using ln.collections;
using ln.parse.tokenizer;
using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;

namespace ln.application.configuration
{
    public class ConfigurationParser
    {
        public ConfigurationContainer RootContainer { get; }

        public ConfigurationParser()
        {
            RootContainer = new ConfigurationContainer();
        }
        public ConfigurationParser(ConfigurationContainer rootContainer)
        {
            RootContainer = rootContainer;
        }

        public void Parse(String source)
        {
            Parse(configurationTokenizer.Parse(source, (token) => !(token is Token.WhiteSpaceToken)));
        }
        public void Parse(Token[] tokens)
        {
            Queue<Token> queue = new Queue<Token>(tokens);
            ParseContainer(queue, RootContainer);
        }

        private void ParseContainer(Queue<Token> queue,ConfigurationContainer container)
        {
            Token identifier;
            while (queue.Count > 0)
            {
                identifier = queue.Dequeue();
                if (identifier is Token.BracketToken && "}".Equals(identifier.Value))
                    return;
                
                if (identifier is Token.IdentifierToken)
                {
                    Token t2 = queue.Dequeue();
                    if (t2 is Token.OperatorToken && ":".Equals(t2.Value))
                    {
                        List<Object> arguments = new List<object>();
                        Token arg;
                        while (!(((arg = queue.Dequeue()) is Token.OperatorToken) && ";".Equals(arg.Value)))
                        {
                            arguments.Add(arg.NativeValue);
                        }
                        container.AddStatement(identifier.Value,arguments.ToArray());
                    } else {
                        Token key = null;
                        if (!t2.Is<Token.BracketToken>("{"))
                        {
                            key = t2;
                            t2 = queue.Dequeue();
                        }
                        if (!t2.Is<Token.BracketToken>("{"))
                        {
                            throw new FormatException(String.Format("expected '{{' at {0}", t2.TextPosition));
                        }

                        ConfigurationContainer childContainer = new ConfigurationContainer(container,identifier.Value,key.NativeValue);
                        ParseContainer(queue, childContainer);
                        // if (queue.Count == 0)
                        //     throw new FormatException(String.Format("Missing '}}'"));
                    }
                } else {
                    throw new FormatException(String.Format("unexepected token: {0}", identifier.Value));
                }

            }
        }
        




        static Tokenizer configurationTokenizer;

        static ConfigurationParser() {
            configurationTokenizer = Tokenizer.CreateDefaultTokenizer();

        }
    }
}