/*
 * Copyright (C) 2007-2012 Xagasoft, All rights reserved.
 *
 * This file is part of the libgats library and is released under the
 * terms of the license contained in the file LICENSE.
 */

using System.Text;
using System.IO;
using System.Linq;
using System.Collections;
using System.Collections.Generic;

namespace Com.Xagasoft.Gats
{
    /// <summary>
    /// Encapsulates a single dictionary of GatsObjects.
    /// </summary>
    /// <remarks>
    /// All keys are strings, and are encoded UTF-8.  At the moment it is
    /// advisable to stick to 7-bit ASCII or LATIN-1 compatible strings for
    /// interoperability.  If you want full unicode for keys, be sure you
    /// handle it correctly with all libraries.
    ///
    /// Values can be any valid GatsObject.
    ///
    /// Just like dictionaries in memory, order is not important and is
    /// considered random in encoded GATS.  This means that dictionary items
    /// may be in a different order after writing them and reading them back
    /// again.  Do not rely on a specific order, if you need ordered data use
    /// a GatsList.
    ///
    /// All standard dictionary interface methods are implemented, so you can
    /// use a GatsDictionary just like the .NET standard Dictionary.
    /// </remarks>
    public class GatsDictionary : GatsObject, IDictionary<string, GatsObject>
//      ICollection<KeyValuePair<string, GatsObject>>,
//      IEnumerable<KeyValuePair<string, GatsObject>>
    {
        private Dictionary<string, GatsObject> Value =
            new Dictionary<string, GatsObject>();

        public GatsDictionary()
        {
        }

        public override string ToString()
        {
            StringBuilder bld = new StringBuilder();
            bld.Append("{");
            bool begin = true;
            foreach( KeyValuePair<string, GatsObject> j in Value )
            {
                if( begin )
                    begin = false;
                else
                    bld.Append(", ");
                bld.Append( j.Key );
                bld.Append(" = ");
                bld.Append( j.Value );
            }
            bld.Append("}");
            return bld.ToString();
        }

        public override void Read( Stream s, char type )
        {
            for(;;)
            {
                GatsObject key = GatsObject.Read( s );
                if( key == null )
                    break;
                if( key.GetType() != typeof(GatsString) )
                    throw new GatsException( GatsException.Type.InvalidFormat );
                Value.Add( key.ToString(), GatsObject.Read( s ) );
            }
        }

        public override void Write( Stream s )
        {
            s.WriteByte( (int)'d' );
            foreach( KeyValuePair<string, GatsObject> j in Value )
            {
                new GatsString( j.Key ).Write( s );
                j.Value.Write( s );
            }
            s.WriteByte( (int)'e' );
        }

        //
        // Extra helper functions for making life with GATS easier
        //

        /// <summary>
        /// Helper function to add a new GatsString to the dictionary from a
        /// byte array.
        /// </summary>
        /// <param name="key">The key to insert the new value with</param>
        /// <param name="val">The byte array to be inserted as a string</param>
        public void Add( string key, byte[] val )
        {
            Add( key, new GatsString( val ) );
        }

        /// <summary>
        /// Helper function to add a new GatsString to the dictionary from a
        /// string.
        /// </summary>
        /// <remarks>
        /// The string is encoded UTF-8 by .NETs internal facilities.
        /// </remarks>
        /// <param name="key">The key to insert the new value with</param>
        /// <param name="val">The string to be inserted as a string</param>
        public void Add( string key, string val )
        {
            Add( key, new GatsString( val ) );
        }

        /// <summary>
        /// Helper function to add a new GatsInteger to the dictionary.
        /// </summary>
        /// <remarks>
        /// Implicit upcasting should allow all integer types (byte, short,
        /// int, long), and automatic unboxing should allow all object variants
        /// to be passed into this method without problem.
        /// </remarks>
        /// <param name="key">The key to insert the new value with</param>
        /// <param name="val">The long to be inserted</param>
        public void Add( string key, long val )
        {
            Add( key, new GatsInteger( val ) );
        }

