256 colors and truecolor support

src/main/java/org/fusesource/jansi/Ansi.java

@@ -378,6 +378,26 @@ public Ansi fg(Color color) {
         return this;
     }
 
+    public Ansi fg(int color) {
+        attributeOptions.add(38);
+        attributeOptions.add(5);
+        attributeOptions.add(color & 0xff);
+        return this;
+    }
+
+    public Ansi fgRgb(int color) {
+        return fgRgb(color >> 16, color >> 8, color);
+    }
+
+    public Ansi fgRgb(int r, int g, int b) {
+        attributeOptions.add(38);
+        attributeOptions.add(2);
+        attributeOptions.add(r & 0xff);
+        attributeOptions.add(g & 0xff);
+        attributeOptions.add(b & 0xff);
+        return this;
+    }
+
     public Ansi fgBlack() {
         return this.fg(Color.BLACK);
     }
@@ -415,6 +435,26 @@ public Ansi bg(Color color) {
         return this;
     }
 
+    public Ansi bg(int color) {
+        attributeOptions.add(48);
+        attributeOptions.add(5);
+        attributeOptions.add(color & 0xff);
+        return this;
+    }
+
+    public Ansi bgRgb(int color) {
+        return bgRgb(color >> 16, color >> 8, color);
+    }
+
+    public Ansi bgRgb(int r, int g, int b) {
+        attributeOptions.add(48);
+        attributeOptions.add(2);
+        attributeOptions.add(r & 0xff);
+        attributeOptions.add(g & 0xff);
+        attributeOptions.add(b & 0xff);
+        return this;
+    }
+
     public Ansi bgCyan() {
         return this.bg(Color.CYAN);
     }

src/main/java/org/fusesource/jansi/AnsiColors.java

@@ -0,0 +1,38 @@
+/*
+ * Copyright (C) 2009-2017 the original author(s).
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.fusesource.jansi;
+
+/**
+ * Colors support.
+ *
+ * @since 2.1
+ */
+public enum AnsiColors {
+
+    Colors16("16 colors"),
+    Colors256("256 colors"),
+    TrueColor("24-bit colors");
+
+    private final String description;
+
+    AnsiColors(String description) {
+        this.description = description;
+    }
+
+    String getDescription() {
+        return description;
+    }
+}

src/main/java/org/fusesource/jansi/AnsiConsole.java

@@ -85,6 +85,37 @@ public class AnsiConsole {
      */
     public static final String JANSI_MODE_DEFAULT = "default";
 
+    /**
+     * The default color support that Jansi will use, can be either <code>16</code>,
+     * <code>256</code> or <code>truecolor</code>.  If not set, JANSI will try to
+     * autodetect the number of colors supported by the terminal by checking the
+     * <code>COLORTERM</code> and <code>TERM</code> variables.
+     */
+    public static final String JANSI_COLORS = "jansi.colors";
+    /**
+     * Jansi colors specific to the standard output stream.
+     */
+    public static final String JANSI_OUT_COLORS = "jansi.out.colors";
+    /**
+     * Jansi colors specific to the standard error stream.
+     */
+    public static final String JANSI_ERR_COLORS = "jansi.err.colors";
+
+    /**
+     * Force the use of 16 colors. When using a 256-indexed color, or an RGB
+     * color, the color will be rounded to the nearest one from the 16 palette.
+     */
+    public static final String JANSI_COLORS_16 = "16";
+    /**
+     * Force the use of 256 colors. When using an RGB color, the color will be
+     * rounded to the nearest one from the standard 256 palette.
+     */
+    public static final String JANSI_COLORS_256 = "256";
+    /**
+     * Force the use of 24-bit colors.
+     */
+    public static final String JANSI_COLORS_TRUECOLOR = "truecolor";
+
     /**
      * If the <code>jansi.passthrough</code> system property is set to true, will not perform any transformation
      * and any ansi sequence will be conveyed without any modification.
@@ -300,6 +331,41 @@ else if (getBoolean(JANSI_FORCE)) {
             mode = isatty ? AnsiMode.Default : AnsiMode.Strip;
         }
 
