true };
         Messages.Add(response);
         chat.ScrollTo(Messages.Last(), position: ScrollToPosition.End, animate: false);
 
-        StringBuilder sp = new StringBuilder();
-        bool assistantHeaderRemoved = false;
-        bool userRemoved = false;
         await foreach (string text in Session.ChatAsync(new ChatHistory.Message(AuthorRole.User, tx_userPrompt.Text), InferenceParams))
         {
-            //raw model output cleaning from words like "Assistant:" and "User:"
-            //if your model produces a clean output you can just only leave the following two instruction
-            //inside this loop:
-            //response.IsPreparing = false;
-            //response.AppendText(text); 
-
-            if (!assistantHeaderRemoved)
-            {
-                sp.Append(text);
-                if (sp.Length >= 11)
-                {
-                    sp = sp.Remove(0, 11);
-                    assistantHeaderRemoved = true;
-                    response.Text = sp.ToString();
-                    response.IsPreparing = false;
-                    sp.Clear();
-                }
-                continue;
-            }
-
-            if (text.EndsWith("User"))
-            {
-                response.AppendText(text.Remove(text.Length - 4));
-                userRemoved = true;
-            }
-            else if (userRemoved)
-            {
-                if (text == ":")
-                {
-                    break;
-                }
-                else
-                {
-                    response.AppendText("User" + text);
-                    userRemoved = false;
-                }
-
-            }
-            else
-            {
-                response.AppendText(text);
-            }
-
+            response.IsPreparing = false;
+            response.AppendText(text); 
             chat.ScrollTo(Messages.Last(), position: ScrollToPosition.End, animate: false);
         }
-        response.Text = response.Text.TrimEnd('\n');
         btn_ask.IsEnabled = true;
     }
 }

From f2d6756681960037f8cdb6698958f8363ca32d46 Mon Sep 17 00:00:00 2001
From: Luca Maccarini <lucamaccarini22@gmail.com>
Date: Wed, 2 Jul 2025 22:19:59 +0200
Subject: [PATCH 3/4] Fix UI

---
 Llama.Mobile/MainPage.xaml    | 116 ++++++++++++++++++----------------
 Llama.Mobile/MainPage.xaml.cs |   4 +-
 2 files changed, 62 insertions(+), 58 deletions(-)

diff --git a/Llama.Mobile/MainPage.xaml b/Llama.Mobile/MainPage.xaml
index 31215a8c9..9c8a6a9f4 100644
--- a/Llama.Mobile/MainPage.xaml
+++ b/Llama.Mobile/MainPage.xaml
@@ -5,102 +5,106 @@
             x:Class="Llama.Mobile.MainPage"  
             Title="Bob, the AI assisant"  
             xmlns:src="clr-namespace:Llama.Mobile.Src"  
-            >  
+            >
 
-   <ContentPage.Resources>  
-       <src:InverseBooleanConverter x:Key="InverseBooleanConverter"/>  
+    <ContentPage.Resources>
+        <src:InverseBooleanConverter x:Key="InverseBooleanConverter"/>
 
