package org.hl7.fhir.r5.model;

/*
  Copyright (c) 2011+, HL7, Inc.
  All rights reserved.
  
  Redistribution and use in source and binary forms, with or without modification, \
  are permitted provided that the following conditions are met:
  
   * Redistributions of source code must retain the above copyright notice, this \
     list of conditions and the following disclaimer.
   * Redistributions in binary form must reproduce the above copyright notice, \
     this list of conditions and the following disclaimer in the documentation \
     and/or other materials provided with the distribution.
   * Neither the name of HL7 nor the names of its contributors may be used to 
     endorse or promote products derived from this software without specific 
     prior written permission.
  
  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS \"AS IS\" AND \
  ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED \
  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. \
  IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, \
  INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT \
  NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR \
  PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, \
  WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) \
  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE \
  POSSIBILITY OF SUCH DAMAGE.
  */

import java.io.Serializable;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.hl7.fhir.exceptions.FHIRException;
import org.hl7.fhir.instance.model.api.IBase;
import org.hl7.fhir.r5.fhirpath.FHIRPathEngine;
import org.hl7.fhir.utilities.FhirPublication;
import org.hl7.fhir.utilities.Utilities;
import org.hl7.fhir.utilities.validation.ValidationMessage;
import org.hl7.fhir.utilities.xhtml.XhtmlNode;

import ca.uhn.fhir.model.api.IElement;

public abstract class Base implements Serializable, IBase, IElement {

  public enum ValidationReason {
    Validation, MatchingSlice, Expression    
  }
  
  public enum ProfileSource {
    BaseDefinition, ConfigProfile, MetaProfile, ProfileDependency, FromExpression,  GlobalProfile
  }
  
  public static class ValidationMode {
    private ValidationReason reason;
    private ProfileSource source;
    public ValidationMode(ValidationReason reason, ProfileSource source) {
      super();
      this.reason = reason;
      this.source = source;
    }
    public ValidationReason getReason() {
      return reason;
    }
    public ProfileSource getSource() {
      return source;
    }
    public ValidationMode withSource(ProfileSource source) {
      ValidationMode res = new ValidationMode(reason, source);
      return res;
    }
    public ValidationMode withReason(ValidationReason reason) {
      ValidationMode res = new ValidationMode(reason, source);
      return res;
    }
  }
  
  public class ValidationInfo {
    private StructureDefinition structure;
    private ElementDefinition definition;
    private ValidationReason reason;
    private ProfileSource source;
    private boolean valid;
    
    public ValidationInfo(StructureDefinition structure, ElementDefinition definition, ValidationMode mode) {
      super();
      this.structure = structure;
      this.definition = definition;
      this.reason = mode.reason;
      this.source = mode.source;
    }
    
    public StructureDefinition getStructure() {
      return structure;
    }
    
    public ElementDefinition getDefinition() {
      return definition;
    }
    
    public ValidationReason getReason() {
      return reason;
    }

    public ProfileSource getSource() {
      return source;
    }

    public boolean isValid() {
      return valid;
    }
    public void setValid(boolean valid) {
      this.valid = valid;
    }

  }

  private static ThreadLocal<Boolean> copyUserData = new ThreadLocal<>();
  
  public static boolean isCopyUserData() {
    Boolean res = copyUserData.get();
    return res != null && res;
  }
  
  public static void setCopyUserData(boolean value) {
    copyUserData.set(value);
  }
  
  /**
   * User appended data items - allow users to add extra information to the class
   */
  private transient Map<String, Object> userData; 

  /**
   * Post Validation Definition information
   */
  private transient List<ValidationInfo> validationInfo;

  /**
   * Round tracking xml comments for testing convenience
   */
  private List<String> formatCommentsPre; 
   
  /**
   * Round tracking xml comments for testing convenience
   */
  private List<String> formatCommentsPost;

  private List<ValidationMessage> validationMessages; 
   
  
  public Object getUserData(String name) {
    if (userData == null)
      return null;
    return userData.get(name);
  }
  
  public void setUserData(String name, Object value) {
    if (userData == null)
      userData = new HashMap<String, Object>();
    userData.put(name, value);
  }

  public void clearUserData(String name) {
    if (userData != null)
      userData.remove(name);
  }
 
  
  public void setUserDataINN(String name, Object value) {
    if (value == null)
      return;
    
    if (userData == null)
      userData = new HashMap<String, Object>();
    userData.put(name, value);
  }

