/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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.
 */
package org.apache.juneau.marshall.serializer;

import static org.apache.juneau.commons.utils.IoUtils.*;
import static org.apache.juneau.commons.utils.Shorts.*;
import static org.apache.juneau.commons.utils.SystemUtils.*;
import static org.apache.juneau.commons.utils.ThrowableUtils.*;

import java.nio.charset.*;

import org.apache.juneau.commons.collections.*;
import org.apache.juneau.commons.function.*;
import org.apache.juneau.commons.logging.*;
import org.apache.juneau.marshall.json5.*;

/**
 * Subclass of {@link Serializer} for character-based serializers.
 *
 * <h5 class='section'>Notes:</h5><ul>
 *    <li class='note'>This class is thread safe and reusable.
 * </ul>
 *
 * <h5 class='section'>See Also:</h5><ul>
 *    <li class='link'><a class="doclink" href="https://juneau.apache.org/docs/topics/SerializersAndParsers">Serializers and Parsers</a>
 * </ul>
 */
@SuppressWarnings({
   "java:S1192", // Duplicated literals (argument/property names) read more clearly inline than as constants
   "java:S9149" // Per-format static factories intentionally shadow the parent's.
})
public class WriterSerializer extends Serializer implements ThrowingFunction<Object,String> {

   /**
    * Builder class.
    */
   @SuppressWarnings({
      "java:S119" // 'SELF' (CRTP self-type) is intentional and clearer than a single-letter name.
   })
   public abstract static class Builder<SELF extends Builder<SELF>> extends Serializer.Builder<SELF> {

      private boolean useWhitespace;
      private Character quoteChar;
      private Character quoteCharOverride;
      private Charset streamCharset;
      private int maxIndent;

      /**
       * Constructor, default settings.
       */
      protected Builder() {
         streamCharset = UTF8;
         maxIndent = env("WriterSerializer.maxIndent", 100);
         quoteChar = env("WriterSerializer.quoteChar").map(x -> (x.isEmpty() ? null : x.charAt(0))).orElse(null);
         quoteCharOverride = env("WriterSerializer.quoteCharOverride").map(x -> (x.isEmpty() ? null : x.charAt(0))).orElse(null);
         useWhitespace = env("WriterSerializer.useWhitespace", false);
      }

      /**
       * Copy constructor.
       *
       * @param copyFrom The builder to copy from.
       *    <br>Cannot be <jk>null</jk>.
       */
      protected Builder(Builder<?> copyFrom) {
         super(reqnn("copyFrom", copyFrom));
         streamCharset = copyFrom.streamCharset;
         maxIndent = copyFrom.maxIndent;
         quoteChar = copyFrom.quoteChar;
         quoteCharOverride = copyFrom.quoteCharOverride;
         useWhitespace = copyFrom.useWhitespace;
      }

      /**
       * Copy constructor.
       *
       * @param copyFrom The bean to copy from.
       *    <br>Cannot be <jk>null</jk>.
       */
      protected Builder(WriterSerializer copyFrom) {
         super(reqnn("copyFrom", copyFrom));
         streamCharset = copyFrom.getStreamCharset();
         maxIndent = copyFrom.maxIndent;
         quoteChar = copyFrom.quoteChar;
         quoteCharOverride = copyFrom.quoteCharOverride;
         useWhitespace = copyFrom.useWhitespace;
      }

      @Override /* Overridden from Context.Builder<?> */
      public WriterSerializer build() {
         return build(WriterSerializer.class);
      }

      @Override /* Overridden from Context.Builder<?> */
      public abstract SELF copy();

      @Override /* Overridden from Context.Builder<?> */
      public HashKey hashKey() {
         // @formatter:off
         return HashKey.of(
            super.hashKey(),
            streamCharset,
            maxIndent,
            quoteChar,
            quoteCharOverride,
            useWhitespace
         );
         // @formatter:on
      }

