using MathEngine.Parser.Tokeniser;
using Newtonsoft.Json.Linq;

namespace EngineTests.Parser_Tests.Tokeniser
{
    /// <summary>
    /// Class for testing the Token
    /// </summary>
    [TestClass]
    public class TokenTests
    {
        /// <summary>
        /// Test that Token constructor returns valid token
        /// </summary>
        [TestMethod]
        public void TestTokenConstructorReturnsToken()
        {
            string testTokenValue = "123";
            Token.Type testTokenType = Token.Type.Numeric;
            Token.NumericType testNumericType = Token.NumericType.Integer;
            uint testArityValue = 0;

            Token token = new(testTokenValue, testTokenType, testNumericType, testArityValue);
            Assert.IsNotNull(token);
            Assert.AreEqual(token.TokenValue, testTokenValue);
            Assert.AreEqual(token.Token_Type, testTokenType);
            Assert.AreEqual(token.NumericalType, testNumericType);
            Assert.AreEqual(token.FunctionArity, testArityValue);
        }

#if DEBUG
        /// <summary>
        /// Test ToString returns expected string format
        /// </summary>
        [TestMethod]
        public void TestToStringReturnsExpetedStringFormat()
        {
            string testTokenValue = "123";
            Token.Type testTokenType = Token.Type.Numeric;
            Token.NumericType testNumericType = Token.NumericType.Integer;
            uint testArityValue = 0;

            Token token1 = new(testTokenValue, testTokenType, testNumericType, testArityValue);

            string token_string = token1.ToString();
            Assert.AreEqual(token_string, "123,Numeric,Integer,0");
        }
#endif
        /// <summary>
        /// Test for == operator comparing two equal Tokens returns true
        /// </summary>
        [TestMethod]
        public void TestTokenEqualOperatorReturnsTrueOnEqualTokens()
        {
            string testTokenValue = "123";
            Token.Type testTokenType = Token.Type.Numeric;
            Token.NumericType testNumericType = Token.NumericType.Integer;
            uint testArityValue = 0;

            string testTokenValue2 = "123";
            Token.Type testTokenType2 = Token.Type.Numeric;
            Token.NumericType testNumericType2 = Token.NumericType.Integer;
            uint testArityValue2 = 0;

            Token token1 = new(testTokenValue, testTokenType, testNumericType, testArityValue);
            Token token2 = new(testTokenValue2, testTokenType2, testNumericType2, testArityValue2);
            Assert.AreEqual(token1 == token2, true);
        }

        /// <summary>
        /// Test for == operator comparing unequal Tokens returns false
        /// </summary>
        [TestMethod]
        public void TestTokenEqualOperatorReturnsFalseOnUnequalTokens()
        {
            string testTokenValue1 = "123";
            Token.Type testTokenType1 = Token.Type.Numeric;
            Token.NumericType testNumericType1 = Token.NumericType.Integer;
            uint testArityValue1 = 0;

            string testTokenValue2 = "125";
            Token.Type testTokenType2 = Token.Type.Numeric;
            Token.NumericType testNumericType2 = Token.NumericType.Integer;
            uint testArityValue2 = 0;

            string testTokenValue3 = "123";
            Token.Type testTokenType3 = Token.Type.Operator;
            Token.NumericType testNumericType3 = Token.NumericType.Integer;
            uint testArityValue3 = 0;

            string testTokenValue4 = "123";
            Token.Type testTokenType4 = Token.Type.Numeric;
            Token.NumericType testNumericType4 = Token.NumericType.Decimal;
            uint testArityValue4 = 0;

            string testTokenValue5 = "123";
            Token.Type testTokenType5 = Token.Type.Numeric;
            Token.NumericType testNumericType5 = Token.NumericType.Integer;
            uint testArityValue5 = 1;

            Token token1 = new(testTokenValue1, testTokenType1, testNumericType1, testArityValue1);
            Token token2 = new(testTokenValue2, testTokenType2, testNumericType2, testArityValue2);
            Token token3 = new(testTokenValue3, testTokenType3, testNumericType3, testArityValue3);
            Token token4 = new(testTokenValue4, testTokenType4, testNumericType4, testArityValue4);
            Token token5 = new(testTokenValue5, testTokenType5, testNumericType5, testArityValue5);

            Assert.AreEqual(token1 == token2, false);
            Assert.AreEqual(token1 == token3, false);
            Assert.AreEqual(token1 == token4, false);
            Assert.AreEqual(token1 == token5, false);
        }

