Added initial support for rendering composites

This is far from complete, but it's a start
and it will enable us to create things like tables
and other complex objects in the long run.

src/Spectre.Console/Internal/Ansi/AnsiDetector.cs

@@ -13,7 +13,7 @@ namespace Spectre.Console.Internal
 {
     internal static class AnsiDetector
     {
-        private static readonly Regex[] Regexes = new[]
+        private static readonly Regex[] _regexes = new[]
         {
             new Regex("^xterm"), // xterm, PuTTY, Mintty
             new Regex("^rxvt"), // RXVT
@@ -32,7 +32,7 @@ namespace Spectre.Console.Internal
             new Regex("bvterm"), // Bitvise SSH Client
         };
 
-        public static bool SupportsAnsi(bool upgrade)
+        public static bool Detect(bool upgrade)
         {
             // Github action doesn't setup a correct PTY but supports ANSI.
             if (!string.IsNullOrWhiteSpace(Environment.GetEnvironmentVariable("GITHUB_ACTION")))
@@ -57,7 +57,7 @@ namespace Spectre.Console.Internal
             var term = Environment.GetEnvironmentVariable("TERM");
             if (!string.IsNullOrWhiteSpace(term))
             {
-                if (Regexes.Any(regex => regex.IsMatch(term)))
+                if (_regexes.Any(regex => regex.IsMatch(term)))
                 {
                     return true;
                 }
@@ -71,8 +71,10 @@ namespace Spectre.Console.Internal
         {
             [SuppressMessage("StyleCop.CSharp.NamingRules", "SA1310:Field names should not contain underscore")]
             private const int STD_OUTPUT_HANDLE = -11;
+
             [SuppressMessage("StyleCop.CSharp.NamingRules", "SA1310:Field names should not contain underscore")]
             private const uint ENABLE_VIRTUAL_TERMINAL_PROCESSING = 0x0004;
+
             [SuppressMessage("StyleCop.CSharp.NamingRules", "SA1310:Field names should not contain underscore")]
             private const uint DISABLE_NEWLINE_AUTO_RETURN = 0x0008;
 
@@ -94,7 +96,7 @@ namespace Spectre.Console.Internal
                 try
                 {
                     var @out = GetStdHandle(STD_OUTPUT_HANDLE);
-                    if (!GetConsoleMode(@out, out uint mode))
+                    if (!GetConsoleMode(@out, out var mode))
                     {
                         // Could not get console mode.
                         return false;

src/Spectre.Console/Internal/AnsiConsoleRenderer.cs

@@ -1,5 +1,6 @@
 using System;
 using System.IO;
+using System.Text;
 
 namespace Spectre.Console.Internal
 {
@@ -8,7 +9,8 @@ namespace Spectre.Console.Internal
         private readonly TextWriter _out;
         private readonly ColorSystem _system;
 
-        public AnsiConsoleCapabilities Capabilities { get; }
+        public Capabilities Capabilities { get; }
+        public Encoding Encoding { get; }
         public Styles Style { get; set; }
         public Color Foreground { get; set; }
         public Color Background { get; set; }
@@ -44,7 +46,8 @@ namespace Spectre.Console.Internal
             _out = @out ?? throw new ArgumentNullException(nameof(@out));
             _system = system;
 
-            Capabilities = new AnsiConsoleCapabilities(true, system);
+            Capabilities = new Capabilities(true, system);
+            Encoding = @out.IsStandardOut() ? System.Console.OutputEncoding : Encoding.UTF8;
             Foreground = Color.Default;
             Background = Color.Default;
             Style = Styles.None;
@@ -73,7 +76,7 @@ namespace Spectre.Console.Internal
 
             _out.Write(AnsiBuilder.GetAnsi(
                 _system,
-                text,
+                text.NormalizeLineEndings(native: true),
                 Style,
                 Foreground,
                 Background));

src/Spectre.Console/Internal/ConsoleBuilder.cs

@@ -14,7 +14,7 @@ namespace Spectre.Console.Internal
             var buffer = settings.Out ?? System.Console.Out;
 
             var supportsAnsi = settings.Ansi == AnsiSupport.Detect
-                ? AnsiDetector.SupportsAnsi(true)
+                ? AnsiDetector.Detect(true)
                 : settings.Ansi == AnsiSupport.Yes;
 
             var colorSystem = settings.ColorSystem == ColorSystemSupport.Detect

src/Spectre.Console/Internal/Extensions/CharExtensions.cs

@@ -0,0 +1,12 @@
+using System.Text;
+
+namespace Spectre.Console.Internal
+{
+    internal static class CharExtensions
+    {
+        public static int CellLength(this char token, Encoding encoding)
+        {
+            return Cell.GetCellLength(encoding, token);
+        }
+    }
+}

