/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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.apache.juneau.terminal.report;

import java.nio.file.*;
import java.util.*;
import java.util.regex.*;

/**
 * Text helpers shared by the report readers.
 */
public final class ReportText {

   private static final Pattern ANSI = Pattern.compile("\u001b\\[[0-9;]*[A-Za-z]");

   private ReportText() {}

   /**
    * Removes ANSI escape sequences (test runners colour their messages).
    *
    * @param s The text.  May be <jk>null</jk>.
    * @return The text without escape sequences, or an empty string for <jk>null</jk>.
    */
   public static String stripAnsi(String s) {
      return s == null ? "" : ANSI.matcher(s).replaceAll("");
   }

   /**
    * Truncates a string to at most {@code max} chars, ending in an ellipsis when it was cut.
    *
    * @param s The text.  May be <jk>null</jk>.
    * @param max The maximum length, at least 1.
    * @return The clipped text, or an empty string for <jk>null</jk>.
    */
   public static String clip(String s, int max) {
      if (s == null)
         return "";
      return s.length() <= max ? s : s.substring(0, Math.max(0, max - 1)) + "…";
   }

   /**
    * Returns the file name of a path, never the directories (warnings leave the machine).
    *
    * @param path The path.
    * @return The last segment, or an empty string.
    */
   public static String fileName(Path path) {
      var n = path == null ? null : path.getFileName();
      return n == null ? "" : n.toString();
   }

   /**
    * Shortens a list of test file paths for display.
    *
    * <p>
    * Backslashes become slashes, then the longest common <i>directory</i> prefix of all paths is removed, so
    * {@code /ci/work/repo/src/a.test.js} and {@code /ci/work/repo/src/b/c.test.js} become {@code a.test.js} and
    * {@code b/c.test.js}.  A list with a single path keeps its last two segments ({@code src/a.test.js}).
    *
    * @param paths The paths.
    * @return The display paths, in the same order.
    */
   public static List<String> stripCommonDir(List<String> paths) {
      var segs = paths.stream().map(p -> p.replace('\\', '/').split("/", -1)).toList();
      var out = new ArrayList<String>(paths.size());
      if (segs.isEmpty())
         return out;
      if (segs.size() == 1) {
         var s = segs.get(0);
         out.add(String.join("/", Arrays.copyOfRange(s, Math.max(0, s.length - 2), s.length)));
         return out;
      }
      var common = Integer.MAX_VALUE;
      for (var s : segs)
         common = Math.min(common, s.length - 1);
      var first = segs.get(0);
      var keep = 0;
      while (keep < common && allEqual(segs, first[keep], keep))
         keep++;
      var drop = keep;
      out.addAll(segs.stream().map(s -> String.join("/", Arrays.copyOfRange(s, drop, s.length))).toList());
      return out;
   }

   private static boolean allEqual(List<String[]> segs, String value, int index) {
      for (var s : segs)
         if (! s[index].equals(value))
            return false;
      return true;
   }
}