use crate::integer::Time;

#[derive(Clone,Debug)]
pub struct TimedInstruction<I,T>{
	pub time:Time<T>,
	pub instruction:I,
}
impl<I,T> TimedInstruction<I,T>{
	#[inline]
	pub fn set_time<TimeInner>(self,new_time:Time<TimeInner>)->TimedInstruction<I,TimeInner>{
		TimedInstruction{
			time:new_time,
			instruction:self.instruction,
		}
	}
}

/// Ensure all emitted instructions are processed before consuming external instructions
pub trait InstructionEmitter<I>{
	type TimeInner;
	fn next_instruction(&self,time_limit:Time<Self::TimeInner>)->Option<TimedInstruction<I,Self::TimeInner>>;
}
/// Apply an atomic state update
pub trait InstructionConsumer<I>{
	type TimeInner;
	fn process_instruction(&mut self,instruction:TimedInstruction<I,Self::TimeInner>);
}
/// If the object produces its own instructions, allow exhaustively feeding them back in
pub trait InstructionFeedback<I,T>:InstructionEmitter<I,TimeInner=T>+InstructionConsumer<I,TimeInner=T>
	where
		Time<T>:Copy,
{
	#[inline]
	fn process_exhaustive(&mut self,time_limit:Time<T>){
		while let Some(instruction)=self.next_instruction(time_limit){
			self.process_instruction(instruction);
		}
	}
}
impl<I,T,X> InstructionFeedback<I,T> for X
	where
		Time<T>:Copy,
		X:InstructionEmitter<I,TimeInner=T>+InstructionConsumer<I,TimeInner=T>,
{}

//PROPER PRIVATE FIELDS!!!
pub struct InstructionCollector<I,T>{
	time:Time<T>,
	instruction:Option<I>,
}
impl<I,T> InstructionCollector<I,T>
	where Time<T>:Copy+PartialOrd,
{
	#[inline]
	pub const fn new(time:Time<T>)->Self{
		Self{
			time,
			instruction:None
		}
	}
	#[inline]
	pub const fn time(&self)->Time<T>{
		self.time
	}
	pub fn collect(&mut self,instruction:Option<TimedInstruction<I,T>>){
		if let Some(ins)=instruction{
			if ins.time<self.time{
				self.time=ins.time;
				self.instruction=Some(ins.instruction);
			}
		}
	}
	pub fn instruction(self)->Option<TimedInstruction<I,T>>{
		//STEAL INSTRUCTION AND DESTROY INSTRUCTIONCOLLECTOR
		self.instruction.map(|instruction|TimedInstruction{
			time:self.time,
			instruction
		})
	}
}