src/Spectre.Console/Internal/Extensions/ConsoleExtensions.cs

@@ -1,10 +1,25 @@
 using System;
 using System.Diagnostics.CodeAnalysis;
+using Spectre.Console.Composition;
 
 namespace Spectre.Console.Internal
 {
     internal static class ConsoleExtensions
     {
+        public static IDisposable PushAppearance(this IAnsiConsole console, Appearance appearance)
+        {
+            if (console is null)
+            {
+                throw new ArgumentNullException(nameof(console));
+            }
+
+            var current = new Appearance(console.Foreground, console.Background, console.Style);
+            console.SetColor(appearance.Foreground, true);
+            console.SetColor(appearance.Background, false);
+            console.Style = appearance.Style;
+            return new AppearanceScope(console, current);
+        }
+
         public static IDisposable PushColor(this IAnsiConsole console, Color color, bool foreground)
         {
             if (console is null)
@@ -47,6 +62,33 @@ namespace Spectre.Console.Internal
         }
     }
 
+    internal sealed class AppearanceScope : IDisposable
+    {
+        private readonly IAnsiConsole _console;
+        private readonly Appearance _apperance;
+
+        public AppearanceScope(IAnsiConsole console, Appearance appearance)
+        {
+            _console = console ?? throw new ArgumentNullException(nameof(console));
+            _apperance = appearance;
+        }
+
+        [SuppressMessage("Design", "CA1065:Do not raise exceptions in unexpected locations")]
+        [SuppressMessage("Performance", "CA1821:Remove empty Finalizers")]
+        ~AppearanceScope()
+        {
+            throw new InvalidOperationException("Appearance scope was not disposed.");
+        }
+
+        public void Dispose()
+        {
+            GC.SuppressFinalize(this);
+            _console.SetColor(_apperance.Foreground, true);
+            _console.SetColor(_apperance.Background, false);
+            _console.Style = _apperance.Style;
+        }
+    }
+
     internal sealed class ColorScope : IDisposable
     {
         private readonly IAnsiConsole _console;

src/Spectre.Console/Internal/Extensions/StringExtensions.cs

@@ -0,0 +1,36 @@
+using System;
+using System.Text;
+
+namespace Spectre.Console.Internal
+{
+    internal static class StringExtensions
+    {
+        // Cache whether or not internally normalized line endings
+        // already are normalized. No reason to do yet another replace if it is.
+        private static readonly bool _alreadyNormalized
+            = Environment.NewLine.Equals("\n", StringComparison.OrdinalIgnoreCase);
+
+        public static int CellLength(this string text, Encoding encoding)
+        {
+            return Cell.GetCellLength(encoding, text);
+        }
+
+        public static string NormalizeLineEndings(this string text, bool native = false)
+        {
+            var normalized = text?.Replace("\r\n", "\n")
+                ?.Replace("\r", string.Empty);
+
+            if (native && !_alreadyNormalized)
+            {
+                normalized = normalized.Replace("\n", Environment.NewLine);
+            }
+
+            return normalized;
+        }
+
+        public static string[] SplitLines(this string text)
+        {
+            return text.NormalizeLineEndings().Split(new[] { '\n' }, StringSplitOptions.None);
+        }
+    }
+}

src/Spectre.Console/Internal/FallbackConsoleRenderer.cs

@@ -1,5 +1,6 @@
 using System;
 using System.IO;
+using System.Text;
 
 namespace Spectre.Console.Internal
 {
@@ -13,7 +14,9 @@ namespace Spectre.Console.Internal
         private ConsoleColor _foreground;
         private ConsoleColor _background;
 
-        public AnsiConsoleCapabilities Capabilities { get; }
+        public Capabilities Capabilities { get; }
+
+        public Encoding Encoding { get; }
 
         public int Width
         {
@@ -87,23 +90,27 @@ namespace Spectre.Console.Internal
             _out = @out;
             _system = system;
 
-            Capabilities = new AnsiConsoleCapabilities(false, _system);
-
             if (_out.IsStandardOut())
             {
                 _defaultForeground = System.Console.ForegroundColor;
                 _defaultBackground = System.Console.BackgroundColor;
+
+                Encoding = System.Console.OutputEncoding;
             }
             else
             {
                 _defaultForeground = ConsoleColor.Gray;
                 _defaultBackground = ConsoleColor.Black;
+
+                Encoding = Encoding.UTF8;
             }
+
+            Capabilities = new Capabilities(false, _system);
         }
 
         public void Write(string text)
         {
-            _out.Write(text);
+            _out.Write(text.NormalizeLineEndings(native: true));
         }
     }
 }