  public boolean hasUserData(String name) {
    if (userData == null)
      return false;
    else
      return userData.containsKey(name) && (userData.get(name) != null);
  }

        public String getUserString(String name) {
    Object ud = getUserData(name);
    if (ud == null)
      return null;
    if (ud instanceof String)
      return (String) ud;
    return ud.toString();
  }

  public int getUserInt(String name) {
    if (!hasUserData(name))
      return 0;
    return (Integer) getUserData(name);
  }

  public void copyUserData(Base other) {
    if (other.userData != null) {
      if (userData == null) {
        userData = new HashMap<>();
      }
      userData.putAll(other.userData);
    }
  }      

  public boolean hasFormatComment() {
    return hasFormatCommentPre() || hasFormatCommentPost();
  }
  
  public boolean hasFormatCommentPre() {
    return formatCommentsPre != null && !formatCommentsPre.isEmpty();
  }
  
  public boolean hasFormatCommentPost() {
    return formatCommentsPost != null && !formatCommentsPost.isEmpty();
  }
  
  public List<String> getFormatCommentsPre() {
    if (formatCommentsPre == null)
      formatCommentsPre = new ArrayList<String>();
    return formatCommentsPre;
  }
  
  public List<String> getFormatCommentsPost() {
    if (formatCommentsPost == null)
      formatCommentsPost = new ArrayList<String>();
    return formatCommentsPost;
  }  
  

  public void copyFormatComments(Base other) {
    if (other.hasFormatComment()) {
      formatCommentsPre = new ArrayList<>();
      formatCommentsPre.addAll(other.formatCommentsPre);      
    } else {
      formatCommentsPre = null;
    }
  }
  

  public void addFormatCommentsPre(List<String> comments) {
    if (comments != null && !comments.isEmpty()) {
      getFormatCommentsPre().addAll(comments); 
    }    
  }

  public void addFormatCommentsPost(List<String> comments) {
    if (comments != null && !comments.isEmpty()) {
      getFormatCommentsPost().addAll(comments); 
    }    
  }

        // these 3 allow evaluation engines to get access to primitive values
  
  /**
   * @return true if the data type is a primitive type and might have a primitive value 
   *   (which will be accessed as a string, irrespective of the stated value)
   */
        public boolean isPrimitive() {
                return false;
        }
        
        /**
         * @return true if the type is boolean, and the primitive value can only be 'true' or 'false'
         */
  public boolean isBooleanPrimitive() {
    return false;
  }

  /**
   * @return true if the type is primitive, and there's value (e.g. no Data-Absent-Reason extension etc)
   */
  public boolean hasPrimitiveValue() {
    return primitiveValue() != null;
  }
  
  /**
   * @return true if the type is primitive, and there could be a value (irrespective of whether it's present e.g. no Data-Absent-Reason extension etc)
   */
  public boolean canHavePrimitiveValue() {
    return false;
  }
  
        /**
         * @return the primitive value if there is one, as a string irrespective of the actual type (e.g. dates converted to their FHIR string representation)
         *    return null if the value is not a primitive or there is no value (might be extensions instead)
         */
        public String primitiveValue() {
                return null;
        }
        
  /**
   * @return true if the type is date|dateTime|instant, and the primitive value is a date/time of some precision
   */
  public boolean isDateTime() {
    return false;
  }

  /**
   * @return the date/time value if there is one, or null
   */
  public BaseDateTimeType dateTimeValue() {
    return null;
  }

  /**
   * @return the FHIR type name of the instance (not the java class name)
   */
        public abstract String fhirType() ;

        /**
         * Note that this is potentially misleading on ElementDefinition that has a 'type' 
         * property - don't mistakenly use this thinking it's going to look at ElementDefinition.type
   *
         * @param name - fhir type name
         * @return- true if it 'has' this type (including by specialization)
         */
        public boolean hasType(String... name) {
                String t = fhirType();
                for (String n : name) {
                  if (n.equalsIgnoreCase(t))
                        return true;
                  if (n.contains(".")) {
                    String[] p = n.split("\\.");
                    if (p.length == 2 && Utilities.existsInList(p[0], "FHIR", "CDA") && p[1].equalsIgnoreCase(t))
                return true;
                  }
                }
                return false;
        }
        
        protected void listChildren(List<Property> result) {
          // nothing
        }
        
        public Base setProperty(String name, Base value) throws FHIRException {
          throw new FHIRException("Attempt to set unknown property "+name);
        }
        
