/*
    * 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.eclipse.aether.util.version;
  
  import java.util.Objects;
  
  import org.eclipse.aether.version.InvalidVersionSpecificationException;
  import org.eclipse.aether.version.Version;
  import org.eclipse.aether.version.VersionRange;
  
  import static java.util.Objects.requireNonNull;
  
  /**
   * A version range inspired by mathematical range syntax. For example, "[1.0,2.0)", "[1.0,)" or "[1.0]".
   */
  final class GenericVersionRange implements VersionRange {
  
      private final Bound lowerBound;
  
      private final Bound upperBound;
  
      /**
       * Creates a version range from the specified range specification.
       *
       * @param range The range specification to parse, must not be {@code null}.
       * @throws InvalidVersionSpecificationException If the range could not be parsed.
       */
      GenericVersionRange(String range) throws InvalidVersionSpecificationException {
          String process = requireNonNull(range, "version range cannot be null");
  
          boolean lowerBoundInclusive, upperBoundInclusive;
          Version lowerBound, upperBound;
  
          if (range.startsWith("[")) {
              lowerBoundInclusive = true;
          } else if (range.startsWith("(")) {
              lowerBoundInclusive = false;
          } else {
              throw new InvalidVersionSpecificationException(
                      range, "Invalid version range " + range + ", a range must start with either [ or (");
          }
  
          if (range.endsWith("]")) {
              upperBoundInclusive = true;
          } else if (range.endsWith(")")) {
              upperBoundInclusive = false;
          } else {
              throw new InvalidVersionSpecificationException(
                      range, "Invalid version range " + range + ", a range must end with either [ or (");
          }
  
          process = process.substring(1, process.length() - 1);
  
          int index = process.indexOf(",");
  
          if (index < 0) {
              if (!lowerBoundInclusive || !upperBoundInclusive) {
                  throw new InvalidVersionSpecificationException(
                          range, "Invalid version range " + range + ", single version must be surrounded by []");
              }
  
              String version = process.trim();
              if (version.endsWith(".*")) {
                  String prefix = version.substring(0, version.length() - 1);
                  lowerBound = parse(prefix + "min");
                  upperBound = parse(prefix + "max");
              } else {
                  lowerBound = parse(version);
                  upperBound = lowerBound;
              }
          } else {
              String parsedLowerBound = process.substring(0, index).trim();
              String parsedUpperBound = process.substring(index + 1).trim();
  
              // more than two bounds, e.g. (1,2,3)
              if (parsedUpperBound.contains(",")) {
                  throw new InvalidVersionSpecificationException(
                          range, "Invalid version range " + range + ", bounds may not contain additional ','");
              }
  
              lowerBound = parsedLowerBound.length() > 0 ? parse(parsedLowerBound) : null;
              upperBound = parsedUpperBound.length() > 0 ? parse(parsedUpperBound) : null;
  
             if (upperBound != null && lowerBound != null) {
                 if (upperBound.compareTo(lowerBound) < 0) {
                     throw new InvalidVersionSpecificationException(
                             range,
                             "Invalid version range " + range + ", lower bound must not be greater than upper bound");
                 }
             }
         }
 
         this.lowerBound = (lowerBound != null) ? new Bound(lowerBound, lowerBoundInclusive) : null;
         this.upperBound = (upperBound != null) ? new Bound(upperBound, upperBoundInclusive) : null;
     }
 
     private Version parse(String version) {
         return new GenericVersion(version);
     }
 
     @Override
     public Bound getLowerBound() {
         return lowerBound;
     }
 
     @Override
     public Bound getUpperBound() {
         return upperBound;
     }
 
     @Override
     public boolean containsVersion(Version version) {
         if (lowerBound != null) {
             int comparison = lowerBound.getVersion().compareTo(version);
 
             if (comparison == 0 && !lowerBound.isInclusive()) {
                 return false;
             }
             if (comparison > 0) {
                 return false;
             }
         }
 
         if (upperBound != null) {
             int comparison = upperBound.getVersion().compareTo(version);
 
             if (comparison == 0 && !upperBound.isInclusive()) {
                 return false;
             }
             if (comparison < 0) {
                 return false;
             }
         }
 
         return true;
     }
 
     @Override
     public boolean equals(Object obj) {
         if (obj == this) {
             return true;
         } else if (obj == null || !getClass().equals(obj.getClass())) {
             return false;
         }
 
         GenericVersionRange that = (GenericVersionRange) obj;
 
         return Objects.equals(upperBound, that.upperBound) && Objects.equals(lowerBound, that.lowerBound);
     }
 
     @Override
     public int hashCode() {
         int hash = 17;
         hash = hash * 31 + hash(upperBound);
         hash = hash * 31 + hash(lowerBound);
         return hash;
     }
 
     private static int hash(Object obj) {
         return obj != null ? obj.hashCode() : 0;
     }
 
     @Override
     public String toString() {
         StringBuilder buffer = new StringBuilder(64);
         if (lowerBound != null) {
             buffer.append(lowerBound.isInclusive() ? '[' : '(');
             buffer.append(lowerBound.getVersion());
         } else {
             buffer.append('(');
         }
         buffer.append(',');
         if (upperBound != null) {
             buffer.append(upperBound.getVersion());
             buffer.append(upperBound.isInclusive() ? ']' : ')');
         } else {
             buffer.append(')');
         }
         return buffer.toString();
     }
 }