Runtime translation decisions. Not final.

FunctionZero.Maui.Controls/FunctionZero.Maui.Controls.csproj

@@ -29,7 +29,7 @@
 		<PackageLicenseFile>License.md</PackageLicenseFile>
 		<IncludeSymbols>True</IncludeSymbols>
 		<SymbolPackageFormat>snupkg</SymbolPackageFormat>
-		<Version>8.0.0.2-pre6</Version>
+		<Version>8.0.0.2-pre8</Version>
 		<PackageIcon>F0 gravatar.png</PackageIcon>
 	</PropertyGroup>
 

FunctionZero.Maui.Controls/Services/BaseLanguageService.cs → FunctionZero.Maui.Controls/Services/Localisation/BaseLanguageService.cs

@@ -1,4 +1,5 @@
-using FunctionZero.Maui.MarkupExtensions;
+using FunctionZero.ExpressionParserZero.BackingStore;
+using FunctionZero.Maui.MarkupExtensions;
 using System;
 using System.Collections.Generic;
 using System.ComponentModel;
@@ -7,7 +8,7 @@
 using System.Text;
 using System.Threading.Tasks;
 
-namespace FunctionZero.Maui.Services
+namespace FunctionZero.Maui.Services.Localisation
 {
     /// <summary>
     /// Goal. To be decoupled enough to allow downloading and selection of new or updated language packs on the fly.
@@ -68,10 +69,18 @@ public void SetLanguage(string id)
 
         public string[] CurrentLookup => _resourceHost[_resourceKey] as string[];
 
-        public string GetText(TEnum textId)
+        public string GetText(TEnum textId, IBackingStore host)
         {
-            var retval = _languages[CurrentLanguageId].GetLookup()[(int)(object)textId];
-            return retval;
+            var lookup = _languages[CurrentLanguageId].GetLookup()[(int)(object)textId];
+
+            foreach (var item in lookup)
+            {
+                var result = item.Item1.Evaluate(host).Pop();
+                if (result.Type == ExpressionParserZero.Operands.OperandType.Bool)
+                    if ((bool)result.GetValue() == true)
+                        return item.Item2;
+            }
+            return $"textId {textId} not found.";
         }
     }
 }

FunctionZero.Maui.Controls/Services/Localisation/ExpressionString.cs

@@ -0,0 +1,35 @@
+using FunctionZero.ExpressionParserZero.BackingStore;
+using FunctionZero.ExpressionParserZero.Evaluator;
+
+namespace FunctionZero.Maui.Services.Localisation
+{
+    public class ExpressionString
+    {
+        private ExpressionTree _expression;
+        private readonly string _resultString;
+
+        public ExpressionString(ExpressionTree expression, string resultString)
+        {
+            _expression = expression;
+            _resultString = resultString;
+        }
+
+        public bool GetString(object backingStore, ref string result)
+        {
+            result = _resultString;
+
+            try
+            {
+                if (backingStore is IBackingStore pocoBackingStore)
+                    return (bool)_expression.Evaluate(pocoBackingStore).Pop().GetValue();
+                else
+                    return (bool)_expression.Evaluate(new PocoBackingStore(backingStore)).Pop().GetValue();
+            }
+            catch(Exception ex)
+            {
+                result = ex.Message;
+                return false;
+            }
+        }
+    }
+}

FunctionZero.Maui.Controls/Services/LanguageChangedEventArgs.cs → FunctionZero.Maui.Controls/Services/Localisation/LanguageChangedEventArgs.cs

@@ -1,4 +1,4 @@
-namespace FunctionZero.Maui.Services
+namespace FunctionZero.Maui.Services.Localisation
 {
     public class LanguageChangedEventArgs : EventArgs
     {