        /// <summary>
        /// Test for != operator comparing two equal Tokens returns true
        /// </summary>
        [TestMethod]
        public void TestTokenUnEqualOperatorReturnsFalseOnEqualTokens()
        {
            string testTokenValue = "123";
            Token.Type testTokenType = Token.Type.Numeric;
            Token.NumericType testNumericType = Token.NumericType.Integer;
            uint testArityValue = 0;

            Token token1 = new(testTokenValue, testTokenType, testNumericType, testArityValue);
            Token token2 = new(testTokenValue, testTokenType, testNumericType, testArityValue);
            Assert.AreEqual(token1 != token2, false);
        }

        /// <summary>
        /// Test for != operator comparing unequal Tokens returns True
        /// </summary>
        [TestMethod]
        public void TestTokenUnEqualOperatorReturnsTrueOnUnequalTokens()
        {
            string testTokenValue1 = "123";
            Token.Type testTokenType1 = Token.Type.Numeric;
            Token.NumericType testNumericType1 = Token.NumericType.Integer;
            uint testArityValue1 = 0;

            string testTokenValue2 = "125";
            Token.Type testTokenType2 = Token.Type.Numeric;
            Token.NumericType testNumericType2 = Token.NumericType.Integer;
            uint testArityValue2 = 0;

            string testTokenValue3 = "123";
            Token.Type testTokenType3 = Token.Type.Operator;
            Token.NumericType testNumericType3 = Token.NumericType.Integer;
            uint testArityValue3 = 0;

            string testTokenValue4 = "123";
            Token.Type testTokenType4 = Token.Type.Numeric;
            Token.NumericType testNumericType4 = Token.NumericType.Decimal;
            uint testArityValue4 = 0;

            string testTokenValue5 = "123";
            Token.Type testTokenType5 = Token.Type.Numeric;
            Token.NumericType testNumericType5 = Token.NumericType.Integer;
            uint testArityValue5 = 1;

            Token token1 = new(testTokenValue1, testTokenType1, testNumericType1, testArityValue1);
            Token token2 = new(testTokenValue2, testTokenType2, testNumericType2, testArityValue2);
            Token token3 = new(testTokenValue3, testTokenType3, testNumericType3, testArityValue3);
            Token token4 = new(testTokenValue4, testTokenType4, testNumericType4, testArityValue4);
            Token token5 = new(testTokenValue5, testTokenType5, testNumericType5, testArityValue5);

            Assert.AreEqual(token1 != token2, true);
            Assert.AreEqual(token1 != token3, true);
            Assert.AreEqual(token1 != token4, true);
            Assert.AreEqual(token1 != token5, true);
        }

        /// <summary>
        /// Test Equals method returns True when Tokens are equal
        /// </summary>
        [TestMethod]
        public void TestTokenEqualsMethodWithTokenObjectsReturnsTrueWhenEqual()
        {
            string testTokenValue = "123";
            Token.Type testTokenType = Token.Type.Numeric;
            Token.NumericType testNumericType = Token.NumericType.Integer;
            uint testArityValue = 0;

            string testTokenValue2 = "123";
            Token.Type testTokenType2 = Token.Type.Numeric;
            Token.NumericType testNumericType2 = Token.NumericType.Integer;
            uint testArityValue2 = 0;

            Token token1 = new(testTokenValue, testTokenType, testNumericType, testArityValue);
            Token token2 = new(testTokenValue2, testTokenType2, testNumericType2, testArityValue2);
            Assert.AreEqual(token1.Equals(token2), true);
        }

        /// <summary>
        /// Test Equals method returns False when Tokens are unequal
        /// </summary>
        [TestMethod]
        public void TestTokenEqualsMethodWithTokenObjectsReturnsFalseWhenUnequal()
        { 
            string testTokenValue1 = "123";
            Token.Type testTokenType1 = Token.Type.Numeric;
            Token.NumericType testNumericType1 = Token.NumericType.Integer;
            uint testArityValue1 = 0;

            string testTokenValue2 = "125";
            Token.Type testTokenType2 = Token.Type.Numeric;
            Token.NumericType testNumericType2 = Token.NumericType.Integer;
            uint testArityValue2 = 0;
            
            string testTokenValue3 = "123";
            Token.Type testTokenType3 = Token.Type.Operator;
            Token.NumericType testNumericType3 = Token.NumericType.Integer;
            uint testArityValue3 = 0;
            
            string testTokenValue4 = "123";
            Token.Type testTokenType4 = Token.Type.Numeric;
            Token.NumericType testNumericType4 = Token.NumericType.Decimal;
            uint testArityValue4 = 0;
            
            string testTokenValue5 = "123";
            Token.Type testTokenType5 = Token.Type.Numeric;
            Token.NumericType testNumericType5 = Token.NumericType.Integer;
            uint testArityValue5 = 1;
            