        public Base addChild(String name) throws FHIRException {
    throw new FHIRException("Attempt to add child with unknown name "+name);
  }

        public void removeChild(String name, Base value) throws FHIRException {
    throw new FHIRException("Attempt to remove child with unknown name "+name);
        }
  /**
   * Supports iterating the children elements in some generic processor or browser
   * All defined children will be listed, even if they have no value on this instance
   * 
   * Note that the actual content of primitive or xhtml elements is not iterated explicitly.
   * To find these, the processing code must recognise the element as a primitive, typecast
   * the value to a {@link DataType}, and examine the value
   *  
   * @return a list of all the children defined for this element
   */
  public List<Property> children() {
        List<Property> result = new ArrayList<Property>();
        listChildren(result);
        return result;
  }

  public Property getChildByName(String name) {
    List<Property> children = new ArrayList<Property>();
    listChildren(children);
    for (Property c : children)
      if (c.getName().equals(name) || c.getName().equals(name+"[x]")) {
        return c;
      }
      return null;
    }
  
  public List<Base> listChildrenByName(String name) throws FHIRException {
    List<Base> result = new ArrayList<Base>();
        for (Base b : listChildrenByName(name, true))
                if (b != null)
                  result.add(b);
    return result;
  }

  public Base getChildValueByName(String name) {
    Property p = getChildByName(name);
    if (p != null && p.hasValues()) {
      if (p.getValues().size() > 1) {
        throw new Error("Too manye values for "+name+" found");
      } else {
        return p.getValues().get(0);        
      }
    }
    return null;
  }
  
  public Base[] listChildrenByName(String name, boolean checkValid) throws FHIRException {
        if (name.equals("*")) {
                List<Property> children = new ArrayList<Property>();
                listChildren(children);
                List<Base> result = new ArrayList<Base>();
                for (Property c : children)
                                result.addAll(c.getValues());
                return result.toArray(new Base[result.size()]);
        }
        else
        return getProperty(name.hashCode(), name, checkValid);
  }

        public boolean isEmpty() {
          return true; // userData does not count
  }

        public boolean equalsDeep(Base other) {
          return other != null;
  }  
  
        public boolean equalsShallow(Base other) {
          return other != null;
  }  
  
  public static boolean compareDeep(String s1, String s2, boolean allowNull) {
    if (allowNull) {
      boolean noLeft = s1 == null || Utilities.noString(s1);
      boolean noRight = s2 == null || Utilities.noString(s2);
      if (noLeft && noRight) {
        return true;
      }
    }
    if (s1 == null || s2 == null)
      return false;
    return s1.equals(s2);   
  }
  
        public static boolean compareDeep(List<? extends Base> e1, List<? extends Base> e2, boolean allowNull) {
                if (noList(e1) && noList(e2) && allowNull)
                        return true;
                if (noList(e1) || noList(e2))
                        return false;
                if (e1.size() != e2.size())
                        return false;
                for (int i = 0; i < e1.size(); i++) {
                        if (!compareDeep(e1.get(i), e2.get(i), allowNull))
                                return false;
                }
                return true;
        }
        
        private static boolean noList(List<? extends Base> list) {
    return list == null || list.isEmpty() || (list.size() == 1 && list.get(0).isEmpty());
  }

        public static boolean compareDeep(Base e1, Base e2, boolean allowNull) {
                if (allowNull) {
                        boolean noLeft = e1 == null || e1.isEmpty();
                        boolean noRight = e2 == null || e2.isEmpty();
                        if (noLeft && noRight) {
                        return true;
                        }
                }
                if (e1 == null || e2 == null)
                        return false;
                if (e2.isMetadataBased() && !e1.isMetadataBased()) // respect existing order for debugging consistency; outcome must be the same either way
                        return e2.equalsDeep(e1);
                else
                return e1.equalsDeep(e2);
        }
        
        public static boolean compareDeep(XhtmlNode div1, XhtmlNode div2, boolean allowNull) {
                if (div1 == null && div2 == null && allowNull)
                        return true;
                if (div1 == null || div2 == null)
                        return false;
                return div1.equalsDeep(div2);
  }


        public static boolean compareValues(List<? extends PrimitiveType> e1, List<? extends PrimitiveType> e2, boolean allowNull) {
                if (e1 == null && e2 == null && allowNull)
                        return true;
                if (e1 == null || e2 == null)
                        return false;
                if (e1.size() != e2.size())
                        return false;
                for (int i = 0; i < e1.size(); i++) {
                        if (!compareValues(e1.get(i), e2.get(i), allowNull))
                                return false;
                }
                return true;
        }

