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// * to you under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance            *
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// *  http://www.apache.org/licenses/LICENSE-2.0                                                                             *
// *                                                                                                                         *
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// * specific language governing permissions and limitations under the License.                                              *
// ***************************************************************************************************************************
package org.apache.juneau.dto.swagger;

import static org.apache.juneau.internal.StringUtils.*;
import static org.apache.juneau.internal.CollectionUtils.*;
import static org.apache.juneau.internal.ConverterUtils.*;

import java.util.*;

import org.apache.juneau.annotation.*;
import org.apache.juneau.collections.*;
import org.apache.juneau.internal.*;

/**
 * Describes a single response from an API Operation.
 *
 * <h5 class='section'>Example:</h5>
 * <p class='bcode w800'>
 *    <jc>// Construct using SwaggerBuilder.</jc>
 *    ResponseInfo x = <jsm>responseInfo</jsm>(<js>"A complex object array response"</js>)
 *       .schema(
 *          <jsm>schemaInfo</jsm>
 *             .type(<js>"array"</js>)
 *             .items(
 *                <jsm>items</jsm>()
 *                   .set(<js>"$ref"</js>, <js>"#/definitions/VeryComplexType"</js>)
 *             )
 *       );
 *
 *    <jc>// Serialize using JsonSerializer.</jc>
 *    String json = JsonSerializer.<jsf>DEFAULT</jsf>.toString(x);
 *
 *    <jc>// Or just use toString() which does the same as above.</jc>
 *    String json = x.toString();
 * </p>
 * <p class='bcode w800'>
 *    <jc>// Output</jc>
 *    {
 *       <js>"description"</js>: <js>"A complex object array response"</js>,
 *       <js>"schema"</js>: {
 *          <js>"type"</js>: <js>"array"</js>,
 *          <js>"items"</js>: {
 *             <js>"$ref"</js>: <js>"#/definitions/VeryComplexType"</js>
 *          }
 *       }
 *    }
 * </p>
 *
 * <ul class='seealso'>
 *    <li class='link'>{@doc DtoSwagger}
 * </ul>
 */
@Bean(bpi="description,schema,headers,x-example,examples,*")
public class ResponseInfo extends SwaggerElement {

   private String description;
   private SchemaInfo schema;
   private Map<String,HeaderInfo> headers;
   private Object example;
   private Map<String,Object> examples;

   /**
    * Default constructor.
    */
   public ResponseInfo() {}

   /**
    * Copy constructor.
    *
    * @param copyFrom The object to copy.
    */
   public ResponseInfo(ResponseInfo copyFrom) {
      super(copyFrom);

      this.description = copyFrom.description;
      this.schema = copyFrom.schema == null ? null : copyFrom.schema.copy();

      if (copyFrom.headers == null) {
         this.headers = null;
      } else {
         this.headers = new LinkedHashMap<>();
         for (Map.Entry<String,HeaderInfo> e : copyFrom.headers.entrySet())
            this.headers.put(e.getKey(),  e.getValue().copy());
      }

      this.example = copyFrom.example;

      if (copyFrom.examples == null)
         this.examples = null;
      else
         this.examples = new LinkedHashMap<>(copyFrom.examples);
   }

   /**
    * Make a deep copy of this object.
    *
    * @return A deep copy of this object.
    */
   public ResponseInfo copy() {
      return new ResponseInfo(this);
   }

   /**
    * Copies any non-null fields from the specified object to this object.
    *
    * @param r
    *    The object to copy fields from.
    *    <br>Can be <jk>null</jk>.
    * @return This object (for method chaining).
    */
   public ResponseInfo copyFrom(ResponseInfo r) {
      if (r != null) {
         if (r.description != null)
            description = r.description;
         if (r.schema != null)
            schema = r.schema;
         if (r.headers != null)
            headers = r.headers;
         if (r.example != null)
            example = r.example;
         if (r.examples != null)
            examples = r.examples;
      }
      return this;
   }

   /**
    * Bean property getter:  <property>description</property>.
    *
    * <p>
    * A short description of the response.
    *
    * @return The property value, or <jk>null</jk> if it is not set.
    */
   public String getDescription() {
      return description;
   }

   /**
    * Bean property setter:  <property>description</property>.
    *
    * <p>
    * A short description of the response.
    *
    * @param value
    *    The new value for this property.
    *    <br>{@doc ExtGFM} can be used for rich text representation.
    *    <br>Property value is required.
    * @return This object (for method chaining).
    */
   public ResponseInfo setDescription(String value) {
      description = value;
      return this;
   }

   /**
    * Same as {@link #setDescription(String)}.
    *
    * @param value
    *    The new value for this property.
    *    <br>Non-String values will be converted to String using <c>toString()</c>.
    *    <br>Can be <jk>null</jk> to unset the property.
    * @return This object (for method chaining).
    */
   public ResponseInfo description(Object value) {
      return setDescription(stringify(value));
   }

