﻿/*
 * Copyright (c) 2013 Calvin Rien
 *
 * Based on the JSON parser by Patrick van Bergen
 * http://techblog.procurios.nl/k/618/news/view/14605/14863/How-do-I-write-my-own-parser-for-JSON.html
 *
 * Simplified it so that it doesn't throw exceptions
 * and can be used in Unity iPhone with maximum code stripping.
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
 * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */
using System;
using System.Collections;
using System.Collections.Generic;
using System.Globalization;
using System.IO;
using System.Text;

namespace UnityEngine.Purchasing
{
    namespace MiniJSON
    {
        // Example usage:
        //
        //  using UnityEngine;
        //  using System.Collections;
        //  using System.Collections.Generic;
        //  using MiniJSON;
        //
        //  public class MiniJSONTest : MonoBehaviour {
        //      void Start () {
        //          var jsonString = "{ \"array\": [1.44,2,3], " +
        //                          "\"object\": {\"key1\":\"value1\", \"key2\":256}, " +
        //                          "\"string\": \"The quick brown fox \\\"jumps\\\" over the lazy dog \", " +
        //                          "\"unicode\": \"\\u3041 Men\u00fa sesi\u00f3n\", " +
        //                          "\"int\": 65536, " +
        //                          "\"float\": 3.1415926, " +
        //                          "\"bool\": true, " +
        //                          "\"null\": null }";
        //
        //          var dict = Json.Deserialize(jsonString) as Dictionary<string,object>;
        //
        //          Debug.Log("deserialized: " + dict.GetType());
        //          Debug.Log("dict['array'][0]: " + ((List<object>) dict["array"])[0]);
        //          Debug.Log("dict['string']: " + (string) dict["string"]);
        //          Debug.Log("dict['float']: " + (double) dict["float"]); // floats come out as doubles
        //          Debug.Log("dict['int']: " + (long) dict["int"]); // ints come out as longs
        //          Debug.Log("dict['unicode']: " + (string) dict["unicode"]);
        //
        //          var str = Json.Serialize(dict);
        //
        //          Debug.Log("serialized: " + str);
        //      }
        //  }

        /// <summary>
        /// This class encodes and decodes JSON strings.
        /// Spec. details, see http://www.json.org/
        ///
        /// JSON uses Arrays and Objects. These correspond here to the datatypes IList and IDictionary.
        /// All numbers are parsed to doubles.
        /// </summary>
        public static class Json
        {
            /// <summary>
            /// Parses the string json into a value
            /// </summary>
            /// <param name="json">A JSON string.</param>
            /// <returns>An List&lt;object&gt;, a Dictionary&lt;string, object&gt;, a double, an integer,a string, null, true, or false</returns>
            public static object Deserialize (string json)
            {
                // save the string for debug information
                if (json == null) {
                    return null;
                }

                return Parser.Parse (json);
            }

            sealed class Parser : IDisposable
            {
                const string WORD_BREAK = "{}[],:\"";

                public static bool IsWordBreak (char c)
                {
                    return Char.IsWhiteSpace (c) || WORD_BREAK.IndexOf (c) != -1;
                }

                enum TOKEN
                {
                    NONE,
                    CURLY_OPEN,
                    CURLY_CLOSE,
                    SQUARED_OPEN,
                    SQUARED_CLOSE,
                    COLON,
                    COMMA,
                    STRING,
                    NUMBER,
                    TRUE,
                    FALSE,
                    NULL
                };

                StringReader json;

                Parser (string jsonString)
                {
                    json = new StringReader (jsonString);
                }

                public static object Parse (string jsonString)
                {
                    using (var instance = new Parser (jsonString)) {
                        return instance.ParseValue ();
                    }
                }

                public void Dispose ()
                {
                    json.Dispose ();
                    json = null;
                }

                Dictionary<string, object> ParseObject ()
                {
                    Dictionary<string, object> table = new Dictionary<string, object> ();

                    // ditch opening brace
                    json.Read ();

