/*
    * This file is part of dependency-check-core.
    *
    * 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.
   *
   * Copyright (c) 2013 Jeremy Long. All Rights Reserved.
   */
  package org.owasp.dependencycheck.xml.suppression;
  
  import java.util.ArrayList;
  import java.util.Calendar;
  import java.util.HashSet;
  import java.util.Iterator;
  import java.util.List;
  import java.util.Set;
  import javax.annotation.concurrent.NotThreadSafe;
  import org.apache.commons.lang3.time.DateFormatUtils;
  import org.owasp.dependencycheck.dependency.Dependency;
  import org.owasp.dependencycheck.dependency.Vulnerability;
  import org.owasp.dependencycheck.dependency.naming.CpeIdentifier;
  import org.owasp.dependencycheck.dependency.naming.Identifier;
  import org.owasp.dependencycheck.dependency.naming.PurlIdentifier;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  import us.springett.parsers.cpe.Cpe;
  import us.springett.parsers.cpe.exceptions.CpeEncodingException;
  
  /**
   *
   * @author Jeremy Long
   */
  @NotThreadSafe
  public class SuppressionRule {
  
      /**
       * The Logger for use throughout the class.
       */
      private static final Logger LOGGER = LoggerFactory.getLogger(SuppressionRule.class);
      /**
       * The file path for the suppression.
       */
      private PropertyType filePath;
  
      /**
       * The SHA1 hash.
       */
      private String sha1;
      /**
       * A list of CPEs to suppression
       */
      private List<PropertyType> cpe = new ArrayList<>();
      /**
       * The list of cvssBelow scores.
       */
      private List<Double> cvssBelow = new ArrayList<>();
      /**
       * The list of CWE entries to suppress.
       */
      private List<String> cwe = new ArrayList<>();
      /**
       * The list of CVE entries to suppress.
       */
      private List<String> cve = new ArrayList<>();
      /**
       * The list of vulnerability name entries to suppress.
       */
      private final List<PropertyType> vulnerabilityNames = new ArrayList<>();
      /**
       * A Maven GAV to suppression.
       */
      private PropertyType gav = null;
      /**
       * The list of vulnerability name entries to suppress.
       */
      private PropertyType packageUrl = null;
      /**
       * The notes added in suppression file
       */
  
      private String notes;
  
      /**
       * A flag indicating whether or not the suppression rule is a core/base rule
       * that should not be included in the resulting report in the "suppressed"
       * section.
       */
      private boolean base;
  
      /**
      * A date until which the suppression is to be retained. This can be used to
      * make a temporary suppression that auto-expires to suppress a CVE while
      * waiting for the vulnerability fix of the dependency to be released.
      */
     private Calendar until;
 
     /**
      * A flag whether or not the rule matched a dependency & CPE.
      */
     private boolean matched = false;
 
     /**
      * Get the value of matched.
      *
      * @return the value of matched
      */
     public boolean isMatched() {
         return matched;
     }
 
     /**
      * Set the value of matched.
      *
      * @param matched new value of matched
      */
     public void setMatched(boolean matched) {
         this.matched = matched;
     }
 
     /**
      * Get the (@code{nullable}) value of until.
      *
      * @return the value of until
      */
     public Calendar getUntil() {
         return until;
     }
 
     /**
      * Set the value of until.
      *
      * @param until new value of until
      */
     public void setUntil(Calendar until) {
         this.until = until;
     }
 
     /**
      * Get the value of filePath.
      *
      * @return the value of filePath
      */
     public PropertyType getFilePath() {
         return filePath;
     }
 
     /**
      * Set the value of filePath.
      *
      * @param filePath new value of filePath
      */
     public void setFilePath(PropertyType filePath) {
         this.filePath = filePath;
     }
 
     /**
      * Get the value of sha1.
      *
      * @return the value of sha1
      */
     public String getSha1() {
         return sha1;
     }
 
     /**
      * Set the value of SHA1.
      *
      * @param sha1 new value of SHA1
      */
     public void setSha1(String sha1) {
         this.sha1 = sha1;
     }
 
     /**
      * Get the value of CPE.
      *
      * @return the value of CPE
      */
     public List<PropertyType> getCpe() {
         return cpe;
     }
 
     /**
      * Set the value of CPE.
      *
      * @param cpe new value of CPE
      */
     public void setCpe(List<PropertyType> cpe) {
         this.cpe = cpe;
     }
 
     /**
      * Adds the CPE to the CPE list.
      *
      * @param cpe the CPE to add
      */
     public void addCpe(PropertyType cpe) {
         this.cpe.add(cpe);
     }
 
