// Copyright (c) .NET Foundation. All rights reserved.
// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.

using System;
using System.Web.WebPages.TestUtils;
using Microsoft.AspNet.Razor.Text;
#if !DNXCORE50
using Moq;
#endif
using Xunit;

namespace Microsoft.AspNet.Razor.Test.Text
{
    public class TextChangeTest
    {
#if !DNXCORE50
        [Fact]
        public void ConstructorRequiresNonNegativeOldPosition()
        {
            var parameterName = "oldPosition";
            var exception = Assert.Throws<ArgumentOutOfRangeException>(parameterName, () => new TextChange(-1, 0, new Mock<ITextBuffer>().Object, 0, 0, new Mock<ITextBuffer>().Object));
            ExceptionHelpers.ValidateArgumentException(parameterName, "Value must be greater than or equal to 0.", exception);
        }

        [Fact]
        public void ConstructorRequiresNonNegativeNewPosition()
        {
            var parameterName = "newPosition";
            var exception = Assert.Throws<ArgumentOutOfRangeException>(parameterName, () => new TextChange(0, 0, new Mock<ITextBuffer>().Object, -1, 0, new Mock<ITextBuffer>().Object));
            ExceptionHelpers.ValidateArgumentException(parameterName, "Value must be greater than or equal to 0.", exception);
        }

        [Fact]
        public void ConstructorRequiresNonNegativeOldLength()
        {
            var parameterName = "oldLength";
            var exception = Assert.Throws<ArgumentOutOfRangeException>(parameterName, () => new TextChange(0, -1, new Mock<ITextBuffer>().Object, 0, 0, new Mock<ITextBuffer>().Object));
            ExceptionHelpers.ValidateArgumentException(parameterName, "Value must be greater than or equal to 0.", exception);
        }

        [Fact]
        public void ConstructorRequiresNonNegativeNewLength()
        {
            var parameterName = "newLength";
            var exception = Assert.Throws<ArgumentOutOfRangeException>(parameterName, () => new TextChange(0, 0, new Mock<ITextBuffer>().Object, 0, -1, new Mock<ITextBuffer>().Object));
            ExceptionHelpers.ValidateArgumentException(parameterName, "Value must be greater than or equal to 0.", exception);
        }

        [Fact]
        public void ConstructorInitializesProperties()
        {
            // Act
            var oldBuffer = new Mock<ITextBuffer>().Object;
            var newBuffer = new Mock<ITextBuffer>().Object;
            var change = new TextChange(42, 24, oldBuffer, 1337, newBuffer);

            // Assert
            Assert.Equal(42, change.OldPosition);
            Assert.Equal(24, change.OldLength);
            Assert.Equal(1337, change.NewLength);
            Assert.Same(newBuffer, change.NewBuffer);
            Assert.Same(oldBuffer, change.OldBuffer);
        }

        [Fact]
        public void TestIsDelete()
        {
            // Arrange
            var oldBuffer = new Mock<ITextBuffer>().Object;
            var newBuffer = new Mock<ITextBuffer>().Object;
            var change = new TextChange(0, 1, oldBuffer, 0, newBuffer);

            // Assert
            Assert.True(change.IsDelete);
        }

        [Fact]
        public void TestDeleteCreatesTheRightSizeChange()
        {
            // Arrange
            var oldBuffer = new Mock<ITextBuffer>().Object;
            var newBuffer = new Mock<ITextBuffer>().Object;
            var change = new TextChange(0, 1, oldBuffer, 0, newBuffer);

            // Assert
            Assert.Equal(0, change.NewText.Length);
            Assert.Equal(1, change.OldText.Length);
        }

        [Fact]
        public void TestIsInsert()
        {
            // Arrange
            var oldBuffer = new Mock<ITextBuffer>().Object;
            var newBuffer = new Mock<ITextBuffer>().Object;
            var change = new TextChange(0, 0, oldBuffer, 35, newBuffer);

            // Assert
            Assert.True(change.IsInsert);
        }

        [Fact]
        public void TestInsertCreateTheRightSizeChange()
        {
            // Arrange
            var oldBuffer = new Mock<ITextBuffer>().Object;
            var newBuffer = new Mock<ITextBuffer>().Object;
            var change = new TextChange(0, 0, oldBuffer, 1, newBuffer);

            // Assert
            Assert.Equal(1, change.NewText.Length);
            Assert.Equal(0, change.OldText.Length);
        }

        [Fact]
        public void TestIsReplace()
        {
            // Arrange
            var oldBuffer = new Mock<ITextBuffer>().Object;
            var newBuffer = new Mock<ITextBuffer>().Object;
            var change = new TextChange(0, 5, oldBuffer, 10, newBuffer);

            // Assert
            Assert.True(change.IsReplace);
        }

        [Fact]
        public void ReplaceCreatesTheRightSizeChange()
        {
            // Arrange
            var oldBuffer = new Mock<ITextBuffer>().Object;
            var newBuffer = new Mock<ITextBuffer>().Object;
            var change = new TextChange(0, 5, oldBuffer, 10, newBuffer);

            // Assert
            Assert.Equal(10, change.NewText.Length);
            Assert.Equal(5, change.OldText.Length);
        }