                    // {
                    while (true) {
                        switch (NextToken) {
                        case TOKEN.NONE:
                            return null;
                        case TOKEN.COMMA:
                            continue;
                        case TOKEN.CURLY_CLOSE:
                            return table;
                        default:
                            // name
                            string name = ParseString ();
                            if (name == null) {
                                return null;
                            }

                            // :
                            if (NextToken != TOKEN.COLON) {
                                return null;
                            }
                            // ditch the colon
                            json.Read ();

                            // value
                            table [name] = ParseValue ();
                            break;
                        }
                    }
                }

                List<object> ParseArray ()
                {
                    List<object> array = new List<object> ();

                    // ditch opening bracket
                    json.Read ();

                    // [
                    var parsing = true;
                    while (parsing) {
                        TOKEN nextToken = NextToken;

                        switch (nextToken) {
                        case TOKEN.NONE:
                            return null;
                        case TOKEN.COMMA:
                            continue;
                        case TOKEN.SQUARED_CLOSE:
                            parsing = false;
                            break;
                        default:
                            object value = ParseByToken (nextToken);

                            array.Add (value);
                            break;
                        }
                    }

                    return array;
                }

                object ParseValue ()
                {
                    TOKEN nextToken = NextToken;
                    return ParseByToken (nextToken);
                }

                object ParseByToken (TOKEN token)
                {
                    switch (token) {
                    case TOKEN.STRING:
                        return ParseString ();
                    case TOKEN.NUMBER:
                        return ParseNumber ();
                    case TOKEN.CURLY_OPEN:
                        return ParseObject ();
                    case TOKEN.SQUARED_OPEN:
                        return ParseArray ();
                    case TOKEN.TRUE:
                        return true;
                    case TOKEN.FALSE:
                        return false;
                    case TOKEN.NULL:
                        return null;
                    default:
                        return null;
                    }
                }

                string ParseString ()
                {
                    StringBuilder s = new StringBuilder ();
                    char c;

                    // ditch opening quote
                    json.Read ();

                    bool parsing = true;
                    while (parsing) {

                        if (json.Peek () == -1) {
                            parsing = false;
                            break;
                        }

                        c = NextChar;
                        switch (c) {
                        case '"':
                            parsing = false;
                            break;
                        case '\\':
                            if (json.Peek () == -1) {
                                parsing = false;
                                break;
                            }

                            c = NextChar;
                            switch (c) {
                            case '"':
                            case '\\':
                            case '/':
                                s.Append (c);
                                break;
                            case 'b':
                                s.Append ('\b');
                                break;
                            case 'f':
                                s.Append ('\f');
                                break;
                            case 'n':
                                s.Append ('\n');
                                break;
                            case 'r':
                                s.Append ('\r');
                                break;
                            case 't':
                                s.Append ('\t');
                                break;
                            case 'u':
                                var hex = new char [4];

                                for (int i = 0; i < 4; i++) {
                                    hex [i] = NextChar;
                                }

                                s.Append ((char)Convert.ToInt32 (new string (hex), 16));
                                break;
                            }
                            break;
                        default:
                            s.Append (c);
                            break;
                        }
                    }

                    return s.ToString ();
                }

                object ParseNumber ()
                {
                    string number = NextWord;

					if (number.IndexOf ('.') == -1 && number.IndexOf ('e') == -1 && number.IndexOf ('E') == -1) {
                        long parsedInt;
                        Int64.TryParse (number, NumberStyles.Any, CultureInfo.InvariantCulture, out parsedInt);
                        return parsedInt;
                    }

                    double parsedDouble;
                    Double.TryParse (number, NumberStyles.Any, CultureInfo.InvariantCulture, out parsedDouble);
                    return parsedDouble;
                }

                void EatWhitespace ()
                {
                    while (Char.IsWhiteSpace (PeekChar)) {
                        json.Read ();

                        if (json.Peek () == -1) {
                            break;
                        }
                    }
                }

                char PeekChar {
                    get {
                        return Convert.ToChar (json.Peek ());
                    }
                }

                char NextChar {
                    get {
                        return Convert.ToChar (json.Read ());
                    }
                }

                string NextWord {
                    get {
                        StringBuilder word = new StringBuilder ();