FunctionZero.Maui.Controls/Services/Localisation/LanguageProvider.cs

@@ -0,0 +1,42 @@
+using FunctionZero.ExpressionParserZero.Binding;
+using FunctionZero.ExpressionParserZero.Evaluator;
+
+namespace FunctionZero.Maui.Services.Localisation
+{
+    public class LanguageProvider
+    {
+        private readonly ExpressionTree _trueExpression;
+
+        public LanguageProvider(Func<List<List<(ExpressionTree, string)>>> getLookup, string languageName)
+        {
+            GetLookup = getLookup;
+            LanguageName = languageName;
+        }
+        //item.Add((parser.Parse("true"), "There are loads of bananas!"));
+        public LanguageProvider(Func<IEnumerable<string>> getLookup, string languageName)
+        {
+            var parser = ExpressionParserFactory.GetExpressionParser();
+            _trueExpression = parser.Parse("true");
+
+            GetLookup = GetLookupFromStringList(getLookup);
+            LanguageName = languageName;
+        }
+
+        private Func<List<List<(ExpressionTree, string)>>> GetLookupFromStringList(Func<IEnumerable<string>> getLookup)
+        {
+            List<List<(ExpressionTree, string)>> lookup = new List<List<(ExpressionTree, string)>>();
+            foreach (var theString in getLookup())
+            {
+                var item = new List<(ExpressionTree, string)>();
+                item.Add((_trueExpression, theString));
+                lookup.Add(item);
+            }
+            return () => lookup;
+        }
+
+
+        //public Func<string[]> GetLookup { get; }
+        public Func<List<List<(ExpressionTree, string)>>> GetLookup { get; }
+        public string LanguageName { get; }
+    }
+}

SampleApp/MauiProgram.cs

@@ -1,9 +1,11 @@
 using FunctionZero.ExpressionParserZero.Binding;
 using FunctionZero.ExpressionParserZero.Evaluator;
+using FunctionZero.ExpressionParserZero.Operands;
 using FunctionZero.ExpressionParserZero.Parser;
 using FunctionZero.Maui.Controls;
 using FunctionZero.Maui.MvvmZero;
 using FunctionZero.Maui.Services;
+using FunctionZero.Maui.Services.Localisation;
 using SampleApp.Mvvm.Pages;
 using SampleApp.Mvvm.Pages.Expander;
 using SampleApp.Mvvm.Pages.List;
@@ -49,7 +51,7 @@ public static MauiApp CreateMauiApp()
                         .MapVmToView<MultiViewModalPageVm, MultiViewModalPage>()
                         .MapVmToView<TranslationHomePageVm, TranslationHomePage>()
 
-                        
+
                         ;
                     }
                 )
@@ -121,21 +123,101 @@ private static LangService GetConfiguredLanguageService(IServiceProvider provide
         }
 
         // Example
-        private static string[] GetEnglish() => new string[] { "Hello", "World", "Welcome to the Moasure Playground!" };
-        private static string[] GetGerman() => new string[] { "Hallo", "Welt", "Willkommen auf dem Moasure Spielplatz!" };
+        //private static string[] GetEnglish() => new string[] { "Hello", "World", "Welcome to the Moasure Playground!" };
+        private static string[] GetGerman() => new string[] { "Bananas", "Hallo", "Welt", "Willkommen auf dem Moasure Spielplatz!" };
 
-        //private static List<(ExpressionTree, string)> GetEnglish2()
-        //{
-        //    var retval = new List<(ExpressionTree, string)>();
+        private static List<List<(ExpressionTree, string)>> GetEnglish()
+        {
+            var parser = ExpressionParserFactory.GetExpressionParser();
+            var trueExpression = parser.Parse("true");
+
+            var retval = new List<List<(ExpressionTree, string)>>();
+
+            {
+                var item = new List<(ExpressionTree, string)>();
+
+                item.Add((parser.Parse("NumBananas == 0"), "There are no bananas!"));
+                item.Add((parser.Parse("NumBananas == 1"), "There is one banana!"));
+                item.Add((parser.Parse("NumBananas == 2"), "There are two bananas!"));
+                item.Add((parser.Parse("NumBananas < 10"), "There are {NumBananas} bananas!"));       // TODO: {NumBananas}
+                item.Add((parser.Parse("true"), "There are loads of bananas!"));
+
+                //HashSet<string> dependsOn = new HashSet<string>();
+
+                //foreach(var tuple in item)
+                //    foreach(var token in tuple.Item1.RpnTokens)
+                //        if(token is Operand op)
+                //            if(op.Type == OperandType.Variable)
+                //                dependsOn.Add((string)op.GetValue());
+
+                retval.Add(item);
+            }
+            {
+                var item = new List<(ExpressionTree, string)>();
+
+                item.Add((trueExpression, "Hello!"));
+
+                retval.Add(item);
+            }
+            {
+                var item = new List<(ExpressionTree, string)>();
+
+                item.Add((trueExpression, "World"));
+
+                retval.Add(item);
+            }
+            {
+                var item = new List<(ExpressionTree, string)>();
+
+                item.Add((trueExpression, "This is a demonstration of FunctionZero Translation Service"));
 