        [Fact]
        public void ReplaceCreatesTheRightSizeChange1()
        {
            // Arrange
            var oldBuffer = new Mock<ITextBuffer>().Object;
            var newBuffer = new Mock<ITextBuffer>().Object;
            var change = new TextChange(0, 5, oldBuffer, 1, newBuffer);

            // Assert
            Assert.Equal(1, change.NewText.Length);
            Assert.Equal(5, change.OldText.Length);
        }
#endif

        [Fact]
        public void OldTextReturnsOldSpanFromOldBuffer()
        {
            // Arrange
            var newBuffer = new StringTextBuffer("test");
            var oldBuffer = new StringTextBuffer("text");
            var textChange = new TextChange(2, 1, oldBuffer, 1, newBuffer);

            // Act
            var text = textChange.OldText;

            // Assert
            Assert.Equal("x", text);
        }

        [Fact]
        public void OldTextReturnsOldSpanFromOldBuffer2()
        {
            // Arrange
            var newBuffer = new StringTextBuffer("test");
            var oldBuffer = new StringTextBuffer("text");
            var textChange = new TextChange(2, 2, oldBuffer, 1, newBuffer);

            // Act
            var text = textChange.OldText;

            // Assert
            Assert.Equal("xt", text);
        }

        [Fact]
        public void NewTextWithInsertReturnsChangedTextFromBuffer()
        {
            // Arrange
            var newBuffer = new StringTextBuffer("test");
            var oldBuffer = new StringTextBuffer("");
            var textChange = new TextChange(0, 0, oldBuffer, 3, newBuffer);

            // Act
            var text = textChange.NewText;
            var oldText = textChange.OldText;

            // Assert
            Assert.Equal("tes", text);
            Assert.Equal("", oldText);
        }

        [Fact]
        public void NewTextWithDeleteReturnsEmptyString()
        {
            // Arrange
            var newBuffer = new StringTextBuffer("test");
            var oldBuffer = new StringTextBuffer("");
            var textChange = new TextChange(1, 1, oldBuffer, 0, newBuffer);

            // Act
            var text = textChange.NewText;

            // Assert
            Assert.Equal(string.Empty, text);
        }

        [Fact]
        public void NewTextWithReplaceReturnsChangedTextFromBuffer()
        {
            // Arrange
            var newBuffer = new StringTextBuffer("test");
            var oldBuffer = new StringTextBuffer("tebb");
            var textChange = new TextChange(2, 2, oldBuffer, 1, newBuffer);

            // Act
            var newText = textChange.NewText;
            var oldText = textChange.OldText;

            // Assert
            Assert.Equal("s", newText);
            Assert.Equal("bb", oldText);
        }

        [Fact]
        public void ApplyChangeWithInsertedTextReturnsNewContentWithChangeApplied()
        {
            // Arrange
            var newBuffer = new StringTextBuffer("test");
            var oldBuffer = new StringTextBuffer("");
            var textChange = new TextChange(0, 0, oldBuffer, 3, newBuffer);

            // Act
            var text = textChange.ApplyChange("abcd", 0);

            // Assert
            Assert.Equal("tesabcd", text);
        }

        [Fact]
        public void ApplyChangeWithRemovedTextReturnsNewContentWithChangeApplied()
        {
            // Arrange
            var newBuffer = new StringTextBuffer("abcdefg");
            var oldBuffer = new StringTextBuffer("");
            var textChange = new TextChange(1, 1, oldBuffer, 0, newBuffer);

            // Act
            var text = textChange.ApplyChange("abcdefg", 1);

            // Assert
            Assert.Equal("bcdefg", text);
        }

        [Fact]
        public void ApplyChangeWithReplacedTextReturnsNewContentWithChangeApplied()
        {
            // Arrange
            var newBuffer = new StringTextBuffer("abcdefg");
            var oldBuffer = new StringTextBuffer("");
            var textChange = new TextChange(1, 1, oldBuffer, 2, newBuffer);

            // Act
            var text = textChange.ApplyChange("abcdefg", 1);

            // Assert
            Assert.Equal("bcbcdefg", text);
        }

        [Fact]
        public void NormalizeFixesUpIntelliSenseStyleReplacements()
        {
            // Arrange
            var newBuffer = new StringTextBuffer("Date.");
            var oldBuffer = new StringTextBuffer("Date");
            var original = new TextChange(0, 4, oldBuffer, 5, newBuffer);

            // Act
            var normalized = original.Normalize();

            // Assert
            Assert.Equal(new TextChange(4, 0, oldBuffer, 1, newBuffer), normalized);
        }

        [Fact]
        public void NormalizeDoesntAffectChangesWithoutCommonPrefixes()
        {
            // Arrange
            var newBuffer = new StringTextBuffer("DateTime.");
            var oldBuffer = new StringTextBuffer("Date.");
            var original = new TextChange(0, 5, oldBuffer, 9, newBuffer);

            // Act
            var normalized = original.Normalize();

            // Assert
            Assert.Equal(original, normalized);
        }

        [Fact]
        public void NormalizeDoesntAffectShrinkingReplacements()
        {
            // Arrange
            var newBuffer = new StringTextBuffer("D");
            var oldBuffer = new StringTextBuffer("DateTime");
            var original = new TextChange(0, 8, oldBuffer, 1, newBuffer);

            // Act
            var normalized = original.Normalize();

            // Assert
            Assert.Equal(original, normalized);
        }
    }
}