using System;
using System.Linq;
using SLSFramework.General;
using UniRx;
using UnityEngine;
using UnityEngine.Events;

namespace Continentis.MainGame.Commands
{
    public class Cmd_Function : CommandBase
    {
        private readonly float functionDuration;
        private readonly UnityAction function;
        private readonly bool executeAtStart;
        
        public Cmd_Function(float functionDuration, UnityAction function, bool executeAtStart = true) : base(null)
        {
            this.functionDuration = functionDuration;
            this.function = function;
            this.executeAtStart = executeAtStart;
        }
        
        public Cmd_Function(UnityAction function) : base(null)
        {
            this.functionDuration = 0;
            this.function = function;
            this.executeAtStart = true;
        }

        protected override IObservable<Unit> OnExecute(CommandContext outerContext)
        {
            if (functionDuration > 0)
            {
                if (executeAtStart) //在持续时间开始时执行
                {
                    function?.Invoke();
                    return Observable.Timer(TimeSpan.FromSeconds(functionDuration)).AsUnitObservable();
                }

                return Observable.Timer(TimeSpan.FromSeconds(functionDuration))
                    .Do(_ => function?.Invoke())
                    .AsUnitObservable(); //在持续时间结束时执行
            }

            function?.Invoke();
            return Observable.Return(Unit.Default); //如果持续时间为0，立即完成
        }
    }
    
    public class Cmd_ParamFunction<T> : CommandBase where T : class
    {
        private readonly float functionDuration;
        private readonly UnityAction<T> function;
        private readonly bool executeAtStart;
        
        public Cmd_ParamFunction(UnityAction<T> function, CommandContext selfContext = null, bool executeAtStart = true) 
            :base(selfContext)
        {
            this.functionDuration = 0;
            this.function = function;
            this.executeAtStart = executeAtStart;
        }
        
        public Cmd_ParamFunction(float functionDuration, UnityAction<T> function, CommandContext selfContext = null, bool executeAtStart = true) 
            :base(selfContext)
        {
            this.functionDuration = functionDuration;
            this.function = function;
            this.executeAtStart = executeAtStart;
        }

        protected override IObservable<Unit> OnExecute(CommandContext outerContext)
        {
            if (selfContext.context.Count != 1)
            {
                Debug.LogWarning("Cmd_Function 期望 selfContext 只包含一个参数，作为 function 的输入。");
            }
            
            T param = selfContext.context["Target"] as T;
            
            if (param == null)
            {
                Debug.LogWarning("Cmd_Function 未能从 selfContext 中获取到有效的参数。");
            }
            
            if (functionDuration > 0)
            {
                if (executeAtStart) //在持续时间开始时执行
                {
                    function?.Invoke(param);
                    return Observable.Timer(TimeSpan.FromSeconds(functionDuration)).AsUnitObservable();
                }

                return Observable.Timer(TimeSpan.FromSeconds(functionDuration))
                    .Do(_ => function?.Invoke(param))
                    .AsUnitObservable(); //在持续时间结束时执行
            }

            function?.Invoke(param);
            return Observable.Return(Unit.Default); //如果持续时间为0，立即完成
        }
    }
}