//
//  ToolbarWrapper.cs
//
//  Author:
//       toadicus <>
//
//  Copyright (c) 2013 toadicus
//
//  This program is free software: you can redistribute it and/or modify
//  it under the terms of the GNU General Public License as published by
//  the Free Software Foundation, either version 3 of the License, or
//  (at your option) any later version.
//
//  This program is distributed in the hope that it will be useful,
//  but WITHOUT ANY WARRANTY; without even the implied warranty of
//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//  GNU General Public License for more details.
//
//  You should have received a copy of the GNU General Public License
//  along with this program.  If not, see <http://www.gnu.org/licenses/>.
using System;
using System.Linq;
using System.Reflection;
using UnityEngine;

namespace VOID
{
	/// <summary>
	/// Wraps a Toolbar clickable button, after fetching it from a foreign assembly.
	/// </summary>
	internal class ToolbarButtonWrapper
	{
		protected static System.Type ToolbarManager;
		protected static object TBManagerInstance;
		protected static MethodInfo TBManagerAdd;

		/// <summary>
		/// Wraps the ToolbarManager class, if present.
		/// </summary>
		/// <returns><c>true</c>, if ToolbarManager is wrapped, <c>false</c> otherwise.</returns>
		protected static bool TryWrapToolbarManager()
		{
			if (ToolbarManager == null)
			{
				Tools.PostDebugMessage(string.Format(
					"{0}: Loading ToolbarManager.",
					"ToolbarButtonWrapper"
					));

				ToolbarManager = AssemblyLoader.loadedAssemblies
					.Select(a => a.assembly.GetExportedTypes())
						.SelectMany(t => t)
						.FirstOrDefault(t => t.FullName == "Toolbar.ToolbarManager");

				Tools.PostDebugMessage(string.Format(
					"{0}: Loaded ToolbarManager.  Getting Instance.",
					"ToolbarButtonWrapper"
					));

				if (ToolbarManager == null)
				{
					return false;
				}

				TBManagerInstance = ToolbarManager.GetProperty(
					"Instance",
					System.Reflection.BindingFlags.Public | System.Reflection.BindingFlags.Static
					)
					.GetValue(null, null);

				Tools.PostDebugMessage(string.Format(
					"{0}: Got ToolbarManager Instance '{1}'.  Getting 'add' method.",
					"ToolbarButtonWrapper",
					TBManagerInstance
					));

				TBManagerAdd = ToolbarManager.GetMethod("add");

				Tools.PostDebugMessage(string.Format(
					"{0}: Got ToolbarManager Instance 'add' method.  Loading IButton.",
					"ToolbarButtonWrapper"
					));
			}

			return true;
		}

		/// <summary>
		/// Gets a value indicating whether <see cref="Toolbar.ToolbarManager"/> is present.
		/// </summary>
		/// <value><c>true</c>, if ToolbarManager is wrapped, <c>false</c> otherwise.</value>
		public static bool ToolbarManagerPresent
		{
			get
			{
				return TryWrapToolbarManager();
			}
		}

		/// <summary>
		/// If ToolbarManager is present, initializes a new instance of the <see cref="VOID.ToolbarButtonWrapper"/> class.
		/// </summary>
		/// <param name="ns">Namespace, usually the plugin name.</param>
		/// <param name="id">Identifier, unique per namespace.</param>
		/// <returns>If ToolbarManager is present, a new <see cref="Toolbar.IButton"/> object, <c>null</c> otherwise.</returns>
		public static ToolbarButtonWrapper TryWrapToolbarButton(string ns, string id)
		{
			if (ToolbarManagerPresent)
			{
				object button = TBManagerAdd.Invoke(TBManagerInstance, new object[] { ns, id });