   /**
    * Bean property getter:  <property>schema</property>.
    *
    * <p>
    * A definition of the response structure.
    *
    * <ul class='notes'>
    *    <li>
    *       If this field does not exist, it means no content is returned as part of the response.
    *    <li>
    *       As an extension to the {@doc ExtSwaggerSchemaObject Schema Object},
    *       its root type value may also be <js>"file"</js>.
    *    <li>
    *       This SHOULD be accompanied by a relevant produces mime-type.
    * </ul>
    *
    * @return The property value, or <jk>null</jk> if it is not set.
    */
   public SchemaInfo getSchema() {
      return schema;
   }

   /**
    * Bean property setter:  <property>schema</property>.
    *
    * <p>
    * A definition of the response structure.
    *
    * <ul class='notes'>
    *    <li>
    *       If this field does not exist, it means no content is returned as part of the response.
    *    <li>
    *       As an extension to the {@doc ExtSwaggerSchemaObject Schema Object},
    *       its root type value may also be <js>"file"</js>.
    *    <li>
    *       This SHOULD be accompanied by a relevant produces mime-type.
    * </ul>
    *
    * @param value
    *    The new value for this property.
    *    <br>It can be a primitive, an array or an object.
    *    <br>Can be <jk>null</jk> to unset the property.
    * @return This object (for method chaining).
    */
   public ResponseInfo setSchema(SchemaInfo value) {
      schema = value;
      return this;
   }

   /**
    * Same as {@link #setSchema(SchemaInfo)}.
    *
    * @param value
    *    The new value for this property.
    *    <br>Valid types:
    *    <ul>
    *       <li>{@link SchemaInfo}
    *       <li><c>String</c> - JSON object representation of {@link SchemaInfo}
    *          <p class='bcode w800'>
    *    <jc>// Example </jc>
    *    schema(<js>"{type:'type',description:'description',...}"</js>);
    *          </p>
    *    </ul>
    *    <br>Can be <jk>null</jk> to unset the property.
    * @return This object (for method chaining).
    */
   public ResponseInfo schema(Object value) {
      return setSchema(toType(value, SchemaInfo.class));
   }

   /**
    * Bean property getter:  <property>headers</property>.
    *
    * <p>
    * A list of headers that are sent with the response.
    *
    * @return The property value, or <jk>null</jk> if it is not set.
    */
   public Map<String,HeaderInfo> getHeaders() {
      return headers;
   }

   /**
    * Bean property setter:  <property>headers</property>.
    *
    * <p>
    * A list of headers that are sent with the response.
    *
    * @param value
    *    The new value for this property.
    *    <br>Can be <jk>null</jk> to unset the property.
    * @return This object (for method chaining).
    */
   public ResponseInfo setHeaders(Map<String,HeaderInfo> value) {
      headers = newMap(value);
      return this;
   }

   /**
    * Adds one or more values to the <property>headers</property> property.
    *
    * @param values
    *    The values to add to this property.
    *    <br>Ignored if <jk>null</jk>.
    * @return This object (for method chaining).
    */
   public ResponseInfo addHeaders(Map<String,HeaderInfo> values) {
      headers = addToMap(headers, values);
      return this;
   }

   /**
    * Adds a single value to the <property>headers</property> property.
    *
    * @param name The header name.
    * @param header The header descriptions
    * @return This object (for method chaining).
    */
   public ResponseInfo header(String name, HeaderInfo header) {
      addHeaders(Collections.singletonMap(name, header));
      return this;
   }

   /**
    * Adds one or more values to the <property>headers</property> property.
    *
    * @param values
    *    The values to add to this property.
    *    <br>Valid types:
    *    <ul>
    *       <li><c>Map&lt;String,{@link HeaderInfo}|String&gt;</c>
    *       <li><c>String</c> - JSON object representation of <c>Map&lt;String,{@link HeaderInfo}&gt;</c>
    *          <p class='bcode w800'>
    *    <jc>// Example </jc>
    *    headers(<js>"{headerName:{description:'description',...}}"</js>);
    *          </p>
    *    </ul>
    *    <br>Ignored if <jk>null</jk>.
    * @return This object (for method chaining).
    */
   public ResponseInfo headers(Object...values) {
      headers = addToMap(headers, values, String.class, HeaderInfo.class);
      return this;
   }

   /**
    * Returns the header information with the specified name.
    *
    * @param name The header name.
    * @return The header info, or <jk>null</jk> if not found.
    */
   public HeaderInfo getHeader(String name) {
      return getHeaders().get(name);
   }

   /**
    * Bean property getter:  <property>x-example</property>.
    *
    * @return The property value, or <jk>null</jk> if it is not set.
    */
   @Beanp("x-example")
   public Object getExample() {
      return example;
   }