      /**
       * Maximum indentation.
       *
       * <p>
       * Specifies the maximum indentation level in the serialized document.
       *
       * <h5 class='section'>Notes:</h5><ul>
       *    <li class='note'>This setting does not apply to the RDF serializers.
       * </ul>
       *
       * <h5 class='section'>Example:</h5>
       * <p class='bjava'>
       *    <jc>// Create a serializer that indents a maximum of 20 tabs.</jc>
       *    WriterSerializer <jv>serializer</jv> = JsonSerializer
       *       .<jsm>create</jsm>()
       *       .ws()  <jc>// Enable whitespace</jc>
       *       .maxIndent(20)
       *       .build();
       * </p>
       *
       * @param value
       *    The new value for this property.
       *    <br>The default is <c>100</c>.
       * @return This object.
       */
      public SELF maxIndent(int value) {
         maxIndent = value;
         return self();
      }

      /**
       *  Quote character.
       *
       * <p>
       * Specifies the character to use for quoting attributes and values.
       *
       * <h5 class='section'>Notes:</h5><ul>
       *    <li class='note'>This setting does not apply to the RDF serializers.
       * </ul>
       *
       * <h5 class='section'>Example:</h5>
       * <p class='bjava'>
       *    <jc>// Create a serializer that uses single quotes.</jc>
       *    WriterSerializer <jv>serializer</jv> = JsonSerializer
       *       .<jsm>create</jsm>()
       *       .quoteChar(<js>'\''</js>)
       *       .build();
       *
       *    <jc>// A bean with a single property</jc>
       *    <jk>public class</jk> MyBean {
       *       <jk>public</jk> String <jf>foo</jf> = <js>"bar"</js>;
       *    }
       *
       *    <jc>// Produces {'foo':'bar'}</jc>
       *    String <jv>json</jv> = <jv>serializer</jv>.toString(<jk>new</jk> MyBean());
       * </p>
       *
       * @param value
       *    The new value for this property.
       *    <br>The default is <js>'"'</js>.
       * @return This object.
       */
      public SELF quoteChar(char value) {
         quoteChar = value;
         return self();
      }

      /**
       * Quote character override.
       *
       * <p>
       * Similar to {@link #quoteChar(char)} but takes precedence over that setting.
       *
       * <p>
       * Allows you to override the quote character even if it's set by a subclass such as {@link Json5Serializer}.
       *
       *
       * @param value
       *    The new value for this property.
       *    <br>The default is <jk>null</jk>.
       * @return This object.
       */
      public SELF quoteCharOverride(char value) {
         quoteCharOverride = value;
         return self();
      }

      /**
       *  Quote character.
       *
       * <p>
       * Specifies to use single quotes for quoting attributes and values.
       *
       * <h5 class='section'>Notes:</h5><ul>
       *    <li class='note'>This setting does not apply to the RDF serializers.
       * </ul>
       *
       * <h5 class='section'>Example:</h5>
       * <p class='bjava'>
       *    <jc>// Create a serializer that uses single quotes.</jc>
       *    WriterSerializer <jv>serializer</jv> = JsonSerializer
       *       .<jsm>create</jsm>()
       *       .sq()
       *       .build();
       *
       *    <jc>// A bean with a single property</jc>
       *    <jk>public class</jk> MyBean {
       *       <jk>public</jk> String <jf>foo</jf> = <js>"bar"</js>;
       *    }
       *
       *    <jc>// Produces {'foo':'bar'}</jc>
       *    String <jv>json</jv> = <jv>serializer</jv>.toString(<jk>new</jk> MyBean());
       * </p>
       *
       * @return This object.
       */
      public SELF sq() {
         return quoteChar('\'');
      }

      /**
       * Output stream charset.
       *
       * <p>
       * The character set to use when writing to <c>OutputStreams</c>.
       *
       * <p>
       * Used when passing in output streams and byte arrays to {@link WriterSerializer#write(Object, Object)}.
       *
       * <h5 class='section'>Example:</h5>
       * <p class='bjava'>
       *    <jc>// Create a serializer that writes UTF-8 files.</jc>
       *    WriterSerializer <jv>serializer</jv> = JsonSerializer
       *       .<jsm>create</jsm>()
       *       .streamCharset(Charset.<jsm>forName</jsm>(<js>"UTF-8"</js>))
       *       .build();
       *
       *    <jc>// Use it to write to a UTF-8 encoded output stream.</jc>
       *    <jv>serializer</jv>.serializer(<jk>new</jk> FileOutputStreamStream(<js>"MyBean.txt"</js>), <jv>myBean</jv>);
       * </p>
       *
       * @param value
       *    The new value for this property.
       *    <br>The default is the system JVM setting.
       *    <br>Can be <jk>null</jk> (defaults to UTF-8).
       * @return This object.
       */
      public SELF streamCharset(Charset value) {
         streamCharset = value;
         return self();
      }