				Tools.PostDebugMessage(string.Format(
					"{0}: Added Button '{1}' with ToolbarManager.  Getting 'Text' property",
					"ToolbarButtonWrapper",
					button.ToString()
				));

				return new ToolbarButtonWrapper(button);
			}
			else
			{
				return null;
			}
		}

		protected System.Type IButton;
		protected object Button;
		protected PropertyInfo ButtonText;
		protected PropertyInfo ButtonTextColor;
		protected PropertyInfo ButtonTexturePath;
		protected PropertyInfo ButtonToolTip;
		protected PropertyInfo ButtonVisible;
		protected PropertyInfo ButtonVisibility;
		protected PropertyInfo ButtonEnalbed;
		protected PropertyInfo ButtonImportant;
		protected EventInfo ButtonOnClick;
		protected EventInfo ButtonOnMouseEnter;
		protected EventInfo ButtonOnMouseLeave;
		protected MethodInfo ButtonDestroy;
		protected System.Type GameScenesVisibilityType;

		/// <summary>
		/// The text displayed on the button. Set to null to hide text.
		/// </summary>
		/// <remarks>
		/// The text can be changed at any time to modify the button's appearance. Note that since this will also
		/// modify the button's size, this feature should be used sparingly, if at all.
		/// </remarks>
		/// <seealso cref="TexturePath"/>
		public string Text
		{
			get
			{
				return this.ButtonText.GetValue(this.Button, null) as String;
			}
			set
			{
				this.ButtonText.SetValue(this.Button, value, null);
			}
		}

		/// <summary>
		/// The color the button text is displayed with. Defaults to Color.white.
		/// </summary>
		/// <remarks>
		/// The text color can be changed at any time to modify the button's appearance.
		/// </remarks>
		public Color TextColor
		{
			get
			{
				return (Color)this.ButtonTextColor.GetValue(this.Button, null);
			}
			set
			{
				this.ButtonTextColor.SetValue(this.Button, value, null);
			}
		}

		/// <summary>
		/// The path of a texture file to display an icon on the button. Set to null to hide icon.
		/// </summary>
		/// <remarks>
		/// <para>
		/// A texture path on a button will have precedence over text. That is, if both text and texture path
		/// have been set on a button, the button will show the texture, not the text.
		/// </para>
		/// <para>
		/// The texture size must not exceed 24x24 pixels.
		/// </para>
		/// <para>
		/// The texture path must be relative to the "GameData" directory, and must not specify a file name suffix.
		/// Valid example: MyAddon/Textures/icon_mybutton
		/// </para>
		/// <para>
		/// The texture path can be changed at any time to modify the button's appearance.
		/// </para>
		/// </remarks>
		/// <seealso cref="Text"/>
		public string TexturePath
		{
			get
			{
				return this.ButtonTexturePath.GetValue(this.Button, null) as string;
			}
			set
			{
				this.ButtonTexturePath.SetValue(this.Button, value, null);
			}
		}

		/// <summary>
		/// The button's tool tip text. Set to null if no tool tip is desired.
		/// </summary>
		/// <remarks>
		/// Tool Tip Text Should Always Use Headline Style Like This.
		/// </remarks>
		public string ToolTip
		{
			get
			{
				return this.ButtonToolTip.GetValue(this.Button, null) as string;
			}
			set
			{
				this.ButtonToolTip.SetValue(this.Button, value, null);
			}
		}

		/// <summary>
		/// Whether this button is currently visible or not. Can be used in addition to or as a replacement for <see cref="Visibility"/>.
		/// </summary>
		public bool Visible
		{
			get
			{
				return (bool)this.ButtonVisible.GetValue(this.Button, null);
			}
			set
			{
				this.ButtonVisible.SetValue(this.Button, value, null);
			}
		}

		/// <summary>
		/// Whether this button is currently enabled (clickable) or not. This will not affect the player's ability to
		/// position the button on their screen.
		/// </summary>
		public bool Enabled
		{
			get
			{
				return (bool)this.ButtonEnalbed.GetValue(this.Button, null);
			}
			set
			{
				this.ButtonEnalbed.SetValue(this.Button, value, null);
			}
		}

