//
// BodyPartBasic.cs
//
// Author: Jeffrey Stedfast <jestedfa@microsoft.com>
//
// Copyright (c) 2013-2020 .NET Foundation and Contributors
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
//

using System;
using System.Text;

using MimeKit;

namespace MailKit {
	/// <summary>
	/// A basic message body part.
	/// </summary>
	/// <remarks>
	/// Represents any message body part that is not a multipart,
	/// message/rfc822 part, or a text part.
	/// </remarks>
	/// <example>
	/// <code language="c#" source="Examples\ImapExamples.cs" region="DownloadBodyParts"/>
	/// </example>
	public class BodyPartBasic : BodyPart
	{
		/// <summary>
		/// Initializes a new instance of the <see cref="MailKit.BodyPartBasic"/> class.
		/// </summary>
		/// <remarks>
		/// Creates a new <see cref="BodyPartBasic"/>.
		/// </remarks>
		public BodyPartBasic ()
		{
		}

		/// <summary>
		/// Gets the Content-Id of the body part, if available.
		/// </summary>
		/// <remarks>
		/// Gets the Content-Id of the body part, if available.
		/// </remarks>
		/// <value>The content identifier.</value>
		public string ContentId {
			get; set;
		}

		/// <summary>
		/// Gets the Content-Description of the body part, if available.
		/// </summary>
		/// <remarks>
		/// Gets the Content-Description of the body part, if available.
		/// </remarks>
		/// <value>The content description.</value>
		public string ContentDescription {
			get; set;
		}

		/// <summary>
		/// Gets the Content-Transfer-Encoding of the body part.
		/// </summary>
		/// <remarks>
		/// <para>Gets the Content-Transfer-Encoding of the body part.</para>
		/// <para>Hint: Use the <a href="M_MimeKit_Utils_MimeUtils_TryParse_1.htm">MimeUtils.TryParse</a>
		/// method to parse this value into a usable <see cref="MimeKit.ContentEncoding"/>.</para>
		/// </remarks>
		/// <value>The content transfer encoding.</value>
		public string ContentTransferEncoding {
			get; set;
		}

		/// <summary>
		/// Gets the size of the body part, in bytes.
		/// </summary>
		/// <remarks>
		/// Gets the size of the body part, in bytes.
		/// </remarks>
		/// <value>The number of octets.</value>
		public uint Octets {
			get; set;
		}

		/// <summary>
		/// Gets the MD5 hash of the content, if available.
		/// </summary>
		/// <remarks>
		/// Gets the MD5 hash of the content, if available.
		/// </remarks>
		/// <value>The content md5.</value>
		public string ContentMd5 {
			get; set;
		}

		/// <summary>
		/// Gets the Content-Disposition of the body part, if available.
		/// </summary>
		/// <remarks>
		/// <para>Gets the Content-Disposition of the body part, if available.</para>
		/// <note type="note">The Content-Disposition value is only retrieved if the
		/// <see cref="MessageSummaryItems.BodyStructure"/> flag is used when fetching
		/// summary information from an <see cref="IMailFolder"/>.</note>
		/// </remarks>
		/// <value>The content disposition.</value>
		public ContentDisposition ContentDisposition {
			get; set;
		}

		/// <summary>
		/// Gets the Content-Language of the body part, if available.
		/// </summary>
		/// <remarks>
		/// <para>Gets the Content-Language of the body part, if available.</para>
		/// <para>The Content-Language value is only retrieved if the
		/// <see cref="MessageSummaryItems.BodyStructure"/> flag is used when fetching
		/// summary information from an <see cref="IMailFolder"/>.</para>
		/// </remarks>
		/// <value>The content language.</value>
		public string[] ContentLanguage {
			get; set;
		}

		/// <summary>
		/// Gets the Content-Location of the body part, if available.
		/// </summary>
		/// <remarks>
		/// <para>Gets the Content-Location of the body part, if available.</para>
		/// <para>The Content-Location value is only retrieved if the
		/// <see cref="MessageSummaryItems.BodyStructure"/> flag is used when fetching
		/// summary information from an <see cref="IMailFolder"/>.</para>
		/// </remarks>
		/// <value>The content location.</value>
		public Uri ContentLocation {
			get; set;
		}

		/// <summary>
		/// Determines whether or not the body part is an attachment.
		/// </summary>
		/// <remarks>
		/// <para>Determines whether or not the body part is an attachment based on the value of
		/// the Content-Disposition.</para>
		/// <note type="note">Since the value of the Content-Disposition header is needed, it
		/// is necessary to include the <see cref="MessageSummaryItems.BodyStructure"/> flag when
		/// fetching summary information from an <see cref="IMailFolder"/>.</note>
		/// </remarks>
		/// <value><c>true</c> if this part is an attachment; otherwise, <c>false</c>.</value>
		public bool IsAttachment {
			get { return ContentDisposition != null && ContentDisposition.IsAttachment; }
		}

		/// <summary>
		/// Get the name of the file.
		/// </summary>
		/// <remarks>
		/// <para>First checks for the "filename" parameter on the Content-Disposition header. If
		/// that does not exist, then the "name" parameter on the Content-Type header is used.</para>
		/// <note type="note">Since the value of the Content-Disposition header is needed, it is
		/// necessary to include the <see cref="MessageSummaryItems.BodyStructure"/> flag when
		/// fetching summary information from an <see cref="IMailFolder"/>.</note>
		/// </remarks>
		/// <value>The name of the file.</value>
		public string FileName {
			get {
				string filename = null;

				if (ContentDisposition != null)
					filename = ContentDisposition.FileName;

				if (filename == null)
					filename = ContentType.Name;

				return filename != null ? filename.Trim () : null;
			}
		}

		/// <summary>
		/// Dispatches to the specific visit method for this MIME body part.
		/// </summary>
		/// <remarks>
		/// This default implementation for <see cref="MailKit.BodyPart"/> nodes
		/// calls <see cref="MailKit.BodyPartVisitor.VisitBodyPart"/>. Override this
		/// method to call into a more specific method on a derived visitor class
		/// of the <see cref="MailKit.BodyPartVisitor"/> class. However, it should still
		/// support unknown visitors by calling
		/// <see cref="MailKit.BodyPartVisitor.VisitBodyPart"/>.
		/// </remarks>
		/// <param name="visitor">The visitor.</param>
		/// <exception cref="System.ArgumentNullException">
		/// <paramref name="visitor"/> is <c>null</c>.
		/// </exception>
		public override void Accept (BodyPartVisitor visitor)
		{
			if (visitor == null)
				throw new ArgumentNullException (nameof (visitor));

			visitor.VisitBodyPartBasic (this);
		}

		/// <summary>
		/// Encodes the <see cref="BodyPart"/> into the <see cref="System.Text.StringBuilder"/>.
		/// </summary>
		/// <remarks>
		/// Encodes the <see cref="BodyPart"/> into the <see cref="System.Text.StringBuilder"/>.
		/// </remarks>
		/// <param name="builder">The string builder.</param>
		protected override void Encode (StringBuilder builder)
		{
			Encode (builder, ContentType);
			builder.Append (' ');
			Encode (builder, ContentId);
			builder.Append (' ');
			Encode (builder, ContentDescription);
			builder.Append (' ');
			Encode (builder, ContentTransferEncoding);
			builder.Append (' ');
			Encode (builder, Octets);
			builder.Append (' ');
			Encode (builder, ContentMd5);
			builder.Append (' ');
			Encode (builder, ContentDisposition);
			builder.Append (' ');
			Encode (builder, ContentLanguage);
			builder.Append (' ');
			Encode (builder, ContentLocation);
		}
	}
}