                        while (!IsWordBreak (PeekChar)) {
                            word.Append (NextChar);

                            if (json.Peek () == -1) {
                                break;
                            }
                        }

                        return word.ToString ();
                    }
                }

                TOKEN NextToken {
                    get {
                        EatWhitespace ();

                        if (json.Peek () == -1) {
                            return TOKEN.NONE;
                        }

                        switch (PeekChar) {
                        case '{':
                            return TOKEN.CURLY_OPEN;
                        case '}':
                            json.Read ();
                            return TOKEN.CURLY_CLOSE;
                        case '[':
                            return TOKEN.SQUARED_OPEN;
                        case ']':
                            json.Read ();
                            return TOKEN.SQUARED_CLOSE;
                        case ',':
                            json.Read ();
                            return TOKEN.COMMA;
                        case '"':
                            return TOKEN.STRING;
                        case ':':
                            return TOKEN.COLON;
                        case '0':
                        case '1':
                        case '2':
                        case '3':
                        case '4':
                        case '5':
                        case '6':
                        case '7':
                        case '8':
                        case '9':
                        case '-':
                            return TOKEN.NUMBER;
                        }

                        switch (NextWord) {
                        case "false":
                            return TOKEN.FALSE;
                        case "true":
                            return TOKEN.TRUE;
                        case "null":
                            return TOKEN.NULL;
                        }

                        return TOKEN.NONE;
                    }
                }
            }

            /// <summary>
            /// Converts a IDictionary / IList object or a simple type (string, int, etc.) into a JSON string
            /// </summary>
            /// <param name="obj">A Dictionary&lt;string, object&gt; / List&lt;object&gt;</param>
            /// <returns>A JSON encoded string, or null if object 'json' is not serializable</returns>
            public static string Serialize (object obj)
            {
                return Serializer.Serialize (obj);
            }

            sealed class Serializer
            {
                StringBuilder builder;

                Serializer ()
                {
                    builder = new StringBuilder ();
                }

                public static string Serialize (object obj)
                {
                    var instance = new Serializer ();

                    instance.SerializeValue (obj);

                    return instance.builder.ToString ();
                }

                void SerializeValue (object value)
                {
                    IList asList;
                    IDictionary asDict;
                    string asStr;

                    if (value == null) {
                        builder.Append ("null");
                    } else if ((asStr = value as string) != null) {
                        SerializeString (asStr);
                    } else if (value is bool) {
                        builder.Append ((bool)value ? "true" : "false");
                    } else if ((asList = value as IList) != null) {
                        SerializeArray (asList);
                    } else if ((asDict = value as IDictionary) != null) {
                        SerializeObject (asDict);
                    } else if (value is char) {
                        SerializeString (new string ((char)value, 1));
                    } else {
                        SerializeOther (value);
                    }
                }

                void SerializeObject (IDictionary obj)
                {
                    bool first = true;

                    builder.Append ('{');

                    foreach (object e in obj.Keys) {
                        if (!first) {
                            builder.Append (',');
                        }

                        SerializeString (e.ToString ());
                        builder.Append (':');

                        SerializeValue (obj [e]);

                        first = false;
                    }

                    builder.Append ('}');
                }

                void SerializeArray (IList anArray)
                {
                    builder.Append ('[');

                    bool first = true;

                    foreach (object obj in anArray) {
                        if (!first) {
                            builder.Append (',');
                        }

                        SerializeValue (obj);

