// Copyright (c) Rotorz Limited. All rights reserved.
// Licensed under the MIT license. See LICENSE file in the project root.

using System;
using System.ComponentModel;
using UnityEngine;

namespace HutongGames.Rotorz.ReorderableList {

	/// <summary>
	/// Arguments which are passed to <see cref="AddMenuClickedEventHandler"/>.
	/// </summary>
	public sealed class AddMenuClickedEventArgs : EventArgs {

		/// <summary>
		/// Gets adaptor to reorderable list container.
		/// </summary>
		public IReorderableListAdaptor Adaptor { get; private set; }
		/// <summary>
		/// Gets position of the add menu button.
		/// </summary>
		public Rect ButtonPosition { get; internal set; }

		/// <summary>
		/// Initializes a new instance of <see cref="ItemMovedEventArgs"/>.
		/// </summary>
		/// <param name="adaptor">Reorderable list adaptor.</param>
		/// <param name="buttonPosition">Position of the add menu button.</param>
		public AddMenuClickedEventArgs(IReorderableListAdaptor adaptor, Rect buttonPosition) {
			this.Adaptor = adaptor;
			this.ButtonPosition = buttonPosition;
		}

	}

	/// <summary>
	/// An event handler which is invoked when the "Add Menu" button is clicked.
	/// </summary>
	/// <param name="sender">Object which raised event.</param>
	/// <param name="args">Event arguments.</param>
	public delegate void AddMenuClickedEventHandler(object sender, AddMenuClickedEventArgs args);

	/// <summary>
	/// Arguments which are passed to <see cref="ItemInsertedEventHandler"/>.
	/// </summary>
	public sealed class ItemInsertedEventArgs : EventArgs {

		/// <summary>
		/// Gets adaptor to reorderable list container which contains element.
		/// </summary>
		public IReorderableListAdaptor Adaptor { get; private set; }
		/// <summary>
		/// Gets zero-based index of item which was inserted.
		/// </summary>
		public int ItemIndex { get; private set; }

		/// <summary>
		/// Indicates if inserted item was duplicated from another item.
		/// </summary>
		public bool WasDuplicated { get; private set; }

		/// <summary>
		/// Initializes a new instance of <see cref="ItemInsertedEventArgs"/>.
		/// </summary>
		/// <param name="adaptor">Reorderable list adaptor.</param>
		/// <param name="itemIndex">Zero-based index of item.</param>
		/// <param name="wasDuplicated">Indicates if inserted item was duplicated from another item.</param>
		public ItemInsertedEventArgs(IReorderableListAdaptor adaptor, int itemIndex, bool wasDuplicated) {
			this.Adaptor = adaptor;
			this.ItemIndex = itemIndex;
			this.WasDuplicated = wasDuplicated;
		}

	}

	/// <summary>
	/// An event handler which is invoked after new list item is inserted.
	/// </summary>
	/// <param name="sender">Object which raised event.</param>
	/// <param name="args">Event arguments.</param>
	public delegate void ItemInsertedEventHandler(object sender, ItemInsertedEventArgs args);

	/// <summary>
	/// Arguments which are passed to <see cref="ItemRemovingEventHandler"/>.
	/// </summary>
	public sealed class ItemRemovingEventArgs : CancelEventArgs {

		/// <summary>
		/// Gets adaptor to reorderable list container which contains element.
		/// </summary>
		public IReorderableListAdaptor Adaptor { get; private set; }
		/// <summary>
		/// Gets zero-based index of item which is being removed.
		/// </summary>
		public int ItemIndex { get; internal set; }

		/// <summary>
		/// Initializes a new instance of <see cref="ItemRemovingEventArgs"/>.
		/// </summary>
		/// <param name="adaptor">Reorderable list adaptor.</param>
		/// <param name="itemIndex">Zero-based index of item.</param>
		public ItemRemovingEventArgs(IReorderableListAdaptor adaptor, int itemIndex) {
			this.Adaptor = adaptor;
			this.ItemIndex = itemIndex;
		}