     /**
      * Adds the CPE to the CPE list.
      *
      * @param name the vulnerability name to add
      */
     public void addVulnerabilityName(PropertyType name) {
         this.vulnerabilityNames.add(name);
     }
 
     /**
      * Returns whether or not this suppression rule as CPE entries.
      *
      * @return whether or not this suppression rule as CPE entries
      */
     public boolean hasCpe() {
         return !cpe.isEmpty();
     }
 
     /**
      * Get the value of cvssBelow.
      *
      * @return the value of cvssBelow
      */
     public List<Double> getCvssBelow() {
         return cvssBelow;
     }
 
     /**
      * Set the value of cvssBelow.
      *
      * @param cvssBelow new value of cvssBelow
      */
     public void setCvssBelow(List<Double> cvssBelow) {
         this.cvssBelow = cvssBelow;
     }
 
     /**
      * Adds the CVSS to the cvssBelow list.
      *
      * @param cvss the CVSS to add
      */
     public void addCvssBelow(Double cvss) {
         this.cvssBelow.add(cvss);
     }
 
     /**
      * Returns whether or not this suppression rule has CVSS suppression criteria.
      *
      * @return whether or not this suppression rule has CVSS suppression criteria.
      */
     public boolean hasCvssBelow() {
         return !cvssBelow.isEmpty();
     }
 
     /**
      * Get the value of notes.
      *
      * @return the value of notes
      */
     public String getNotes() {
         return notes;
     }
 
     /**
      * Set the value of notes.
      *
      * @param notes new value of notes
      */
     public void setNotes(String notes) {
         this.notes = notes;
     }
 
     /**
      * Returns whether this suppression rule has notes entries.
      *
      * @return whether this suppression rule has notes entries
      */
     public boolean hasNotes() {
         return !notes.isEmpty();
     }
 
     /**
      * Get the value of CWE.
      *
      * @return the value of CWE
      */
     public List<String> getCwe() {
         return cwe;
     }
 
     /**
      * Set the value of CWE.
      *
      * @param cwe new value of CWE
      */
     public void setCwe(List<String> cwe) {
         this.cwe = cwe;
     }
 
     /**
      * Adds the CWE to the CWE list.
      *
      * @param cwe the CWE to add
      */
     public void addCwe(String cwe) {
         this.cwe.add(cwe);
     }
 
     /**
      * Returns whether this suppression rule has CWE entries.
      *
      * @return whether this suppression rule has CWE entries
      */
     public boolean hasCwe() {
         return !cwe.isEmpty();
     }
 
     /**
      * Get the value of CVE.
      *
      * @return the value of CVE
      */
     public List<String> getCve() {
         return cve;
     }
 
     /**
      * Set the value of CVE.
      *
      * @param cve new value of CVE
      */
     public void setCve(List<String> cve) {
         this.cve = cve;
     }
 
     /**
      * Adds the CVE to the CVE list.
      *
      * @param cve the CVE to add
      */
     public void addCve(String cve) {
         this.cve.add(cve);
     }
 
     /**
      * Returns whether this suppression rule has CVE entries.
      *
      * @return whether this suppression rule has CVE entries
      */
     public boolean hasCve() {
         return !cve.isEmpty();
     }
 
     /**
      * Returns whether this suppression rule has vulnerabilityName entries.
      *
      * @return whether this suppression rule has vulnerabilityName entries
      */
     public boolean hasVulnerabilityName() {
         return !vulnerabilityNames.isEmpty();
     }
 
     /**
      * Get the value of Maven GAV.
      *
      * @return the value of GAV
      */
     public PropertyType getGav() {
         return gav;
     }
 
     /**
      * Set the value of Maven GAV.
      *
      * @param gav new value of Maven GAV
      */
     public void setGav(PropertyType gav) {
         this.gav = gav;
     }
 
     /**
      * Returns whether or not this suppression rule as GAV entries.
      *
      * @return whether or not this suppression rule as GAV entries
      */
     public boolean hasGav() {
         return gav != null;
     }
 
     /**
      * Set the value of Package URL.
      *
      * @param purl new value of package URL
      */
     public void setPackageUrl(PropertyType purl) {
         this.packageUrl = purl;
     }
 
     /**
      * Returns whether or not this suppression rule as packageUrl entries.
      *
      * @return whether or not this suppression rule as packageUrl entries
      */
     public boolean hasPackageUrl() {
         return packageUrl != null;
     }
 