		/// <summary>
		/// Whether this button is currently "important."  Set to false to return to normal button behaviour.
		/// </summary>
		/// <remarks>
		/// <para>
		/// This can be used to temporarily force the button to be shown on the screen regardless of the toolbar being
		/// currently in auto-hidden mode.  For example, a button that signals the arrival of a private message in a
		/// chat room could mark itself as "important" as long as the message has not been read.
		/// </para>
		/// <para>
		/// Setting this property does not change the appearance of the button.  use <see cref="TexturePath"/>  to
		/// change the button's icon.
		/// </para>
		/// <para>
		/// This feature should be used only sparingly, if at all, since it forces the button to be displayed on screen
		/// even when it normally wouldn't.
		/// </para>
		/// </remarks>
		/// <value><c>true</c> if important; otherwise, <c>false</c>.</value>
		public bool Important
		{
			get
			{
				return (bool)this.ButtonImportant.GetValue(this.Button, null);
			}
			set
			{
				this.ButtonImportant.SetValue(this.Button, value, null);
			}
		}

		private ToolbarButtonWrapper()
		{
		}

		/// <summary>
		/// Initializes a new instance of the <see cref="VOID.ToolbarButtonWrapper"/> class.
		/// </summary>
		/// <param name="ns">Namespace, usually the plugin name.</param>
		/// <param name="id">Identifier, unique per namespace.</param>
		protected ToolbarButtonWrapper(object button)
		{
			this.Button = button;

			this.IButton = AssemblyLoader.loadedAssemblies
				.Select(a => a.assembly.GetExportedTypes())
				.SelectMany(t => t)
				.FirstOrDefault(t => t.FullName == "Toolbar.IButton");

			Tools.PostDebugMessage(string.Format(
				"{0}: Loaded IButton.  Adding Button with ToolbarManager.",
				this.GetType().Name
			));

			this.ButtonText = this.IButton.GetProperty("Text");

			Tools.PostDebugMessage(string.Format(
				"{0}: Got 'Text' property.  Getting 'TextColor' property.",
				this.GetType().Name
			));

			this.ButtonTextColor = this.IButton.GetProperty("TextColor");

			Tools.PostDebugMessage(string.Format(
				"{0}: Got 'TextColor' property.  Getting 'TexturePath' property.",
				this.GetType().Name
			));

			this.ButtonTexturePath = this.IButton.GetProperty("TexturePath");
			
			Tools.PostDebugMessage(string.Format(
				"{0}: Got 'TexturePath' property.  Getting 'ToolTip' property.",
				this.GetType().Name
			));

			this.ButtonToolTip = this.IButton.GetProperty("ToolTip");

			Tools.PostDebugMessage(string.Format(
				"{0}: Got 'ToolTip' property.  Getting 'Visible' property.",
				this.GetType().Name
			));

			this.ButtonVisible = this.IButton.GetProperty("Visible");

			Tools.PostDebugMessage(string.Format(
				"{0}: Got 'Visible' property.  Getting 'Visibility' property.",
				this.GetType().Name
			));

			this.ButtonVisibility = this.IButton.GetProperty("Visibility");

			Tools.PostDebugMessage(string.Format(
				"{0}: Got 'Visibility' property.  Getting 'Enabled' property.",
				this.GetType().Name
			));

			this.ButtonEnalbed = this.IButton.GetProperty("Enabled");

			Tools.PostDebugMessage(string.Format(
				"{0}: Got 'Enabled' property.  Getting 'OnClick' event.",
				this.GetType().Name
			));

			this.ButtonImportant = this.IButton.GetProperty("Important");

			Tools.PostDebugMessage(string.Format(
				"{0}: Got 'Enabled' property.  Getting 'OnClick' event.",
				this.GetType().Name
			));

			this.ButtonOnClick = this.IButton.GetEvent("OnClick");

			Tools.PostDebugMessage(string.Format(
				"{0}: Got 'OnClick' event '{1}'.  Getting 'OnMouseEnter' event.",
				this.GetType().Name,
				this.ButtonOnClick.ToString()
			));

			this.ButtonOnMouseEnter = this.IButton.GetEvent("OnMouseEnter");

			Tools.PostDebugMessage(string.Format(
				"{0}: Got 'OnMouseEnter' event '{1}'.  Getting 'OnMouseLeave' event.",
				this.GetType().Name,
				this.ButtonOnClick.ToString()
				));

			this.ButtonOnMouseLeave = this.IButton.GetEvent("OnMouseLeave");