	}

	/// <summary>
	/// An event handler which is invoked before a list item is removed.
	/// </summary>
	/// <remarks>
	/// <para>Item removal can be cancelled by setting <see cref="CancelEventArgs.Cancel"/>
	/// to <c>true</c>.</para>
	/// </remarks>
	/// <param name="sender">Object which raised event.</param>
	/// <param name="args">Event arguments.</param>
	public delegate void ItemRemovingEventHandler(object sender, ItemRemovingEventArgs args);

	/// <summary>
	/// Arguments which are passed to <see cref="ItemMovingEventHandler"/>.
	/// </summary>
	public sealed class ItemMovingEventArgs : CancelEventArgs {

		/// <summary>
		/// Gets adaptor to reorderable list container which contains element.
		/// </summary>
		public IReorderableListAdaptor Adaptor { get; private set; }
		/// <summary>
		/// Gets current zero-based index of item which is going to be moved.
		/// </summary>
		public int ItemIndex { get; internal set; }
		/// <summary>
		/// Gets the new candidate zero-based index for the item.
		/// </summary>
		/// <seealso cref="NewItemIndex"/>
		public int DestinationItemIndex { get; internal set; }

		/// <summary>
		/// Gets zero-based index of item <strong>after</strong> it has been moved.
		/// </summary>
		/// <seealso cref="DestinationItemIndex"/>
		public int NewItemIndex {
			get {
				int result = DestinationItemIndex;
				if (result > ItemIndex)
					--result;
				return result;
			}
		}

		/// <summary>
		/// Initializes a new instance of <see cref="ItemMovingEventArgs"/>.
		/// </summary>
		/// <param name="adaptor">Reorderable list adaptor.</param>
		/// <param name="itemIndex">Zero-based index of item.</param>
		/// <param name="destinationItemIndex">Xero-based index of item destination.</param>
		public ItemMovingEventArgs(IReorderableListAdaptor adaptor, int itemIndex, int destinationItemIndex) {
			this.Adaptor = adaptor;
			this.ItemIndex = itemIndex;
			this.DestinationItemIndex = destinationItemIndex;
		}

	}

	/// <summary>
	/// An event handler which is invoked before a list item is moved.
	/// </summary>
	/// <remarks>
	/// <para>Moving of item can be cancelled by setting <see cref="CancelEventArgs.Cancel"/>
	/// to <c>true</c>.</para>
	/// </remarks>
	/// <param name="sender">Object which raised event.</param>
	/// <param name="args">Event arguments.</param>
	public delegate void ItemMovingEventHandler(object sender, ItemMovingEventArgs args);

	/// <summary>
	/// Arguments which are passed to <see cref="ItemMovedEventHandler"/>.
	/// </summary>
	public sealed class ItemMovedEventArgs : EventArgs {

		/// <summary>
		/// Gets adaptor to reorderable list container which contains element.
		/// </summary>
		public IReorderableListAdaptor Adaptor { get; private set; }
		/// <summary>
		/// Gets old zero-based index of the item which was moved.
		/// </summary>
		public int OldItemIndex { get; internal set; }
		/// <summary>
		/// Gets new zero-based index of the item which was moved.
		/// </summary>
		public int NewItemIndex { get; internal set; }

		/// <summary>
		/// Initializes a new instance of <see cref="ItemMovedEventArgs"/>.
		/// </summary>
		/// <param name="adaptor">Reorderable list adaptor.</param>
		/// <param name="oldItemIndex">Old zero-based index of item.</param>
		/// <param name="newItemIndex">New zero-based index of item.</param>
		public ItemMovedEventArgs(IReorderableListAdaptor adaptor, int oldItemIndex, int newItemIndex) {
			this.Adaptor = adaptor;
			this.OldItemIndex = oldItemIndex;
			this.NewItemIndex = newItemIndex;
		}

	}

	/// <summary>
	/// An event handler which is invoked after a list item is moved.
	/// </summary>
	/// <param name="sender">Object which raised event.</param>
	/// <param name="args">Event arguments.</param>
	public delegate void ItemMovedEventHandler(object sender, ItemMovedEventArgs args);

}