     /**
      * Get the value of base.
      *
      * @return the value of base
      */
     public boolean isBase() {
         return base;
     }
 
     /**
      * Set the value of base.
      *
      * @param base new value of base
      */
     public void setBase(boolean base) {
         this.base = base;
     }
 
     /**
      * Processes a given dependency to determine if any CPE, CVE, CWE, or CVSS
      * scores should be suppressed. If any should be, they are removed from the
      * dependency.
      *
      * @param dependency a project dependency to analyze
      */
     public void process(Dependency dependency) {
         if (filePath != null && !filePath.matches(dependency.getFilePath())) {
             return;
         }
         if (sha1 != null && !sha1.equalsIgnoreCase(dependency.getSha1sum())) {
             return;
         }
         if (hasGav()) {
             final Iterator<Identifier> itr = dependency.getSoftwareIdentifiers().iterator();
             boolean found = false;
             while (itr.hasNext()) {
                 final Identifier i = itr.next();
                 if (identifierMatches(this.gav, i)) {
                     found = true;
                     break;
                 }
             }
             if (!found) {
                 return;
             }
         }
         if (hasPackageUrl()) {
             final Iterator<Identifier> itr = dependency.getSoftwareIdentifiers().iterator();
             boolean found = false;
             while (itr.hasNext()) {
                 final Identifier i = itr.next();
                 if (purlMatches(this.packageUrl, i)) {
                     found = true;
                     break;
                 }
             }
             if (!found) {
                 return;
             }
         }
 
         if (this.hasCpe()) {
             final Set<Identifier> removalList = new HashSet<>();
             for (Identifier i : dependency.getVulnerableSoftwareIdentifiers()) {
                 for (PropertyType c : this.cpe) {
                     if (identifierMatches(c, i)) {
                         if (!isBase()) {
                             matched = true;
                             if (this.notes != null) {
                                 i.setNotes(this.notes);
                             }
                             dependency.addSuppressedIdentifier(i);
                         }
                         removalList.add(i);
                         break;
                     }
                 }
             }
             removalList.forEach(dependency::removeVulnerableSoftwareIdentifier);
         }
         if (hasCve() || hasVulnerabilityName() || hasCwe() || hasCvssBelow()) {
             final Set<Vulnerability> removeVulns = new HashSet<>();
             for (Vulnerability v : dependency.getVulnerabilities()) {
                 boolean remove = false;
                 for (String entry : this.cve) {
                     if (entry.equalsIgnoreCase(v.getName())) {
                         removeVulns.add(v);
                         remove = true;
                         break;
                     }
                 }
                 if (!remove && this.cwe != null && !v.getCwes().isEmpty()) {
                     for (String entry : this.cwe) {
                         final String toMatch = String.format("CWE-%s", entry);
                         if (v.getCwes().stream().anyMatch(toTest -> toMatch.regionMatches(0, toTest, 0, toMatch.length()))) {
                             remove = true;
                             removeVulns.add(v);
                             break;
                         }
                     }
                 }
                 if (!remove && v.getName() != null) {
                     for (PropertyType entry : this.vulnerabilityNames) {
                         if (entry.matches(v.getName())) {
                             remove = true;
                             removeVulns.add(v);
                             break;
                         }
                     }
                 }
                 if (!remove) {
                     for (Double cvss : this.cvssBelow) {
                         //TODO validate this comparison
                         if (v.getCvssV2() != null && v.getCvssV2().getCvssData().getBaseScore().compareTo(cvss) < 0) {
                             remove = true;
                             removeVulns.add(v);
                             break;
                         }
                         if (v.getCvssV3() != null && v.getCvssV3().getCvssData().getBaseScore().compareTo(cvss) < 0) {
                             remove = true;
                             removeVulns.add(v);
                             break;
                         }
                     }
                 }
                 if (remove && !isBase()) {
                     matched = true;
                     if (this.notes != null) {
                         v.setNotes(this.notes);
                     }
                     dependency.addSuppressedVulnerability(v);
                 }
             }
             removeVulns.forEach(dependency::removeVulnerability);
         }
     }
 
     /**
      * Identifies if the cpe specified by the cpe suppression rule does not
      * specify a version.
      *
      * @param c a suppression rule identifier
      * @return true if the property type does not specify a version; otherwise
      * false
      */
     protected boolean cpeHasNoVersion(PropertyType c) {
         return !c.isRegex() && countCharacter(c.getValue(), ':') <= 3;
     }
 
