//////////////////////////////////////////////////////////////////////////////
//  Project:   Ob51
//  License:   Apache License, Version 2.0; for details see LICENSE file
//  Copyright: see NOTICE file
//
//  Last file commit: $Revision: 92 $   Made by: $Author: command0 $
//////////////////////////////////////////////////////////////////////////////

using System;
using NUnit.Framework;
using ProgramNode = Ob51.Compiler.InternalTree.ProgramNode;

/// <summary>
/// A class that provides simple forms for assertions commonly used in this
/// test DLL.
/// </summary>
internal static class ProgramNodeAssert
{
    private static string MakeName(ProgramNode node)
    {
        return node.GetType().ToString() + " " + node.Name;
    }

    internal static void ChildrenCountEquals(int expected, ProgramNode node)
    {
        Assert.AreEqual(expected, node.ChildrenCount,
            MakeName(node) + " node has wrong number of children");
    }

    internal static void NameEquals(string expected, ProgramNode node)
    {
        Assert.AreEqual(expected, node.Name,
            MakeName(node) + " node has wrong Name property value");
    }

    internal static void TypeEquals(int expected, ProgramNode node)
    {
        Assert.AreEqual(expected, node.Type,
            MakeName(node) + " node has wrong Type property value");
    }

    internal static void PropertiesEqual(int ChildrenCount,
                                         int Type,
                                         string Name,
                                         ProgramNode node)
    {
        NameEquals(Name, node);
        TypeEquals(Type, node);
        ChildrenCountEquals(ChildrenCount, node);
    }

    internal static void SameChildByNameAndIndex(int index,
                                                 string name,
                                                 ProgramNode father)
    {
        Assert.AreSame(father[index], father[name],
            MakeName(father) + " node children with index " + index +
                " and name " + name + " are not same");
    }

    /// <summary>
    /// Checks whether the child number <paramref name="childNumber"/> of node
    /// <paramref name="father"/> can be casted to <typeparamref name="T"/> type.
    /// If it can, the result of casting is returned. Otherwise an exception is thrown.
    /// </summary>
    internal static T CastChildToType<T>(ProgramNode father,
                                               int childNumber) 
        where T : ProgramNode
    {
        Assert.IsInstanceOfType(typeof(T), father[childNumber],
            childNumber.ToString() + " son of " + father.GetType().ToString());
        return (T)father[childNumber];
    }
}