Sicherung

Kalk/Kalk.Core/Modules/Currencies/KalkCurrency.cs

@@ -0,0 +1,80 @@
+using System;
+using System.Globalization;
+using System.Net.Http;
+using System.Text;
+using System.Threading.Tasks;
+using Kalk.Core.Modules;
+using Scriban;
+using Scriban.Parsing;
+using Scriban.Runtime;
+using Scriban.Syntax;
+
+namespace Kalk.Core
+{
+    public class KalkCurrency : KalkUnit
+    {
+        private readonly CurrencyModule _currencyModule;
+        private const int CurrencyColumnAlign = 27;
+
+        public KalkCurrency(CurrencyModule currencyModule, string name) : base(name)
+        {
+            _currencyModule = currencyModule;
+            Plural = name;
+        }
+
+        public override string TypeName => "currency";
+
+        public override object GetValue() => 1.0m;
+        
+        public override object Invoke(TemplateContext context, ScriptNode callerContext, ScriptArray arguments, ScriptBlockStatement blockStatement)
+        {
+            if (!(callerContext.Parent is ScriptExpressionStatement))
+            {
+                return this;
+            }
+
+            var engine = (KalkEngine)context;
+
+            string currencyCmd;
+            string currencyDesc;
+            if (Value == null)
+            {
+                currencyCmd = $"currency({Name});";
+                currencyDesc = $"Base currency";
+            }
+            else
+            {
+                var value = (KalkBinaryExpression) Value;
+
+                var valueToBase = 1.0m / (decimal) value.Value;
+                var format = "#0.0###";
+                if (valueToBase < 0.0001m)
+                {
+                    format = null;
+                }
+
+                var formattedNumber = valueToBase.ToString(format, CultureInfo.InvariantCulture);
+
+                currencyCmd = $"currency({Name}, {formattedNumber});";
+                currencyDesc = $"{formattedNumber,-8} {Name} => 1 {_currencyModule.GetSafeBaseCurrencyFromConfig().Name}";
+            }
+
+            engine.WriteHighlightLine($"{currencyCmd, -CurrencyColumnAlign} # {currencyDesc}");
+
+            return null;
+        }
+
+        public static void CheckValid(SourceSpan span, string name)
+        {
+            if (name == null) throw new ArgumentNullException(nameof(name));
+            if (name.Length != 3) throw new ScriptRuntimeException(span, $"Base currency `{name}` must 3 characters long instead of {name.Length}.");
+            foreach (var c in name)
+            {
+                if (!(c >= 'A' && c <= 'Z'))
+                {
+                    throw new ScriptRuntimeException(span, $"The character `{c}` is invalid for the base currency `{name}`. Only A-Z are allowed");
+                }
+            }
+        }
+    }
+}