// ==========================================================================
// This software is subject to the provisions of the Zope Public License,
// Version 2.0 (ZPL).  A copy of the ZPL should accompany this distribution.
// THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED
// WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
// WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS
// FOR A PARTICULAR PURPOSE.
// ==========================================================================

using System;
using System.Runtime.InteropServices;

namespace Python.Runtime {

    /// 
    /// Represents a Python dictionary object. See the documentation at
    /// http://www.python.org/doc/current/api/dictObjects.html for details.
    /// 

    public class PyDict : PyObject {

	/// 
	/// PyDict Constructor
	/// 
	///
	/// 
	/// Creates a new PyDict from an existing object reference. Note 
	/// that the instance assumes ownership of the object reference. 
	/// The object reference is not checked for type-correctness. 
	/// 

	public PyDict(IntPtr ptr) : base(ptr) {}


	/// 
	/// PyDict Constructor
	/// 
	///
	/// 
	/// Creates a new Python dictionary object.
	/// 

	public PyDict() : base() {
	    obj = Runtime.PyDict_New();
	    if (obj == IntPtr.Zero) {
		throw new PythonException();
	    }
	}


	/// 
	/// PyDict Constructor
	/// 
	///
	/// 
	/// Copy constructor - obtain a PyDict from a generic PyObject. An 
	/// ArgumentException will be thrown if the given object is not a
	/// Python dictionary object.
	/// 

	public PyDict(PyObject o) : base() {
	    if (!IsDictType(o)) {
		throw new ArgumentException("object is not a dict");
	    }
	    Runtime.Incref(o.obj);
	    obj = o.obj;
	}


	/// 
	/// IsDictType Method
	/// 
	///
	/// 
	/// Returns true if the given object is a Python dictionary.
	/// 

	public static bool IsDictType(PyObject value) {
	    return Runtime.PyDict_Check(value.obj);
	}


	/// 
	/// HasKey Method
	/// 
	///
	/// 
	/// Returns true if the object key appears in the dictionary.
	/// 

	public bool HasKey(PyObject key) {
	    return (Runtime.PyMapping_HasKey(obj, key.obj) != 0);
	}


	/// 
	/// HasKey Method
	/// 
	///
	/// 
	/// Returns true if the string key appears in the dictionary.
	/// 

	public bool HasKey(string key) {
	    return HasKey(new PyString(key));
	}


	/// 
	/// Keys Method
	/// 
	///
	/// 
	/// Returns a sequence containing the keys of the dictionary.
	/// 

	public PyObject Keys() {
	    IntPtr items = Runtime.PyDict_Keys(obj);
	    if (items == IntPtr.Zero) {
		throw new PythonException();
	    }
	    return new PyObject(items);
	}


	/// 
	/// Values Method
	/// 
	///
	/// 
	/// Returns a sequence containing the values of the dictionary.
	/// 

	public PyObject Values() {
	    IntPtr items = Runtime.PyDict_Values(obj);
	    if (items == IntPtr.Zero) {
		throw new PythonException();
	    }
	    return new PyObject(items);
	}


	/// 
	/// Items Method
	/// 
	///
	/// 
	/// Returns a sequence containing the items of the dictionary.
	/// 

	public PyObject Items() {
	    IntPtr items = Runtime.PyDict_Items(obj);
	    if (items == IntPtr.Zero) {
		throw new PythonException();
	    }
	    return new PyObject(items);
	}


	/// 
	/// Copy Method
	/// 
	///
	/// 
	/// Returns a copy of the dictionary.
	/// 

	public PyDict Copy() {
	    IntPtr op = Runtime.PyDict_Copy(obj);
	    if (op == IntPtr.Zero) {
		throw new PythonException();
	    }
	    return new PyDict(op);
	}


	/// 
	/// Update Method
	/// 
	///
	/// 
	/// Update the dictionary from another dictionary.
	/// 

	public void Update(PyObject other) {
	    int result = Runtime.PyDict_Update(obj, other.obj);
	    if (result < 0) {
		throw new PythonException();
	    }
	}


	/// 
	/// Clear Method
	/// 
	///
	/// 
	/// Clears the dictionary.
	/// 

	public void Clear() {
	    Runtime.PyDict_Clear(obj);
	}


    }

}