use strafesnet_common::instruction;
use strafesnet_common::mouse::MouseState;
use strafesnet_common::physics::Instruction as PhysicsInputInstruction;
use strafesnet_common::integer::Time;
use strafesnet_common::instruction::TimedInstruction;
use strafesnet_common::timer::{Scaled,Timer,TimerState};
#[derive(Debug)]
pub enum InputInstruction{
	MoveMouse(glam::IVec2),
	MoveRight(bool),
	MoveUp(bool),
	MoveBack(bool),
	MoveLeft(bool),
	MoveDown(bool),
	MoveForward(bool),
	Jump(bool),
	Zoom(bool),
	ResetAndRestart,
	ResetAndSpawn(strafesnet_common::gameplay_modes::ModeId,strafesnet_common::gameplay_modes::StageId),
	PracticeFly,
}
pub enum Instruction{
	Input(InputInstruction),
	Render,
	Resize(winit::dpi::PhysicalSize<u32>),
	ChangeMap(strafesnet_common::map::CompleteMap),
	//SetPaused is not an InputInstruction: the physics doesn't know that it's paused.
	SetPaused(bool),
	//Graphics(crate::graphics_worker::Instruction),
}
pub struct MouseInterpolator{
	//"PlayerController"
	user_settings:crate::settings::UserSettings,
	//"MouseInterpolator"
	timeline:std::collections::VecDeque<TimedInstruction<PhysicsInputInstruction>>,
	last_mouse_time:Time,//this value is pre-transformed to simulation time
	mouse_blocking:bool,
	//"Simulation"
	timer:Timer<Scaled>,
}
impl instruction::InstructionConsumer<Instruction> for MouseInterpolator{
	fn process_instruction(&mut self,ins:TimedInstruction<Instruction>){
		atomic_state_update(&mut self,ins)
	}
}
impl instruction::InstructionEmitter<PhysicsInputInstruction> for MouseInterpolator{
	fn next_instruction(&self,time_limit:Time)->Option<TimedInstruction<PhysicsInputInstruction>>{
		next_instruction_internal(&self,time_limit)
	}
}