+        AnsiColors colors;
+
+        String colorterm, term;
+        // If the jansi.colors property is set, use it
+        String jansiColors = System.getProperty(stdout ? JANSI_OUT_COLORS : JANSI_ERR_COLORS, System.getProperty(JANSI_COLORS));
+        if (JANSI_COLORS_TRUECOLOR.equals(jansiColors)) {
+            colors = AnsiColors.TrueColor;
+        } else if (JANSI_COLORS_256.equals(jansiColors)) {
+            colors = AnsiColors.Colors256;
+        } else if (jansiColors != null) {
+            colors = AnsiColors.Colors16;
+        }
+
+        // If the COLORTERM env variable contains "truecolor" or "24bit", assume true color support
+        // see https://gist.github.com/XVilka/8346728#true-color-detection
+        else if ((colorterm = System.getenv("COLORTERM")) != null
+                && (colorterm.contains("truecolor") || colorterm.contains("24bit"))) {
+            colors = AnsiColors.TrueColor;
+        }
+
+        // check the if TERM contains -direct
+        else if ((term = System.getenv("TERM")) != null && term.contains("-direct")) {
+            colors = AnsiColors.TrueColor;
+        }
+
+        // check the if TERM contains -256color
+        else if (term != null && term.contains("-256color")) {
+            colors = AnsiColors.Colors256;
+        }
+
+        // else defaults to 16 colors
+        else {
+            colors = AnsiColors.Colors16;
+        }
+
         // If the jansi.noreset property is not set, reset the attributes
         // when the stream is closed
         boolean resetAtUninstall = !getBoolean(JANSI_NORESET);
@@ -311,7 +377,7 @@ else if (getBoolean(JANSI_FORCE)) {
             } catch (UnsupportedCharsetException e) {
             }
         }
-        return newPrintStream(new AnsiOutputStream(out, mode, processor, type, cs,
+        return newPrintStream(new AnsiOutputStream(out, mode, processor, type, colors, cs,
                 installer, uninstaller, resetAtUninstall), cs.name());
     }
 

src/main/java/org/fusesource/jansi/AnsiMain.java

@@ -77,6 +77,9 @@ public static void main(String... args) throws IOException {
         System.out.println(AnsiConsole.JANSI_MODE + "= " + System.getProperty(AnsiConsole.JANSI_MODE, ""));
         System.out.println(AnsiConsole.JANSI_OUT_MODE + "= " + System.getProperty(AnsiConsole.JANSI_OUT_MODE, ""));
         System.out.println(AnsiConsole.JANSI_ERR_MODE + "= " + System.getProperty(AnsiConsole.JANSI_ERR_MODE, ""));
+        System.out.println(AnsiConsole.JANSI_COLORS + "= " + System.getProperty(AnsiConsole.JANSI_COLORS, ""));
+        System.out.println(AnsiConsole.JANSI_OUT_COLORS + "= " + System.getProperty(AnsiConsole.JANSI_OUT_COLORS, ""));
+        System.out.println(AnsiConsole.JANSI_ERR_COLORS + "= " + System.getProperty(AnsiConsole.JANSI_ERR_COLORS, ""));
         System.out.println(AnsiConsole.JANSI_PASSTHROUGH + "= " + AnsiConsole.getBoolean(AnsiConsole.JANSI_PASSTHROUGH));
         System.out.println(AnsiConsole.JANSI_STRIP + "= " + AnsiConsole.getBoolean(AnsiConsole.JANSI_STRIP));
         System.out.println(AnsiConsole.JANSI_FORCE + "= " + AnsiConsole.getBoolean(AnsiConsole.JANSI_FORCE));
@@ -108,6 +111,10 @@ public static void main(String... args) throws IOException {
         for (AnsiType type : AnsiType.values()) {
             System.out.println("  - " + type + ": " + type.getDescription());
         }
+        System.out.println("Colors support description:");
+        for (AnsiColors colors : AnsiColors.values()) {
+            System.out.println("  - " + colors + ": " + colors.getDescription());
+        }
         System.out.println("Modes description:");
         for (AnsiMode mode : AnsiMode.values()) {
             System.out.println("  - " + mode + ": " + mode.getDescription());
@@ -187,6 +194,39 @@ private static void testAnsi(boolean stderr) {
             s.print(" " + ansi().bold().fg(c) + c + ansi().reset());
         }
         s.println();
+        Ansi ansi = ansi();
+        ansi.a("        256 colors: ");
+        for (int i = 0; i < 6*6*6; i++) {
+            if (i > 0 && i % 36 == 0) {
+                ansi.reset();
+                ansi.newline();
+                ansi.a("                    ");
+            } else if (i > 0 && i % 6 == 0) {
+                ansi.reset();
+                ansi.a("  ");
+            }
+            int a0 = i % 6;
+            int a1 = (i  / 6) % 6;
+            int a2 = i / 36;
+            ansi.bg(16 + a0 + a2 * 6 + a1 * 36).a(' ');
+        }
+        ansi.reset();
+        s.println(ansi);
+        ansi = ansi();
+        ansi.a("         truecolor: ");
+        for (int i = 0; i < 256; i++) {
+            if (i > 0 && i % 48 == 0) {
+                ansi.reset();
+                ansi.newline();
+                ansi.a("                    ");
+            }
+            int r = 255 - i;
+            int g = i * 2 > 255 ? 255 - 2 * i : 2 * i;
+            int b = i;
+            ansi.bgRgb(r, g, b).fgRgb(255 - r, 255 - g, 255 - b).a(i % 2 == 0 ? '/' : '\\');
+        }
+        ansi.reset();
+        s.println(ansi);
     }
 
