//  This file is part of YamlDotNet - A .NET library for YAML.
//  Copyright (c) Antoine Aubry 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.Globalization;

namespace YamlDotNet.Core.Events
{
    /// <summary>
    /// Represents a sequence start event.
    /// </summary>
    public class SequenceStart : NodeEvent
    {
        /// <summary>
        /// Gets a value indicating the variation of depth caused by this event.
        /// The value can be either -1, 0 or 1. For start events, it will be 1,
        /// for end events, it will be -1, and for the remaining events, it will be 0.
        /// </summary>
        public override int NestingIncrease
        {
            get
            {
                return 1;
            }
        }

        /// <summary>
        /// Gets the event type, which allows for simpler type comparisons.
        /// </summary>
        internal override EventType Type
        {
            get
            {
                return EventType.SequenceStart;
            }
        }

        private readonly bool isImplicit;

        /// <summary>
        /// Gets a value indicating whether this instance is implicit.
        /// </summary>
        /// <value>
        ///     <c>true</c> if this instance is implicit; otherwise, <c>false</c>.
        /// </value>
        public bool IsImplicit
        {
            get
            {
                return isImplicit;
            }
        }

        /// <summary>
        /// Gets a value indicating whether this instance is canonical.
        /// </summary>
        /// <value></value>
        public override bool IsCanonical
        {
            get
            {
                return !isImplicit;
            }
        }

        private readonly SequenceStyle style;

        /// <summary>
        /// Gets the style.
        /// </summary>
        /// <value>The style.</value>
        public SequenceStyle Style
        {
            get
            {
                return style;
            }
        }

        /// <summary>
        /// Initializes a new instance of the <see cref="SequenceStart"/> class.
        /// </summary>
        /// <param name="anchor">The anchor.</param>
        /// <param name="tag">The tag.</param>
        /// <param name="isImplicit">if set to <c>true</c> [is implicit].</param>
        /// <param name="style">The style.</param>
        /// <param name="start">The start position of the event.</param>
        /// <param name="end">The end position of the event.</param>
        public SequenceStart(string anchor, string tag, bool isImplicit, SequenceStyle style, Mark start, Mark end)
            : base(anchor, tag, start, end)
        {
            this.isImplicit = isImplicit;
            this.style = style;
        }

        /// <summary>
        /// Initializes a new instance of the <see cref="SequenceStart"/> class.
        /// </summary>
        public SequenceStart(string anchor, string tag, bool isImplicit, SequenceStyle style)
            : this(anchor, tag, isImplicit, style, Mark.Empty, Mark.Empty)
        {
        }

        /// <summary>
        /// Returns a <see cref="T:System.String"/> that represents the current <see cref="T:System.Object"/>.
        /// </summary>
        /// <returns>
        /// A <see cref="T:System.String"/> that represents the current <see cref="T:System.Object"/>.
        /// </returns>
        public override string ToString()
        {
            return string.Format(
                CultureInfo.InvariantCulture,
                "Sequence start [anchor = {0}, tag = {1}, isImplicit = {2}, style = {3}]",
                Anchor,
                Tag,
                isImplicit,
                style
            );
        }

        /// <summary>
        /// Invokes run-time type specific Visit() method of the specified visitor.
        /// </summary>
        /// <param name="visitor">visitor, may not be null.</param>
        public override void Accept(IParsingEventVisitor visitor)
        {
            visitor.Visit(this);
        }
    }
}