   /**
    * Bean property setter:  <property>x-example</property>.
    *
    * @param value
    *    The new value for this property.
    *    <br>Can be <jk>null</jk> to unset the property.
    * @return This object (for method chaining).
    */
   @Beanp("x-example")
   public ResponseInfo setExample(Object value) {
      example = value;
      return this;
   }

   /**
    * Bean property setter:  <property>x-example</property>.
    *
    * @param value The property value.
    * @return This object (for method chaining).
    */
   public ResponseInfo example(Object value) {
      example = value;
      return this;
   }

   /**
    * Bean property getter:  <property>examples</property>.
    *
    * <p>
    * An example of the response message.
    *
    * @return The property value, or <jk>null</jk> if it is not set.
    */
   public Map<String,Object> getExamples() {
      return examples;
   }

   /**
    * Bean property setter:  <property>examples</property>.
    *
    * <p>
    * An example of the response message.
    *
    * @param value
    *    The new value for this property.
    *    <br>Keys must be MIME-type strings.
    *    <br>Can be <jk>null</jk> to unset the property.
    * @return This object (for method chaining).
    */
   public ResponseInfo setExamples(Map<String,Object> value) {
      examples = newMap(value);
      return this;
   }

   /**
    * Adds one or more values to the <property>examples</property> property.
    *
    * @param values
    *    The values to add to this property.
    *    <br>Ignored if <jk>null</jk>.
    * @return This object (for method chaining).
    */
   public ResponseInfo addExamples(Map<String,Object> values) {
      examples = addToMap(examples, values);
      return this;
   }

   /**
    * Adds a single value to the <property>examples</property> property.
    *
    * @param mimeType The mime-type string.
    * @param example The example.
    * @return This object (for method chaining).
    */
   public ResponseInfo example(String mimeType, Object example) {
      examples = addToMap(examples, mimeType, example);
      return this;
   }

   /**
    * Adds one or more values to the <property>examples</property> property.
    *
    * @param values
    *    The values to add to this property.
    *    <br>Valid types:
    *    <ul>
    *       <li><c>Map&lt;String,Object&gt;</c>
    *       <li><c>String</c> - JSON object representation of <c>Map&lt;String,Object&gt;</c>
    *          <p class='bcode w800'>
    *    <jc>// Example </jc>
    *    examples(<js>"{'text/json':{foo:'bar'}}"</js>);
    *          </p>
    *    </ul>
    *    <br>Ignored if <jk>null</jk>.
    * @return This object (for method chaining).
    */
   public ResponseInfo examples(Object...values) {
      examples = addToMap(examples, values, String.class, Object.class);
      return this;
   }

   @Override /* SwaggerElement */
   public <T> T get(String property, Class<T> type) {
      if (property == null)
         return null;
      switch (property) {
         case "description": return toType(getDescription(), type);
         case "schema": return toType(getSchema(), type);
         case "headers": return toType(getHeaders(), type);
         case "example": return toType(getExample(), type);
         case "examples": return toType(getExamples(), type);
         default: return super.get(property, type);
      }
   }

   @Override /* SwaggerElement */
   public ResponseInfo set(String property, Object value) {
      if (property == null)
         return this;
      switch (property) {
         case "description": return description(value);
         case "schema": return schema(value);
         case "headers": return setHeaders(null).headers(value);
         case "example": return setExample(value);
         case "examples": return setExamples(null).examples(value);
         default:
            super.set(property, value);
            return this;
      }
   }

   @Override /* SwaggerElement */
   public Set<String> keySet() {
      ASet<String> s = ASet.<String>of()
         .aif(description != null, "description")
         .aif(schema != null, "schema")
         .aif(headers != null, "headers")
         .aif(example != null, "example")
         .aif(examples != null, "examples");
      return new MultiSet<>(s, super.keySet());
   }

   /**
    * Returns <jk>true</jk> if this response info has headers associated with it.
    *
    * @return <jk>true</jk> if this response info has headers associated with it.
    */
   public boolean hasHeaders() {
      return headers != null && ! headers.isEmpty();
   }

   /**
    * Resolves any <js>"$ref"</js> attributes in this element.
    *
    * @param swagger The swagger document containing the definitions.
    * @param refStack Keeps track of previously-visited references so that we don't cause recursive loops.
    * @param maxDepth
    *    The maximum depth to resolve references.
    *    <br>After that level is reached, <c>$ref</c> references will be left alone.
    *    <br>Useful if you have very complex models and you don't want your swagger page to be overly-complex.
    * @return
    *    This object with references resolved.
    *    <br>May or may not be the same object.
    */
   public ResponseInfo resolveRefs(Swagger swagger, Deque<String> refStack, int maxDepth) {

      if (schema != null)
         schema = schema.resolveRefs(swagger, refStack, maxDepth);

      if (headers != null)
         for (Map.Entry<String,HeaderInfo> e : headers.entrySet())
            e.setValue(e.getValue().resolveRefs(swagger, refStack, maxDepth));

      return this;
   }
}