     private static String getPomPropertiesVersion(String path) throws IOException {

src/main/java/org/fusesource/jansi/AnsiPrintStream.java

@@ -43,6 +43,10 @@ public AnsiType getType() {
         return getOut().getType();
     }
 
+    public AnsiColors getColors() {
+        return getOut().getColors();
+    }
+
     public AnsiMode getMode() {
         return getOut().getMode();
     }
@@ -71,6 +75,7 @@ public void uninstall() throws IOException {
     public String toString() {
         return "AnsiPrintStream{"
                 + "type=" + getType()
+                + ", colors=" + getColors()
                 + ", mode=" + getMode()
                 + ", resetAtUninstall=" + isResetAtUninstall()
                 + "}";

src/main/java/org/fusesource/jansi/io/AnsiOutputStream.java

@@ -21,6 +21,7 @@
 import java.nio.charset.Charset;
 import java.util.ArrayList;
 
+import org.fusesource.jansi.AnsiColors;
 import org.fusesource.jansi.AnsiMode;
 import org.fusesource.jansi.AnsiType;
 
@@ -74,17 +75,19 @@ public interface IoRunnable {
 
     private final AnsiProcessor processor;
     private final AnsiType type;
+    private final AnsiColors colors;
     private final IoRunnable installer;
     private final IoRunnable uninstaller;
     private AnsiMode mode;
     private boolean resetAtUninstall;
 
     public AnsiOutputStream(OutputStream os, AnsiMode mode,
-                            AnsiProcessor processor, AnsiType type,
+                            AnsiProcessor processor, AnsiType type, AnsiColors colors,
                             Charset cs, IoRunnable installer, IoRunnable uninstaller, boolean resetAtUninstall) {
         super(os);
         this.processor = processor;
         this.type = type;
+        this.colors = colors;
         this.installer = installer;
         this.uninstaller = uninstaller;
         this.resetAtUninstall = resetAtUninstall;
@@ -96,12 +99,18 @@ public AnsiType getType() {
         return type;
     }
 
+    public AnsiColors getColors() {
+        return colors;
+    }
+
     public AnsiMode getMode() {
         return mode;
     }
 
     public void setMode(AnsiMode mode) {
-        ap = mode == AnsiMode.Strip ? new AnsiProcessor(out) : mode == AnsiMode.Force ? null : processor;
+        ap = mode == AnsiMode.Strip
+                ? new AnsiProcessor(out)
+                : mode == AnsiMode.Force || processor == null ? new ColorsAnsiProcessor(out, colors) : processor;
         this.mode = mode;
     }
 

src/main/java/org/fusesource/jansi/io/AnsiProcessor.java

@@ -20,6 +20,8 @@
 import java.util.ArrayList;
 import java.util.Iterator;
 
+import org.fusesource.jansi.AnsiColors;
+
 /**
  * ANSI processor providing <code>process*</code> corresponding to ANSI escape codes. 
  * This class methods implementations are empty: subclasses should actually perform the
@@ -43,7 +45,7 @@ public AnsiProcessor(OutputStream os) {
      * @param  optionsIterator  the underlying iterator
      * @throws IOException      if no more non-null values left
      */
-    private int getNextOptionInt(Iterator<Object> optionsIterator) throws IOException {
+    protected int getNextOptionInt(Iterator<Object> optionsIterator) throws IOException {
         for (;;) {
             if (!optionsIterator.hasNext())
                 throw new IllegalArgumentException();