using MathEngine.Parser.Tokeniser;
using MathEngine.Parser.Parser;
namespace EngineTests
{
    /// <summary>
    /// Class for testing the ExpressionTree Class
    /// </summary>
    [TestClass]
    public class ExpressionTreeTests
    {

        /// <summary>
        /// Test to see if a simple expression is constructed correctly
        /// </summary>
        [TestMethod]
        public void TestExpressionTreeSimpleExpression()
        {
            string testExp = "3+4";
            ExpressionTree returnedTree = new(testExp);
            Assert.IsTrue(returnedTree.ToString() == "7");
        }

        /// <summary>
        /// Test to see if a simple expression is evaluated correctly
        /// </summary>
        [TestMethod]
        public void TestExpressionTreeSimpleExpressionEvaluation()
        {
            string testExp = "3+4*7";
            ExpressionTree returnedTree = new(testExp);
            Assert.IsTrue(returnedTree.ToString() == "31");
        }

        /// <summary>
        /// Test to see if a simple expression using all base operators (+,-,*,/) is evaluated correctly
        /// </summary>
        [TestMethod]
        public void TestExpressionTreeSimpleExpressionAllBaseOperatorsEvaluation()
        {
            string testExp = "3+4*7-8/7";
            decimal testValue = decimal.Divide(209 , 7);
            ExpressionTree returnedTree = new(testExp);
            Assert.IsTrue(returnedTree.ToString() == testValue.ToString());
        }

        [TestMethod]
        public void TestExpressionTreeGetHashCodeReturnsHashCode()
        {
            string testExp = "1+1";
            ExpressionTree returnedTree1 = new(testExp);
            int hash = returnedTree1.GetHashCode();
            Assert.IsInstanceOfType(hash, typeof(int));
        }
    }
}