/******************************************************************************
 * Spine Runtimes Software License v2.5
 *
 * Copyright (c) 2013-2016, Esoteric Software
 * All rights reserved.
 *
 * You are granted a perpetual, non-exclusive, non-sublicensable, and
 * non-transferable license to use, install, execute, and perform the Spine
 * Runtimes software and derivative works solely for personal or internal
 * use. Without the written permission of Esoteric Software (see Section 2 of
 * the Spine Software License Agreement), you may not (a) modify, translate,
 * adapt, or develop new applications using the Spine Runtimes or otherwise
 * create derivative works or improvements of the Spine Runtimes or (b) remove,
 * delete, alter, or obscure any trademarks or any copyright, trademark, patent,
 * or other intellectual property or proprietary rights notices on or in the
 * Software, including any copy thereof. Redistributions in binary or source
 * form must include this license and terms.
 *
 * THIS SOFTWARE IS PROVIDED BY ESOTERIC SOFTWARE "AS IS" AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
 * EVENT SHALL ESOTERIC SOFTWARE BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, BUSINESS INTERRUPTION, OR LOSS OF
 * USE, DATA, OR PROFITS) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *****************************************************************************/

using UnityEngine;
using System.Collections;
using Spine;

namespace Spine.Unity {
	/// <summary>
	/// Use this as a condition-blocking yield instruction for Unity Coroutines. 
	/// The routine will pause until the AnimationState fires an event matching the given event name or EventData reference.</summary>
	public class WaitForSpineEvent : IEnumerator {

		Spine.EventData m_TargetEvent;
		string m_EventName;
		Spine.AnimationState m_AnimationState;

		bool m_WasFired = false;
		bool m_unsubscribeAfterFiring = false;

		#region Constructors
		void Subscribe (Spine.AnimationState state, Spine.EventData eventDataReference, bool unsubscribe) {
			if (state == null) {
				Debug.LogWarning("AnimationState argument was null. Coroutine will continue immediately.");
				m_WasFired = true;
				return;
			} else if (eventDataReference == null) {
				Debug.LogWarning("eventDataReference argument was null. Coroutine will continue immediately.");
				m_WasFired = true;
				return;
			}

			m_AnimationState = state;
			m_TargetEvent = eventDataReference;
			state.Event += HandleAnimationStateEvent;

			m_unsubscribeAfterFiring = unsubscribe;

		}

		void SubscribeByName (Spine.AnimationState state, string eventName, bool unsubscribe) {
			if (state == null) {
				Debug.LogWarning("AnimationState argument was null. Coroutine will continue immediately.");
				m_WasFired = true;
				return;
			} else if (string.IsNullOrEmpty(eventName)) {
				Debug.LogWarning("eventName argument was null. Coroutine will continue immediately.");
				m_WasFired = true;
				return;
			}
		
			m_AnimationState = state;
			m_EventName = eventName;
			state.Event += HandleAnimationStateEventByName;

			m_unsubscribeAfterFiring = unsubscribe;
		}

		public WaitForSpineEvent (Spine.AnimationState state, Spine.EventData eventDataReference, bool unsubscribeAfterFiring = true) {
			Subscribe(state, eventDataReference, unsubscribeAfterFiring);
		}

		public WaitForSpineEvent (SkeletonAnimation skeletonAnimation, Spine.EventData eventDataReference, bool unsubscribeAfterFiring = true) {			
			// If skeletonAnimation is invalid, its state will be null. Subscribe handles null states just fine.
			Subscribe(skeletonAnimation.state, eventDataReference, unsubscribeAfterFiring);
		}
			
		public WaitForSpineEvent (Spine.AnimationState state, string eventName, bool unsubscribeAfterFiring = true) {
			SubscribeByName(state, eventName, unsubscribeAfterFiring);
		}

		public WaitForSpineEvent (SkeletonAnimation skeletonAnimation, string eventName, bool unsubscribeAfterFiring = true) {
			// If skeletonAnimation is invalid, its state will be null. Subscribe handles null states just fine.
			SubscribeByName(skeletonAnimation.state, eventName, unsubscribeAfterFiring);
		}
		#endregion

		#region Event Handlers
		void HandleAnimationStateEventByName (Spine.TrackEntry trackEntry, Spine.Event e) {
			m_WasFired |= (e.Data.Name == m_EventName);			// Check event name string match.
			if (m_WasFired && m_unsubscribeAfterFiring)
				m_AnimationState.Event -= HandleAnimationStateEventByName;	// Unsubscribe after correct event fires.
		}

		void HandleAnimationStateEvent (Spine.TrackEntry trackEntry, Spine.Event e) {
			m_WasFired |= (e.Data == m_TargetEvent);			// Check event data reference match.
			if (m_WasFired && m_unsubscribeAfterFiring)
				m_AnimationState.Event -= HandleAnimationStateEvent; 		// Usubscribe after correct event fires.
		}
		#endregion

		#region Reuse
		/// <summary>
		/// By default, WaitForSpineEvent will unsubscribe from the event immediately after it fires a correct matching event. 
		/// If you want to reuse this WaitForSpineEvent instance on the same event, you can set this to false.</summary>
		public bool WillUnsubscribeAfterFiring { get { return m_unsubscribeAfterFiring; } set { m_unsubscribeAfterFiring = value; } }

		public WaitForSpineEvent NowWaitFor (Spine.AnimationState state, Spine.EventData eventDataReference, bool unsubscribeAfterFiring = true) {
			((IEnumerator)this).Reset();
			Clear(state);
			Subscribe(state, eventDataReference, unsubscribeAfterFiring);

			return this;
		}

		public WaitForSpineEvent NowWaitFor (Spine.AnimationState state, string eventName, bool unsubscribeAfterFiring = true) {
			((IEnumerator)this).Reset();
			Clear(state);
			SubscribeByName(state, eventName, unsubscribeAfterFiring);

			return this;
		}

		void Clear (Spine.AnimationState state) {
			state.Event -= HandleAnimationStateEvent;
			state.Event -= HandleAnimationStateEventByName;
		}
		#endregion

		#region IEnumerator
		bool IEnumerator.MoveNext () {
			if (m_WasFired) {
				((IEnumerator)this).Reset();	// auto-reset for YieldInstruction reuse
				return false;
			}

			return true;
		}
		void IEnumerator.Reset () { m_WasFired = false; }
		object IEnumerator.Current { get { return null; } }
		#endregion
	}
}