-       <DataTemplate x:Key="UserMessageTemplate">  
-           <Grid ColumnDefinitions="*,auto">  
-               <Frame BackgroundColor="LightBlue"  
+        <DataTemplate x:Key="UserMessageTemplate">
+            <Grid ColumnDefinitions="*,auto">
+                <Frame BackgroundColor="LightBlue"  
                       Padding="10"  
                       CornerRadius="16"  
                       HasShadow="False"  
                       Margin="40,4,4,4"  
                       HorizontalOptions="End"  
-                      BorderColor="#B0C4DE">  
-                   <Label Text="{Binding Text}" TextColor="Black"/>  
-               </Frame>  
-               <BoxView Grid.Column="1"  
+                      BorderColor="#B0C4DE">
+                    <Label Text="{Binding Text}" TextColor="Black"/>
+                </Frame>
+                <BoxView Grid.Column="1"  
                         WidthRequest="10"  
                         HeightRequest="10"  
                         BackgroundColor="LightBlue"  
                         CornerRadius="10,10,10,10"  
-                        Margin="0,0,8,8"  
+                        Margin="0,0,0,8"  
                         VerticalOptions="End"  
-                        HorizontalOptions="End"/>  
-           </Grid>  
-       </DataTemplate>  
-       <DataTemplate x:Key="OtherMessageTemplate">  
-           <Grid ColumnDefinitions="auto,*">  
-               <BoxView Grid.Column="0"  
+                        HorizontalOptions="End"/>
+            </Grid>
+        </DataTemplate>
+        <DataTemplate x:Key="OtherMessageTemplate">
+            <Grid ColumnDefinitions="auto,*">
+                <BoxView Grid.Column="0"  
                         WidthRequest="10"  
                         HeightRequest="10"  
                         BackgroundColor="LightGray"  
                         CornerRadius="10,10,10,10"  
-                        Margin="8,0,0,8"  
+                        Margin="0,0,0,8"  
                         VerticalOptions="End"  
-                        HorizontalOptions="Start"/>  
-               <Frame Grid.Column="1"  
+                        HorizontalOptions="Start"/>
+                <Frame Grid.Column="1"  
                       BackgroundColor="LightGray"  
                       Padding="10"  
                       CornerRadius="16"  
                       HasShadow="False"  
                       Margin="4,4,40,4"  
                       HorizontalOptions="Start"  
-                      BorderColor="#D3D3D3">  
-                   <Grid>  
-                       <Label Text="{Binding Text}" TextColor="Black" IsVisible="{Binding IsPreparing, Converter={StaticResource InverseBooleanConverter}}" />  
-                       <ActivityIndicator IsRunning="True" IsVisible="{Binding IsPreparing}" WidthRequest="20" HeightRequest="20" />  
-                   </Grid>  
-               </Frame>  
-           </Grid>  
-       </DataTemplate>  
+                      BorderColor="#D3D3D3">
+                    <Grid>
+                        <Label Text="{Binding Text}" TextColor="Black" IsVisible="{Binding IsPreparing, Converter={StaticResource InverseBooleanConverter}}" />
+                        <ActivityIndicator IsRunning="True" IsVisible="{Binding IsPreparing}" WidthRequest="20" HeightRequest="20" />
+                    </Grid>
+                </Frame>
+            </Grid>
+        </DataTemplate>
 
-       <src:ChatMessageTemplateSelector x:Key="ChatTemplateSelector"  
+        <src:ChatMessageTemplateSelector x:Key="ChatTemplateSelector"  
                                      UserTemplate="{StaticResource UserMessageTemplate}"  
-                                     OtherTemplate="{StaticResource OtherMessageTemplate}" />  
-   </ContentPage.Resources>  
+                                     OtherTemplate="{StaticResource OtherMessageTemplate}" />
+    </ContentPage.Resources>
 
-   <Grid RowDefinitions="Auto,*,Auto,Auto">  
-       <HorizontalStackLayout Grid.Row="0" x:Name="pn_loading">  
-           <Label  
+    <Grid RowDefinitions="Auto,*,Auto" Margin="10,0,10,0">
+        <HorizontalStackLayout Grid.Row="0" x:Name="pn_loading">
+            <Label  
            Text="Loading the model"  
            VerticalOptions="Center"  
-           HorizontalOptions="StartAndExpand"/>  
+           HorizontalOptions="StartAndExpand"/>
            <ActivityIndicator  
+           Margin="5,0,0,0"
            IsRunning="True"  
            IsVisible="True"  
            WidthRequest="25"  
            HeightRequest="25"  
            VerticalOptions="Center"  
-           HorizontalOptions="EndAndExpand"/>  
-       </HorizontalStackLayout>  
+           HorizontalOptions="EndAndExpand"/>
+        </HorizontalStackLayout>
 
-       <CollectionView  
+        <CollectionView  
        ItemsSource="{Binding Messages}"  
        ItemTemplate="{StaticResource ChatTemplateSelector}"  
        x:Name="chat"  
        Grid.Row="1"  
-       VerticalOptions="FillAndExpand">  
-           <CollectionView.ItemsLayout>  
-               <LinearItemsLayout Orientation="Vertical"/>  
-           </CollectionView.ItemsLayout>  
-       </CollectionView>  
+       VerticalOptions="FillAndExpand">
+            <CollectionView.ItemsLayout>
+                <LinearItemsLayout Orientation="Vertical"/>
+            </CollectionView.ItemsLayout>
+        </CollectionView>
 
