Implement logger

culminating-mastermind/app/src/main/java/mastermind/utils/ANSIColor.java

@@ -0,0 +1,27 @@
+package mastermind.utils;
+
+import java.util.Map;
+
+public enum ANSIColor {
+    RESET,
+    CYAN,
+    GRAY,
+    GREEN,
+    RED,
+    RED_BACKGROUND,
+    YELLOW;
+
+    private static final Map<ANSIColor, String> colorMap = Map.of(
+        RESET, "\u001B[0m",
+        CYAN, "\u001B[36m",
+        GRAY, "\u001B[90m",
+        GREEN, "\u001B[32m",
+        RED, "\u001B[31m",
+        RED_BACKGROUND, "\u001B[41m",
+        YELLOW, "\u001B[33m"
+    );
+
+    public static String colorize(final ANSIColor color, final String msg) {
+        return colorMap.get(color) + msg + colorMap.get(RESET);
+    }
+}

culminating-mastermind/app/src/main/java/mastermind/utils/Logger.java

@@ -0,0 +1,95 @@
+package mastermind.utils;
+
+import java.io.IOException;
+import java.io.OutputStream;
+import java.time.Instant;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Map;
+
+public class Logger {
+    private final ArrayList<OutputStream> sinks = new ArrayList<>(List.of(System.out));
+    private Severity level = Severity.INFO;
+
+    @SuppressWarnings("unused")
+    public void addSink(final OutputStream sink) {
+        sinks.add(sink);
+    }
+
+    @SuppressWarnings("unused")
+    public void setLevel(final Severity level) {
+        this.level = level;
+    }
+
+    @SuppressWarnings("unused")
+    public void trace(final String msg) {
+        log(Severity.TRACE, msg);
+    }
+
+    @SuppressWarnings("unused")
+    public void debug(final String msg) {
+        log(Severity.DEBUG, msg);
+    }
+
+    @SuppressWarnings("unused")
+    public void info(final String msg) {
+        log(Severity.INFO, msg);
+    }
+
+    @SuppressWarnings("unused")
+    public void warning(final String msg) {
+        log(Severity.WARNING, msg);
+    }
+
+    @SuppressWarnings("unused")
+    public void error(final String msg) {
+        log(Severity.ERROR, msg);
+    }
+
+    @SuppressWarnings("unused")
+    public void fatal(final String msg) {
+        log(Severity.FATAL, msg);
+        System.exit(1);
+    }
+
+    private void log(final Severity severity, final String msg) {
+        if (severity.ordinal() < level.ordinal()) {
+            return;
+        }
+
+        final Instant now = Instant.now();
+
+        final String formattedMsg = String.format("[%s][%s] %s%n", now.toString(), severity, msg);
+
+        for (OutputStream sink : sinks) {
+            try {
+                sink.write(formattedMsg.getBytes());
+            } catch (final IOException e) {
+                System.err.println(e.getMessage());
+            }
+        }
+    }
+
+    public enum Severity {
+        TRACE,
+        DEBUG,
+        INFO,
+        WARNING,
+        ERROR,
+        FATAL;
+
+        final static Map<Severity, ANSIColor> colorMap = Map.of(
+            TRACE, ANSIColor.GRAY,
+            DEBUG, ANSIColor.GREEN,
+            INFO, ANSIColor.CYAN,
+            WARNING, ANSIColor.YELLOW,
+            ERROR, ANSIColor.RED,
+            FATAL, ANSIColor.RED_BACKGROUND
+        );
+
+        @Override
+        public String toString() {
+            return ANSIColor.colorize(colorMap.get(this), super.toString());
+        }
+    }
+}