﻿using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Microsoft.VisualStudio.TestTools.UnitTesting;
using OfficeOpenXml.FormulaParsing;
using OfficeOpenXml.FormulaParsing.Excel.Functions;
using OfficeOpenXml.FormulaParsing.Excel.Functions.Information;
using OfficeOpenXml.FormulaParsing.Excel.Functions.Logical;
using OfficeOpenXml.FormulaParsing.Excel.Functions.Math;
using OfficeOpenXml.FormulaParsing.Excel.Functions.RefAndLookup;
using OfficeOpenXml.FormulaParsing.ExpressionGraph;
using OfficeOpenXml.FormulaParsing.ExpressionGraph.FunctionCompilers;

namespace EPPlusTest.FormulaParsing.ExpressionGraph.FunctionCompilers
{
    [TestClass]
    public class FunctionCompilerFactoryTests
    {
        #region Create Tests
        [TestMethod]
        public void CreateHandlesStandardFunctionCompiler()
        {
            var functionRepository = FunctionRepository.Create();
            var functionCompilerFactory = new FunctionCompilerFactory(functionRepository);
            var function = new Sum();
            var functionCompiler = functionCompilerFactory.Create(function);
            Assert.IsInstanceOfType(functionCompiler, typeof(DefaultCompiler));
        }

        [TestMethod]
        public void CreateHandlesSpecialIfCompiler()
        {
            var functionRepository = FunctionRepository.Create();
            var functionCompilerFactory = new FunctionCompilerFactory(functionRepository);
            var function = new If();
            var functionCompiler = functionCompilerFactory.Create(function);
            Assert.IsInstanceOfType(functionCompiler, typeof(IfFunctionCompiler));
        }

        [TestMethod]
        public void CreateHandlesSpecialIfErrorCompiler()
        {
            var functionRepository = FunctionRepository.Create();
            var functionCompilerFactory = new FunctionCompilerFactory(functionRepository);
            var function = new IfError();
            var functionCompiler = functionCompilerFactory.Create(function);
            Assert.IsInstanceOfType(functionCompiler, typeof(IfErrorFunctionCompiler));
        }

        [TestMethod]
        public void CreateHandlesSpecialIfNaCompiler()
        {
            var functionRepository = FunctionRepository.Create();
            var functionCompilerFactory = new FunctionCompilerFactory(functionRepository);
            var function = new IfNa();
            var functionCompiler = functionCompilerFactory.Create(function);
            Assert.IsInstanceOfType(functionCompiler, typeof(IfNaFunctionCompiler));
        }

        [TestMethod]
        public void CreateHandlesLookupFunctionCompiler()
        {
            var functionRepository = FunctionRepository.Create();
            var functionCompilerFactory = new FunctionCompilerFactory(functionRepository);
            var function = new Column();
            var functionCompiler = functionCompilerFactory.Create(function);
            Assert.IsInstanceOfType(functionCompiler, typeof(LookupFunctionCompiler));
        }

        [TestMethod]
        public void CreateHandlesErrorFunctionCompiler()
        {
            var functionRepository = FunctionRepository.Create();
            var functionCompilerFactory = new FunctionCompilerFactory(functionRepository);
            var function = new IsError();
            var functionCompiler = functionCompilerFactory.Create(function);
            Assert.IsInstanceOfType(functionCompiler, typeof(ErrorHandlingFunctionCompiler));
        }

        [TestMethod]
        public void CreateHandlesCustomFunctionCompiler()
        {
            var functionRepository = FunctionRepository.Create();
            functionRepository.LoadModule(new TestFunctionModule());
            var functionCompilerFactory = new FunctionCompilerFactory(functionRepository);
            var function = new MyFunction();
            var functionCompiler = functionCompilerFactory.Create(function);
            Assert.IsInstanceOfType(functionCompiler, typeof(MyFunctionCompiler));
        }
        #endregion

        #region Nested Classes
        public class TestFunctionModule : FunctionsModule
        {
            public TestFunctionModule()
            {
                var myFunction = new MyFunction();
                var customCompiler = new MyFunctionCompiler(myFunction);
                base.Functions.Add(MyFunction.Name, myFunction);
                base.CustomCompilers.Add(typeof(MyFunction), customCompiler);
            }
        }

        public class MyFunction : ExcelFunction
        {
            public const string Name = "MyFunction";
            public override CompileResult Execute(IEnumerable<FunctionArgument> arguments, ParsingContext context)
            {
                throw new NotImplementedException();
            }
        }

        public class MyFunctionCompiler : FunctionCompiler
        {
            public MyFunctionCompiler(MyFunction function) : base(function) { }
            public override CompileResult Compile(IEnumerable<Expression> children, ParsingContext context)
            {
                throw new NotImplementedException();
            }
        }
        #endregion
    }
}