package com.jsql.model.injection.method;
   
   import com.jsql.model.InjectionModel;
   import com.jsql.model.exception.JSqlException;
   import com.jsql.model.exception.StoppedByUserSlidingException;
   import com.jsql.util.I18nUtil;
   import com.jsql.util.JsonUtil;
   import com.jsql.util.LogLevelUtil;
   import org.apache.commons.lang3.StringUtils;
  import org.apache.logging.log4j.LogManager;
  import org.apache.logging.log4j.Logger;
  import org.json.JSONException;
  
  import java.io.Serializable;
  import java.util.AbstractMap.SimpleEntry;
  import java.util.List;
  import java.util.regex.Pattern;
  
  public abstract class AbstractMethodInjection implements Serializable {
      
      /**
       * Log4j logger sent to view.
       */
      private static final Logger LOGGER = LogManager.getRootLogger();
      
      protected final InjectionModel injectionModel;
      
      protected AbstractMethodInjection(InjectionModel injectionModel) {
          this.injectionModel = injectionModel;
      }
      
      public abstract boolean isCheckingAllParam();
      public abstract String getParamsAsString();
      public abstract List<SimpleEntry<String, String>> getParams();
      public abstract String name();
      
      public boolean testParameters(boolean hasFoundInjection) throws JSqlException {
          if (!hasFoundInjection) {
              LOGGER.log(
                  LogLevelUtil.CONSOLE_DEFAULT,
                  "{} {} params...",
                  () -> I18nUtil.valueByKey("LOG_CHECKING"),
                  () -> this.name().toLowerCase()
              );
              return this.testParameters();
          }
          return true;
      }
  
      /**
       * Verify if injection works for specific Method using 3 modes: standard (last param), injection point
       * and full params injection. Special injections like JSON and SOAP are checked.
       * @return true if injection didn't fail
       * @throws JSqlException when no params integrity, process stopped by user, or injection failure
       */
      public boolean testParameters() throws JSqlException {
          var hasFoundInjection = false;
          
          // Injects URL, Request or Header params only if user tests every params
          // or method is selected by user.
          if (
              !this.injectionModel.getMediatorUtils().getPreferencesUtil().isCheckingAllParam()
              && this.injectionModel.getMediatorUtils().getConnectionUtil().getMethodInjection() != this
          ) {
              return false;
          }
          
          // Force injection method of model to current running method
          this.injectionModel.getMediatorUtils().getConnectionUtil().setMethodInjection(this);
          
          // Injection by injection point in params or in path
          if (
              this.getParamsAsString().contains(InjectionModel.STAR)
              || this.injectionModel.getMediatorUtils().getConnectionUtil().getUrlBase().contains(InjectionModel.STAR)
          ) {
              hasFoundInjection = this.checkParamWithStar();
          } else if (!this.isCheckingAllParam()) {
              hasFoundInjection = this.checkLastParam();
          } else {
              hasFoundInjection = this.checkAllParams();
          }
          return hasFoundInjection;
      }
  
      private boolean checkParamWithStar() throws JSqlException {
          SimpleEntry<String, String> parameterToInject = this.getParams().stream()
              .filter(entry -> entry.getValue().contains("*"))
              .findFirst()
              .orElse(null);
          return this.injectionModel.getMediatorStrategy().testStrategies(parameterToInject);
      }
  
      /**
       *  Default injection: last param tested only
       */
      private boolean checkLastParam() throws JSqlException {
          // Will check param value by user.
          // Notice options 'Inject each URL params' and 'inject JSON' must be checked both
          // for JSON injection of last param
         SimpleEntry<String, String> parameterToInject = this.getParams().stream()
             .reduce((a, b) -> b)
             .orElseThrow(() -> new JSqlException("Missing last parameter"));
         return this.injectionModel.getMediatorStrategy().testStrategies(parameterToInject);
     }
 