     /**
      * Counts the number of occurrences of the character found within the
      * string.
      *
      * @param str the string to check
      * @param c the character to count
      * @return the number of times the character is found in the string
      */
     private int countCharacter(String str, char c) {
         int count = 0;
         int pos = str.indexOf(c) + 1;
         while (pos > 0) {
             count += 1;
             pos = str.indexOf(c, pos) + 1;
         }
         return count;
     }
 
     /**
      * Determines if the cpeEntry specified as a PropertyType matches the given
      * Identifier.
      *
      * @param suppressionEntry a suppression rule entry
      * @param identifier a CPE identifier to check
      * @return true if the entry matches; otherwise false
      */
     protected boolean purlMatches(PropertyType suppressionEntry, Identifier identifier) {
         if (identifier instanceof PurlIdentifier) {
             final PurlIdentifier purl = (PurlIdentifier) identifier;
             return suppressionEntry.matches(purl.toString());
         }
         return false;
     }
 
     /**
      * Determines if the cpeEntry specified as a PropertyType matches the given
      * Identifier.
      *
      * @param suppressionEntry a suppression rule entry
      * @param identifier a CPE identifier to check
      * @return true if the entry matches; otherwise false
      */
     protected boolean identifierMatches(PropertyType suppressionEntry, Identifier identifier) {
         if (identifier instanceof PurlIdentifier) {
             final PurlIdentifier purl = (PurlIdentifier) identifier;
             return suppressionEntry.matches(purl.toGav());
         } else if (identifier instanceof CpeIdentifier) {
             //TODO check for regex - not just type
             final Cpe cpeId = ((CpeIdentifier) identifier).getCpe();
             if (suppressionEntry.isRegex()) {
                 try {
                     return suppressionEntry.matches(cpeId.toCpe22Uri());
                 } catch (CpeEncodingException ex) {
                     LOGGER.debug("Unable to convert CPE to 22 URI?" + cpeId);
                 }
             } else if (suppressionEntry.isCaseSensitive()) {
                 try {
                     return cpeId.toCpe22Uri().startsWith(suppressionEntry.getValue());
                 } catch (CpeEncodingException ex) {
                     LOGGER.debug("Unable to convert CPE to 22 URI?" + cpeId);
                 }
             } else {
                 final String id;
                 try {
                     id = cpeId.toCpe22Uri().toLowerCase();
                 } catch (CpeEncodingException ex) {
                     LOGGER.debug("Unable to convert CPE to 22 URI?" + cpeId);
                     return false;
                 }
                 final String check = suppressionEntry.getValue().toLowerCase();
                 return id.startsWith(check);
             }
         }
         return suppressionEntry.matches(identifier.getValue());
     }
 
     /**
      * Standard toString implementation.
      *
      * @return a string representation of this object
      */
     @Override
     public String toString() {
         final StringBuilder sb = new StringBuilder(64);
         sb.append("SuppressionRule{");
         if (until != null) {
             final String dt = DateFormatUtils.ISO_8601_EXTENDED_DATETIME_TIME_ZONE_FORMAT.format(until);
             sb.append("until=").append(dt).append(',');
         }
         if (filePath != null) {
             sb.append("filePath=").append(filePath).append(',');
         }
         if (sha1 != null) {
             sb.append("sha1=").append(sha1).append(',');
         }
         if (packageUrl != null) {
             sb.append("packageUrl=").append(packageUrl).append(',');
         }
         if (gav != null) {
             sb.append("gav=").append(gav).append(',');
         }
         if (cpe != null && !cpe.isEmpty()) {
             sb.append("cpe={");
             cpe.forEach((pt) -> sb.append(pt).append(','));
             sb.append('}');
         }
         if (cwe != null && !cwe.isEmpty()) {
             sb.append("cwe={");
             cwe.forEach((s) -> sb.append(s).append(','));
             sb.append('}');
         }
         if (cve != null && !cve.isEmpty()) {
             sb.append("cve={");
             cve.forEach((s) -> sb.append(s).append(','));
             sb.append('}');
         }
         if (vulnerabilityNames != null && !vulnerabilityNames.isEmpty()) {
             sb.append("vulnerabilityName={");
             vulnerabilityNames.forEach((pt) -> sb.append(pt).append(','));
             sb.append('}');
         }
         if (cvssBelow != null && !cvssBelow.isEmpty()) {
             sb.append("cvssBelow={");
             cvssBelow.forEach((s) -> sb.append(s).append(','));
             sb.append('}');
         }
         sb.append('}');
         return sb.toString();
     }
 }