// 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 Xunit;

namespace Microsoft.AspNetCore.Routing.Matching
{
    // Note that while we don't intend for this code to be used with non-ASCII test,
    // we still call into these methods with some non-ASCII characters so that
    // we are sure of how it behaves.
    public class AsciiTest
    {
        [Fact]
        public void IsAscii_ReturnsTrueForAscii()
        {
            // Arrange
            var text = "abcd\u007F";

            // Act
            var result = Ascii.IsAscii(text);

            // Assert
            Assert.True(result);
        }

        [Fact]
        public void IsAscii_ReturnsFalseForNonAscii()
        {
            // Arrange
            var text = "abcd\u0080";

            // Act
            var result = Ascii.IsAscii(text);

            // Assert
            Assert.False(result);
        }

        [Theory]

        // Identity
        [InlineData('c', 'c')]
        [InlineData('C', 'C')]
        [InlineData('#', '#')]
        [InlineData('\u0080', '\u0080')]

        // Case-insensitive
        [InlineData('c', 'C')]
        public void AsciiIgnoreCaseEquals_ReturnsTrue(char x, char y)
        {
            // Arrange
            
            // Act
            var result = Ascii.AsciiIgnoreCaseEquals(x, y);

            // Assert
            Assert.True(result);
        }

        [Theory]

        // Different letter
        [InlineData('c', 'd')]
        [InlineData('C', 'D')]

        // Non-letter + casing difference - 'a' and 'A' are 32 bits apart and so are ' ' and '@'
        [InlineData(' ', '@')] 
        [InlineData('\u0080', '\u0080' + 32)] // Outside of ASCII range
        public void AsciiIgnoreCaseEquals_ReturnsFalse(char x, char y)
        {
            // Arrange

            // Act
            var result = Ascii.AsciiIgnoreCaseEquals(x, y);

            // Assert
            Assert.False(result);
        }

        [Theory]
        [InlineData("", "", 0)]
        [InlineData("abCD", "abcF", 3)]
        [InlineData("ab#\u0080-$%", "Ab#\u0080-$%", 7)]
        public void UnsafeAsciiIgnoreCaseEquals_ReturnsTrue(string x, string y, int length)
        {
            // Arrange
            var spanX = x.AsSpan();
            var spanY = y.AsSpan();

            // Act
            var result = Ascii.AsciiIgnoreCaseEquals(spanX, spanY, length);

            // Assert
            Assert.True(result);
        }

        [Theory]
        [InlineData("abcD", "abCE", 4)]
        [InlineData("ab#\u0080-$%", "Ab#\u0081-$%", 7)]
        public void UnsafeAsciiIgnoreCaseEquals_ReturnsFalse(string x, string y, int length)
        {
            // Arrange
            var spanX = x.AsSpan();
            var spanY = y.AsSpan();

            // Act
            var result = Ascii.AsciiIgnoreCaseEquals(spanX, spanY, length);

            // Assert
            Assert.False(result);
        }
    }
}