            Token token1 = new(testTokenValue1, testTokenType1, testNumericType1, testArityValue1);
            Token token2 = new(testTokenValue2, testTokenType2, testNumericType2, testArityValue2);
            Token token3 = new(testTokenValue3, testTokenType3, testNumericType3, testArityValue3);
            Token token4 = new(testTokenValue4, testTokenType4, testNumericType4, testArityValue4);
            Token token5 = new(testTokenValue5, testTokenType5, testNumericType5, testArityValue5);
            
            Assert.AreEqual(token1.Equals(token2), false);
            Assert.AreEqual(token1.Equals(token3), false);
            Assert.AreEqual(token1.Equals(token4), false);
            Assert.AreEqual(token1.Equals(token5), false);
        }

        /// <summary>
        /// Test Equals method checks for Token equality when object is a token
        /// </summary>
        [TestMethod]
        public void TestTokenEqualsMethodWithObjectsThatIsATokenComparesForTokenEquality()
        {
            string testTokenValue = "123";
            Token.Type testTokenType = Token.Type.Numeric;
            Token.NumericType testNumericType = Token.NumericType.Integer;
            uint testArityValue = 0;

            string testTokenValue2 = "123";
            Token.Type testTokenType2 = Token.Type.Numeric;
            Token.NumericType testNumericType2 = Token.NumericType.Integer;
            uint testArityValue2 = 0;

            Token token1 = new(testTokenValue, testTokenType, testNumericType, testArityValue);
            Token token2 = new(testTokenValue2, testTokenType2, testNumericType2, testArityValue2);
            object token_obj = token2;
            Assert.AreEqual(token1.Equals(token_obj), true);
        }

        /// <summary>
        /// Test Equals method checks for returns false when object is not a token
        /// </summary>
        [TestMethod]
        public void TestTokenEqualsMethodWithObjectsThatIsNotATokenReturnsFalse()
        {
            string testTokenValue = "123";
            Token.Type testTokenType = Token.Type.Numeric;
            Token.NumericType testNumericType = Token.NumericType.Integer;
            uint testArityValue = 0;

            int non_token = 5;

            Token token1 = new(testTokenValue, testTokenType, testNumericType, testArityValue);
            Assert.AreEqual(token1.Equals(non_token), false);
        }

        /// <summary>
        /// Test GetHashCode on two tokens with same values is the same
        /// </summary>
        [TestMethod]
        public void TestTokenGetHashCodeOnTwoTokensWhichHaveSameValuesAreEqual()
        {
            string testTokenValue = "123";
            Token.Type testTokenType = Token.Type.Numeric;
            Token.NumericType testNumericType = Token.NumericType.Integer;
            uint testArityValue = 0;

            string testTokenValue2 = "123";
            Token.Type testTokenType2 = Token.Type.Numeric;
            Token.NumericType testNumericType2 = Token.NumericType.Integer;
            uint testArityValue2 = 0;

            Token token1 = new(testTokenValue, testTokenType, testNumericType, testArityValue);
            Token token2 = new(testTokenValue2, testTokenType2, testNumericType2, testArityValue2);

            int hash1 = token1.GetHashCode();
            int hash2 = token2.GetHashCode();
            Assert.AreEqual(hash1, hash2);
        }

        /// <summary>
        /// Test GetHashCode on two tokens with different values are different
        /// </summary>
        [TestMethod]
        public void TestTokenGetHashCodeOnTwoTokensWhichHaveDifferentValuesAreUnequal()
        {
            string testTokenValue = "123";
            Token.Type testTokenType = Token.Type.Numeric;
            Token.NumericType testNumericType = Token.NumericType.Integer;
            uint testArityValue = 0;

            string testTokenValue2 = "125";
            Token.Type testTokenType2 = Token.Type.Numeric;
            Token.NumericType testNumericType2 = Token.NumericType.Integer;
            uint testArityValue2 = 0;

            Token token1 = new(testTokenValue, testTokenType, testNumericType, testArityValue);
            Token token2 = new(testTokenValue2, testTokenType2, testNumericType2, testArityValue2);

            int hash1 = token1.GetHashCode();
            int hash2 = token2.GetHashCode();
            Assert.AreNotEqual(hash1, hash2);
        }
    }
}