-       <Entry  
-        x:Name="tx_userPrompt"  
-        Placeholder="Ask to the model"  
-        Margin="10"  
-        Grid.Row="2"/>  
+        <Grid Grid.Row="2" ColumnDefinitions="*,Auto" Margin="0,15,0,5">
+            <Entry  
+            x:Name="tx_userPrompt"  
+            Placeholder="Ask to the model"  
+            Margin="0,0,10,0"
+            Grid.Column="0"/>
+            
+            <Button   
+            x:Name="btn_ask"  
+            Text="Ask"  
+            Clicked="OnAskClicked"  
+            IsEnabled="False"  
+            Grid.Column="1"/>
+            
+        </Grid>
 
-       <Button   
-        x:Name="btn_ask"  
-        Text="Ask"  
-        Clicked="OnAskClicked"  
-        IsEnabled="False"  
-        Margin="10,0,10,10"  
-        Grid.Row="3"/>  
-   </Grid>  
+    </Grid>
 
 </ContentPage>
\ No newline at end of file
diff --git a/Llama.Mobile/MainPage.xaml.cs b/Llama.Mobile/MainPage.xaml.cs
index f0e49a49d..81c862dd1 100644
--- a/Llama.Mobile/MainPage.xaml.cs
+++ b/Llama.Mobile/MainPage.xaml.cs
@@ -103,12 +103,12 @@ private async void OnAskClicked(object sender, EventArgs e)
     {
         btn_ask.IsEnabled = false;
         Messages.Add(new Message { Type = messageType.User, Text = tx_userPrompt.Text, IsPreparing = false });
+        string userPrompt = tx_userPrompt.Text;
         tx_userPrompt.Text="";
         Message response = new Message { Type = messageType.other, Text = "", IsPreparing = true };
         Messages.Add(response);
         chat.ScrollTo(Messages.Last(), position: ScrollToPosition.End, animate: false);
-
-        await foreach (string text in Session.ChatAsync(new ChatHistory.Message(AuthorRole.User, tx_userPrompt.Text), InferenceParams))
+        await foreach (string text in Session.ChatAsync(new ChatHistory.Message(AuthorRole.User, userPrompt), InferenceParams))
         {
             response.IsPreparing = false;
             response.AppendText(text); 

From 856111be9ba27c0fe08daa9e47987e74caf4e5a1 Mon Sep 17 00:00:00 2001
From: Luca Maccarini <lucamaccarini22@gmail.com>
Date: Thu, 3 Jul 2025 14:13:13 +0200
Subject: [PATCH 4/4] Fix misspellings

---
 Llama.Mobile/MainPage.xaml    | 4 ++--
 Llama.Mobile/MainPage.xaml.cs | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/Llama.Mobile/MainPage.xaml b/Llama.Mobile/MainPage.xaml
index 9c8a6a9f4..c640229d0 100644
--- a/Llama.Mobile/MainPage.xaml
+++ b/Llama.Mobile/MainPage.xaml
@@ -3,7 +3,7 @@
 <ContentPage xmlns="http://schemas.microsoft.com/dotnet/2021/maui"  
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"  
             x:Class="Llama.Mobile.MainPage"  
-            Title="Bob, the AI assisant"  
+            Title="Bob, the AI assistant"  
             xmlns:src="clr-namespace:Llama.Mobile.Src"  
             >
 
@@ -63,7 +63,7 @@
     </ContentPage.Resources>
 
     <Grid RowDefinitions="Auto,*,Auto" Margin="10,0,10,0">
-        <HorizontalStackLayout Grid.Row="0" x:Name="pn_loading">
+        <HorizontalStackLayout Grid.Row="0" x:Name="pnl_loading">
             <Label  
            Text="Loading the model"  
            VerticalOptions="Center"  
diff --git a/Llama.Mobile/MainPage.xaml.cs b/Llama.Mobile/MainPage.xaml.cs
index 81c862dd1..6046e0959 100644
--- a/Llama.Mobile/MainPage.xaml.cs
+++ b/Llama.Mobile/MainPage.xaml.cs
@@ -91,7 +91,7 @@ protected override async void OnAppearing()
             new string[] { "\n\nUser:", "\nUser:", "User:", "Assistant: " },
             redundancyLength: 8));
 
-        pn_loading.IsVisible = false;
+        pnl_loading.IsVisible = false;
         btn_ask.IsEnabled = true;
 
         await Task.Delay(100); //on the emulator without this little delay the popup isn't shown