+                retval.Add(item);
+            }
+
+
+            return retval;
+        }
+
+        //private static List<List<(ExpressionTree, string)>> GetGerman()
+        //{
         //    var parser = ExpressionParserFactory.GetExpressionParser();
+        //    var trueExpression = parser.Parse("true");
+
+        //    var retval = new List<List<(ExpressionTree, string)>>();
+
+        //    {
+        //        var item = new List<(ExpressionTree, string)>();
+
+        //        item.Add((parser.Parse("NumBananas == 0"), "Es gibt keine Bananen!"));
+        //        item.Add((parser.Parse("NumBananas == 1"), "Es gibt eine Banane!"));
+        //        item.Add((parser.Parse("NumBananas == 2"), "Es gibt zwei Bananen!"));
+        //        item.Add((parser.Parse("NumBananas < 10"), "Es gibt {NumBananas} Bananen!"));       // TODO: {NumBananas}
+        //        item.Add((parser.Parse("true"), "Es gibt jede Menge Bananen!"));
+
+        //        retval.Add(item);
+        //    }
+        //    {
+        //        var item = new List<(ExpressionTree, string)>();
+
+        //        item.Add((trueExpression, "Hallo!"));
+
+        //        retval.Add(item);
+        //    }
+        //    {
+        //        var item = new List<(ExpressionTree, string)>();
+
+        //        item.Add((trueExpression, "Welt"));
+
+        //        retval.Add(item);
+        //    }
+        //    {
+        //        var item = new List<(ExpressionTree, string)>();
+
+        //        item.Add((trueExpression, "Dies ist eine Demonstration des FunctionZero Translation Service"));
 
-        //    retval.Add((parser.Parse("NumBananas == 0"), "There are no bananas!"));
+        //        retval.Add(item);
+        //    }
 
-        //    retval.Add((parser.Parse("NumBananas == 1"), "There is one banana!"));
-        //    retval.Add((parser.Parse("NumBananas == 2"), "There are two bananas!"));
-        //    retval.Add((parser.Parse("NumBananas < 10"), "There are {NumBananas} bananas!"));       // TODO: {NumBananas}
-        //    retval.Add((parser.Parse("true"), "There are loads of bananas!"));
 
         //    return retval;
         //}

SampleApp/Mvvm/PageViewModels/Translations/TranslationHomePageVm.cs

@@ -1,4 +1,5 @@
 using FunctionZero.CommandZero;
+using FunctionZero.ExpressionParserZero.BackingStore;
 using FunctionZero.Maui.MvvmZero;
 using FunctionZero.Maui.Services;
 using SampleApp.Mvvm.ViewModels;
@@ -23,6 +24,8 @@ public TranslationHomePageVm(LangService langService)
         {
             _langService = langService;
 
+            var thisAsPocoBackingStore = new PocoBackingStore(this);
+
             SetLanguageCommand = new CommandBuilder()
                 .AddGuard(this)
                 .SetExecute(SetLanguageCommandExecute)
@@ -31,9 +34,18 @@ public TranslationHomePageVm(LangService langService)
             DoTheThingCommand = new CommandBuilder()
                 .AddGuard(this)
                 .SetExecute(DoTheThingCommandExecute)
-                .SetName(() => langService.GetText(LangStrings.E_World))
+                .SetName(() => langService.GetText(LangStrings.E_Bananas, thisAsPocoBackingStore))
                 .AddObservedProperty(langService, nameof(LangService.CurrentLanguageId))
                 .Build();
+
+            NumBananas = 1;
+        }
+
+        private int _numBananas;
+        public int NumBananas
+        {
+            get => _numBananas;
+            set => SetProperty(ref _numBananas, value);
         }
 
         private void DoTheThingCommandExecute()

SampleApp/Translations/LangService.cs

@@ -1,5 +1,5 @@
 using FunctionZero.Maui.MarkupExtensions;
-using FunctionZero.Maui.Services;
+using FunctionZero.Maui.Services.Localisation;
 using System;
 using System.Collections.Generic;
 using System.Linq;

SampleApp/Translations/LangStrings.cs

@@ -12,8 +12,9 @@ namespace SampleApp.Translations
     /// </summary>
     public enum LangStrings
     {
+        E_Bananas,
         E_Hello,
         E_World,
-        E_Welcome
+        E_Welcome,
     }
 }