/*

 * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

 /*

  * This is the JavaCC grammar file for a JSON parser. The productions are

  * based on syntax diagrams as specified at json.org

  * Every type of JSON is represent by a JSONElement. JSON Objects are mapped to

  * by LinkedHashMap via JSONObject. JSON Arrays are mapped to ArrayList via JSONArray

  * String, Number, Boolean and null are wrapped into a JSONPrimitive.

  * Control characters inside a string (JSONPrimitive(String)) are not escaped and are passed through

  * to ouput JSON string generated by toJsonString method of JSONElement.

  * Inside a String, only backslash ('\') and double quote ('"') characters

  * are escaped by a backslash, if they are not already escaped.

  * Applications consuming json string generated by JSON* objects must take care

  * to escape control characters within strings by prefixing with a backslash character,

  * if not already escaped.

  */

options {

    STATIC=false;

    ERROR_REPORTING=true;

    JAVA_UNICODE_ESCAPE=true;

    UNICODE_INPUT=true;

    IGNORE_CASE=true;

    CACHE_TOKENS=true;

//    DEBUG_PARSER=true;

//    DEBUG_LOOKAHEAD=true;

//    DEBUG_TOKEN_MANAGER=true;

}

PARSER_BEGIN(JSONParser)

package com.oracle.jmx.remote.rest.json.parser;

import java.io.StringReader;

import com.oracle.jmx.remote.rest.json.*;

public class JSONParser {

    public JSONParser(String input) {

        this(new StringReader(input));

    }

    public JSONElement parse() throws ParseException {

        return jsonValue(); 

    }

}

PARSER_END(JSONParser)

SKIP: {

    " " | "\b" | "\t" | "\n" | "\r" | "\f"

}

TOKEN:{

   <INTEGER_LITERAL : (["-"])? (<DIGITS>)>

|   < FLOATING_POINT_LITERAL:

        <INTEGER_LITERAL> <FRAC>

|       <INTEGER_LITERAL> <EXPONENT>

|       <INTEGER_LITERAL> <FRAC> <EXPONENT>

    >

|   < #FRAC: "." <DIGITS>>

|   < #EXPONENT: ["e","E"] (["+","-"])? <DIGITS> >

|   < #DIGITS : (<DIGIT>)+>

|   < #DIGIT: ["0"-"9"]>

|   <QUOTED_STRING: "\"" ((~["\"","\\"]) | ("\\" ( ["n","t","b","r","f","\\","\""])))* "\"">

|   <NULL: "null">

}

JSONElement jsonValue() : {

	JSONElement x;

}{

	( x = object()

	| x = list()

	| x = string()

	| x = number()

	| x = boolVal()

	| x = nullVal()

	)

	{ return x; }

}

JSONObject object() : {

	final JSONObject jobject = new JSONObject();

	JSONPrimitive key;

	JSONElement value;

}{

    "{"

        (key = string())

        ":"

        value = jsonValue()

        { jobject.put((String)key.getValue(), value);}

        (

                ","

                (key = string())

                ":"

                value = jsonValue()

                { jobject.put((String)key.getValue(), value);}

        )*

    "}"

    { return jobject; }

}

JSONArray list() : {

    final JSONArray jarray = new JSONArray();

    JSONElement value;

}{

    "["

        value = jsonValue()

        { jarray.add(value);}

        (

            ","

            value = jsonValue()

            { jarray.add(value); }

        )*

    "]"

    { return jarray; }

}

JSONPrimitive nullVal(): {} {

    <NULL>

    { return null; }

}

JSONPrimitive boolVal(): {}

{

    <BOOL_LITERAL>

    {return new JSONPrimitive(Boolean.parseBoolean(token.image));}

}

JSONPrimitive number(): {

    Token t;

}{

    (t = <INTEGER_LITERAL> { return new JSONPrimitive(Long.parseLong(t.image));})

    | (t = <FLOATING_POINT_LITERAL> { return new JSONPrimitive(Double.parseDouble(t.image));})

}

JSONPrimitive string() : {

    Token t;

}{

    (t = <QUOTED_STRING>)

    { return new JSONPrimitive(t.image.substring(1,t.image.length()-1)); }

}