namespace etoy
{
    class KsonObject
    {
        string _kson;

        Dictionary<int, string> _stringValues;
        Dictionary<int, KsonObject> _objects;
        Dictionary<int, List<KsonObject>> _arrayObjects;
        List<string> _tempValues;
        bool _is_object;
        bool _is_array;
        int _field_count;

        public Dictionary<int, string> StringValues => _stringValues;
        public Dictionary<int, KsonObject> KsonObjects => _objects;
        public Dictionary<int, List<KsonObject>> ArrayObjects => _arrayObjects;
        public string RawKson => _kson;

        public bool IsObject => _is_object;
        public bool IsArray => _is_array;

        public int FieldCount => _field_count;


        public KsonObject(string kson)
        {
            _kson = kson;
            _stringValues = new Dictionary<int, string>();
            _objects = new Dictionary<int, KsonObject>();
            _arrayObjects = new Dictionary<int, List<KsonObject>>();
            _tempValues = new List<string>();

            _is_object = _kson[0] == '{' && _kson[^1] == '}';
            _is_array = _kson[0] == '[' && _kson[^1] == ']';

            ParseValues(this);

            _tempValues.Clear();
        }


        void ParseValues(KsonObject obj)
        {
            var values = GetStringValues(obj._kson);

            _field_count = values.Length;

            for (int i = 0, length = values.Length; i < length; i++)
            {
                var value = values[i];

                bool is_object = value[0] == '{' && value[^1] == '}';
                bool is_array = value[0] == '[' && value[^1] == ']';

                if (is_object)
                {
                    if (obj._is_array)
                    {
                        if (!obj._arrayObjects.TryGetValue(i, out var collection))
                        {
                            collection = new List<KsonObject>();
                            obj._arrayObjects[i] = collection;
                        }

                        collection.Add(new KsonObject(value));
                    }

                    if (obj.IsObject)
                        obj._objects.Add(i, new KsonObject(value));
                }
                else if (is_array)
                {
                    var objValues = GetStringValues(value);

                    List<KsonObject> list = new List<KsonObject>();
                    foreach (var objValue in objValues)
                        list.Add(new KsonObject(objValue));

                    if (obj._is_array)
                    {
                        throw new System.Exception("不支持多维数组");
                    }
                    if (obj._is_object) obj._arrayObjects.Add(i, list);
                }
                else
                {
                    obj._stringValues.Add(i, value);
                }
            }
        }


        string[] GetStringValues(string kson)
        {
            if (string.IsNullOrEmpty(kson))
                return new string[] { };

            if (kson.Length > 1)
                kson = kson[1..(kson.Length - 1)];

            _tempValues.Clear();

            int right, left = 0, indent = 0;
            for (int i = 0, length = kson.Length; i < length; i++)
            {
                char c = kson[i];

                if (c == '{' || c == '[')
                    indent++;
                if (c == '}' || c == ']')
                    indent--;

                if (indent != 0)
                    continue;

                if (c == ',')
                {
                    right = i;

                    string value = kson[left..right];
                    _tempValues.Add(value);

                    left = i + 1;
                }

                if (i == length - 1)
                {
                    string value = kson[left..length];
                    _tempValues.Add(value);
                }
            }
            return _tempValues.ToArray();
        }
    }
}