      /**
       *  Use whitespace.
       *
       * <p>
       * When enabled, whitespace is added to the output to improve readability.
       *
       * <h5 class='section'>Example:</h5>
       * <p class='bjava'>
       *    <jc>// Create a serializer with whitespace enabled.</jc>
       *    WriterSerializer <jv>serializer</jv> = JsonSerializer
       *       .<jsm>create</jsm>()
       *       .useWhitespace()
       *       .build();
       *
       *    <jc>// A bean with a single property</jc>
       *    <jk>public class</jk> MyBean {
       *       <jk>public</jk> String <jf>foo</jf> = <js>"bar"</js>;
       *    }
       *
       *    <jc>// Produces "\{\n\t"foo": "bar"\n\}\n"</jc>
       *    String <jv>json</jv> = <jv>serializer</jv>.write(<jk>new</jk> MyBean());
       * </p>
       *
       * @return This object.
       */
      public SELF useWhitespace() {
         return useWhitespace(true);
      }

      /**
       * Same as {@link #useWhitespace()} but allows you to explicitly specify the value.
       *
       * @param value The value for this setting.
       * @return This object.
       */
      public SELF useWhitespace(boolean value) {
         useWhitespace = value;
         return self();
      }

      /**
       *  Use whitespace.
       *
       * <p>
       * When enabled, whitespace is added to the output to improve readability.
       *
       * <h5 class='section'>Example:</h5>
       * <p class='bjava'>
       *    <jc>// Create a serializer with whitespace enabled.</jc>
       *    WriterSerializer <jv>serializer</jv> = JsonSerializer
       *       .<jsm>create</jsm>()
       *       .ws()
       *       .build();
       *
       *    <jc>// A bean with a single property</jc>
       *    <jk>public class</jk> MyBean {
       *       <jk>public</jk> String <jf>foo</jf> = <js>"bar"</js>;
       *    }
       *
       *    <jc>// Produces "\{\n\t"foo": "bar"\n\}\n"</jc>
       *    String <jv>json</jv> = <jv>serializer</jv>.write(<jk>new</jk> MyBean());
       * </p>
       *
       * @return This object.
       */
      public SELF ws() {
         return useWhitespace();
      }
   }

   /**
    * Concrete default builder leaf for the non-subclassed {@link WriterSerializer#create()} / {@link WriterSerializer#copy()} path.
    */
   @SuppressWarnings({
      "java:S110" // Inheritance depth follows the serializer builder chain; intentional layered design
   })
   public static final class DefaultBuilder extends Builder<DefaultBuilder> {

      DefaultBuilder() {}

      DefaultBuilder(WriterSerializer copyFrom) {
         super(copyFrom);
      }

      DefaultBuilder(Builder<?> copyFrom) {
         super(copyFrom);
      }

      @Override /* Overridden from Context.Builder<?> */
      public DefaultBuilder copy() {
         return new DefaultBuilder(this);
      }
   }

   /**
    * Creates a new builder for this object.
    *
    * @return A new builder.
    */
   @SuppressWarnings({
      "java:S1452" // Builder<?> wildcard return intentional; callers chain via fluent API without needing the concrete type
   })
   public static Builder<?> create() {
      return new DefaultBuilder();
   }

   protected final boolean useWhitespace;
   protected final Character quoteChar;
   protected final Character quoteCharOverride;
   private final Charset streamCharset;
   protected final int maxIndent;

   private final char quoteCharValue;

   /**
    * Constructor.
    *
    * @param builder
    *    The builder for this object.
    *    <br>Cannot be <jk>null</jk>.
    */
   protected WriterSerializer(Builder<?> builder) {
      super(builder);

      maxIndent = builder.maxIndent;
      quoteChar = builder.quoteChar;
      quoteCharOverride = builder.quoteCharOverride;
      streamCharset = builder.streamCharset;
      useWhitespace = builder.useWhitespace;

      if (nn(quoteCharOverride)) {
         quoteCharValue = quoteCharOverride;
      } else if (nn(quoteChar)) {
         quoteCharValue = quoteChar;
      } else {
         quoteCharValue = '"';
      }
   }

