package com.jsql.model.injection.strategy;
   
   import com.jsql.model.InjectionModel;
   import com.jsql.model.accessible.DataAccess;
   import com.jsql.model.bean.util.Interaction;
   import com.jsql.model.bean.util.Request;
   import com.jsql.model.injection.vendor.model.VendorYaml;
   import com.jsql.model.injection.vendor.model.yaml.Configuration;
   import com.jsql.model.suspendable.AbstractSuspendable;
  import com.jsql.util.I18nUtil;
  import com.jsql.util.LogLevelUtil;
  import com.jsql.util.StringUtil;
  import org.apache.logging.log4j.LogManager;
  import org.apache.logging.log4j.Logger;
  
  import java.util.regex.Matcher;
  import java.util.regex.Pattern;
  
  public class StrategyInjectionStack extends AbstractStrategy {
  
      /**
       * Log4j logger sent to view.
       */
      private static final Logger LOGGER = LogManager.getRootLogger();
  
      private String performanceLength = "0";
  
      public StrategyInjectionStack(InjectionModel injectionModel) {
          super(injectionModel);
      }
  
      @Override
      public void checkApplicability() {
          if (this.injectionModel.getMediatorUtils().getPreferencesUtil().isStrategyStackDisabled()) {
              LOGGER.log(LogLevelUtil.CONSOLE_INFORM, AbstractStrategy.FORMAT_SKIP_STRATEGY_DISABLED, this.getName());
              return;
          }
  
          // Reset applicability of new Vendor
          this.isApplicable = false;
          var strategyYaml = this.injectionModel.getMediatorVendor().getVendor().instance().getModelYaml().getStrategy();
          var configurationYaml = strategyYaml.getConfiguration();
  
          this.logChecking();
  
          boolean methodIsApplicable = this.isApplicable(configurationYaml, strategyYaml.getStack());
          if (methodIsApplicable) {
              Matcher regexSearch = this.getPerformance(configurationYaml, strategyYaml.getStack());
              if (!regexSearch.find()) {
                  LOGGER.log(
                      LogLevelUtil.CONSOLE_ERROR,
                      "{} {} but injectable size is incorrect",
                      () -> I18nUtil.valueByKey("LOG_VULNERABLE"),
                      () -> "Stack"
                  );
                  methodIsApplicable = false;
              } else {
                  this.performanceLength = String.valueOf(regexSearch.group(1).length());
              }
          }
  
          if (methodIsApplicable) {
              LOGGER.log(
                  LogLevelUtil.CONSOLE_SUCCESS,
                  "{} Stack injection showing [{}] characters",
                  () -> I18nUtil.valueByKey("LOG_VULNERABLE"),
                  () -> this.performanceLength
              );
              this.allow();
          } else {
              this.unallow();
          }
      }
  
      private boolean isApplicable(Configuration configurationYaml, String stack) {
          var methodIsApplicable = false;
          var indexZeroToFind = "0";
          String performanceSourcePage = this.injectionModel.injectWithoutIndex(
              VendorYaml.replaceTags(
                  stack
                  .replace(VendorYaml.WINDOW, configurationYaml.getSlidingWindow())
                  .replace(VendorYaml.INJECTION, configurationYaml.getFailsafe().replace(VendorYaml.INDICE,indexZeroToFind))
                  .replace(VendorYaml.WINDOW_CHAR, "1")
                  .replace(VendorYaml.CAPACITY, VendorYaml.DEFAULT_CAPACITY)
              ),
              "stack#confirm"
          );
          String regexIndexZero = String.format(VendorYaml.FORMAT_INDEX, indexZeroToFind);
          if (performanceSourcePage.matches("(?s).*"+ regexIndexZero +".*")) {
              methodIsApplicable = true;
              this.isApplicable = true;
          }
          return methodIsApplicable;
      }
  
      private Matcher getPerformance(Configuration configurationYaml, String stack) {
          String performanceSourcePage = this.injectionModel.injectWithoutIndex(
              VendorYaml.replaceTags(
                  stack
                 .replace(VendorYaml.WINDOW, configurationYaml.getSlidingWindow())
                 .replace(VendorYaml.INJECTION, configurationYaml.getCalibrator())
                 .replace(VendorYaml.WINDOW_CHAR, "1")
                 .replace(VendorYaml.CAPACITY, VendorYaml.DEFAULT_CAPACITY)
             ),
             "stack#size"
         );
         return Pattern.compile("(?s)"+ DataAccess.LEAD +"("+ VendorYaml.CALIBRATOR_SQL +"+)").matcher(performanceSourcePage);
     }
 
     @Override
     public void allow(int... i) {
         this.injectionModel.appendAnalysisReport(
             StringUtil.formatReport(LogLevelUtil.COLOR_BLU, "### Strategy: " + this.getName())
             + this.injectionModel.getReportWithoutIndex(
                 this.injectionModel.getMediatorVendor().getVendor().instance().sqlStack(StringUtil.formatReport(LogLevelUtil.COLOR_GREEN, "<query>"), "0", true),
                 "metadataInjectionProcess"
             )
         );
         this.markVulnerability(Interaction.MARK_STACK_VULNERABLE);
     }
 
     @Override
     public void unallow(int... i) {
         this.markVulnerability(Interaction.MARK_STACK_INVULNERABLE);
     }
 
     @Override
     public String inject(String sqlQuery, String startPosition, AbstractSuspendable stoppable, String metadataInjectionProcess) {
         return this.injectionModel.injectWithoutIndex(
             this.injectionModel.getMediatorVendor().getVendor().instance().sqlStack(sqlQuery, startPosition, false),
             metadataInjectionProcess
         );
     }
 
     @Override
     public void activateWhenApplicable() {
         if (this.injectionModel.getMediatorStrategy().getStrategy() == null && this.isApplicable()) {
             LOGGER.log(
                 LogLevelUtil.CONSOLE_INFORM,
                 "{} [{}]",
                 () -> I18nUtil.valueByKey("LOG_USING_STRATEGY"),
                 this::getName
             );
             this.injectionModel.getMediatorStrategy().setStrategy(this.injectionModel.getMediatorStrategy().getStack());
 
             var request = new Request();
             request.setMessage(Interaction.MARK_STACK_STRATEGY);
             this.injectionModel.sendToViews(request);
         }
     }
 
     @Override
     public String getPerformanceLength() {
         return this.performanceLength;
     }
 
     @Override
     public String getName() {
         return "Stack";
     }
 }