        /// <summary>
        /// Helper function to add a new GatsFloat to the dictionary.
        /// </summary>
        /// <remarks>
        /// Implicit upcasting should allow floats and doubles to both be
        /// accepted by this method.  Please note that decimal types are not
        /// strictly compatible, please see GatsFloat for more details.
        /// </remarks>
        /// <param name="key">The key to insert the new value with</param>
        /// <param name="val">The double to be inserted</param>
        public void Add( string key, double val )
        {
            Add( key, new GatsFloat( val ) );
        }

        /// <summary>
        /// Helper function to add a new GatsBoolean to the dictionary.
        /// </summary>
        /// <param name="key">The key to insert the new value with</param>
        /// <param name="val">The boolean value to be inserted</param>
        public void Add( string key, bool val )
        {
            Add( key, new GatsBoolean( val ) );
        }

        /// <summary>
        /// Helper function to add a new GatsNull to the dictionary.
        /// </summary>
        /// <param name="key">The key to insert the new null value with</param>
        public void AddNull( string key )
        {
            Add( key, new GatsNull() );
        }

        /// <summary>
        /// Helper function to add a new GatsDictionary to the dictionary.
        /// </summary>
        /// <remarks>
        /// A new GatsDictionary is created, added to the dictionary, and
        /// returned.
        /// </remarks>
        /// <param name="key">The key to insert the new value with</param>
        /// <returns>A new, empty dictionary that is already added</returns>
        public GatsDictionary AddDict( string key )
        {
            GatsDictionary dict = new GatsDictionary();
            Add( key, dict );
            return dict;
        }

        /// <summary>
        /// Helper function to add a new GatsList to the dictionary.
        /// </summary>
        /// <remarks>
        /// A new GatsList is created, added to the dictionary, and returned.
        /// </remarks>
        /// <param name="key">The key to insert the new value with</param>
        /// <returns>A new, empty list that is already added</returns>
        public GatsList AddList( string key )
        {
            GatsList list = new GatsList();
            Add( key, list );
            return list;
        }

        //
        // List interface overrides under here.
        //
        public void Add( string key, GatsObject obj )
        {
            Value.Add( key, obj );
        }

        public bool Remove( string key )
        {
            return Value.Remove( key );
        }

        public bool ContainsKey( string key )
        {
            return Value.ContainsKey( key );
        }

        public bool TryGetValue( string key, out GatsObject obj )
        {
            return Value.TryGetValue( key, out obj );
        }

        public GatsObject this[string key]
        {
            get { return this.Value[key]; }
            set { this.Value[key] = value; }
        }
        
        public ICollection<string> Keys
        {
            get { return this.Value.Keys; }
        }

        public ICollection<GatsObject> Values
        {
            get { return this.Value.Values; }
        }

        public int Count
        {
            get { return this.Value.Count; }
        }

        public bool IsReadOnly
        {
            get { return false; } // return this.Value.IsReadOnly; }
        }

        public void Add( KeyValuePair<string,GatsObject> pair )
        {
            ((IDictionary<string,GatsObject>)Value).Add( pair );
        }

        public void Clear()
        {
            Value.Clear();
        }

        public bool Contains( KeyValuePair<string,GatsObject> pair )
        {
            return ((IDictionary<string,GatsObject>)Value).Contains( pair );
        }

        public void CopyTo( KeyValuePair<string,GatsObject>[] result,
                int count )
        {
            ((IDictionary<string,GatsObject>)Value).CopyTo( result, count );
        }
        
        public bool Remove( KeyValuePair<string,GatsObject> pair )
        {
            return ((IDictionary<string,GatsObject>)Value).Remove( pair );
        }

        IEnumerator<KeyValuePair<string,GatsObject> > IEnumerable<KeyValuePair<string,GatsObject> >.GetEnumerator()
        {
            return Value.GetEnumerator();
        }

        IEnumerator IEnumerable.GetEnumerator()
        {
            return Value.GetEnumerator();
        }
    }
}