     /**
      * Injection of every params: isCheckingAllParam() == true.
      * Params are tested one by one in two loops:
      * - inner loop erases * from previous param
      * - outer loop adds * to current param
      */
     private boolean checkAllParams() throws StoppedByUserSlidingException {
         // This param will be marked by * if injection is found,
         // inner loop will erase mark * otherwise
         for (SimpleEntry<String, String> paramBase: this.getParams()) {
             // This param is the current tested one.
             // For JSON value attributes are traversed one by one to test every value.
             // For standard value mark * is simply added to the end of its value.
             for (SimpleEntry<String, String> paramStar: this.getParams()) {
                 if (paramStar == paramBase) {
                     try {
                         if (this.isParamInjectable(paramStar)) {
                             return true;
                         }
                     } catch (JSONException e) {
                         LOGGER.log(LogLevelUtil.CONSOLE_JAVA, e, e);
                     }
                 }
             }
         }
         return false;
     }
 
     private boolean isParamInjectable(SimpleEntry<String, String> paramStar) throws StoppedByUserSlidingException {
         boolean hasFoundInjection;
         
         // Will test if current value is a JSON entity
         Object jsonEntity = JsonUtil.getJson(paramStar.getValue());
         
         // Define a tree of JSON attributes with path as the key: root.a => value of a
         List<SimpleEntry<String, String>> attributesJson = JsonUtil.createEntries(jsonEntity, "root", null);
         
         // When option 'Inject JSON' is selected and there's a JSON entity to inject
         // then loop through each path to add * at the end of value and test each strategy.
         // Marks * are erased between each test.
         if (!attributesJson.isEmpty() && this.injectionModel.getMediatorUtils().getPreferencesUtil().isCheckingAllJsonParam()) {
             hasFoundInjection = this.injectionModel.getMediatorUtils().getJsonUtil().testJsonParam(this, paramStar);
         } else {
             hasFoundInjection = this.testJsonlessParam(paramStar);  // Standard non JSON injection
         }
         return hasFoundInjection;
     }
     
     public boolean testJsonlessParam(SimpleEntry<String, String> paramStar) throws StoppedByUserSlidingException {
         var hasFoundInjection = false;
 
         paramStar.setValue(paramStar.getValue() + InjectionModel.STAR);
         
         try {
             LOGGER.log(
                 LogLevelUtil.CONSOLE_INFORM,
                 "{} {} parameter {}={}",
                 () -> I18nUtil.valueByKey("LOG_CHECKING"),
                 this::name,
                 paramStar::getKey,
                 () -> paramStar.getValue().replace(InjectionModel.STAR, StringUtils.EMPTY)
             );
             
             // Test current standard value marked with * for injection
             // Keep original param
             hasFoundInjection = this.injectionModel.getMediatorStrategy().testStrategies(paramStar);
             
         } catch (StoppedByUserSlidingException e) { // Break all params processing in upper methods
             throw e;
         } catch (JSqlException e) {  // Injection failure
             LOGGER.log(
                 LogLevelUtil.CONSOLE_ERROR,
                 "No {} injection found for parameter {}={} ({})",
                 this.name(),
                 paramStar.getKey(),
                 paramStar.getValue().replaceAll("\\+.?$|\\" + InjectionModel.STAR, StringUtils.EMPTY),
                 e.getMessage()
             );
         } finally {
             if (!hasFoundInjection) {  // Erase * from JSON if failure
                 
                 // Erase * at the end of each params
                 this.getParams().forEach(e ->
                     e.setValue(
                         e.getValue().replaceAll(Pattern.quote(InjectionModel.STAR) +"$", StringUtils.EMPTY)
                     )
                 );
                 
                 // TODO It erases STAR from value => * can't be used in parameter
                 paramStar.setValue(paramStar.getValue().replace(InjectionModel.STAR, StringUtils.EMPTY));
             }
         }
         return hasFoundInjection;
     }
 }