/*
 * 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.tuscany.maven.bundle.plugin;

import java.util.StringTokenizer;

import org.apache.maven.artifact.versioning.ArtifactVersion;

public class OSGIArtifactVersion implements ArtifactVersion {
    private Integer buildNumber;

    private Integer incrementalVersion;

    private Integer majorVersion;

    private Integer minorVersion;

    private String qualifier;

    private String unparsed;

    public OSGIArtifactVersion(String version) {
        parseVersion(version);
    }

    public int compareTo(Object o) {
        ArtifactVersion otherVersion = (ArtifactVersion)o;

        int result = getMajorVersion() - otherVersion.getMajorVersion();
        if (result == 0) {
            result = getMinorVersion() - otherVersion.getMinorVersion();
        }
        if (result == 0) {
            result = getIncrementalVersion() - otherVersion.getIncrementalVersion();
        }
        if (result == 0) {
            if (this.qualifier != null) {
                String otherQualifier = otherVersion.getQualifier();

                if (otherQualifier != null) {
                    if ((this.qualifier.length() > otherQualifier.length()) && this.qualifier
                        .startsWith(otherQualifier)) {
                        // here, the longer one that otherwise match is
                        // considered older
                        result = -1;
                    } else if ((this.qualifier.length() < otherQualifier.length()) && otherQualifier
                        .startsWith(this.qualifier)) {
                        // here, the longer one that otherwise match is
                        // considered older
                        result = 1;
                    } else {
                        result = this.qualifier.compareTo(otherQualifier);
                    }
                } else {
                    // otherVersion has no qualifier but we do - that's newer
                    result = -1;
                }
            } else if (otherVersion.getQualifier() != null) {
                // otherVersion has a qualifier but we don't, we're newer
                result = 1;
            } else {
                result = getBuildNumber() - otherVersion.getBuildNumber();
            }
        }
        return result;
    }

    @Override
    public boolean equals(Object other) {
        if (this == other) {
            return true;
        }

        if (false == (other instanceof ArtifactVersion)) {
            return false;
        }

        return 0 == compareTo(other);
    }

    public int getBuildNumber() {
        return this.buildNumber != null ? this.buildNumber.intValue() : 0;
    }

    public int getIncrementalVersion() {
        return this.incrementalVersion != null ? this.incrementalVersion.intValue() : 0;
    }

    public int getMajorVersion() {
        return this.majorVersion != null ? this.majorVersion.intValue() : 0;
    }

    public int getMinorVersion() {
        return this.minorVersion != null ? this.minorVersion.intValue() : 0;
    }

    public String getQualifier() {
        return this.qualifier;
    }

    @Override
    public int hashCode() {
        int result = 1229;

        result = 1223 * result + getMajorVersion();
        result = 1223 * result + getMinorVersion();
        result = 1223 * result + getIncrementalVersion();
        result = 1223 * result + getBuildNumber();

        if (null != getQualifier()) {
            result = 1223 * result + getQualifier().hashCode();
        }

        return result;
    }

    public final void parseVersion(String version) {
        this.unparsed = version;

        int index = version.indexOf("-");

        String part1;
        String part2 = null;

        if (index < 0) {
            part1 = version;
        } else {
            part1 = version.substring(0, index);
            part2 = version.substring(index + 1);
        }

        if (part2 != null) {
            try {
                if ((part2.length() == 1) || !part2.startsWith("0")) {
                    this.buildNumber = Integer.valueOf(part2);
                } else {
                    this.qualifier = part2;
                }
            } catch (NumberFormatException e) {
                this.qualifier = part2;
            }
        }

        if ((part1.indexOf(".") < 0) && !part1.startsWith("0")) {
            try {
                this.majorVersion = Integer.valueOf(part1);
            } catch (NumberFormatException e) {
                // qualifier is the whole version, including "-"
                this.qualifier = version;
                this.buildNumber = null;
            }
        } else {
            StringTokenizer tok = new StringTokenizer(part1, ".");

            String s;

            if (tok.hasMoreTokens()) {
                s = tok.nextToken();
                try {
                    this.majorVersion = Integer.valueOf(s);

                    if (tok.hasMoreTokens()) {
                        s = tok.nextToken();
                        try {
                            this.minorVersion = Integer.valueOf(s);
                            if (tok.hasMoreTokens()) {

                                s = tok.nextToken();
                                try {
                                    this.incrementalVersion = Integer.valueOf(s);

                                } catch (NumberFormatException e) {
                                    this.qualifier = s;
                                }
                            }
                        } catch (NumberFormatException e) {
                            this.qualifier = s;
                        }
                    }
                } catch (NumberFormatException e) {
                    this.qualifier = s;
                }
            }

            if (tok.hasMoreTokens()) {
                StringBuffer qualifier = new StringBuffer(this.qualifier != null ? this.qualifier : "");
                qualifier.append(tok.nextToken());
                while (tok.hasMoreTokens()) {
                    qualifier.append("_");
                    qualifier.append(tok.nextToken());
                }

                this.qualifier = qualifier.toString();
            }

        }
    }

    @Override
    public String toString() {
        return this.unparsed;
    }
}