                        first = false;
                    }

                    builder.Append (']');
                }

                void SerializeString (string str)
                {
                    builder.Append ('\"');

                    char [] charArray = str.ToCharArray ();
                    foreach (var c in charArray) {
                        switch (c) {
                        case '"':
                            builder.Append ("\\\"");
                            break;
                        case '\\':
                            builder.Append ("\\\\");
                            break;
                        case '\b':
                            builder.Append ("\\b");
                            break;
                        case '\f':
                            builder.Append ("\\f");
                            break;
                        case '\n':
                            builder.Append ("\\n");
                            break;
                        case '\r':
                            builder.Append ("\\r");
                            break;
                        case '\t':
                            builder.Append ("\\t");
                            break;
                        default:
                            int codepoint = Convert.ToInt32 (c);
                            if ((codepoint >= 32) && (codepoint <= 126)) {
                                builder.Append (c);
                            } else {
                                builder.Append ("\\u");
                                builder.Append (codepoint.ToString ("x4"));
                            }
                            break;
                        }
                    }

                    builder.Append ('\"');
                }

                void SerializeOther (object value)
                {
                    // Ensure we serialize Numbers using decimal (.) characters; avoid using comma (,) for
                    // decimal separator. Use CultureInfo.InvariantCulture.

                    // NOTE: decimals lose precision during serialization.
                    // They always have, I'm just letting you know.
                    // Previously floats and doubles lost precision too.
                    if (value is float) {
                        builder.Append (((float)value).ToString ("R", CultureInfo.InvariantCulture));
                    } else if (value is int
                               || value is uint
                               || value is long
                               || value is sbyte
                               || value is byte
                               || value is short
                               || value is ushort
                               || value is ulong) {
                        builder.Append (value);
                    } else if (value is double
                               || value is decimal) {
                        builder.Append (Convert.ToDouble (value).ToString ("R", CultureInfo.InvariantCulture));
                    } else {
                        SerializeString (value.ToString ());
                    }
                }
            }
        }

    // By Unity
    #region Extension methods

    /// <summary>
    /// Extension class for MiniJson to access values in JSON format.
    /// </summary>
    public static class MiniJsonExtensions
    {
        /// <summary>
        /// Get the HashDictionary of a key in JSON dictionary.
        /// </summary>
        /// <param name="dic">The JSON in dictionary representations.</param>
        /// <param name="key">The Key to get the HashDictionary from in the JSON dictionary.</param>
        /// <returns>The HashDictionary found in the JSON</returns>
        public static Dictionary<string, object> GetHash(this Dictionary<string, object> dic, string key)
        {
            return (Dictionary<string, object>) dic[key];
        }

        /// <summary>
        /// Get the casted enum in the JSON dictionary.
        /// </summary>
        /// <param name="dic">The JSON in dictionary representations.</param>
        /// <param name="key">The Key to get the casted enum from in the JSON dictionary.</param>
        /// <typeparam name="T">The class to cast the enum.</typeparam>
        /// <returns>The casted enum or will return T if the key was not found in the JSON dictionary.</returns>
        public static T GetEnum<T>(this Dictionary<string, object> dic, string key)
        {
            if (dic.ContainsKey(key))
                return (T) Enum.Parse(typeof (T), dic[key].ToString(), true);

            return default(T);
        }

        /// <summary>
        /// Get the string in the JSON dictionary.
        /// </summary>
        /// <param name="dic">The JSON in dictionary representations.</param>
        /// <param name="key">The Key to get the string from in the JSON dictionary.</param>
        /// <param name="defaultValue">The default value to send back if the JSON dictionary doesn't contains the key.</param>
        /// <returns>The string from the JSON dictionary or the default value if there is none</returns>
        public static string GetString(this Dictionary<string, object> dic, string key, string defaultValue = "")
        {
            if (dic.ContainsKey(key))
                return dic[key].ToString();

            return defaultValue;
        }

        /// <summary>
        /// Get the long in the JSON dictionary.
        /// </summary>
        /// <param name="dic">The JSON in dictionary representations.</param>
        /// <param name="key">The Key to get the long from in the JSON dictionary.</param>
        /// <returns>The long from the JSON dictionary or 0 if the key was not found in the JSON dictionary</returns>
        public static long GetLong(this Dictionary<string, object> dic, string key)
        {
            if (dic.ContainsKey(key))
                return long.Parse(dic[key].ToString());