impl MouseInterpolator{
	pub fn new(
		physics:crate::physics::PhysicsContext,
		user_settings:crate::settings::UserSettings,
	)->MouseInterpolator{
		MouseInterpolator{
			mouse_blocking:true,
			last_mouse_time:physics.get_next_mouse().time,
			timeline:std::collections::VecDeque::new(),
			timer:Timer::from_state(Scaled::identity(),false),
			physics,
			user_settings,
		}
	}
	fn push_mouse_instruction(&mut self,ins:&TimedInstruction<Instruction>,m:glam::IVec2){
		if self.mouse_blocking{
			//tell the game state which is living in the past about its future
			self.timeline.push_front(TimedInstruction{
				time:self.last_mouse_time,
				instruction:PhysicsInputInstruction::SetNextMouse(MouseState{time:self.timer.time(ins.time),pos:m}),
			});
		}else{
			//mouse has just started moving again after being still for longer than 10ms.
			//replace the entire mouse interpolation state to avoid an intermediate state with identical m0.t m1.t timestamps which will divide by zero
			self.timeline.push_front(TimedInstruction{
				time:self.last_mouse_time,
				instruction:PhysicsInputInstruction::ReplaceMouse(
					MouseState{time:self.last_mouse_time,pos:self.physics.get_next_mouse().pos},
					MouseState{time:self.timer.time(ins.time),pos:m}
				),
			});
			//delay physics execution until we have an interpolation target
			self.mouse_blocking=true;
		}
		self.last_mouse_time=self.timer.time(ins.time);
	}
	fn push(&mut self,time:Time,phys_input:PhysicsInputInstruction){
		//This is always a non-mouse event
		self.timeline.push_back(TimedInstruction{
			time:self.timer.time(time),
			instruction:phys_input,
		});
	}
	/// returns should_empty_queue
	/// may or may not mutate internal state XD!
	fn map_instruction(&mut self,ins:&TimedInstruction<Instruction>)->bool{
		let mut update_mouse_blocking=true;
		match &ins.instruction{
			Instruction::Input(input_instruction)=>match input_instruction{
				&InputInstruction::MoveMouse(m)=>{
					if !self.timer.is_paused(){
						self.push_mouse_instruction(ins,m);
					}
					update_mouse_blocking=false;
				},
				&InputInstruction::MoveForward(s)=>self.push(ins.time,PhysicsInputInstruction::SetMoveForward(s)),
				&InputInstruction::MoveLeft(s)=>self.push(ins.time,PhysicsInputInstruction::SetMoveLeft(s)),
				&InputInstruction::MoveBack(s)=>self.push(ins.time,PhysicsInputInstruction::SetMoveBack(s)),
				&InputInstruction::MoveRight(s)=>self.push(ins.time,PhysicsInputInstruction::SetMoveRight(s)),
				&InputInstruction::MoveUp(s)=>self.push(ins.time,PhysicsInputInstruction::SetMoveUp(s)),
				&InputInstruction::MoveDown(s)=>self.push(ins.time,PhysicsInputInstruction::SetMoveDown(s)),
				&InputInstruction::Jump(s)=>self.push(ins.time,PhysicsInputInstruction::SetJump(s)),
				&InputInstruction::Zoom(s)=>self.push(ins.time,PhysicsInputInstruction::SetZoom(s)),
				&InputInstruction::ResetAndSpawn(mode_id,stage_id)=>{
					self.push(ins.time,PhysicsInputInstruction::Reset);
					self.push(ins.time,PhysicsInputInstruction::SetSensitivity(self.user_settings.calculate_sensitivity()));
					self.push(ins.time,PhysicsInputInstruction::Spawn(mode_id,stage_id));
				},
				InputInstruction::ResetAndRestart=>{
					self.push(ins.time,PhysicsInputInstruction::Reset);
					self.push(ins.time,PhysicsInputInstruction::SetSensitivity(self.user_settings.calculate_sensitivity()));
					self.push(ins.time,PhysicsInputInstruction::Restart);
				},
				InputInstruction::PracticeFly=>self.push(ins.time,PhysicsInputInstruction::PracticeFly),
			},
			//do these really need to idle the physics?
			//sending None dumps the instruction queue
			Instruction::ChangeMap(_)=>self.push(ins.time,PhysicsInputInstruction::Idle),
			Instruction::Resize(_)=>self.push(ins.time,PhysicsInputInstruction::Idle),
			Instruction::Render=>self.push(ins.time,PhysicsInputInstruction::Idle),
			&Instruction::SetPaused(paused)=>{
				if let Err(e)=self.timer.set_paused(ins.time,paused){
					println!("Cannot SetPaused: {e}");
				}
				self.push(ins.time,PhysicsInputInstruction::Idle);
			},
		}
		if update_mouse_blocking{
			//this returns the bool for us
			self.update_mouse_blocking(ins.time)
		}else{
			//do flush that queue
			true
		}
	}
	/// must check if self.mouse_blocking==true before calling!
	fn unblock_mouse(&mut self,time:Time){
		//push an event to extrapolate no movement from
		self.timeline.push_front(TimedInstruction{
			time:self.last_mouse_time,
			instruction:PhysicsInputInstruction::SetNextMouse(MouseState{time:self.timer.time(time),pos:self.physics.get_next_mouse().pos}),
		});
		self.last_mouse_time=self.timer.time(time);
		//stop blocking. the mouse is not moving so the physics does not need to live in the past and wait for interpolation targets.
		self.mouse_blocking=false;
	}
	fn update_mouse_blocking(&mut self,time:Time)->bool{
		if self.mouse_blocking{
			//assume the mouse has stopped moving after 10ms.
			//shitty mice are 125Hz which is 8ms so this should cover that.
			//setting this to 100us still doesn't print even though it's 10x lower than the polling rate,
			//so mouse events are probably not handled separately from drawing and fire right before it :(
			if Time::from_millis(10)<self.timer.time(time)-self.physics.get_next_mouse().time{
				self.unblock_mouse(time);
				true
			}else{
				false
			}
		}else{
			//keep this up to date so that it can be used as a known-timestamp
			//that the mouse was not moving when the mouse starts moving again
			self.last_mouse_time=self.timer.time(time);
			true
		}
	}
	fn empty_queue(&mut self){
		while let Some(instruction)=self.timeline.pop_front(){
			self.physics.run_input_instruction(instruction);
		}
	}
	pub fn handle_instruction(&mut self,ins:&TimedInstruction<Instruction>){
		let should_empty_queue=self.map_instruction(ins);
		if should_empty_queue{
			self.empty_queue();
		}
	}
	pub fn get_frame_state(&self,time:Time)->crate::graphics::FrameState{
		crate::graphics::FrameState{
			body:self.physics.camera_body(),
			camera:self.physics.camera(),
			time:self.timer.time(time),
		}
	}
	pub fn change_map(&mut self,time:Time,map:&strafesnet_common::map::CompleteMap){
		//dump any pending interpolation state
		if self.mouse_blocking{
			self.unblock_mouse(time);
		}
		self.empty_queue();

		//doing it like this to avoid doing PhysicsInstruction::ChangeMap(Rc<CompleteMap>)
		self.physics.generate_models(&map);

		//use the standard input interface so the instructions are written out to bots
		self.handle_instruction(&TimedInstruction{
			time:self.timer.time(time),
			instruction:Instruction::Input(InputInstruction::ResetAndSpawn(
				strafesnet_common::gameplay_modes::ModeId::MAIN,
				strafesnet_common::gameplay_modes::StageId::FIRST,
			)),
		});
	}
	pub const fn user_settings(&self)->&crate::settings::UserSettings{
		&self.user_settings
	}
}