			Tools.PostDebugMessage(string.Format(
				"{0}: Got 'OnMouseLeave' event '{1}'.  Getting 'Destroy' method.",
				this.GetType().Name,
				this.ButtonOnClick.ToString()
				));

			this.ButtonDestroy = this.IButton.GetMethod("Destroy");

			Tools.PostDebugMessage(string.Format(
				"{0}: Got 'Destroy' property '{1}'.  Loading GameScenesVisibility class.",
				this.GetType().Name,
				this.ButtonDestroy.ToString()
			));

			this.GameScenesVisibilityType = AssemblyLoader.loadedAssemblies
				.Select(a => a.assembly.GetExportedTypes())
					.SelectMany(t => t)
					.FirstOrDefault(t => t.FullName == "Toolbar.GameScenesVisibility");

			Tools.PostDebugMessage(string.Format(
				"{0}: Got 'GameScenesVisibility' class '{1}'.",
				this.GetType().Name,
				this.GameScenesVisibilityType.ToString()
			));

			Tools.PostDebugMessage("ToolbarButtonWrapper built!");
		}

		/// <summary>
		/// Adds event handler to receive "on click" events.
		/// </summary>
		/// <example>
		/// <code>
		/// ToolbarButtonWrapper button = ...
		/// button.AddButtonClickHandler(
		/// 	(e) =>
		/// 	{
		/// 		Debug.Log("button clicked, mouseButton: " + e.Mousebutton");
		/// 	}
		/// );
		/// </code>
		/// </example>
		/// <param name="Handler">Delegate to handle "on click" events</param>
		public void AddButtonClickHandler(Action<object> Handler)
		{
			this.AddButtonEventHandler(this.ButtonOnClick, Handler);
		}

		/// <summary>
		/// Adds event handler that can be registered with to receive "on mouse enter" events.
		/// </summary>
		/// <example>
		/// <code>
		/// ToolbarWrapperButton button = ...
		/// button.AddButtonOnMouseEnterHandler(
		/// 	(e) =>
		/// 	{
		/// 		Debug.Log("mouse entered button");
		/// 	}
		/// );
		/// </code>
		/// </example>
		/// <param name="Handler">Delegate to handle "OnMouseEnter" events.</param>
		public void AddButtonOnMouseEnterHandler(Action<object> Handler)
		{
			this.AddButtonEventHandler(this.ButtonOnMouseEnter, Handler);
		}

		/// <summary>
		/// Adds event handler that can be registered with to receive "on mouse leave" events.
		/// </summary>
		/// <example>
		/// <code>
		/// ToolbarWrapperButton button = ...
		/// button.AddButtonOnMouseLeaveHandler(
		/// 	(e) =>
		/// 	{
		/// 		Debug.Log("mouse left button");
		/// 	}
		/// );
		/// </code>
		/// </example>
		/// <param name="Handler">Delegate to handle "OnMouseLeave" events.</param>
		public void AddButtonOnMouseLeaveHandler(Action<object> Handler)
		{
			this.AddButtonEventHandler(this.ButtonOnMouseLeave, Handler);
		}

		/// <summary>
		/// Sets this button's visibility. Can be used in addition to or as a replacement for <see cref="Visible"/>.
		/// </summary>
		/// <param name="gameScenes">Array of GameScene objects in which the button should be visible.</param>
		public void SetButtonVisibility(params GameScenes[] gameScenes)
		{
			object GameScenesVisibilityObj = Activator.CreateInstance(this.GameScenesVisibilityType, gameScenes);
			this.ButtonVisibility.SetValue(this.Button, GameScenesVisibilityObj, null);
		}

		/// <summary>
		/// Permanently destroys this button so that it is no longer displayed.
		/// Should be used when a plugin is stopped to remove leftover buttons.
		/// </summary>
		public void Destroy()
		{
			this.ButtonDestroy.Invoke(this.Button, null);
		}

		// Utility method for use with the AddButton<event>Handler API methods.
		protected void AddButtonEventHandler(EventInfo Event, Action<object> Handler)
		{
			Delegate d = Delegate.CreateDelegate(Event.EventHandlerType, Handler.Target, Handler.Method);
			MethodInfo addHandler = Event.GetAddMethod();
			addHandler.Invoke(this.Button, new object[] { d });
		}
	}
}