            return 0;
        }

        /// <summary>
        /// Get the list of strings in the JSON dictionary.
        /// </summary>
        /// <param name="dic">The JSON in dictionary representations.</param>
        /// <param name="key">The Key to get the list of strings from in the JSON dictionary.</param>
        /// <returns>The list of strings from the JSON dictionary or an empty list of strings if the key was not found in the JSON dictionary</returns>
        public static List<string> GetStringList(this Dictionary<string, object> dic, string key)
        {
            if (dic.ContainsKey(key))
            {
                List<string> result = new List<string>();
                var objs = (List<object>) dic[key];
                foreach (var v in objs)
                    result.Add(v.ToString());
                return result;
            }

            return new List<string>();
        }

        /// <summary>
        /// Get the bool in the JSON dictionary.
        /// </summary>
        /// <param name="dic">The JSON in dictionary representations.</param>
        /// <param name="key">The Key to get the bool from in the JSON dictionary.</param>
        /// <returns>The bool from the JSON dictionary or false if the key was not found in the JSON dictionary</returns>
        public static bool GetBool(this Dictionary<string, object> dic, string key)
        {
            if (dic.ContainsKey(key))
                return bool.Parse(dic[key].ToString());

            return false;
        }

        /// <summary>
        /// Get the casted object in the JSON dictionary.
        /// </summary>
        /// <param name="dic">The JSON in dictionary representations.</param>
        /// <param name="key">The Key to get the casted object from in the JSON dictionary.</param>
        /// <typeparam name="T">The class to cast the object.</typeparam>
        /// <returns>The casted object or will return T if the key was not found in the JSON dictionary.</returns>
        public static T Get<T>(this Dictionary<string, object> dic, string key)
        {
            if (dic.ContainsKey(key))
                return (T) dic[key];

            return default(T);
        }

        /// <summary>
        /// Convert a Dictionary to JSON.
        /// </summary>
        /// <param name="obj">The dictionary to convert to JSON.</param>
        /// <returns>The converted dictionary in JSON string format.</returns>
        public static string toJson(this Dictionary<string, object> obj)
        {
            return MiniJson.JsonEncode(obj);
        }

        /// <summary>
        /// Convert a Dictionary to JSON.
        /// </summary>
        /// <param name="obj">The dictionary to convert to JSON.</param>
        /// <returns>The converted dictionary in JSON string format.</returns>
        public static string toJson(this Dictionary<string, string> obj)
        {
            return MiniJson.JsonEncode(obj);
        }

        /// <summary>
        /// Convert a string array to JSON.
        /// </summary>
        /// <param name="array">The string array to convert to JSON.</param>
        /// <returns>The converted dictionary in JSON string format.</returns>
        public static string toJson(this string[] array)
        {
            var list = new List<object>();
            foreach (var s in array)
                list.Add(s);

            return MiniJson.JsonEncode(list);
        }

        /// <summary>
        /// Convert string JSON into List of Objects.
        /// </summary>
        /// <param name="json">String JSON to convert.</param>
        /// <returns>List of Objects converted from string json.</returns>
        public static List<object> ArrayListFromJson(this string json)
        {
            return MiniJson.JsonDecode(json) as List<object>;
        }

        /// <summary>
        /// Convert string JSON into Dictionary.
        /// </summary>
        /// <param name="json">String JSON to convert.</param>
        /// <returns>Dictionary converted from string json.</returns>
        public static Dictionary<string, object> HashtableFromJson(this string json)
        {
            return MiniJson.JsonDecode(json) as Dictionary<string, object>;
        }
    }

    #endregion
    }

    /// <summary>
    /// Extension class for MiniJson to Encode and Decode JSON.
    /// </summary>
    public class MiniJson
    {
        /// <summary>
        /// Converts an object into a JSON string
        /// </summary>
        /// <param name="json">Object to convert to JSON string</param>
        /// <returns>JSON string</returns>
        public static string JsonEncode (object json)
        {
            return MiniJSON.Json.Serialize (json);
        }

        /// <summary>
        /// Converts an string into a JSON object
        /// </summary>
        /// <param name="json">String to convert to JSON object</param>
        /// <returns>JSON object</returns>
        public static object JsonDecode (string json)
        {
            return MiniJSON.Json.Deserialize (json);
        }
    }
}