src/Spectre.Console/Internal/Text/Cell.cs

@@ -0,0 +1,150 @@
+// Taken and modified from NStack project by Miguel de Icaza, licensed under BSD-3
+// https://github.com/migueldeicaza/NStack/blob/3fc024fb2c2e99927d3e12991570fb54db8ce01e/NStack/unicode/Rune.ColumnWidth.cs
+
+using System.Diagnostics.CodeAnalysis;
+using System.Linq;
+using System.Text;
+
+namespace Spectre.Console.Internal
+{
+    internal static class Cell
+    {
+        [SuppressMessage("Design", "RCS1169:Make field read-only.")]
+        [SuppressMessage("StyleCop.CSharp.LayoutRules", "SA1500:Braces for multi-line statements should not share line")]
+        private static readonly uint[,] _combining = new uint[,]
+        {
+            { 0x0300, 0x036F }, { 0x0483, 0x0486 }, { 0x0488, 0x0489 },
+            { 0x0591, 0x05BD }, { 0x05BF, 0x05BF }, { 0x05C1, 0x05C2 },
+            { 0x05C4, 0x05C5 }, { 0x05C7, 0x05C7 }, { 0x0600, 0x0603 },
+            { 0x0610, 0x0615 }, { 0x064B, 0x065E }, { 0x0670, 0x0670 },
+            { 0x06D6, 0x06E4 }, { 0x06E7, 0x06E8 }, { 0x06EA, 0x06ED },
+            { 0x070F, 0x070F }, { 0x0711, 0x0711 }, { 0x0730, 0x074A },
+            { 0x07A6, 0x07B0 }, { 0x07EB, 0x07F3 }, { 0x0901, 0x0902 },
+            { 0x093C, 0x093C }, { 0x0941, 0x0948 }, { 0x094D, 0x094D },
+            { 0x0951, 0x0954 }, { 0x0962, 0x0963 }, { 0x0981, 0x0981 },
+            { 0x09BC, 0x09BC }, { 0x09C1, 0x09C4 }, { 0x09CD, 0x09CD },
+            { 0x09E2, 0x09E3 }, { 0x0A01, 0x0A02 }, { 0x0A3C, 0x0A3C },
+            { 0x0A41, 0x0A42 }, { 0x0A47, 0x0A48 }, { 0x0A4B, 0x0A4D },
+            { 0x0A70, 0x0A71 }, { 0x0A81, 0x0A82 }, { 0x0ABC, 0x0ABC },
+            { 0x0AC1, 0x0AC5 }, { 0x0AC7, 0x0AC8 }, { 0x0ACD, 0x0ACD },
+            { 0x0AE2, 0x0AE3 }, { 0x0B01, 0x0B01 }, { 0x0B3C, 0x0B3C },
+            { 0x0B3F, 0x0B3F }, { 0x0B41, 0x0B43 }, { 0x0B4D, 0x0B4D },
+            { 0x0B56, 0x0B56 }, { 0x0B82, 0x0B82 }, { 0x0BC0, 0x0BC0 },
+            { 0x0BCD, 0x0BCD }, { 0x0C3E, 0x0C40 }, { 0x0C46, 0x0C48 },
+            { 0x0C4A, 0x0C4D }, { 0x0C55, 0x0C56 }, { 0x0CBC, 0x0CBC },
+            { 0x0CBF, 0x0CBF }, { 0x0CC6, 0x0CC6 }, { 0x0CCC, 0x0CCD },
+            { 0x0CE2, 0x0CE3 }, { 0x0D41, 0x0D43 }, { 0x0D4D, 0x0D4D },
+            { 0x0DCA, 0x0DCA }, { 0x0DD2, 0x0DD4 }, { 0x0DD6, 0x0DD6 },
+            { 0x0E31, 0x0E31 }, { 0x0E34, 0x0E3A }, { 0x0E47, 0x0E4E },
+            { 0x0EB1, 0x0EB1 }, { 0x0EB4, 0x0EB9 }, { 0x0EBB, 0x0EBC },
+            { 0x0EC8, 0x0ECD }, { 0x0F18, 0x0F19 }, { 0x0F35, 0x0F35 },
+            { 0x0F37, 0x0F37 }, { 0x0F39, 0x0F39 }, { 0x0F71, 0x0F7E },
+            { 0x0F80, 0x0F84 }, { 0x0F86, 0x0F87 }, { 0x0F90, 0x0F97 },
+            { 0x0F99, 0x0FBC }, { 0x0FC6, 0x0FC6 }, { 0x102D, 0x1030 },
+            { 0x1032, 0x1032 }, { 0x1036, 0x1037 }, { 0x1039, 0x1039 },
+            { 0x1058, 0x1059 }, { 0x1160, 0x11FF }, { 0x135F, 0x135F },
+            { 0x1712, 0x1714 }, { 0x1732, 0x1734 }, { 0x1752, 0x1753 },
+            { 0x1772, 0x1773 }, { 0x17B4, 0x17B5 }, { 0x17B7, 0x17BD },
+            { 0x17C6, 0x17C6 }, { 0x17C9, 0x17D3 }, { 0x17DD, 0x17DD },
+            { 0x180B, 0x180D }, { 0x18A9, 0x18A9 }, { 0x1920, 0x1922 },
+            { 0x1927, 0x1928 }, { 0x1932, 0x1932 }, { 0x1939, 0x193B },
+            { 0x1A17, 0x1A18 }, { 0x1B00, 0x1B03 }, { 0x1B34, 0x1B34 },
+            { 0x1B36, 0x1B3A }, { 0x1B3C, 0x1B3C }, { 0x1B42, 0x1B42 },
+            { 0x1B6B, 0x1B73 }, { 0x1DC0, 0x1DCA }, { 0x1DFE, 0x1DFF },
