//------------------------------------------------------------------------------
// <copyright file="Literal.cs" company="Microsoft">
//     Copyright (c) Microsoft Corporation.  All rights reserved.
// </copyright>
//------------------------------------------------------------------------------

namespace System.Web.UI.WebControls {

    using System;
    using System.ComponentModel;
    using System.Globalization;
    using System.Web;
    using System.Web.UI;

    public class LiteralControlBuilder : ControlBuilder {

        public override bool AllowWhitespaceLiterals() {
            return false;
        }

        public override void AppendLiteralString(string s) {

            // If it's just a white space string, delegate to the base
            if (Util.IsWhiteSpaceString(s)) {
                base.AppendLiteralString(s);
                return;
            }

            // Treat the inner text as if it had been set on the 'Text' attribute
            PreprocessAttribute(String.Empty /*filter*/, "text", s, false /*mainDirectiveMode*/);
        }


        public override void AppendSubBuilder(ControlBuilder subBuilder) {
            throw new HttpException(SR.GetString(SR.Control_does_not_allow_children,
                ControlType.ToString()));
        }
    }

    // The reason we define this empty override in the WebControls namespace is
    // to expose it as a control that can be used on a page (ASURT 54683)
    // E.g. <asp:literal runat=server id=lit1/>

    [
    DataBindingHandler("System.Web.UI.Design.TextDataBindingHandler, " + AssemblyRef.SystemDesign),
    DefaultProperty("Text"),
    Designer("System.Web.UI.Design.WebControls.LiteralDesigner, " + AssemblyRef.SystemDesign),
    ControlBuilderAttribute(typeof(LiteralControlBuilder)),
    ]
    public class Literal : Control, ITextControl {


        /// <devdoc>
        ///     [To be supplied.]
        /// </devdoc>
        [
        DefaultValue(LiteralMode.Transform),
        WebCategory("Behavior"),
        WebSysDescription(SR.Literal_Mode)
        ]
        public LiteralMode Mode {
            get {
                object mode = ViewState["Mode"];
                return mode == null ? LiteralMode.Transform : (LiteralMode)mode;
            }
            set {
                if ((value < LiteralMode.Transform) || (value > LiteralMode.Encode)) {
                    throw new ArgumentOutOfRangeException("value");
                }

                ViewState["Mode"] = value;
            }
        }


        /// <devdoc>
        ///     [To be supplied.]
        /// </devdoc>
        [
        Localizable(true),
        Bindable(true),
        WebCategory("Appearance"),
        DefaultValue(""),
        WebSysDescription(SR.Literal_Text),
        ]
        public string Text {
            get {
                string s = (string)ViewState["Text"];
                return (s != null) ? s : String.Empty;
            }
            set {
                ViewState["Text"] = value;
            }
        }


        /// <internalonly/>
        /// <devdoc>
        ///     [To be supplied.]
        /// </devdoc>
        protected override void AddParsedSubObject(object obj) {
            if (obj is LiteralControl) {
                Text = ((LiteralControl)obj).Text;
            }
            else {
                throw new HttpException(SR.GetString(SR.Cannot_Have_Children_Of_Type, "Literal", obj.GetType().Name.ToString(CultureInfo.InvariantCulture)));
            }
        }


        /// <devdoc>
        ///     [To be supplied.]
        /// </devdoc>
        protected override ControlCollection CreateControlCollection() {
            return new EmptyControlCollection(this);
        }


        /// <devdoc>
        /// </devdoc>
        [
        EditorBrowsable(EditorBrowsableState.Never),
        ]
        public override void Focus() {
            throw new NotSupportedException(SR.GetString(SR.NoFocusSupport, this.GetType().Name));
        }



        /// <devdoc>
        ///     [To be supplied.]
        /// </devdoc>
        protected internal override void Render(HtmlTextWriter writer) {
            string text = Text;
            if (text.Length != 0) {
                if (Mode != LiteralMode.Encode) {
                    writer.Write(text);
                    return;
                }

                HttpUtility.HtmlEncode(text, writer);
            }
        }
    }
}