        public static boolean compareValues(PrimitiveType e1, PrimitiveType e2, boolean allowNull) {
                boolean noLeft = e1 == null || e1.isEmpty();
                boolean noRight = e2 == null || e2.isEmpty();
      if (noLeft && noRight && allowNull) {
                        return true;
      }
                if (noLeft != noRight)
                        return false;
                return e1.equalsShallow(e2);
  }
        
        protected boolean isMetadataBased() {
        return false;
        }

        public Base[] getProperty(int hash, String name, boolean checkValid) throws FHIRException {
                if (checkValid)
                        throw new FHIRException("Attempt to read invalid property '"+name+"' on type "+fhirType());
        return null; 
        }

        public Base setProperty(int hash, String name, Base value) throws FHIRException {
                throw new FHIRException("Attempt to write to invalid property '"+name+"' on type "+fhirType());
        }

        public Base makeProperty(int hash, String name) throws FHIRException {
                throw new FHIRException("Attempt to make an invalid property '"+name+"' on type "+fhirType());
        }

        public String[] getTypesForProperty(int hash, String name) throws FHIRException {
    throw new FHIRException("Attempt to get types for an invalid property '"+name+"' on type "+fhirType());
        }
        
        public static boolean equals(String v1, String v2) {
        if (v1 == null && v2 == null)
                return true;
        else if (v1 == null || v2 == null)
        return false;
        else
                return v1.equals(v2);
        }

  public boolean isResource() {
    return false;
  }
        

  public abstract String getIdBase();
  public abstract void setIdBase(String value);

  public Property getNamedProperty(String _name) throws FHIRException {
    return getNamedProperty(_name.hashCode(), _name, false);
  }
  public Property getNamedProperty(int _hash, String _name, boolean _checkValid) throws FHIRException {
    if (_checkValid)
      throw new FHIRException("Attempt to read invalid property '"+_name+"' on type "+fhirType());
    return null; 
  }

  public abstract Base copy();
  
  public void copyValues(Base dst) {  
    if (isCopyUserData() && userData != null) {
      dst.userData = new HashMap<>();
      dst.userData.putAll(userData);
    }
  }

  /**
   * return XHTML if this is an XHTML node, else null
   * 
   * @return
   */
  public XhtmlNode getXhtml() {
    return null;
  }


  public boolean hasValidationInfo() {
    return validationInfo != null;
  }

  /**
   * A list of definitions that the validator matched this element to.
   * Note that the element doesn't have to conform to these definitions - check whether they're valid 
   * Some of the definitions will be noted because of slice matching
   * 
   * @return
   */
  public List<ValidationInfo> getValidationInfo() {
    return validationInfo;
  }

  public ValidationInfo addDefinition(StructureDefinition structure, ElementDefinition defn, ValidationMode mode) {
    if (validationInfo == null) {
      validationInfo = new ArrayList<>();
    }
    for (ValidationInfo t : validationInfo) {
      if (t.structure == structure && t.definition == defn && t.reason == mode.reason && t.source == mode.source) {
        return t;
      }
    }
    ValidationInfo vi = new ValidationInfo(structure, defn, mode);
    this.validationInfo.add(vi);
    return vi;
  }
  

  public boolean hasValidated(StructureDefinition sd, ElementDefinition ed) {
    if (validationInfo != null) {
      for (ValidationInfo vi : validationInfo) {
        if (vi.definition == ed && vi.structure == sd) {
          return true;
        }
      }
    }
    return false;
  }
  
  // validation messages: the validator does not populate these (yet)
  public Base addValidationMessage(ValidationMessage msg) {
    if (validationMessages == null) {
      validationMessages = new ArrayList<>();
    }
    validationMessages.add(msg);
    return this;
  }
  
  public boolean hasValidationMessages() {
    return validationMessages != null && !validationMessages.isEmpty();
  }
  
  public List<ValidationMessage> getValidationMessages() {
    return validationMessages != null ? validationMessages : new ArrayList<>();
  }

  public abstract FhirPublication getFHIRPublicationVersion();
  
  public List<Base> executeFunction(FHIRPathEngine engine, Object appContext, List<Base> focus, String functionName, List<List<Base>> parameters) {
    return new ArrayList<>();
  }

  
}