+            { 0x200B, 0x200F }, { 0x202A, 0x202E }, { 0x2060, 0x2063 },
+            { 0x206A, 0x206F }, { 0x20D0, 0x20EF }, { 0x302A, 0x302F },
+            { 0x3099, 0x309A }, { 0xA806, 0xA806 }, { 0xA80B, 0xA80B },
+            { 0xA825, 0xA826 }, { 0xFB1E, 0xFB1E }, { 0xFE00, 0xFE0F },
+            { 0xFE20, 0xFE23 }, { 0xFEFF, 0xFEFF }, { 0xFFF9, 0xFFFB },
+            { 0x10A01, 0x10A03 }, { 0x10A05, 0x10A06 }, { 0x10A0C, 0x10A0F },
+            { 0x10A38, 0x10A3A }, { 0x10A3F, 0x10A3F }, { 0x1D167, 0x1D169 },
+            { 0x1D173, 0x1D182 }, { 0x1D185, 0x1D18B }, { 0x1D1AA, 0x1D1AD },
+            { 0x1D242, 0x1D244 }, { 0xE0001, 0xE0001 }, { 0xE0020, 0xE007F },
+            { 0xE0100, 0xE01EF },
+        };
+
+        public static int GetCellLength(Encoding encoding, string text)
+        {
+            return text.Sum(c => GetCellLength(encoding, c));
+        }
+
+        public static int GetCellLength(Encoding encoding, char rune)
+        {
+            // Is it represented by a single byte?
+            // In that case we don't have to calculate the
+            // actual cell width.
+            if (encoding.GetByteCount(new[] { rune }) == 1)
+            {
+                return 1;
+            }
+
+            var irune = (uint)rune;
+            if (irune < 32)
+            {
+                return 0;
+            }
+
+            if (irune < 127)
+            {
+                return 1;
+            }
+
+            if (irune >= 0x7f && irune <= 0xa0)
+            {
+                return 0;
+            }
+
+            // Binary search in table of non-spacing characters
+            if (BinarySearch(irune, _combining, _combining.GetLength(0) - 1) != 0)
+            {
+                return 0;
+            }
+
+            // If we arrive here, ucs is not a combining or C0/C1 control character
+            return 1 +
+                ((irune >= 0x1100 &&
+                 (irune <= 0x115f || /* Hangul Jamo init. consonants */
+                irune == 0x2329 || irune == 0x232a ||
+                (irune >= 0x2e80 && irune <= 0xa4cf &&
+                irune != 0x303f) || /* CJK ... Yi */
+                (irune >= 0xac00 && irune <= 0xd7a3) || /* Hangul Syllables */
+                (irune >= 0xf900 && irune <= 0xfaff) || /* CJK Compatibility Ideographs */
+                (irune >= 0xfe10 && irune <= 0xfe19) || /* Vertical forms */
+                (irune >= 0xfe30 && irune <= 0xfe6f) || /* CJK Compatibility Forms */
+                (irune >= 0xff00 && irune <= 0xff60) || /* Fullwidth Forms */
+                (irune >= 0xffe0 && irune <= 0xffe6) ||
+                (irune >= 0x20000 && irune <= 0x2fffd) ||
+                  (irune >= 0x30000 && irune <= 0x3fffd))) ? 1 : 0);
+        }
+
+        private static int BinarySearch(uint rune, uint[,] table, int max)
+        {
+            var min = 0;
+            int mid;
+
+            if (rune < table[0, 0] || rune > table[max, 1])
+            {
+                return 0;
+            }
+
+            while (max >= min)
+            {
+                mid = (min + max) / 2;
+                if (rune > table[mid, 1])
+                {
+                    min = mid + 1;
+                }
+                else if (rune < table[mid, 0])
+                {
+                    max = mid - 1;
+                }
+                else
+                {
+                    return 1;
+                }
+            }
+
+            return 0;
+        }
+    }
+}