   @Override /* Overridden from Context */
   public Builder<?> copy() {
      return new DefaultBuilder(this);
   }

   @Override /* Overridden from Context */
   public WriterSerializerSession.Builder<?> createSession() {
      return WriterSerializerSession.create(this);
   }

   @Override /* Overridden from Context */
   public WriterSerializerSession getSession() { return createSession().build(); }

   @Override /* Overridden from Serializer */
   public final boolean isWriterSerializer() { return true; }

   /**
    * Convenience method for serializing an object and sending it to STDOUT.
    *
    * @param o The object to serialize.
    * @return This object.
    */
   public final WriterSerializer println(Object o) {
      RichLogger.getLogger(WriterSerializer.class).info(toString(o));  // NOT DEBUG
      return this;
   }

   /**
    * Convenience method for serializing an object to a <c>String</c>.
    *
    * @param o The object to serialize.
    * @return The output serialized to a string.
    * @throws SerializeException If a problem occurred trying to convert the output.
    */
   @Override /* Overridden from Serializer */
   public final String write(Object o) throws SerializeException {
      return getSession().write(o);
   }

   /**
    * Allows this serializer to be used as a {@link ThrowingFunction} that converts an object to its serialized string form.
    *
    * <p>
    * Because {@link WriterSerializer} implements {@link ThrowingFunction ThrowingFunction&lt;Object,String&gt;}, a serializer
    * instance can be passed directly wherever a {@link java.util.function.Function Function} or {@link ThrowingFunction} is
    * expected (e.g. assertion transform methods).
    *
    * <h5 class='section'>Example:</h5>
    * <p class='bjava'>
    *    <jsm>assertObject</jsm>(<jv>myPojo</jv>).asString(Json5Serializer.<jsf>DEFAULT</jsf>).is(<js>"{...}"</js>);
    * </p>
    *
    * @param o The object to serialize.
    * @return The output serialized to a string.
    * @throws Exception If a problem occurred trying to convert the output.
    */
   @Override /* Overridden from ThrowingFunction */
   public final String applyThrows(Object o) throws Exception {
      return write(o);
   }

   /**
    * Identical to {@link #write(Object)} except throws a {@link RuntimeException} instead of a {@link SerializeException}.
    *
    * <p>
    * This is typically good enough for debugging purposes.
    *
    * @param o The object to serialize.
    * @return The serialized object.
    */
   public final String toString(Object o) {
      try {
         return write(o);
      } catch (Exception e) {
         throw toRex(e);
      }
   }

   /**
    * Maximum indentation.
    *
    * @see Builder#maxIndent(int)
    * @return
    *    The maximum indentation level in the serialized document.
    */
   protected final int getMaxIndent() { return maxIndent; }

   /**
    * Quote character.
    *
    * @see Builder#quoteChar(char)
    * @return
    *    The character used for quoting attributes and values.
    */
   protected char getQuoteChar() { return quoteCharValue; }

   /**
    * Output stream charset.
    *
    * @see Builder#streamCharset(Charset)
    * @return
    *    The character set to use when writing to <c>OutputStreams</c> and byte arrays.
    */
   protected final Charset getStreamCharset() { return streamCharset; }

   /**
    * Use whitespace.
    *
    * @see Builder#useWhitespace()
    * @return
    *    When enabled, whitespace is added to the output to improve readability.
    */
   protected final boolean isUseWhitespace() { return useWhitespace; }

   @Override /* Overridden from Serializer */
   protected FluentMap<String,Object> properties() {
      return super.properties()
         .a("maxIndent", maxIndent)
         .a("quoteChar", quoteChar)
         .a("streamCharset", streamCharset)
         .a("useWhitespace", useWhitespace);
   }

   /**
    * Quote character.
    *
    * @see Builder#quoteChar(char)
    * @return
    *    The character used for quoting attributes and values.
    */
   @SuppressWarnings({
      "java:S1845" // Method name intentionally matches field name
   })
   protected Character quoteChar() {
      return nn(quoteCharOverride) ? quoteCharOverride : quoteChar;
   }
}